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Sample records for bivalve nacre manifest

  1. Laser Imaging Polarimetry of Nacre.

    Science.gov (United States)

    Jones, Joshua A; Metzler, Rebecca A; D'Addario, Anthony J; Burgess, Carrie; Regan, Brian; Spano, Samantha; Cvarch, Ben A; Galvez, Enrique J

    2018-03-25

    Nacre is a complex biomaterial made of aragonite-tablet bricks and organic mortar that is considerably resilient against breakage. Nacre has been studied with a wide range of laboratory techniques, leading to understanding key fundamentals, and informing the creation of bio-inspired materials. In this article we present an optical polarimetric technique to investigate nacre, taking advantage of the translucence and birefringence of its micro-components. We focus our study on three classes of mollusks that have nacreous shells: bivalve (Pinctada fucata), gastropod (Haliotis asisina and Haliotis rufescens) and cephalopod (Nautilus pompilius). We sent polarized light from a laser through thin samples of nacre and did imaging polarimetry of the transmitted light. We observed clear distinctions between the structures of bivalve and gastropod, due to the spatial variation of their birefringence. The patterns for cephalopod were more similar to bivalve than gastropod. Bleaching of the samples disrupted the transmitted light. Subsequent refilling of the bivalve and gastropod nacre samples with oil produced optical patterns similar to those of unbleached samples. In cephalopod samples we found that bleaching produced irreversible changes in the optical pattern. This article is protected by copyright. All rights reserved.

  2. Polarimetry of Pinctada fucata nacre indicates myostracal layer interrupts nacre structure.

    Science.gov (United States)

    Metzler, Rebecca A; Jones, Joshua A; D'Addario, Anthony J; Galvez, Enrique J

    2017-02-01

    The inner layer of many bivalve and gastropod molluscs consists of iridescent nacre, a material that is structured like a brick wall with bricks consisting of crystalline aragonite and mortar of organic molecules. Myostracal layers formed during shell growth at the point of muscle attachment to the shell can be found interspersed within the nacre structure. Little has been done to examine the effect the myostracal layer has on subsequent nacre structure. Here we present data on the structure of the myostracal and nacre layers from a bivalve mollusc, Pinctada fucata . Scanning electron microscope imaging shows the myostracal layer consists of regular crystalline blocks. The nacre before the layer consists of tablets approximately 400 nm thick, while after the myostracal layer the tablets are approximately 500 nm thick. A new technique, imaging polarimetry, indicates that the aragonite crystals within the nacre following the myostracal layer have greater orientation uniformity than before the myostracal layer. The results presented here suggest a possible interaction between the myostracal layer and subsequent shell growth.

  3. Nanostructured artificial nacre

    Science.gov (United States)

    Tang, Zhiyong; Kotov, Nicholas A.; Magonov, Sergei; Ozturk, Birol

    2003-06-01

    Finding a synthetic pathway to artificial analogs of nacre and bones represents a fundamental milestone in the development of composite materials. The ordered brick-and-mortar arrangement of organic and inorganic layers is believed to be the most essential strength- and toughness-determining structural feature of nacre. It has also been found that the ionic crosslinking of tightly folded macromolecules is equally important. Here, we demonstrate that both structural features can be reproduced by sequential deposition of polyelectrolytes and clays. This simple process results in a nanoscale version of nacre with alternating organic and inorganic layers. The macromolecular folding effect reveals itself in the unique saw-tooth pattern of differential stretching curves attributed to the gradual breakage of ionic crosslinks in polyelectrolyte chains. The tensile strength of the prepared multilayers approached that of nacre, whereas their ultimate Young modulus was similar to that of lamellar bones. Structural and functional resemblance makes clay- polyelectrolyte multilayers a close replica of natural biocomposites. Their nanoscale nature enables elucidation of molecular processes occurring under stress.

  4. Smart Nacre-inspired Nanocomposites.

    Science.gov (United States)

    Peng, Jingsong; Cheng, Qunfeng

    2018-03-15

    Nacre-inspired nanocomposites with excellent mechanical properties have achieved remarkable attention in the past decades. The high performance of nacre-inspired nanocomposites is a good basis for the further application of smart devices. Recently, some smart nanocomposites inspired by nacre have demonstrated good mechanical properties as well as effective and stable stimuli-responsive functions. In this Concept, we summarize the recent development of smart nacre-inspired nanocomposites, including 1D fibers, 2D films and 3D bulk nanocomposites, in response to temperature, moisture, light, strain, and so on. We show that diverse smart nanocomposites could be designed by combining various conventional fabrication methods of nacre-inspired nanocomposites with responsive building blocks and interface interactions. The nacre-inspired strategy is versatile for different kinds of smart nanocomposites in extensive applications, such as strain sensors, displays, artificial muscles, robotics, and so on, and may act as an effective roadmap for designing smart nanocomposites in the future. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Ballistic Impact Behavior of Nacre-Like Laminated Composites Consisting of B4C Tablets and Polyurea Matrix

    Science.gov (United States)

    Grujicic, M.; Snipes, J. S.; Ramaswami, S.

    2016-03-01

    A nacre-like composite armor consisting of B4C tablets and polyurea matrix is modeled, and its ballistic impact behavior and penetration resistance (under a normal and a 15°-oblique impact by a solid right circular cylindrical projectile) were analyzed using a series of transient, nonlinear dynamic, finite-element analyses. Nacre is a biological material constituting the innermost layer of the shells of gastropods and bivalves. It consists of polygonal tablets of aragonite, tessellated to form individual layers and having the adjacent layers as well as the tablets within a layer bonded by a biopolymer. Due to its highly complex hierarchical microstructure, nacre possesses an outstanding combination of mechanical properties, the properties which are far superior to the ones that are predicted using the homogenization techniques such as the rule of mixtures. The results of the transient nonlinear dynamic analysis pertaining to the ballistic impact response and the penetration resistance of the modeled nacre-like armor are compared with their counterparts for the B4C single-block armor having an identical areal density. Furthermore, the effect of various nacre microstructural features (e.g., surface profiling, micron-scale asperities, mineral bridges between the overlapping tablets lying in adjacent layers) on the ballistic penetration resistance of the nacre-like composite armor is investigated in order to identify an optimal nacre-like composite-armor architecture having the largest penetration resistance. The results obtained clearly show that a nacre-like armor possesses a superior penetration resistance relative to its monolithic counterpart, and that the nacre microstructural features considered play a critical role in the armor penetration resistance.

  6. Nacre-like ceramic/polymer laminated composite for use in body-armor applications

    Directory of Open Access Journals (Sweden)

    Mica Grujicic

    2016-01-01

    Full Text Available Nacre is a biological material constituting the innermost layer of the shells of gastropods and bivalves. It consists of polygonal tablets of aragonite, tessellated to form individual layers and having the adjacent layers as well as the tablets within a layer bonded by a biopolymer. Due to its highly complex hierarchical microstructure, nacre possesses an outstanding combination of mechanical properties, the properties which are far superior to the ones that are predicted using the techniques such as the rule of mixture. In the present work, an attempt is made to model a nacre-like composite armor consisting of boron carbide (B4C tablets and polyurea tablet/tablet interfaces. The armor is next investigated with respect to impact by a solid right-circular-cylindrical rigid projectile, using a transient non-linear dynamics finite element analysis. The ballistic-impact response and the penetration resistance of the armor is then compared with that of the B4C monolithic armor having an identical areal density. Furthermore, the effect of various nacre microstructural features (e.g. surface profiling, micron-scale asperities, mineral bridges between the overlapping tablets lying in adjacent layers, and B4C nano-crystallinity on the ballistic-penetration resistance of the composite-armor is investigated in order to identify an optimal nacre-like composite-armor architecture having the largest penetration resistance. The results obtained clearly show that a nacre-like armor possesses a superior penetration resistance relative to its monolithic counterpart, and that the nacre microstructural features considered play a critical role in the armor penetration resistance.

  7. Gradual Ordering in Red Abalone Nacre

    Energy Technology Data Exchange (ETDEWEB)

    Gilbert, P. U. P. A.; Metzler, Rebecca A.; Zhou, Dong; Scholl, Andreas; Doran, Andrew; Young, Anthony; Kunz, Martin; Tamura, Nobumichi; Coppersmith, Susan N.

    2008-09-03

    Red abalone (Haliotis rufescens) nacre is a layered composite biomineral that contains crystalline aragonite tablets confined by organic layers. Nacre is intensely studied because its biologically controlled microarchitecture gives rise to remarkable strength and toughness, but the mechanisms leading to its formation are not well understood. Here we present synchrotron spectromicroscopy experiments revealing that stacks of aragonite tablet crystals in nacre are misoriented with respect to each other. Quantitative measurements of crystal orientation, tablet size, and tablet stacking direction show that orientational ordering occurs not abruptly but gradually over a distance of 50 {micro}m. Several lines of evidence indicate that different crystal orientations imply different tablet growth rates during nacre formation. A theoretical model based on kinetic and gradual selection of the fastest growth rates produces results in qualitative and quantitative agreement with the experimental data and therefore demonstrates that ordering in nacre is a result of crystal growth kinetics and competition either in addition or to the exclusion of templation by acidic proteins as previously assumed. As in other natural evolving kinetic systems, selection of the fastest-growing stacks of tablets occurs gradually in space and time. These results suggest that the self-ordering of the mineral phase, which may occur completely independently of biological or organic-molecule control, is fundamental in nacre formation.

  8. Discrete element modeling of microstructure of nacre

    Science.gov (United States)

    Chandler, Mei Qiang; Cheng, Jing-Ru C.

    2018-04-01

    The microstructure of nacre consists of polygon-shaped aragonite mineral tablets bonded by very thin layers of organic materials and is organized in a brick-mortar morphology. In this research, the discrete element method was utilized to model this structure. The aragonite mineral tablets were modeled with three-dimensional polygon particles generated by the Voronoi tessellation method to represent the Voronoi-like patterns of mineral tablets assembly observed in experiments. The organic matrix was modeled with a group of spring elements. The constitutive relations of the spring elements were inspired from the experimental results of organic molecules from the literature. The mineral bridges were modeled with simple elastic bonds with the parameters based on experimental data from the literature. The bulk stress-strain responses from the models agreed well with experimental results. The model results show that the mineral bridges play important roles in providing the stiffness and yield strength for the nacre, while the organic matrix in providing the ductility for the nacre. This work demonstrated the suitability of particle methods for modeling microstructures of nacre.

  9. Voyaging around nacre with the X-ray shuttle: From bio-mineralisation to prosthetics via mollusc phylogeny

    International Nuclear Information System (INIS)

    Chateigner, D.; Ouhenia, S.; Krauss, C.; Hedegaard, C.; Gil, O.; Morales, M.; Lutterotti, L.; Rousseau, M.; Lopez, E.

    2010-01-01

    Research highlights: → Nacre could be a non ancestral form of calcium carbonate in molluscs. → Texture terms as useful links to ancestors in classification. → X-ray diffraction useful for biomineralisation, phylogeny, cladistic and implantology. → Farming conditions do not influence much shell growth. → Electrodeposition of aragonite as future technique for implant coating. - Abstract: Strong textures of mollusc shell layers are utilised to provide phylogenetic information. Aragonitic and calcitic layers are the targets here, inside which nacre layers, but not only, play a specific role. At the light of the texture patterns and a parcimonious approach, nacre appears not as an ancestral form of calcium carbonate in mollusc layers. Also, from texture terms we can propose some links to ancestral fossilised species. The aragonite unit-cell distortions due to macromolecule complex insertions in the microstructures are measured on raw specimens for several aragonite layers of gastropods and bivalves. The textural information is used to provide precise structural determination of the biogenic aragonite. Such information might provide useful lights on the biomineralisation processes in the future, in cladistic approaches. Farming conditions are shown not to influence much shell textures of Helix aspersa aspersa. Closely related species exhibit globally close textures, among which three are good candidates for bone neogeneration and which textures are identical. Electrodeposition of aragonite, with inclusion of molecular extract from shell species, results in nacre-like layers exhibiting structural distortions similar to known inductive layers. X-ray diffraction experiments are shown to provide invaluable insights in testing biomineralisation and phylogenetic hypotheses.

  10. Voyaging around nacre with the X-ray shuttle: From bio-mineralisation to prosthetics via mollusc phylogeny

    Energy Technology Data Exchange (ETDEWEB)

    Chateigner, D., E-mail: daniel.chateigner@ensicaen.fr [CRISMAT-ENSICAEN, IUT-Caen, Universite de Caen Basse-Normandie, 6 Bd. M. Juin, 14050 Caen (France); Ouhenia, S. [CRISMAT-ENSICAEN, IUT-Caen, Universite de Caen Basse-Normandie, 6 Bd. M. Juin, 14050 Caen (France); Lab. De Physique, Faculte des Sciences Exactes, Bejaia 06000 (Algeria); Krauss, C.; Hedegaard, C. [CRISMAT-ENSICAEN, IUT-Caen, Universite de Caen Basse-Normandie, 6 Bd. M. Juin, 14050 Caen (France); Gil, O. [ERPCB, IUT-Caen, Universite de Caen Basse-Normandie, 6 Bd. M. Juin, 14050 Caen (France); Morales, M. [CIMAP-ENSICAEN, Universite de Caen Basse-Normandie, 6 Bd. M. Juin, 14050 Caen (France); Lutterotti, L. [Department of Materials Engineering, Engineering Faculty, University of Trento, via Mesiano, 77 - 38123 Trento (Italy); Rousseau, M. [UMR 7561 CNRS, Nancy University, BP184, 54505 Vandoeuvre les Nancy,France (France); Lopez, E. [UMR7208 BOREA, CNRS/Museum National d' Histoire Naturelle, 43, rue Cuvier 75231, Paris Cedex 05 (France)

    2010-11-25

    Research highlights: {yields} Nacre could be a non ancestral form of calcium carbonate in molluscs. {yields} Texture terms as useful links to ancestors in classification. {yields} X-ray diffraction useful for biomineralisation, phylogeny, cladistic and implantology. {yields} Farming conditions do not influence much shell growth. {yields} Electrodeposition of aragonite as future technique for implant coating. - Abstract: Strong textures of mollusc shell layers are utilised to provide phylogenetic information. Aragonitic and calcitic layers are the targets here, inside which nacre layers, but not only, play a specific role. At the light of the texture patterns and a parcimonious approach, nacre appears not as an ancestral form of calcium carbonate in mollusc layers. Also, from texture terms we can propose some links to ancestral fossilised species. The aragonite unit-cell distortions due to macromolecule complex insertions in the microstructures are measured on raw specimens for several aragonite layers of gastropods and bivalves. The textural information is used to provide precise structural determination of the biogenic aragonite. Such information might provide useful lights on the biomineralisation processes in the future, in cladistic approaches. Farming conditions are shown not to influence much shell textures of Helix aspersa aspersa. Closely related species exhibit globally close textures, among which three are good candidates for bone neogeneration and which textures are identical. Electrodeposition of aragonite, with inclusion of molecular extract from shell species, results in nacre-like layers exhibiting structural distortions similar to known inductive layers. X-ray diffraction experiments are shown to provide invaluable insights in testing biomineralisation and phylogenetic hypotheses.

  11. Design strategies and applications of nacre-based biomaterials.

    Science.gov (United States)

    Gerhard, Ethan Michael; Wang, Wei; Li, Caiyan; Guo, Jinshan; Ozbolat, Ibrahim Tarik; Rahn, Kevin Michael; Armstrong, April Dawn; Xia, Jingfen; Qian, Guoying; Yang, Jian

    2017-05-01

    The field of tissue engineering and regenerative medicine relies heavily on materials capable of implantation without significant foreign body reactions and with the ability to promote tissue differentiation and regeneration. The field of bone tissue engineering in particular requires materials capable of providing enhanced mechanical properties and promoting osteogenic cell lineage commitment. While bone repair has long relied almost exclusively on inorganic, calcium phosphate ceramics such as hydroxyapatite and their composites or on non-degradable metals, the organically derived shell and pearl nacre generated by mollusks has emerged as a promising alternative. Nacre is a naturally occurring composite material composed of inorganic, calcium carbonate plates connected by a framework of organic molecules. Similar to mammalian bone, the highly organized microstructure of nacre endows the composite with superior mechanical properties while the organic phase contributes to significant bioactivity. Studies, both in vitro and in vivo, have demonstrated nacre's biocompatibility, biodegradability, and osteogenic potential, which are superior to pure inorganic minerals such as hydroxyapatite or non-degradable metals. Nacre can be used directly as a bulk implant or as part of a composite material when combined with polymers or other ceramics. While nacre has demonstrated its effectiveness in multiple cell culture and animal models, it remains a relatively underexplored biomaterial. This review introduces the formation, structure, and characteristics of nacre, and discusses the present and future uses of this biologically-derived material as a novel biomaterial for orthopedic and other tissue engineering applications. Mussel derived nacre, a biological composite composed of mineralized calcium carbonate platelets and interplatelet protein components, has recently gained interest as a potential alternative ceramic material in orthopedic biomaterials, combining the

  12. Osteogenic Potency of Nacre on Human Mesenchymal Stem Cells

    Science.gov (United States)

    Green, David W.; Kwon, Hyuk-Jae; Jung, Han-Sung

    2015-01-01

    Nacre seashell is a natural osteoinductive biomaterial with strong effects on osteoprogenitors, osteoblasts, and osteoclasts during bone tissue formation and morphogenesis. Although nacre has shown, in one study, to induce bridging of new bone across large non-union bone defects in 8 individual human patients, there have been no succeeding human surgical studies to confirm this outstanding potency. But the molecular mechanisms associated with nacre osteoinduction and the influence on bone marrow-derived mesenchymal stem cells (BMSC’s), skeletal stem cells or bone marrow stromal cells remain elusive. In this study we highlight the phenotypic and biochemical effects of Pinctada maxima nacre chips and the global nacre soluble protein matrix (SPM) on primary human bone marrow-derived stromal cells (hBMSCs) in vitro. In static co-culture with nacre chips, the hBMSCs secreted Alkaline phosphatase (ALP) at levels that exceeded bone morphogenetic protein (rhBMP-2) treatment. Concentrated preparation of SPM applied to Stro-1 selected hBMSC’s led to rapid ALP secretions, at concentrations exceeding the untreated controls even in osteogenic conditions. Within 21 days the same population of Stro-1 selected hBMSCs proliferated and secreted collagens I–IV, indicating the premature onset of an osteoblast phenotype. The same SPM was found to promote unselected hBMSC differentiation with osteocalcin detected at 7 days, and proliferation increased at 7 days in a dose-dependent manner. In conclusion, nacre particles and nacre SPM induced the early stages of human bone cell differentiation, indicating that they may be promising soluble factors with osteoinductive capacity in primary human bone cell progenitors such as, hBMSC’s. PMID:25666352

  13. Deformation and Fracture Mechanisms of Bone and Nacre

    Science.gov (United States)

    Wang, Rizhi; Gupta, Himadri S.

    2011-08-01

    Bone and nacre are the most-known biological hard tissues to materials researchers. Although highly mineralized, both bone and nacre are amazingly tough and exhibit remarkable inelasticity, properties that are still beyond the reach of many modern ceramic materials. Very interestingly, the two hard tissues seem to have adopted totally different structural strategies for achieving mechanical robustness. Starting from a true nanocomposite of the mineralized collagen fibril and following up to seven levels of hierarchical organization, bone is built on a structure with extreme complexity. In contrast, nacre possesses a structure of surprising simplicity. Polygonal mineral tablets of micrometer size are carefully cemented together into a macroscopic wonder. A comparative analysis of the structure-property relations in bone and nacre helps us to unveil the underlying mechanisms of this puzzling phenomenon. In this review, we critically compare the various levels of structures and their mechanical contributions between bone and nacre, with a focus on inelasticity and the toughening process. We demonstrate that, although nacre and bone differ from each other in many aspects, they have adopted very similar deformation and toughening mechanisms.

  14. Viruses infecting bivalve molluscs

    OpenAIRE

    Renault, Tristan; Novoa, Beatriz

    2004-01-01

    Bivalve molluscs are filter feeders and as a consequence they may bioaccumulate in their tissues viruses that infect humans and higher vertebrates. However, there have also been described mortalities of bivalve molluscs associated with viruses belonging to different families. Mass mortalities of adult Portuguese oysters, Crassostrea angulata, among French livestocks (between 1967 and 1973) were associated with irido-like virus infections. Herpesviruses were reported in the eastern oyster, Pac...

  15. Nacre extract restores the mineralization capacity of subchondral osteoarthritis osteoblasts.

    Science.gov (United States)

    Brion, A; Zhang, G; Dossot, M; Moby, V; Dumas, D; Hupont, S; Piet, M H; Bianchi, A; Mainard, D; Galois, L; Gillet, P; Rousseau, M

    2015-12-01

    Osteoarthritis (OA) is the most common cause of joint chronic pain and involves the entire joints. Subchondral osteoarthritic osteoblasts present a mineralization defect and, to date, only a few molecules (Vitamin D3 and Bone Morphogenetic Protein2) could improve the mineralization potential of this cell type. In this context, we have tested for the first time the effect of nacre extract on the mineralization capacity of osteoblasts from OA patients. Nacre extract is known to contain osteogenic molecules which have demonstrated their activities notably on the MC3T3 pre-osteoblastic cell line. For this goal, molecules were extracted from nacre (ESM, Ethanol Soluble Matrix) and tested on osteoblasts of the subchondral bone from OA patients undergoing total knee replacement and on MC3T3 cells for comparison. We chose to investigate the mineralization with Alizarin Red staining and with the study of extracellular matrix (ECM) structure and composition. In a complementary way the structure of the ECM secreted during the mineralization phase was investigated using second harmonic generation (SHG). Nacre extract was able to induce the early presence (after 7 days) of precipitated calcium in cells. Raman spectroscopy and electron microscopy showed the presence of nanograins of an early crystalline form of calcium phosphate in OA osteoblasts ECM and hydroxyapatite in MC3T3 ECM. SHG collagen fibers signal was present in both cell types but lower for OA osteoblasts. In conclusion, nacre extract was able to rapidly restore the mineralization capacity of osteoarthritis osteoblasts, therefore confirming the potential of nacre as a source of osteogenic compounds. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Caracterisation des hemocytes d''un mollusque bivalve marin, la nacre, Pinna nobilis L. 1758

    OpenAIRE

    Henry, M; Vicente, N; Houache, N

    1991-01-01

    The study of tinctorial affinities, in vitro behaviour and ultrastructure of the hemocytes of Pinna nobilis allows us to group them into two main families: basophilic, neutrophilic and acidophilic granulocytes; hyalinocytes, three categories can be distinguished among these cells: small hyalinocytes, hyalinocytes containing smooth endoplasmic reticulum and the macrophage population. The hemocytes participate in the regulation of metabolism by the storage and degradation of glycogen. They cont...

  17. Computer vision based nacre thickness measurement of Tahitian pearls

    Science.gov (United States)

    Loesdau, Martin; Chabrier, Sébastien; Gabillon, Alban

    2017-03-01

    The Tahitian Pearl is the most valuable export product of French Polynesia contributing with over 61 million Euros to more than 50% of the total export income. To maintain its excellent reputation on the international market, an obligatory quality control for every pearl deemed for exportation has been established by the local government. One of the controlled quality parameters is the pearls nacre thickness. The evaluation is currently done manually by experts that are visually analyzing X-ray images of the pearls. In this article, a computer vision based approach to automate this procedure is presented. Even though computer vision based approaches for pearl nacre thickness measurement exist in the literature, the very specific features of the Tahitian pearl, namely the large shape variety and the occurrence of cavities, have so far not been considered. The presented work closes the. Our method consists of segmenting the pearl from X-ray images with a model-based approach, segmenting the pearls nucleus with an own developed heuristic circle detection and segmenting possible cavities with region growing. Out of the obtained boundaries, the 2-dimensional nacre thickness profile can be calculated. A certainty measurement to consider imaging and segmentation imprecisions is included in the procedure. The proposed algorithms are tested on 298 manually evaluated Tahitian pearls, showing that it is generally possible to automatically evaluate the nacre thickness of Tahitian pearls with computer vision. Furthermore the results show that the automatic measurement is more precise and faster than the manual one.

  18. Alteration of shell nacre micromorphology in blue mussel Mytilus edulis after exposure to free-ionic silver and silver nanoparticles.

    Science.gov (United States)

    Zuykov, Michael; Pelletier, Emilien; Belzile, Claude; Demers, Serge

    2011-07-01

    This study describes the morphology of inner shell surface (ISS) of the blue mussel Mytilus edulis Linnaeus after short-term exposures to radiolabeled silver in free-ionic ((110m)Ag(+)) and engineered nanoparticulate ((110m)AgNPs, silver in starting solutions was used in a similar low concentration (∼15 Bq mL(-1)) for both treatments. After exposure experiments radiolabeled silver was leached from the ISS using HCl. It concentration for shells from both treatments was ∼0.5 Bq mL(-1). Whole ISS of young individuals and prismatic layer of adults showed no evidence of any major alteration process after silver uptake. However, the nacre portion of adult mussels exposed to both treatments revealed distinct doughnut shape structures (DSS) formed by calcium carbonate micrograins that covered the surface of aragonite tablets. Scanning electron microscope (SEM) imaging revealed the existence of only minor differences in DSS morphology between mussels exposed to Ag(+) and AgNPs. From literature survey, DSS were also found in bivalves exposed to Cd(2+). The DSS occurring in a specimen of a field-collected bivalve is also shown. Formation of distinctive DSS can be explained by a disturbance of the shell calcification mechanism. Although the occurrence of DSS is not exclusively associated with metal bioavailability to the mussels, the morphology of DSS seems to be linked to the speciation of the metal used in the uptake experiments. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Characteristics and Causes for Non-Accrued Clinical Research (NACR) at an Academic Medical Institution.

    Science.gov (United States)

    Tice, Debra G; Carroll, Kelly A; Bhatt, Karishma H; Belknap, Steven M; Mai, David; Gipson, Heather J; West, Dennis P

    2013-06-01

    The impact of non-accrued clinical research (NACR) represents an important economic burden that is under consideration as the U.S. Department of Health and Human Services looks into reforming the regulations governing IRB review. NACR refers to clinical research projects that fail to enroll subjects. A delineation of the issues surrounding NACR is expected to enhance subject accrual and to minimize occurrence of NACR. The authors assessed demographics, characteristics, and reasons for NACR at an academic medical center, including time trends, funding source, research team (principal investigator, department), IRB resource utilization (IRB level of review, number of required IRB reviews, initial IRB turn-around time, and duration of NACR). The authors analyzed data from 848 clinical research study closures during 2010 and 2011 to determine proportion, incidence, and characteristics of NACR. Studies with subject enrollment during the same time period were used as a comparative measure. Data from 704 (83.0%) study closures reported enrollment of 1 or more subjects while 144 (17.0 %) reported NACR (zero enrollment). PI-reported reasons for NACR included: 32 (22.2%) contract or funding issues; 43 (30.0%) insufficient study-dedicated resources; 41 (28.4%) recruitment issues; 17 (11.8%) sponsor-initiated study closure and 11 (7.6%) were "other/reason unreported". NACR is not uncommon, affecting about one in six clinical research projects in the study population and reported to be more common in some other institutions. The complex and fluid nature of research conduct, non-realistic enrollment goals, and delays in both the approval and/or accrual processes contribute to NACR. Results suggest some simple strategies that investigators and institutions may use to reduce NACR, including careful feasibility assessment, reduction of institutional delays, and prompt initiation of subject accrual for multi-center studies using competitive enrollment. Institutional action to

  20. Printing nature: Unraveling the role of nacre's mineral bridges.

    Science.gov (United States)

    Gu, Grace X; Libonati, Flavia; Wettermark, Susan D; Buehler, Markus J

    2017-12-01

    Creating materials with strength and toughness has been a long-sought goal. Conventional engineering materials often face a trade-off between strength and toughness, prompting researchers seeking to overcome these limitations to explore more sophisticated materials, such as composites. This paradigm shift in material design is spurred by nature, which exhibits a plethora of heterogeneous materials that offer outstanding material properties, and many natural materials are widely regarded as examples of high-performing hybrid materials. A classic example is nacre, also known as mother-of-pearl, which boasts a combination of high stiffness, strength, and fracture toughness. Various microstructural features contribute to the toughness of nacre, including mineral bridges (MBs), nano-asperities, and waviness of the constituent platelets. Recent research in biomimicry suggests that MBs contribute to the high strength and toughness observed in nacre and nacre-inspired materials. However, previous work in this area did not allow for complete control over the length scale of the bridges and had limitations on the volume fraction of mineral content. In this work, we present a systematic investigation elucidating the effects of structural parameters, such as volume fraction of mineral phase and density of MBs, on the mechanical response of nacre-inspired additive manufactured composites. Our results demonstrate that it is possible to tune the composite properties by tuning sizes and content of structural features (e.g. MBs and mineral content) in a heterogeneous material. Looking forward, this systematic approach enables materials-by-design of complex architectures to tackle demanding engineering challenges in the future. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Imaging Inelastic Fracture Processes in Biomimetic Nanocomposites and Nacre by Laser Speckle for Better Toughness.

    Science.gov (United States)

    Verho, Tuukka; Karppinen, Pasi; Gröschel, André H; Ikkala, Olli

    2018-01-01

    Mollusk nacre is a prototypical biological inorganic-organic composite that combines high toughness, stiffness, and strength by its brick-and-mortar microstructure, which has inspired several synthetic mimics. Its remarkable fracture toughness relies on inelastic deformations at the process zone at the crack tip that dissolve stress concentrations and stop cracks. The micrometer-scale structure allows resolving the size and shape of the process zone to understand the fracture processes. However, for better scalability, nacre-mimetic nanocomposites with aligned inorganic or graphene nanosheets are extensively pursued, to avoid the packing problems of mesoscale sheets like in nacre or slow in situ biomineralization. This calls for novel methods to explore the process zone of biomimetic nanocomposites. Here the fracture of nacre and nacre-inspired clay/polymer nanocomposite is explored using laser speckle imaging that reveals the process zone even in absence of changes in optical scattering. To demonstrate the diagnostic value, compared to nacre, the nacre-inspired nanocomposite develops a process zone more abruptly with macroscopic crack deflection shown by a flattened process zone. In situ scanning electron microscopy suggests similar toughening mechanisms in nanocomposite and nacre. These new insights guide the design of nacre-inspired nanocomposites toward better mechanical properties to reach the level of synergy of their biological model.

  2. Viruses of bivalve shellfish

    OpenAIRE

    Renault, Tristan

    2006-01-01

    Les mollusques bivalves sont des filtreurs et de ce fait ils peuvent accumuler dans leurs tissus des virus d'origine anthropique. Par ailleurs, des mortalités ont été rapportées chez les bivalves en association à la détection de virus apparentés à différentes familles. Ainsi, des mortalités massives de l'huître portugaise, Crassostrea angulata, ont été observées entre 1967 et 1973 en France et associées à la présence de virus interprétés comme appartenant à la famille des Iridoviridae. Par ai...

  3. Nacre calcification in the freshwater mussel Unio pictorum: carbonic anhydrase activity and purification of a 95 kDa calcium-binding glycoprotein.

    Science.gov (United States)

    Marie, Benjamin; Luquet, Gilles; Bédouet, Laurent; Milet, Christian; Guichard, Nathalie; Medakovic, Davorin; Marin, Frédéric

    2008-10-13

    The formation of the molluscan shell is finely tuned by macromolecules of the shell organic matrix. Previous results have shown that the acid-soluble fraction of the nacre matrix of the freshwater paleoheterodont bivalve Unio pictorum shell displays a number of remarkable properties, such as calcium-binding activity, the presence of extensive glycosylations and the capacity to interfere at low concentration with in vitro calcium carbonate precipitation. Here we have found that the nacre-soluble matrix exhibits a carbonic anhydrase activity, an important function in calcification processes. This matrix is composed of three main proteinaceous discrete fractions. The one with the highest apparent molecular weight is a 95 kDa glycoprotein that is specific to the nacreous layer. P95, as it is provisionally named, is enriched in Gly, Glx and Asx and exhibits an apparent pI value of approximately 4, or approximately 7 when chemically deglycosylated. Furthermore, its glycosyl moiety, consisting of sulfated polysaccharides, is involved in calcium binding. Purified fractions of the three main proteins were digested with trypsin, and the resulting peptides were analysed by mass spectrometry. Our results suggest that identical peptides are constitutive domains of the different proteins. Partial primary structures were obtained by de novo sequencing and compared with known sequences from other mollusc shell proteins. Our results are discussed from an evolutionary viewpoint.

  4. Can bivalve veligers escape feeding currents of adult bivalves?

    NARCIS (Netherlands)

    Troost, K.; Veldhuizen, R.; Stamhuis, E.J.; Wolff, W.J.

    2008-01-01

    While the stock of introduced Pacific oysters (Crassostrea gigas) increased in the Oosterschelde estuary (SW Netherlands), so did the filtration pressure of all bivalve species together. In the same period, stocks of native bivalves declined slightly. The expansion of Pacific oysters in Dutch

  5. Recirculation nursery systems for bivalves

    NARCIS (Netherlands)

    Kamermans, P.; Blanco Garcia, A.; Joaquim, Sandra; Matias, Domitilia; Magnesen, Thorolf; Nicolas, J.; Petten, Bruno; Robert, Rene

    2016-01-01

    n order to increase production of bivalves in hatcheries and nurseries, the development of new technology and its integration into commercial bivalve hatcheries is important. Recirculation aquaculture systems (RASs) have several advantages: high densities of the species can be cultured resulting in

  6. Metabolites of saxitoxin analogues in bivalves contaminated by Gymnodinium catenatum.

    Science.gov (United States)

    Vale, Paulo

    2010-01-01

    Bivalve metabolites of saxitoxin analogues, not present in microalgae, were recently described as an important toxin fraction in mussels contaminated by Alexandrium tamarense. These possess very low fluorescence, and require mass spectrometry detection. HILIC-MS was implemented to look for these metabolites in bivalves contaminated during Gymnodinium catenatum blooms at the Portuguese coast. The presence of M1 was tentatively identified in several bivalves, ranging from estuarine (Mytilus galloprovinciallis, Cerastoderma edule and Ruditapes decussatus) to oceanic habitat (Donax trunculus and Ensis spp.). It was hypothesized that M1 could contribute to an important fraction of the profile of STX analogues. M1 was more abundant in estuarine bivalves that retain longer PSP toxins, in the following order: mussels>cockles>clams. These data highlight that the study by fluorimetry alone of the carbamoyl, N-sulfocarbamoyl, and decarbamoyl families is manifestly insufficient to fully understand toxin dynamics in bivalves feeding on G. catenatum without a proper study of hydroxybenzoate and hydroxylated M-toxins.

  7. Effects of nacre-coated titanium surfaces on cell proliferation and ...

    African Journals Online (AJOL)

    DR. NJ TONUKARI

    2011-11-02

    Lacefield, 1988). Nevertheless, ... and shell of a seawater abalone (Fritz et al., 1994). In light of these findings, we previously ..... Effect of water-soluble matrix fraction extracted from the nacre of Pinctada maxima on the alkaline ...

  8. Superstretchable Nacre-Mimetic Graphene/Poly(vinyl alcohol) Composite Film Based on Interfacial Architectural Engineering.

    Science.gov (United States)

    Zhao, Nifang; Yang, Miao; Zhao, Qian; Gao, Weiwei; Xie, Tao; Bai, Hao

    2017-05-23

    Through designing hierarchical structures, particularly optimizing the chemical and architectural interactions at its inorganic/organic interface, nacre has achieved an excellent combination of contradictory mechanical properties such as strength and toughness, which is highly demanded yet difficult to achieve by most synthetic materials. Most techniques applied to develop nacre-mimetic composites have been focused on mimicking the "brick-and-mortar" structure, but the interfacial architectural features, especially the asperities and mineral bridges of "bricks", have been rarely concerned, which are of equal importance for enhancing mechanical properties of nacre. Here, we used a modified bidirectional freezing method followed by uniaxial pressing and chemical reduction to assemble a nacre-mimetic graphene/poly(vinyl alcohol) composite film, with both asperities and bridges introduced in addition to the lamellar layers to mimic the interfacial architectural interactions found in nacre. As such, we have developed a composite film that is not only strong (up to ∼150.9 MPa), but also tough (up to ∼8.50 MJ/m 3 ), and highly stretchable (up to ∼10.44%), difficult to obtain by other methods. This was all achieved by only interfacial architectural engineering within the traditional "brick-and-mortar" structure, without introducing a third component or employing chemical cross-linker as in some other nacre-mimetic systems. More importantly, we believe that the design principles and processing strategies reported here can also be applied to other material systems to develop strong and stretchable materials.

  9. Bivalve carrying capacity in coastal ecosystems

    NARCIS (Netherlands)

    Dame, R.F.; Prins, T.C.

    1998-01-01

    carrying capacity of suspension feeding bivalves in 11 coastal and estuarine ecosystems is examined. Bivalve carrying capacity is defined in terms of water mass residence time, primary production time and bivalve clearance time. Turnover times for the 11 ecosystems are compared both two and three

  10. Galeommatid bivalves from Phuket, Thailand

    DEFF Research Database (Denmark)

    Lützen, Jørgen; Nielsen, Claus

    2005-01-01

    Twenty-seven species of galeommatid bivalves from six genera have been collected at intertidal reef flats near Phuket Marine Biological Center, Thailand (Andaman Sea, Indian Ocean). Fourteen of the species are new to science and a new genus (Nudiscintilla gen. nov.) has been established. The spec......Twenty-seven species of galeommatid bivalves from six genera have been collected at intertidal reef flats near Phuket Marine Biological Center, Thailand (Andaman Sea, Indian Ocean). Fourteen of the species are new to science and a new genus (Nudiscintilla gen. nov.) has been established...

  11. Layered nanocomposites inspired by the structure and mechanical properties of nacre.

    Science.gov (United States)

    Wang, Jianfeng; Cheng, Qunfeng; Tang, Zhiyong

    2012-02-07

    Nacre (mother-of-pearl), made of inorganic and organic constituents (95 vol% aragonite calcium carbonate (CaCO(3)) platelets and 5 vol% elastic biopolymers), possesses a unique combination of remarkable strength and toughness, which is compatible for conventional high performance materials. The excellent mechanical properties are related to its hierarchical structure and precisely designed organic-inorganic interface. The rational design of aragonite platelet strength, aspect ratio of aragonite platelets, and interface strength ensures that the strength of nacre is maximized under platelet pull-out failure mode. At the same time, the synergy of strain hardening mechanisms acting over multiple scales results in platelets sliding on one another, and thus maximizes the energy dissipation of viscoplastic biopolymers. The excellent integrated mechanical properties with hierarchical structure have inspired chemists and materials scientists to develop biomimetic strategies for artificial nacre materials. This critical review presents a broad overview of the state-of-the-art work on the preparation of layered organic-inorganic nanocomposites inspired by nacre, in particular, the advantages and disadvantages of various biomimetic strategies. Discussion is focused on the effect of the layered structure, interface, and component loading on strength and toughness of nacre-mimic layered nanocomposites (148 references). This journal is © The Royal Society of Chemistry 2012

  12. Contact problem for a composite material with nacre inspired microstructure

    Science.gov (United States)

    Berinskii, Igor; Ryvkin, Michael; Aboudi, Jacob

    2017-12-01

    Bi-material composites with nacre inspired brick and mortar microstructures, characterized by stiff elements of one phase with high aspect ratio separated by thin layers of the second one, are considered. Such microstructure is proved to provide an efficient solution for the problem of a crack arrest. However, contrary to the case of a homogeneous material, an external pressure, applied to a part of the composite boundary, can cause significant tensile stresses which increase the danger of crack nucleation. Investigation of the influence of microstructure parameters on the magnitude of tensile stresses is performed by means of the classical Flamant-like problem of an orthotropic half-plane subjected to a normal external distributed loading. Adequate analysis of this problem represents a serious computational task due to the geometry of the considered layout and the high contrast between the composite constituents. This difficulty is presently circumvented by deriving a micro-to-macro analysis in the framework of which an analytical solution of the auxiliary elasticity problem, followed by the discrete Fourier transform and the higher-order theory are employed. As a result, full scale continuum modeling of both composite constituents without employing any simplifying assumptions is presented. In the framework of the present proposed modeling, the influence of stiff elements aspect ratio on the overall stress distribution is demonstrated.

  13. Anodontites trapesialis (LAMARCK, 1819: a bivalve parasite of freshwater fishes / Anodontites trapesialis (LAMARCK, 1819: um bivalve parasito de peixes de água doce

    Directory of Open Access Journals (Sweden)

    Ângela Teresa Silva-Souza

    2008-08-01

    Full Text Available The bivalve mollusk Anodontites trapesialis has been indicated as an alternative source for aquaculture because it is considered a food of good nutritional value with a protein content close to that of fish. Its shells can be utilized as fertilizer and mixed to the food of domestic animals, and the nacre can be used to manufacture buttons and crafts. However, the larvae of A. trapesialis, which are the lasidium type, are obligatory parasites of freshwater fishes, and the introduction of this bivalve in fish farm tanks have caused trouble and losses for producers. Nothing is known, however, about their development in these environments. On the other hand, it should be pointed out that A. trapesialis is on Brazil’s list of species threatened with extinction. This article provides a compilation of information present in the literature, offering a detailed review, with the aim of presenting a general panorama of what is known about Anodontites trapesialis and its larval parasitism of fishes.O molusco bivalve, Anodontites trapesialis, tem sido indicado como fonte alternativa para a aqüicultura, por ser considerado um alimento de bom valor nutricional com um conteúdo protéico próximo ao do pescado. Suas conchas podem ser utilizadas como fertilizantes calcáreos e ser agregadas a alimentos de animais domésticos e o nácar pode ser utilizado para fabricar botões e artesanatos. No entanto, as larvas de A. trapesialis, que são do tipo lasidium, são parasitas obrigatórias de peixes de água doce e a introdução desse bivalve em tanques de piscicultura tem causado transtornos e prejuízos aos produtores. Nada se conhece, porém, sobre o seu desenvolvimento nesses ambientes. Por outro lado, ressalta-se que A. trapesialis consta da lista brasileira de espécies ameaçadas de extinção. No presente artigo são compiladas as informações presentes na literatura, em uma revisão detalhada, com o objetivo de apresentar o panorama geral do

  14. Plastic deformation in nano-scale multilayer materials — A biomimetic approach based on nacre

    Energy Technology Data Exchange (ETDEWEB)

    Lackner, Juergen M., E-mail: juergen.lackner@joanneum.at [JOANNEUM RESEARCH Forschungsges.m.b.H., Institute for Surface Technologies and Photonics, Functional Surfaces, Leobner Strasse 94, A-8712 Niklasdorf (Austria); Waldhauser, Wolfgang [JOANNEUM RESEARCH Forschungsges.m.b.H., Institute for Surface Technologies and Photonics, Functional Surfaces, Leobner Strasse 94, A-8712 Niklasdorf (Austria); Major, Boguslaw; Major, Lukasz [Polish Academy of Sciences, Institute of Metallurgy and Materials Sciences, IMIM-PAN, ul. Reymonta 25, PL-30059 Krakow (Poland); Kot, Marcin [University of Science and Technology, AGH, Aleja Adama Mickiewicza 30, 30-059 Krakow (Poland)

    2013-05-01

    The paper reports about a biomimetic based comparison of deformation in magnetron sputtered multilayer coatings based on titanium (Ti), titanium nitride (TiN) and diamond-like carbon (DLC) layers and the deformation mechanisms in nacre of mollusc shells. Nacre as highly mineralized tissue combines high stiffness and hardness with high toughness, enabling resistance to fracture and crack propagation during tensile loading. Such behaviour is based on a combination of load transmission by tensile stressed aragonite tablets and shearing in layers between the tablets. Shearing in these polysaccharide and protein interlayers demands hydrated conditions. Otherwise, nacre has similar brittle behaviour to aragonite. To prevent shear failure, shear hardening occurs by progressive tablet locking due to wavy dovetail-like surface geometry of the tablets. Similar effects by shearing and strain hardening mechanisms were found for Ti interlayers between TiN and DLC layers in high-resolution transmission electron microscopy studies, performed in deformed zones beneath spherical indentations. 7 nm thin Ti films are sufficient for strong toughening of the whole multi-layered coating structure, providing a barrier for propagation of cracks, starting from tensile-stressed, hard, brittle TiN or DLC layers. - Highlights: • Biomimetic approach to TiN-diamond-like carbon (DLC) multilayers by sputtering • Investigation of deformation in/around hardness indents by HR-TEM • Plastic deformation with shearing in 7-nm thick Ti interlayers in TiN–DLC multilayers • Biomimetically comparable to nacre deformation.

  15. Use of Synergistic Interactions to Fabricate Strong, Tough, and Conductive Artificial Nacre Based on Graphene Oxide and Chitosan.

    Science.gov (United States)

    Wan, Sijie; Peng, Jingsong; Li, Yuchen; Hu, Han; Jiang, Lei; Cheng, Qunfeng

    2015-10-27

    Graphene is the strongest and stiffest material, leading to the development of promising applications in many fields. However, the assembly of graphene nanosheets into macrosized nanocomposites for practical applications remains a challenge. Nacre in its natural form sets the "gold standard" for toughness and strength, which serves as a guide to the assembly of graphene nanosheets into high-performance nanocomposites. Here we show the strong, tough, conductive artificial nacre based on graphene oxide through synergistic interactions of hydrogen and covalent bonding. Tensile strength and toughness was 4 and 10 times higher, respectively, than that of natural nacre. The exceptional integrated strong and tough artificial nacre has promising applications in aerospace, artificial muscle, and tissue engineering, especially for flexible supercapacitor electrodes due to its high electrical conductivity. The use of synergistic interactions is a strategy for the development of high-performance nanocomposites.

  16. Identification of Proteins with Potential Osteogenic Activity Present in the Water-Soluble Matrix Proteins from Crassostrea gigas Nacre Using a Proteomic Approach

    Directory of Open Access Journals (Sweden)

    Daniel V. Oliveira

    2012-01-01

    Full Text Available Nacre, when implanted in vivo in bones of dogs, sheep, mice, and humans, induces a biological response that includes integration and osteogenic activity on the host tissue that seems to be activated by a set of proteins present in the nacre water-soluble matrix (WSM. We describe here an experimental approach that can accurately identify the proteins present in the WSM of shell mollusk nacre. Four proteins (three gigasin-2 isoforms and a cystatin A2 were for the first time identified in WSM of Crassostrea gigas nacre using 2DE and LC-MS/MS for protein identification. These proteins are thought to be involved in bone remodeling processes and could be responsible for the biocompatibility shown between bone and nacre grafts. These results represent a contribution to the study of shell biomineralization process and opens new perspectives for the development of new nacre biomaterials for orthopedic applications.

  17. Mercury concentration in bivalve molluscs

    Directory of Open Access Journals (Sweden)

    Szkoda Józef

    2015-09-01

    Full Text Available A total of 85 mussel samples of eight species were examined. Analysis of mercury in the freeze-dried samples was carried out by atomic absorption spectrometry method using direct mercury analyser AMA 254. The analytical procedure for determination of mercury was covered by the quality assurance programme of research and participation in national and international proficiency tests. Concentrations of total mercury in all investigated samples were found to be generally low, in the range of 0.033-0.577 mg/kg of dry weight and of 0.003-0.045 mg/kg of wet weight. The results indicate that obtained levels of mercury in bivalve molluscs are not likely to pose a risk to the health of consumers.

  18. Bio-Inspired nacre-like nanolignocellulose-poly (vinyl alcohol)-TiO2 composite with superior mechanical and photocatalytic properties.

    Science.gov (United States)

    Chen, Yipeng; Wang, Hanwei; Dang, Baokang; Xiong, Ye; Yao, Qiufang; Wang, Chao; Sun, Qingfeng; Jin, Chunde

    2017-05-12

    Nacre, the gold standard for biomimicry, provides an excellent example and guideline for assembling high-performance composites. Inspired by the layered structure and extraordinary strength and toughness of natural nacre, nacre-like nanolignocellulose/poly (vinyl alcohol)/TiO 2 composites possessed the similar layered structure of natural nacre were constructed through hot-pressing process. Poly (vinyl alcohol) and TiO 2 nanoparticles have been used as nanofillers to improve the mechanical performance and synchronously endow the superior photocatalytic activity of the composites. This research would be provided a promising candidate for the photooxidation of volatile organic compounds also combined with outstanding mechanical property.

  19. Nacre-inspired design of mechanical stable coating with underwater superoleophobicity.

    Science.gov (United States)

    Xu, Li-Ping; Peng, Jitao; Liu, Yibiao; Wen, Yongqiang; Zhang, Xueji; Jiang, Lei; Wang, Shutao

    2013-06-25

    Because of the frequent oil spill accidents in marine environment, stable superoleophobic coatings under seawater are highly desired. Current underwater superoleophobic surfaces often suffer from mechanical damages and lose their superoleophobicity gradually. It remains a challenge to fabricate a stable and robust underwater superoleophobic film which can endure harsh conditions in practical application. Nacre is one of most extensively studied rigid biological materials. Inspired by the outstanding mechanical property of seashell nacre and those underwater superoleophobic surfaces from nature, we fabricated a polyelectrolyte/clay hybrid film via typical layer-by-layer (LBL) method based on building blocks with high surface energy. 'Bricks-and-mortar' structure of seashell nacre was conceptually replicated into the prepared film, which endows the obtained film with excellent mechanical property and great abrasion resistance. In addtion, the prepared film also exhibits stable underwater superoleophobicity, low oil adhesion, and outstanding environment durability in artificial seawater. We anticipate that this work will provide a new method to design underwater low-oil-adhesion film with excellent mechanical property and improved stability, which may advance the practical applications in marine antifouling and microfluidic devices.

  20. Flexible digestion strategies and trace metal assimilation in marine bivalves

    Science.gov (United States)

    Decho, Alan W.; Luoma, Samuel N.

    1996-01-01

    Pulse-chase experiments show that two marine bivalves take optimal advantage of different types of particulate food by varying food retention time in a flexible two-phase digestive system. For example, carbon is efficiently assimilated from bacteria by subjecting nearly all the ingested bacteria to prolonged digestion. Prolonging digestion also enhances assimilation of metals, many of which are toxic in minute quantities if they are biologically available. Detritus-feeding aquatic organisms have always lived in environments naturally rich in particle-reactive metals. We suggest that avoiding excess assimilation of metals could be a factor in the evolution of digestion strategies. We tested that suggestion by studying digestion of particles containing different Cr concentrations. We show that bivalves are capable of modifying the digestive processing of food to reduce exposure to high, biologically available, Cr concentrations. The evolution of a mechanism in some species to avoid high concentrations of metals in food could influence how effects of modern metal pollution are manifested in marine ecosystems.

  1. Microplastics in commercial bivalves from China

    International Nuclear Information System (INIS)

    Li, Jiana; Yang, Dongqi; Li, Lan; Jabeen, Khalida; Shi, Huahong

    2015-01-01

    We investigated microplastic pollution in 9 commercial bivalves from a fishery market in China. Multiple types of microplastics, including fibers, fragments and pellets, occurred in the tissue of all bivalves. The number of total microplastics varied from 2.1 to 10.5 items/g and from 4.3 to 57.2 items/individual for bivalves. Scapharca subcrenata contained on average 10.5 items/g and exhibited the highest levels of microplastics by weight. Fibers were the most common microplastics and consisted of more than half of the total microplastics in each of the 8 species. In Alectryonella plicatula, pellets accounted for 60% of the total microplastics. The most common size class was less than 250 μm and accounted for 33–84% of the total microplastics calculated by species. Our results suggest that microplastic pollution was widespread and exhibited a relatively high level in commercial bivalves from China. More intensive investigations on microplastics should be conducted in seafood. - Highlights: • Fiber, fragment and pellet microplastics were found in 9 bivalves. • The abundance of microplastics was 2.1–10.5 items/g. • Fibers were the most common microplastics. • The most common size class of microplastics was less than 250 μm. • Microplastic pollution was widespread and serious in commercial bivalves. - Fiber, fragment and pellet microplastics in the range of 2.1–10.5 items/g were observed in 9 species of commercially popular bivalves from China.

  2. Morphology, Structure of Dimorphic Sperm, and Reproduction in the Hermaphroditic Commensal Bivalve Pseudopythina tsurumaru (Galeommatoidea: Kellidae)

    DEFF Research Database (Denmark)

    Lützen, Jørgen; Jespersen, Åse; Takahashi, Tohru

    2004-01-01

    Galeommatoide, commensal bivalve, reproduction, dimorphic sperm, sperm ultrastructure, spermatozeugma......Galeommatoide, commensal bivalve, reproduction, dimorphic sperm, sperm ultrastructure, spermatozeugma...

  3. Bioinspired Hierarchical Alumina-Graphene Oxide-Poly(vinyl alcohol) Artificial Nacre with Optimized Strength and Toughness.

    Science.gov (United States)

    Wang, Jinrong; Qiao, Jinliang; Wang, Jianfeng; Zhu, Ying; Jiang, Lei

    2015-05-06

    Due to hierarchical organization of micro- and nanostructures, natural nacre exhibits extraordinary strength and toughness, and thus provides a superior model for the design and fabrication of high-performance artificial composite materials. Although great progress has been made in constructing layered composites by alternately stacking hard inorganic platelets and soft polymers, the real issue is that the excellent strength of these composites was obtained at the sacrifice of toughness. In this work, inspired by the layered aragonite microplatelets/chitin nanofibers-protein structure of natural nacre, alumina microplatelets-graphene oxide nanosheets-poly(vinyl alcohol) (Al2O3/GO-PVA) artificial nacre is successfully constructed through layer-by-layer bottom-up assembly, in which Al2O3 and GO-PVA act as "bricks" and "mortar", respectively. The artificial nacre has hierarchical "brick-and-mortar" structure and exhibits excellent strength (143 ± 13 MPa) and toughness (9.2 ± 2.7 MJ/m(3)), which are superior to those of natural nacre (80-135 MPa, 1.8 MJ/m(3)). It was demonstrated that the multiscale hierarchical structure of ultrathin GO nanosheets and submicrometer-thick Al2O3 platelets can deal with the conflict between strength and toughness, thus leading to the excellent mechanical properties that cannot be obtained using only one size of platelet. We strongly believe that the work presented here provides a creative strategy for designing and developing new composites with excellent strength and toughness.

  4. Artificial nacre-like papers based on noncovalent functionalized boron nitride nanosheets with excellent mechanical and thermally conductive properties

    Science.gov (United States)

    Zeng, Xiaoliang; Ye, Lei; Yu, Shuhui; Li, Hao; Sun, Rong; Xu, Jianbin; Wong, Ching-Ping

    2015-04-01

    Inspired by the nano/microscale hierarchical structure and the precise inorganic/organic interface of natural nacre, we fabricated artificial nacre-like papers based on noncovalent functionalized boron nitride nanosheets (NF-BNNSs) and poly(vinyl alcohol) (PVA) via a vacuum-assisted self-assembly technique. The artificial nacre-like papers exhibit excellent tensile strength (125.2 MPa), on a par with that of the natural nacre, and moreover display a 30% higher toughness (2.37 MJ m-3) than that of the natural nacre. These excellent mechanical properties result from an ordered `brick-and-mortar' arrangement of NF-BNNSs and PVA, in which the long-chain PVA molecules act as the bridge to link NF-BNNSs via hydrogen bonds. The resulting papers also render high thermal conductivity (6.9 W m-1 K-1), and reveal their superiority as flexible substrates to support light-emitting-diode chips. The combined mechanical and thermal properties make the materials highly desirable as flexible substrates for next-generation commercial portable electronics.Inspired by the nano/microscale hierarchical structure and the precise inorganic/organic interface of natural nacre, we fabricated artificial nacre-like papers based on noncovalent functionalized boron nitride nanosheets (NF-BNNSs) and poly(vinyl alcohol) (PVA) via a vacuum-assisted self-assembly technique. The artificial nacre-like papers exhibit excellent tensile strength (125.2 MPa), on a par with that of the natural nacre, and moreover display a 30% higher toughness (2.37 MJ m-3) than that of the natural nacre. These excellent mechanical properties result from an ordered `brick-and-mortar' arrangement of NF-BNNSs and PVA, in which the long-chain PVA molecules act as the bridge to link NF-BNNSs via hydrogen bonds. The resulting papers also render high thermal conductivity (6.9 W m-1 K-1), and reveal their superiority as flexible substrates to support light-emitting-diode chips. The combined mechanical and thermal properties make

  5. Fishnet model for failure probability tail of nacre-like imbricated lamellar materials

    Science.gov (United States)

    Luo, Wen; Bažant, Zdeněk P.

    2017-12-01

    Nacre, the iridescent material of the shells of pearl oysters and abalone, consists mostly of aragonite (a form of CaCO3), a brittle constituent of relatively low strength (≈10 MPa). Yet it has astonishing mean tensile strength (≈150 MPa) and fracture energy (≈350 to 1,240 J/m2). The reasons have recently become well understood: (i) the nanoscale thickness (≈300 nm) of nacre's building blocks, the aragonite lamellae (or platelets), and (ii) the imbricated, or staggered, arrangement of these lamellea, bound by biopolymer layers only ≈25 nm thick, occupying engineering applications, however, the failure probability of ≤10‑6 is generally required. To guarantee it, the type of probability density function (pdf) of strength, including its tail, must be determined. This objective, not pursued previously, is hardly achievable by experiments alone, since >10^8 tests of specimens would be needed. Here we outline a statistical model of strength that resembles a fishnet pulled diagonally, captures the tail of pdf of strength and, importantly, allows analytical safety assessments of nacreous materials. The analysis shows that, in terms of safety, the imbricated lamellar structure provides a major additional advantage—˜10% strength increase at tail failure probability 10^‑6 and a 1 to 2 orders of magnitude tail probability decrease at fixed stress. Another advantage is that a high scatter of microstructure properties diminishes the strength difference between the mean and the probability tail, compared with the weakest link model. These advantages of nacre-like materials are here justified analytically and supported by millions of Monte Carlo simulations.

  6. Travel report Mauritania bivalve Molluscs october 2008

    NARCIS (Netherlands)

    Poelman, M.

    2008-01-01

    During the last four years Mauritania has been working on the completion of a Food Safety Program of Bivalve Mollusks, in order to obtain an export approval by the Europe Union. During the preparations for an inspection by the FVO (Food and Veterinary Office) no fisheries or production activities

  7. Microplastics in commercial bivalves from China.

    Science.gov (United States)

    Li, Jiana; Yang, Dongqi; Li, Lan; Jabeen, Khalida; Shi, Huahong

    2015-12-01

    We investigated microplastic pollution in 9 commercial bivalves from a fishery market in China. Multiple types of microplastics, including fibers, fragments and pellets, occurred in the tissue of all bivalves. The number of total microplastics varied from 2.1 to 10.5 items/g and from 4.3 to 57.2 items/individual for bivalves. Scapharca subcrenata contained on average 10.5 items/g and exhibited the highest levels of microplastics by weight. Fibers were the most common microplastics and consisted of more than half of the total microplastics in each of the 8 species. In Alectryonella plicatula, pellets accounted for 60% of the total microplastics. The most common size class was less than 250 μm and accounted for 33-84% of the total microplastics calculated by species. Our results suggest that microplastic pollution was widespread and exhibited a relatively high level in commercial bivalves from China. More intensive investigations on microplastics should be conducted in seafood. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Bivalves: From individual to population modelling

    NARCIS (Netherlands)

    Saraiva, S.; van der Meer, J.; Kooijman, S.A.L.M.

    2014-01-01

    An individual based population model for bivalves was designed, built and tested in a 0D approach, to simulate the population dynamics of a mussel bed located in an intertidal area. The processes at the individual level were simulated following the dynamic energy budget theory, whereas initial egg

  9. Bivalve grazing can shape phytoplankton communities

    Science.gov (United States)

    Lucas, Lisa; Cloern, James E.; Thompson, Janet K.; Stacey, Mark T.; Koseff, Jeffrey K.

    2016-01-01

    The ability of bivalve filter feeders to limit phytoplankton biomass in shallow waters is well-documented, but the role of bivalves in shaping phytoplankton communities is not. The coupled effect of bivalve grazing at the sediment-water interface and sinking of phytoplankton cells to that bottom filtration zone could influence the relative biomass of sinking (diatoms) and non-sinking phytoplankton. Simulations with a pseudo-2D numerical model showed that benthic filter feeding can interact with sinking to alter diatom:non-diatom ratios. Cases with the smallest proportion of diatom biomass were those with the fastest sinking speeds and strongest bivalve grazing rates. Hydrodynamics modulated the coupled sinking-grazing influence on phytoplankton communities. For example, in simulations with persistent stratification, the non-sinking forms accumulated in the surface layer away from bottom grazers while the sinking forms dropped out of the surface layer toward bottom grazers. Tidal-scale stratification also influenced vertical gradients of the two groups in opposite ways. The model was applied to Suisun Bay, a low-salinity habitat of the San Francisco Bay system that was transformed by the introduction of the exotic clam Potamocorbula amurensis. Simulation results for this Bay were similar to (but more muted than) those for generic habitats, indicating that P. amurensis grazing could have caused a disproportionate loss of diatoms after its introduction. Our model simulations suggest bivalve grazing affects both phytoplankton biomass and community composition in shallow waters. We view these results as hypotheses to be tested with experiments and more complex modeling approaches.

  10. Theoretical characterization of a model of aragonite crystal orientation in red abalone nacre

    International Nuclear Information System (INIS)

    Coppersmith, S N; Gilbert, P U P A; Metzler, R A

    2009-01-01

    Nacre, commonly known as mother-of-pearl, is a remarkable biomineral that in red abalone consists of layers of 400 nm thick aragonite crystalline tablets confined by organic matrix sheets, with the [0 0 1] crystal axes of the aragonite tablets oriented to within ±12 deg. from the normal to the layer planes. Recent experiments demonstrate that greater orientational order develops over a distance of tens of layers from the prismatic boundary at which nacre formation begins. Our previous simulations of a model in which the order develops because of differential tablet growth rates (oriented tablets growing faster than misoriented ones) yield patterns of tablets that agree qualitatively and quantitatively with the experimental measurements. This paper presents an analytical treatment of this model, focusing on how the dynamical development and eventual degree of order depend on model parameters. Dynamical equations for the probability distributions governing tablet orientations are introduced whose form can be determined from symmetry considerations and for which substantial analytic progress can be made. Numerical simulations are performed to relate the parameters used in the analytic theory to those in the microscopic growth model. The analytic theory demonstrates that the dynamical mechanism is able to achieve a much higher degree of order than naive estimates would indicate

  11. Direct and indirect effects of biological factors on extinction risk in fossil bivalves.

    Science.gov (United States)

    Harnik, Paul G

    2011-08-16

    Biological factors, such as abundance and body size, may contribute directly to extinction risk and indirectly through their influence on other biological characteristics, such as geographic range size. Paleontological data can be used to explicitly test many of these hypothesized relationships, and general patterns revealed through analysis of the fossil record can help refine predictive models of extinction risk developed for extant species. Here, I use structural equation modeling to tease apart the contributions of three canonical predictors of extinction--abundance, body size, and geographic range size--to the duration of bivalve species in the early Cenozoic marine fossil record of the eastern United States. I find that geographic range size has a strong direct effect on extinction risk and that an apparent direct effect of abundance can be explained entirely by its covariation with geographic range. The influence of geographic range on extinction risk is manifest across three ecologically disparate bivalve clades. Body size also has strong direct effects on extinction risk but operates in opposing directions in different clades, and thus, it seems to be decoupled from extinction risk in bivalves as a whole. Although abundance does not directly predict extinction risk, I reveal weak indirect effects of both abundance and body size through their positive influence on geographic range size. Multivariate models that account for the pervasive covariation between biological factors and extinction are necessary for assessing causality in evolutionary processes and making informed predictions in applied conservation efforts.

  12. Bioinspired Interface Engineering for Moisture Resistance in Nacre-Mimetic Cellulose Nanofibrils/Clay Nanocomposites.

    Science.gov (United States)

    Yao, Kun; Huang, Shu; Tang, Hu; Xu, Yeping; Buntkowsky, Gerd; Berglund, Lars A; Zhou, Qi

    2017-06-14

    The interfacial adhesion design between "mortar" and "bricks" is essential for mechanical and barrier performance of nanocellulose-based nacre-mimetic nanocomposites, especially at high moisture conditions. To address this fundamental challenge, dopamine (DA) has been conjugated to cellulose nanofibrils (CNFs) and subsequently assembled with montmorillonite (MTM) to generate layered nanocomposite films inspired by the strong adhesion of mussel adhesive proteins to inorganic surfaces under water. The selective formation of catechol/metal ion chelation and hydrogen bonding at the interface between MTM platelets and CNFs bearing DA renders transparent films with strong mechanical properties, particularly at high humidity and in wet state. Increasing the amount of conjugated DA on CNFs results in nanocomposites with increased tensile strength and modulus, up to 57.4 MPa and 1.1 GPa, respectively, after the films are swollen in water. The nanocomposites also show excellent gas barrier properties at high relative humidity (95%), complementing the multifunctional property profile.

  13. High Performances of Artificial Nacre-Like Graphene Oxide-Carrageenan Bio-Nanocomposite Films

    Directory of Open Access Journals (Sweden)

    Wenkun Zhu

    2017-05-01

    Full Text Available This study was inspired by the unique multi-scale and multi-level ‘brick-and-mortar’ (B&M structure of nacre layers. We prepared the B&M, environmentally-friendly graphene oxide-carrageenan (GO-Car nanocomposite films using the following steps. A natural polyhydroxy polymer, carrageenan, was absorbed on the surface of monolayer GO nanosheets through hydrogen-bond interactions. Following this, a GO-Car hybridized film was produced through a natural drying process. We conducted structural characterization in addition to analyzing mechanical properties and cytotoxicity of the films. Scanning electron microscope (SEM and X-ray diffraction (XRD analyses showed that the nanocomposite films had a similar morphology and structure to nacre. Furthermore, the results from Fourier transform infrared spectroscopy (FT-IR, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS and Thermogravimetric (TG/DTG were used to explain the GO-Car interaction. Analysis from static mechanical testers showed that GO-Car had enhanced Young’s modulus, maximum tensile strength and breaking elongation compared to pure GO. The GO-Car nanocomposite films, containing 5% wt. of Car, was able to reach a tensile strength of 117 MPa. The biocompatibility was demonstrated using a RAW264.7 cell test, with no significant alteration found in cellular morphology and cytotoxicity. The preparation process for GO-Car films is simple and requires little time, with GO-Car films also having favorable biocompatibility and mechanical properties. These advantages make GO-Car nanocomposite films promising materials in replacing traditional petroleum-based plastics and tissue engineering-oriented support materials.

  14. Role of the polymer phase in the mechanics of nacre-like composites

    Science.gov (United States)

    Niebel, Tobias P.; Bouville, Florian; Kokkinis, Dimitri; Studart, André R.

    2016-11-01

    Although strength and toughness are often mutually exclusive properties in man-made structural materials, nature is full of examples of composite materials that combine these properties in a remarkable way through sophisticated multiscale architectures. Understanding the contributions of the different constituents to the energy dissipating toughening mechanisms active in these natural materials is crucial for the development of strong artificial composites with a high resistance to fracture. Here, we systematically study the influence of the polymer properties on the mechanics of nacre-like composites containing an intermediate fraction of mineral phase (57 vol%). To this end, we infiltrate ceramic scaffolds prepared by magnetically assisted slip casting (MASC) with monomers that are subsequently cured to yield three drastically different polymers: (i) poly(lauryl methacrylate) (PLMA), a soft and weak elastomer; (ii) poly(methyl methacrylate) (PMMA), a strong, stiff and brittle thermoplastic; and (iii) polyether urethane diacrylate-co-poly(2-hydroxyethyl methacrylate) (PUA-PHEMA), a tough polymer of intermediate strength and stiffness. By combining our experimental data with finite element modeling, we find that stiffer polymers can increase the strength of the composite by reducing stress concentrations in the inorganic scaffold. Moreover, infiltrating the scaffolds with tough polymers leads to composites with high crack initiation toughness KIC. An organic phase with a minimum strength and toughness is also required to fully activate the mechanisms programmed within the ceramic structure for a rising R-curve behavior. Our results indicate that a high modulus of toughness is a key parameter for the selection of polymers leading to strong and tough bioinspired nacre-like composites.

  15. Artificially evolved functional shell morphology of burrowing bivalves

    DEFF Research Database (Denmark)

    Germann, D. P.; Schatz, W.; Hotz, Peter Eggenberger

    2014-01-01

    The morphological evolution of bivalves is documented by a rich fossil record. It is believed that the shell shape and surface sculpture play an important role for the burrowing performance of endobenthic species. While detailed morphometric studies of bivalve shells have been done, there are alm...

  16. Bio-inspired nacre-like composite films based on graphene with superior mechanical, electrical, and biocompatible properties.

    Science.gov (United States)

    Li, Yuan-Qing; Yu, Ting; Yang, Tian-Yi; Zheng, Lian-Xi; Liao, Kin

    2012-07-03

    Bio-inspired multifunctional composite films based on reduced poly(vinyl alcohol)/graphene oxide (R-PVA/GO) layers are prepared by a facile solution casting method followed by a reduction procedure. The resulting films with nacre-like, bricks-and-mortar microstructure have excellent mechanical properties, electrical conductivity, and biocompatibility. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Cambrian bivalved arthropod reveals origin of arthrodization

    Science.gov (United States)

    Legg, David A.; Sutton, Mark D.; Edgecombe, Gregory D.; Caron, Jean-Bernard

    2012-01-01

    Extant arthropods are diverse and ubiquitous, forming a major constituent of most modern ecosystems. Evidence from early Palaeozoic Konservat Lagerstätten indicates that this has been the case since the Cambrian. Despite this, the details of arthropod origins remain obscure, although most hypotheses regard the first arthropods as benthic predators or scavengers such as the fuxianhuiids or megacheirans (‘great-appendage’ arthropods). Here, we describe a new arthropod from the Tulip Beds locality of the Burgess Shale Formation (Cambrian, series 3, stage 5) that possesses a weakly sclerotized thorax with filamentous appendages, encased in a bivalved carapace, and a strongly sclerotized, elongate abdomen and telson. A cladistic analysis resolved this taxon as the basal-most member of a paraphyletic grade of nekto-benthic forms with bivalved carapaces. This grade occurs at the base of Arthropoda (panarthropods with arthropodized trunk limbs) and suggests that arthrodization (sclerotization and jointing of the exoskeleton) evolved to facilitate swimming. Predatory and fully benthic habits evolved later in the euarthropod stem-lineage and are plesiomorphically retained in pycnogonids (sea spiders) and euchelicerates (horseshoe crabs and arachnids). PMID:23055069

  18. Lithium Insertion in LiCr3O8, NaCr3O8, and KCr3O8 at Room Temperature and at 125°C

    DEFF Research Database (Denmark)

    Koksbang, R.; Fauteux, D.; Norby, P.

    1989-01-01

    . At elevated temperatures, the isostructural compounds NaCr3O8 and KCr3O8 are able to accommodate morethan 4Li/MCr3O8. During this process, minor structural changes are observed. At room temperature, NaCr3O8 and KCr3O8also accommodate Li topotactically, but the maximum number of Li inserted per formula...

  19. Artificially evolved functional shell morphology of burrowing bivalves

    DEFF Research Database (Denmark)

    Germann, D. P.; Schatz, W.; Hotz, Peter Eggenberger

    2014-01-01

    The morphological evolution of bivalves is documented by a rich fossil record. It is believed that the shell shape and surface sculpture play an important role for the burrowing performance of endobenthic species. While detailed morphometric studies of bivalve shells have been done...... dimensional (3D) objects, the first ever artificial evolution of a physical bivalve shell was performed. The result was a vertically flattened shell occupying only the top sediment layers. Insufficient control of the sediment was the major limitation of the setup and restricted the significance of the results...

  20. Nacre-like hybrid films: Structure, properties, and the effect of relative humidity.

    Science.gov (United States)

    Abba, Mohammed T; Hunger, Philipp M; Kalidindi, Surya R; Wegst, Ulrike G K

    2015-03-01

    Functional materials often are hybrids composed of biopolymers and mineral constituents. The arrangement and interactions of the constituents frequently lead to hierarchical structures with exceptional mechanical properties and multifunctionality. In this study, hybrid thin films with a nacre-like brick-and-mortar microstructure were fabricated in a straightforward and reproducible manner through manual shear casting using the biopolymer chitosan as the matrix material (mortar) and alumina platelets as the reinforcing particles (bricks). The ratio of inorganic to organic content was varied from 0% to 15% and the relative humidities from 36% to 75% to determine their effects on the mechanical properties. It was found that increasing the volume fraction of alumina from 0% to 15% results in a twofold increase in the modulus of the film, but decreases the tensile strength by up to 30%, when the volume fraction of alumina is higher than 5%. Additionally, this study quantifies and illustrates the critical role of the relative humidity on the mechanical properties of the hybrid film. Increasing the relative humidity from 36% to 75% decreases the modulus and strength by about 45% and triples the strain at failure. These results suggest that complex hybrid materials can be manufactured and tailor made for specific applications or environmental conditions. Copyright © 2015. Published by Elsevier Ltd.

  1. Extreme Mechanical Behavior of Nacre-Mimetic Graphene-Oxide and Silk Nanocomposites.

    Science.gov (United States)

    Xie, Wanting; Tadepalli, Sirimuvva; Park, Sang Hyun; Kazemi-Moridani, Amir; Jiang, Qisheng; Singamaneni, Srikanth; Lee, Jae-Hwang

    2018-02-14

    Biological materials have the ability to withstand extreme mechanical forces due to their unique multilevel hierarchical structure. Here, we fabricated a nacre-mimetic nanocomposite comprised of silk fibroin and graphene oxide that exhibits hybridized dynamic responses arising from alternating high-contrast mechanical properties of the components at the nanoscale. Dynamic mechanical behavior of these nanocomposites is assessed through a microscale ballistic characterization using a 7.6 μm diameter silica sphere moving at a speed of approximately 400 m/s. The volume fraction of graphene oxide in these composites is systematically varied from 0 to 32 vol % to quantify the dynamic effects correlating with the structural morphologies of the graphene oxide flakes. Specific penetration energy of the films rapidly increases as the distribution of graphene oxide flakes evolves from noninteracting, isolated sheets to a partially overlapping continuous sheet. The specific penetration energy of the nanocomposite at the highest graphene oxide content tested here is found to be significantly higher than that of Kevlar fabrics and close to that of pure multilayer graphene. This study evidently demonstrates that the morphologies of nanoscale constituents and their interactions are critical to realize scalable high-performance nanocomposites using typical nanomaterial constituents having finite dimensions.

  2. Cryptosporidium species from common edible bivalves in Manila Bay, Philippines.

    Science.gov (United States)

    Pagoso, Edison Jay A; Rivera, Windell L

    2017-06-15

    Manila Bay is one of the major propagation sites of edible bivalves in the Philippines. Studies have shown that bivalves might be contaminated with human pathogens like the protozoan parasite Cryptosporidium, one of the major causes of gastroenteritis in the world. In this study, Cryptosporidium from four species of edible bivalves were isolated using a combination of sucrose flotation and immunomagnetic separation. Using direct fluorescent antibody test, Cryptosporidium oocysts were found in 67 out of 144 samples collected. DNA sequence analysis of the 18S rRNA gene of the isolates detected C. parvum and C. hominis (major causes of human cryptosporidiosis) and C. meleagridis (causes infection in avian species). Analysis of the 60kDa glycoprotein gene further confirmed the genotypes of the Cryptosporidium isolates. This study is the first to provide baseline information on Cryptosporidium contamination of Manila Bay where bivalves are commonly cultured. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Physiology and the mariculture of some northeastern Pacific bivalve molluscs

    National Research Council Canada - National Science Library

    Bernard, F. R

    1983-01-01

    Equations describing the effects of water temperature, salinity, oxygen, and food availability on ventilation and oxygen consumption rates of nine species of bivalve molluscs from the Oregonian Province are given...

  4. Microbial Diseases of Bivalve Mollusks: Infections, Immunology and Antimicrobial Defense.

    Science.gov (United States)

    Zannella, Carla; Mosca, Francesco; Mariani, Francesca; Franci, Gianluigi; Folliero, Veronica; Galdiero, Marilena; Tiscar, Pietro Giorgio; Galdiero, Massimiliano

    2017-06-17

    A variety of bivalve mollusks (phylum Mollusca, class Bivalvia) constitute a prominent commodity in fisheries and aquacultures, but are also crucial in order to preserve our ecosystem's complexity and function. Bivalve mollusks, such as clams, mussels, oysters and scallops, are relevant bred species, and their global farming maintains a high incremental annual growth rate, representing a considerable proportion of the overall fishery activities. Bivalve mollusks are filter feeders; therefore by filtering a great quantity of water, they may bioaccumulate in their tissues a high number of microorganisms that can be considered infectious for humans and higher vertebrates. Moreover, since some pathogens are also able to infect bivalve mollusks, they are a threat for the entire mollusk farming industry. In consideration of the leading role in aquaculture and the growing financial importance of bivalve farming, much interest has been recently devoted to investigate the pathogenesis of infectious diseases of these mollusks in order to be prepared for public health emergencies and to avoid dreadful income losses. Several bacterial and viral pathogens will be described herein. Despite the minor complexity of the organization of the immune system of bivalves, compared to mammalian immune systems, a precise description of the different mechanisms that induce its activation and functioning is still missing. In the present review, a substantial consideration will be devoted in outlining the immune responses of bivalves and their repertoire of immune cells. Finally, we will focus on the description of antimicrobial peptides that have been identified and characterized in bivalve mollusks. Their structural and antimicrobial features are also of great interest for the biotechnology sector as antimicrobial templates to combat the increasing antibiotic-resistance of different pathogenic bacteria that plague the human population all over the world.

  5. The growth rates and population dynamics of bivalves in estuaries ...

    African Journals Online (AJOL)

    Studies on bivalves in the SwartkOps estuary have indicated that spatfall oa::an dlD'iDllate summer. After adult populations had been decimated by floods in 1971 spat IDII.de up a Iarp proportion of the bivalve population in 1973. Growth rata! vary at difl"erent intertidallevela and in difl"erent parts of the estuary and growth ...

  6. Study of the effects of gamma sterilization on a bio material potential bone substitute: the nacre of Pinctada radiata (Leach, 1814)

    International Nuclear Information System (INIS)

    Ben Ammar, Rim

    2010-01-01

    In this work, we studied the effects of gamma irradiation at a dose of 25 kGy on physico-chemical properties of the nacre of the pearl oyster P. radiata Tunisian coast. The aim of our work is, after sterilizing the shell to gamma radiation, the study of its crystal structure, behavior and thermodynamics of the qualitative and quantitative composition of organic and inorganic matrices and compare them with those of the non-irradiated pearl . In addition, there has been interest in developing the method of sterilization with gamma irradiation to 25 kGy of the nacre of the pearl oyster Pinctada radiata.

  7. Co-option of bacteriophage lysozyme genes by bivalve genomes.

    Science.gov (United States)

    Ren, Qian; Wang, Chunyang; Jin, Min; Lan, Jiangfeng; Ye, Ting; Hui, Kaimin; Tan, Jingmin; Wang, Zheng; Wyckoff, Gerald J; Wang, Wen; Han, Guan-Zhu

    2017-01-01

    Eukaryotes have occasionally acquired genetic material through horizontal gene transfer (HGT). However, little is known about the evolutionary and functional significance of such acquisitions. Lysozymes are ubiquitous enzymes that degrade bacterial cell walls. Here, we provide evidence that two subclasses of bivalves (Heterodonta and Palaeoheterodonta) acquired a lysozyme gene via HGT, building on earlier findings. Phylogenetic analyses place the bivalve lysozyme genes within the clade of bacteriophage lysozyme genes, indicating that the bivalves acquired the phage-type lysozyme genes from bacteriophages, either directly or through intermediate hosts. These bivalve lysozyme genes underwent dramatic structural changes after their co-option, including intron gain and fusion with other genes. Moreover, evidence suggests that recurrent gene duplication occurred in the bivalve lysozyme genes. Finally, we show the co-opted lysozymes exhibit a capacity for antibacterial action, potentially augmenting the immune function of related bivalves. This represents an intriguing evolutionary strategy in the eukaryote-microbe arms race, in which the genetic materials of bacteriophages are co-opted by eukaryotes, and then used by eukaryotes to combat bacteria, using a shared weapon against a common enemy. © 2017 The Authors.

  8. Unique morphology and gradient arrangement of nacre's platelets in green mussel shells

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Jun; Zhang, Gangsheng, E-mail: zhanggs@gxu.edu.cn

    2015-07-01

    Nacre has long served as a classic model in biomineralization and the synthesis of biomimetic materials. However, the morphology and arrangement of its basic building blocks, the aragonite platelets, are still under hot debate. In this study, using a field emission scanning electron microscope (SEM), a high-resolution transmission electron microscope (HRTEM), and an X-ray diffractometer (XRD), we investigate the platelets at the edges and centers of green mussel shells. We find that 1) flat and curved platelets coexist in green mussel shells; 2) the immature platelets at the shell edge are aggregates of aragonite nanoparticles, whereas the immature ones at the shell center are single crystals; and 3) the morphology and thickness of the platelets exhibit a gradient arrangement. Based on these findings, we hypothesize that the gradient in the thickness and curvature of the platelets may probably result from the difference in growth rate between the edge and the center of the shell and from the gradient in compressive stress imposed by the closing of the shells by the adductor muscles or the withdrawal of the periostracum by the mantle. We expect that the presented results will shed new light on the formation mechanisms of natural composite materials. - Highlights: • Flat and curved platelets coexist in green mussel shells. • The immature platelets at the shell edge consist of aragonite nanoparticles. • The immature platelets at the shell center are single crystals. • The morphology and thickness of platelets exhibit a gradient arrangement. • The gradient arrangement of platelets may result from the stress gradient.

  9. Shear Strength and Interfacial Toughness Characterization of Sapphire-Epoxy Interfaces for Nacre-Inspired Composites.

    Science.gov (United States)

    Behr, Sebastian; Jungblut, Laura; Swain, Michael V; Schneider, Gerold A

    2016-10-12

    The common tensile lap-shear test for adhesive joints is inappropriate for brittle substrates such as glasses or ceramics where stress intensifications due to clamping and additional bending moments invalidate results. Nevertheless, bonding of glasses and ceramics is still important in display applications for electronics, in safety glass and ballistic armor, for dental braces and restoratives, or in recently developed bioinspired composites. To mechanically characterize adhesive bondings in these fields nonetheless, a novel approach based on the so-called Schwickerath test for dental sintered joints is used. This new method not only matches data from conventional analysis but also uniquely combines the accurate determination of interfacial shear strength and toughness in one simple test. The approach is verified for sapphire-epoxy joints that are of interest for bioinspired composites. For these, the procedure not only provides quantitative interfacial properties for the first time, it also exemplarily suggests annealing of sapphire at 1000 °C for 10 h for mechanically and economically effective improvements of the interfacial bond strength and toughness. With increases of strength and toughness from approximately 8 to 29 MPa and from 2.6 to 35 J/m 2 , respectively, this thermal modification drastically enhances the properties of unmodified sapphire-epoxy interfaces. At the same time, it is much more convenient than wet-chemical approaches such as silanization. Hence, besides the introduction of a new testing procedure for adhesive joints of brittle or expensive substrates, a new and facile annealing process for improvements of the adhesive properties of sapphire is suggested and quantitative data for the mechanical properties of sapphire-epoxy interfaces that are common in synthetic nacre-inspired composites are provided for the first time.

  10. Microplastics in bivalves cultured for human consumption.

    Science.gov (United States)

    Van Cauwenberghe, Lisbeth; Janssen, Colin R

    2014-10-01

    Microplastics are present throughout the marine environment and ingestion of these plastic particles (microplastics in two species of commercially grown bivalves: Mytilus edulis and Crassostrea gigas. Microplastics were recovered from the soft tissues of both species. At time of human consumption, M. edulis contains on average 0.36 ± 0.07 particles g(-1) (wet weight), while a plastic load of 0.47 ± 0.16 particles g(-1) ww was detected in C. gigas. As a result, the annual dietary exposure for European shellfish consumers can amount to 11,000 microplastics per year. The presence of marine microplastics in seafood could pose a threat to food safety, however, due to the complexity of estimating microplastic toxicity, estimations of the potential risks for human health posed by microplastics in food stuffs is not (yet) possible. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Comparative analysis of the transcriptome in tissues secreting purple and white nacre in the pearl mussel Hyriopsis cumingii.

    Directory of Open Access Journals (Sweden)

    Zhiyi Bai

    Full Text Available The triangle sail mussel Hyriopsis cumingii (Lea is the most important mussel species used for commercial freshwater pearl production in China. Mussel color is an important indicator of pearl quality. To identify genes involved in the nacre coloring, we conducted RNA-seq and obtained 541,268 sequences (298 bp average size and 440,034 sequences (293 bp average size in secreting purple and white nacre libraries (P- and W-libraries, respectively. The 981,302 Expressed Sequence Tags (ESTs were assembled into 47,812 contigs and 289,386 singletons. In BLASTP searches of the deduced protein, 22,495 were proteins with functional annotations. Thirty-three genes involved in pearl or shell formation were identified. Digital expression analysis identified a total of 358 differentially expressed genes, and 137 genes in the P-library and 221 genes in the W-library showed significantly higher expression. Furthermore, a set of SSR motifs and SNPs between the two samples was identified from the ESTs, which provided the markers for genetic linkage, QTL analysis and future breeding. These EST sequences provided valuable information to further understand the molecular mechanisms involved in the formation, color determination and evolution of the pearl or shell.

  12. Comparative Analysis of the Transcriptome in Tissues Secreting Purple and White Nacre in the Pearl Mussel Hyriopsis cumingii

    Science.gov (United States)

    Lin, Jingyun; Wang, Guiling; Li, Jiale

    2013-01-01

    The triangle sail mussel Hyriopsis cumingii (Lea) is the most important mussel species used for commercial freshwater pearl production in China. Mussel color is an important indicator of pearl quality. To identify genes involved in the nacre coloring, we conducted RNA-seq and obtained 541,268 sequences (298 bp average size) and 440,034 sequences (293 bp average size) in secreting purple and white nacre libraries (P- and W-libraries), respectively. The 981,302 Expressed Sequence Tags (ESTs) were assembled into 47,812 contigs and 289,386 singletons. In BLASTP searches of the deduced protein, 22,495 were proteins with functional annotations. Thirty-three genes involved in pearl or shell formation were identified. Digital expression analysis identified a total of 358 differentially expressed genes, and 137 genes in the P-library and 221 genes in the W-library showed significantly higher expression. Furthermore, a set of SSR motifs and SNPs between the two samples was identified from the ESTs, which provided the markers for genetic linkage, QTL analysis and future breeding. These EST sequences provided valuable information to further understand the molecular mechanisms involved in the formation, color determination and evolution of the pearl or shell. PMID:23341956

  13. Detection and molecular characterization of betanodaviruses retrieved from bivalve molluscs.

    Science.gov (United States)

    Volpe, E; Grodzki, M; Panzarin, V; Guercio, A; Purpari, G; Serratore, P; Ciulli, S

    2018-04-01

    Betanodaviruses are small ssRNA viruses responsible for viral encephalopathy and retinopathy, otherwise known as viral nervous necrosis, in marine fish worldwide. These viruses can be either horizontally or vertically transmitted and have been sporadically detected in invertebrates, which seem to be one of the possible viral sources. Twenty-eight new betanodavirus strains were retrieved in three molluscs species collected from different European countries between 2008 and 2015. The phylogenetic analyses revealed that strains retrieved from bivalve molluscs are closely related to viruses detected in finfish in Southern Europe in the period 2000-2009. Nevertheless, a new betanodavirus strain, markedly different from the other members of the RGNNV genotype, was detected. Such a massive and varied presence of betanodaviruses in bivalve molluscs greatly stresses the risks of transmission previously feared for other invertebrates. Bivalve molluscs reared in the same area as farmed and wild finfish could act as a reservoir of the virus. Furthermore, current European regulations allow relaying activities and the sale of live bivalve molluscs, which could pose a real risk of spreading betanodaviruses across different geographic regions. To our knowledge, this is the first study, which focuses on the detection and genetic characterization of betanodaviruses in bivalve molluscs. © 2017 John Wiley & Sons Ltd.

  14. Cardiovascular manifestations of phaeochromocytoma

    NARCIS (Netherlands)

    Prejbisz, A.; Lenders, J.W.M.; Eisenhofer, G.; Januszewicz, A.

    2011-01-01

    Clinical expression of phaeochromocytoma may involve numerous cardiovascular manifestations, but usually presents as sustained or paroxysmal hypertension associated with other signs and symptoms of catecholamine excess. Most of the life-threatening cardiovascular manifestations of phaeochromocytoma,

  15. A review of the feedbacks between bivalve grazing and ecosystem processes

    NARCIS (Netherlands)

    Prins, T.C.; Smaal, A.C.; Dame, R.F.

    1998-01-01

    This paper gives an overview of interactions between bivalve grazing and ecosystem processes, that may affect the carrying capacity of ecosystems for bivalve suspension feeders. These interactions consist of a number of positive and negative feedbacks. Bivalve grazing can result in local food

  16. Organisms associated with the sandy-beach bivalve Donax serra ...

    African Journals Online (AJOL)

    Examination of two collections of Donax serra from a South African west coast beach revealed the presence of Ciliophora, Trematoda, Nematoda and a parasitic pycnogonid. This is the first record of a pycnogonid from the genus Donax and the first published report of such a parasite from any southern African bivalve ...

  17. Lower Carboniferous marine bivalves from the Cantabrian Mountains (Spain)

    NARCIS (Netherlands)

    Amler, M.R.W.; Winkler Prins, C.F.

    1999-01-01

    The Lower Carboniferous bivalves of the Vegamián and Genicera formations are described, followed by a brief discussion on palaeoenvironmental and palaeogeographical aspects. The black shales of the Vegamián Fm. (Tournaisian) yield a peculiar association of euchondriid taxa (Euchondria wagneri sp.

  18. Skin manifestations of diabetes

    NARCIS (Netherlands)

    S. van Hattem (Simone); A.H. Bootsma (Aart); H.B. Thio (Bing)

    2008-01-01

    textabstractDiabetes mellitus can be complicated by a variety of cutaneous manifestations. Good metabolic control may prevent some of these manifestations and may support cure. Unfortunately, most glucose-lowering drugs also have cutaneous side effects. It is important to be able to recognize these

  19. e-Manifest

    Science.gov (United States)

    This is the primary hub for those seeking information about the e-Manifest system, its advisory board, and its development. Once the system is complete this area will serve as the portal into the e-Manifest system from EPA webpages.

  20. Light indirectly mediates bivalve habitat modification and impacts on seagrass

    DEFF Research Database (Denmark)

    Castorani, Max Christopher Nicholas; Glud, Ronnie N.; Hasler-Sheetal, Harald

    2015-01-01

    by directly or indirectly influencing the effects of habitat-modifying organisms that are capable of simultaneously ameliorating and exacerbating multiple stressors. Itwas hypothesized that light availability changes seagrassmetabolismand thereby indirectly regulates bivalve habitat modification...... and respiration),mussels and lowlight availability exacerbated sulfide intrusion of eelgrass tissues. Surprisingly, sulfide stress did not affect plant growth, survival, or energy stores. Thus, habitat modification by musselsmay represent a risk to eelgrass, especially during low productivity conditions...

  1. Ocean Acidification Has Multiple Modes of Action on Bivalve Larvae.

    Science.gov (United States)

    Waldbusser, George G; Hales, Burke; Langdon, Chris J; Haley, Brian A; Schrader, Paul; Brunner, Elizabeth L; Gray, Matthew W; Miller, Cale A; Gimenez, Iria; Hutchinson, Greg

    2015-01-01

    Ocean acidification (OA) is altering the chemistry of the world's oceans at rates unparalleled in the past roughly 1 million years. Understanding the impacts of this rapid change in baseline carbonate chemistry on marine organisms needs a precise, mechanistic understanding of physiological responses to carbonate chemistry. Recent experimental work has shown shell development and growth in some bivalve larvae, have direct sensitivities to calcium carbonate saturation state that is not modulated through organismal acid-base chemistry. To understand different modes of action of OA on bivalve larvae, we experimentally tested how pH, PCO2, and saturation state independently affect shell growth and development, respiration rate, and initiation of feeding in Mytilus californianus embryos and larvae. We found, as documented in other bivalve larvae, that shell development and growth were affected by aragonite saturation state, and not by pH or PCO2. Respiration rate was elevated under very low pH (~7.4) with no change between pH of ~ 8.3 to ~7.8. Initiation of feeding appeared to be most sensitive to PCO2, and possibly minor response to pH under elevated PCO2. Although different components of physiology responded to different carbonate system variables, the inability to normally develop a shell due to lower saturation state precludes pH or PCO2 effects later in the life history. However, saturation state effects during early shell development will carry-over to later stages, where pH or PCO2 effects can compound OA effects on bivalve larvae. Our findings suggest OA may be a multi-stressor unto itself. Shell development and growth of the native mussel, M. californianus, was indistinguishable from the Mediterranean mussel, Mytilus galloprovincialis, collected from the southern U.S. Pacific coast, an area not subjected to seasonal upwelling. The concordance in responses suggests a fundamental OA bottleneck during development of the first shell material affected only by

  2. Ocean Acidification Has Multiple Modes of Action on Bivalve Larvae.

    Directory of Open Access Journals (Sweden)

    George G Waldbusser

    Full Text Available Ocean acidification (OA is altering the chemistry of the world's oceans at rates unparalleled in the past roughly 1 million years. Understanding the impacts of this rapid change in baseline carbonate chemistry on marine organisms needs a precise, mechanistic understanding of physiological responses to carbonate chemistry. Recent experimental work has shown shell development and growth in some bivalve larvae, have direct sensitivities to calcium carbonate saturation state that is not modulated through organismal acid-base chemistry. To understand different modes of action of OA on bivalve larvae, we experimentally tested how pH, PCO2, and saturation state independently affect shell growth and development, respiration rate, and initiation of feeding in Mytilus californianus embryos and larvae. We found, as documented in other bivalve larvae, that shell development and growth were affected by aragonite saturation state, and not by pH or PCO2. Respiration rate was elevated under very low pH (~7.4 with no change between pH of ~ 8.3 to ~7.8. Initiation of feeding appeared to be most sensitive to PCO2, and possibly minor response to pH under elevated PCO2. Although different components of physiology responded to different carbonate system variables, the inability to normally develop a shell due to lower saturation state precludes pH or PCO2 effects later in the life history. However, saturation state effects during early shell development will carry-over to later stages, where pH or PCO2 effects can compound OA effects on bivalve larvae. Our findings suggest OA may be a multi-stressor unto itself. Shell development and growth of the native mussel, M. californianus, was indistinguishable from the Mediterranean mussel, Mytilus galloprovincialis, collected from the southern U.S. Pacific coast, an area not subjected to seasonal upwelling. The concordance in responses suggests a fundamental OA bottleneck during development of the first shell material

  3. Environmentally relevant microplastic exposure affects sediment-dwelling bivalves.

    Science.gov (United States)

    Bour, Agathe; Haarr, Ane; Keiter, Steffen; Hylland, Ketil

    2018-05-01

    Most microplastics are expected to sink and end up in marine sediments. However, very little is known concerning their potential impact on sediment-dwelling organisms. We studied the long-term impact of microplastic exposure on two sediment-dwelling bivalve species. Ennucula tenuis and Abra nitida were exposed to polyethylene microparticles at three concentrations (1; 10 and 25 mg/kg of sediment) for four weeks. Three size classes (4-6; 20-25 and 125-500 μm) were used to study the influence of size on microplastic ecotoxicity. Microplastic exposure did not affect survival, condition index or burrowing behaviour in either bivalve species. However, significant changes in energy reserves were observed. No changes were observed in protein, carbohydrate or lipid contents in E. tenuis, with the exception of a decrease in lipid content for one condition. However, total energy decreased in a dose-dependent manner for bivalves exposed to the largest particles. To the contrary, no significant changes in total energy were observed for A. nitida, although a significant decrease of protein content was observed for individuals exposed to the largest particles, at all concentrations. Concentration and particle size significantly influenced microplastic impacts on bivalves, the largest particles and higher concentrations leading to more severe effects. Several hypotheses are presented to explain the observed modulation of energy reserves, including the influence of microplastic size and concentration. Our results suggest that long-term exposure to microplastics at environmentally relevant concentrations can impact marine benthic biota. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Pulmonary manifestations of malaria

    Energy Technology Data Exchange (ETDEWEB)

    Rauber, K.; Enkerlin, H.L.; Riemann, H.; Schoeppe, W.

    1987-05-01

    We report on the two different types of pulmonary manifestations in acute plasmodium falciparum malaria. The more severe variant shows long standing interstitial pulmonary infiltrates, whereas in the more benign courses only short-term pulmonary edemas are visible.

  5. 5. Manifest / Margus Paju

    Index Scriptorium Estoniae

    Paju, Margus

    2007-01-01

    2.-9. veebr. on kinos "Sõprus" ja 11.-15. veebr. Tartu Sadamateatris 5. kultusfilmide festival Manifest, seekord USA filmid ja teemaks sõnavabadus. Esilinastub ka Urmas E. Liivi dokumentaalfilm "Tervitusi Nõukogude Eestist!"

  6. Ocular manifestations of candidemia

    NARCIS (Netherlands)

    Oude Lashof, A.M.L.; Rothova, A.; Sobel, J.D.; Ruhnke, M.; Pappas, P.G.; Viscoli, C.; Schlamm, H.T.; Oborska, I.T.; Rex, J.H.; Kullberg, B.J.

    2011-01-01

    BACKGROUND: Ocular candidiasis is a major complication of candidemia. The incidence, risk factors, and outcome of eye involvement during candidemia are largely unknown. We prospectively studied the ocular manifestations of candidemia in a large, worldwide, randomized multicenter trial that compared

  7. Extrahepatic manifestations of cholestasis

    NARCIS (Netherlands)

    Glasova, Helena; Beuers, Ulrich

    2002-01-01

    Pruritus, fatigue and metabolic bone disease represent three major extrahepatic manifestations of chronic cholestatic liver disease that considerably affect the patient's quality of life. The present article reviews pathogenetic aspects of and current therapeutic approaches to extrahepatic

  8. Predicting Effects of Coastal Acidification on Marine Bivalve ...

    Science.gov (United States)

    The partial pressure of carbon dioxide (pCO2) is increasing in the oceans and causing changes in seawater pH commonly described as ocean or coastal acidification. It is now well-established that, when reproduced in laboratory experiments, these increases in pCO2 can reduce survival and growth of early life stage bivalves. However, the effects that these impairments would have on whole populations of bivalves are unknown. In this study, these laboratory responses were incorporated into field-parameterized population models to assess population-level sensitivities to acidification for two northeast bivalve species with different life histories: Mercenaria mercenaria (hard clam) and Argopecten irradians (bay scallop). The resulting models permitted translation of laboratory pCO2 response functions into population-level responses to examine population sensitivity to future pCO2 changes. Preliminary results from our models indicate that if the current M. mercenaria negative population growth rate was attributed to the effects of pCO2 on early life stages, the population would decline at a rate of 50% per ten years at 420 microatmospheres (µatm) pCO2. If the current population growth rate was attributed to other additive factors (e.g., harvest, harmful algal blooms), M. mercenaria populations were predicted to decline at a rate of 50% per ten years at the preliminary estimate of 1010 µatm pCO2. The estimated population growth rate was positive for A. irradians,

  9. Inter- and intraspecific variation of carbon and nitrogen stable isotope ratios in freshwater bivalves

    OpenAIRE

    Novais, Adriana; Dias, Ester; Sousa, Ronaldo Gomes

    2016-01-01

    Freshwater bivalves provide important ecosystem functions and services, yet many of their ecological traits such as feeding mechanisms and resource use are largely ignored. In this study, we aimed to evaluate the potential overlap in resource use by bivalve species living in sympatry in European freshwater ecosystems. This was accomplished by analyzing the stable isotope ratios of carbon (C) and nitrogen (N) values of six bivalve species (five native species plus th...

  10. The Bivalve Production Chain in Santa Catarina, Brazil, and its Management and Operational Limitations

    OpenAIRE

    Gallon, Alessandra Vasconcelos; Universidade Federal do Ceará (UFC); Nascimento, Cristiano; Universidade Federal do Paraná - UFPR; Pfitscher, Elisete Dahmer; Universidade Federal de Santa Catarina

    2011-01-01

    Bivalve farming (mussels and oysters), a major component in the socio-economic development of the state of Santa Catarina, Brazil, combines the activities of public and private agencies in fish farming. Current analysis deals with the management and the operational limitations of the local bivalve production chain. Current exploratory research, undertaken by direct observations and the literature on the subject, employs data quality. Results show that the bivalve production chain, comprising ...

  11. Haematological manifestations of lupus

    Science.gov (United States)

    Fayyaz, Anum; Igoe, Ann; Kurien, Biji T; Danda, Debashish; James, Judith A; Stafford, Haraldine A; Scofield, R Hal

    2015-01-01

    Our purpose was to compile information on the haematological manifestations of systemic lupus erythematosus (SLE), namely leucopenia, lymphopenia, thrombocytopenia, autoimmune haemolytic anaemia (AIHA), thrombotic thrombocytopenic purpura (TTP) and myelofibrosis. During our search of the English-language MEDLINE sources, we did not place a date-of-publication constraint. Hence, we have reviewed previous as well as most recent studies with the subject heading SLE in combination with each manifestation. Neutropenia can lead to morbidity and mortality from increased susceptibility to infection. Severe neutropenia can be successfully treated with granulocyte colony-stimulating factor. While related to disease activity, there is no specific therapy for lymphopenia. Severe lymphopenia may require the use of prophylactic therapy to prevent select opportunistic infections. Isolated idiopathic thrombocytopenic purpura maybe the first manifestation of SLE by months or even years. Some manifestations of lupus occur more frequently in association with low platelet count in these patients, for example, neuropsychiatric manifestation, haemolytic anaemia, the antiphospholipid syndrome and renal disease. Thrombocytopenia can be regarded as an important prognostic indicator of survival in patients with SLE. Medical, surgical and biological treatment modalities are reviewed for this manifestation. First-line therapy remains glucocorticoids. Through our review, we conclude glucocorticoids do produce a response in majority of patients initially, but sustained response to therapy is unlikely. Glucocorticoids are used as first-line therapy in patients with SLE with AIHA, but there is no conclusive evidence to guide second-line therapy. Rituximab is promising in refractory and non-responding AIHA. TTP is not recognised as a criteria for classification of SLE, but there is a considerable overlap between the presenting features of TTP and SLE, and a few patients with SLE have concurrent

  12. Discrete-element modeling of nacre-like materials: Effects of random microstructures on strain localization and mechanical performance

    Science.gov (United States)

    Abid, Najmul; Mirkhalaf, Mohammad; Barthelat, Francois

    2018-03-01

    Natural materials such as nacre, collagen, and spider silk are composed of staggered stiff and strong inclusions in a softer matrix. This type of hybrid microstructure results in remarkable combinations of stiffness, strength, and toughness and it now inspires novel classes of high-performance composites. However, the analytical and numerical approaches used to predict and optimize the mechanics of staggered composites often neglect statistical variations and inhomogeneities, which may have significant impacts on modulus, strength, and toughness. Here we present an analysis of localization using small representative volume elements (RVEs) and large scale statistical volume elements (SVEs) based on the discrete element method (DEM). DEM is an efficient numerical method which enabled the evaluation of more than 10,000 microstructures in this study, each including about 5,000 inclusions. The models explore the combined effects of statistics, inclusion arrangement, and interface properties. We find that statistical variations have a negative effect on all properties, in particular on the ductility and energy absorption because randomness precipitates the localization of deformations. However, the results also show that the negative effects of random microstructures can be offset by interfaces with large strain at failure accompanied by strain hardening. More specifically, this quantitative study reveals an optimal range of interface properties where the interfaces are the most effective at delaying localization. These findings show how carefully designed interfaces in bioinspired staggered composites can offset the negative effects of microstructural randomness, which is inherent to most current fabrication methods.

  13. Atypical manifestations of leptospirosis.

    Science.gov (United States)

    Rajapakse, Senaka; Rodrigo, Chaturaka; Balaji, Krishan; Fernando, Sumadhya Deepika

    2015-05-01

    Leptospirosis is an illness with a wide spectrum of clinical manifestations and severe illness affects nearly all organ systems. Serious and potentially life-threatening clinical manifestations of acute leptospirosis are caused by both direct tissue invasion by spirochaetes and by the host immune responses. In its severe form, leptospirosis can cause multi-organ dysfunction and death in a matter of days. Therefore it is critical to suspect and recognize the disease early, in order to initiate timely treatment. While the classical presentation of the disease is easily recognized by experienced clinicians practising in endemic regions, rarer manifestations can be easily missed. In this systematic review, we summarize the atypical manifestations reported in literature in patients with confirmed leptospirosis. Awareness of these unusual manifestations would hopefully guide clinicians towards early diagnosis. © The Author 2015. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. Extrathoracic manifestations of tuberculosis

    International Nuclear Information System (INIS)

    Kienzl-Palma, D.; Prosch, H.

    2016-01-01

    Besides the lungs, tuberculosis (TB) can affect any organ system. In most cases, extrathoracic TB occurs in immunosuppressed patients as part of a severe illness via hematogenous spread. Extrathoracic involvement most commonly involves abdominal organs, especially the urogenital tract and less commonly the central nervous system (CNS) and the musculoskeletal system. Most frequently, computed tomography (CT) is used for detecting extrathoracic TB manifestations, except for CNS and musculoskeletal manifestations, where contrast-enhanced magnetic resonance imaging (MRI) is the gold standard. Extrathoracic manifestations of TB may be indistinguishable from inflammatory or malignant causes. Due to unspecific symptoms the diagnosis is often delayed. This article summarizes and discusses the various radiological manifestations of extrathoracic manifestation of TB. Radiological modalities for screening extrathoracic TB are CT and MRI. Conventional X-radiographs do not play a role in the diagnosis of extrathoracic TB. The possibility of extrathoracic TB should be considered particularly in immunosuppressed patients, such as the homeless, alcoholics or drug addicts or in patients with an immigrant background from the endemic areas of TB. The most likely site of extrathoracic TB is the abdomen; however, infections of the CNS or musculoskeletal systems and multisystem infections can also occur. In patients with suspected extrathoracic TB, radiological modalities for screening are CT, especially for abdominal infections and lymphadenopathy and MRI with contrast media for the musculoskeletal system and the CNS. (orig.) [de

  15. Sclerodermatomyositis, ocular manifestations.

    Science.gov (United States)

    Pedroza-Seres, M; Serna-Ojeda, J C; Flores-Suárez, L F

    2017-07-01

    Sclerodermatomyositis is an overlap syndrome of myositis and scleroderma, with dermatological, muscular and joint involvement, but may also present with ocular manifestations. A 57 year-old woman presented with ophthalmological manifestations, including scleral thinning 360°, and the presence of cells in the anterior and posterior chamber. Oriented physical examination and laboratory studies led to the diagnosis, with the need for systemic treatment. Sclerodermatomyositis is a rare disease. Its diagnosis needs thorough clinical and laboratory studies, and its management should be multidisciplinary when inflammatory ocular manifestations may be present. Copyright © 2016 Sociedad Española de Oftalmología. Publicado por Elsevier España, S.L.U. All rights reserved.

  16. Pulmonary manifestations of leptospirosis

    Directory of Open Access Journals (Sweden)

    Sameer Gulati

    2012-01-01

    Full Text Available Leptospirosis has a spectrum of presentation which ranges from mild disease to a severe form comprising of jaundice and renal failure. Involvement of the lung can vary from subtle clinical features to deadly pulmonary hemorrhage and acute respiratory distress syndrome. Of late, it has been identified that leptospirosis can present atypically with predominant pulmonary manifestations. This can delay diagnosis making and hence optimum treatment. The purpose of this review is to bring together all the reported pulmonary manifestations of leptospirosis and the recent trends in the management.

  17. Oral Manifestations of Menopause

    African Journals Online (AJOL)

    manifested in the oral cavity.[9] The teeth and gums are more affected by the hormonal changes occurring before menopause, which decrease the body's ability to fight minor infections or maintain a healthy balance of useful and harmful bacteria within the oral environment.[10] The dentist needs to be aware of oral ...

  18. Lower Oligocene bivalves of Ramanian Stage from Kachchh, Gujarat, India

    Science.gov (United States)

    Kachhara, R. P.; Jodhawat, R. L.; Devi, K. Bigyapati

    2012-04-01

    Marine Oligocene sequences in India outcrop only in western part of Kachchh. Earlier researchers have recognized the Oligocene strata under the Nari Series (Nagappa 1959; Chatterji and Mathur 1966). The Nari Series has a type area in Pakistan. It has two subdivisions - the Lower Nari (Lower Oligocene) and the Upper Nari (Upper Oligocene). It seems that there is no valid proof about the age of the Lower Nari due to lack of proper fauna (Eames 1975), and according to Pascoe (1962), the Upper Nari slightly transgress into Aquitanian (Lower Miocene), therefore, one has to be very cautious. Biswas and Raju (1971) reclassified the Oligocene strata of Kachchh and lithostratigraphically clubbed them as the Maniyara Fort Formation with type section along the Bermoti stream. This Formation has four members. The lower three members correspond to the Ramanian Stage (Lower Oligocene, Biswas 1971, 1973) while the uppermost to the Waiorian Stage (Upper Oligocene, Biswas 1965, 1971, 1973). The Ramanian Stage is characterized by large forams especially Nummulites fichteli, Nummulites fichteli intermedius, Lepidocyclina ( Eulepidina) dialata and Operculina sp. Several ostracods are also known to occur. Megafauna include bivalves, gastropods, echinoids, corals, mammals and reptiles. Concerning bivalves earlier researchers have recorded a few taxa namely Trisidos semitorta (Lamarck), Cubitostrea angulata (J de C Sowerby), Pecten ( Amussiopecten) labadyei d'Archiac and Haime, Periglypta puerpera (Linne') var. aglaurae Brongniart, Ostrea fraasi Mayer Eymer and listed Pecten laevicostatus J de C Sowerby, Callista pseudoumbonella Vredenburg and Clementia papyracea (Gray) from Kachchh as against overall 42 forms from the Nari Series as a whole (Vredenburg 1928). This tempted us to make an attempt to collect bivalve fauna systematically which are occurring prolifically in the Ramanian Stage. In the present work, for this purpose, sections are worked out around Lakhpat (23°50'N; 68°47'E

  19. qPCR analysis of bivalve larvae feeding preferences when grazing on mixed microalgal diets.

    Directory of Open Access Journals (Sweden)

    Kai Liao

    Full Text Available Characterization of the feeding preferences of bivalve larvae would help improving the bivalve aquaculture and hatchery by providing appropriate microalgal diets. However, inaccurate and laborious identification and counting of microalgal species have challenged the selective feeding of bivalves. In the present study, we developed a highly specific and sensitive assay using quantitative polymerase chain reaction (qPCR to assess the selective feeding of bivalve larvae based on species-specific primers targeting to microalgal 18S rDNA sequences. The assay exhibited good specificity. The detection limits of the qPCR assay were 769, 71, 781 and 21 18S rDNA copies for Chaetoceros calcitrans, Isochrysis galbana, Platymonas helgolandica and Nannochloropsis oculata, respectively. Using such assay, we found that C. calcitrans and I. galbana were preferentially ingested, whereas N. oculata was preferentially rejected in biodeposits of four bivalve species, Tegillarca gransa, Cyclina sinensis, Scapharca subcrenata and Sinonovacula constricta. Furthermore, our growth experiments revealed that C. calcitrans and I. galbana could significantly promote the shell growth, whereas feeding of N. oculata resulted in poorer growth of four bivalve species. These data indicated that qPCR might be useful in screening of efficient and reliable microalgal species for each bivalve species, leading to improved bivalve aquaculture and hatchery.

  20. MAPPING THE DISTRIBUTION OF HARVESTED ESTUARINE BIVALVES WITH NATURAL HISTORY-BASED HABITAT SUITABILITY MODELS

    Science.gov (United States)

    Maps of harvested bivalve populations are invaluable for the management of fisheries species, yet the cost to produce them typically limits their availability. Here, we demonstrate a relatively low-cost approach to generate habitat maps for five species of bivalves found in many ...

  1. Effect of dietary polyunsaturated fatty acids on reproductive output and larval growth of bivalves

    NARCIS (Netherlands)

    Hendriks, I.E.; Van Duren, L.A.; Herman, P.M.J.

    2003-01-01

    The pre-spawning condition of adult bivalves is influenced by quantity and quality of available food. For bivalves, the essential polyunsaturated fatty acids (PUFAs) eicosapentaenoic acid (EPA) 20:5(n-3) and docosahexaenoic acid (DHA) 22:6(n-3) are presumed to determine the nutritional value of

  2. Thyasirid bivalves from Cretaceous and Paleogene cold seeps

    Directory of Open Access Journals (Sweden)

    Krzysztof Hryniewicz

    2017-11-01

    Full Text Available We present a systematic study of thyasirid bivalves from Cretaceous to Oligocene seep carbonates worldwide. Eleven species of thyasirid bivalves are identified belonging to three genera: Conchocele, Maorithyas, and Thyasira. Two species are new: Maorithyas humptulipsensis sp. nov. from middle Eocene seep carbonates in the Humptulips Formation, Washington State, USA, and Conchocele kiritachiensis sp. nov. from the late Eocene seep deposit at Kiritachi, Hokkaido, Japan. Two new combinations are provided: Conchocele townsendi (White, 1890 from Maastrichtian strata of the James Ross Basin, Antarctica, and Maorithyas folgeri (Wagner and Schilling, 1923 from Oligocene rocks from California, USA. Three species are left in open nomenclature. We show that thyasirids have Mesozoic origins and appear at seeps before appearing in “normal” marine environments. These data are interpreted as a record of seep origination of thyasirids, and their subsequent dispersal to non-seep environments. We discuss the age of origination of thyasirids in the context of the origin of the modern deep sea fauna and conclude that thyasirids could have deep sea origins. This hypothesis is supported by the observed lack of influence of the Cretaceous and Paleogene Oceanic Anoxic Events on the main evolutionary lineages of the thyasirids, as seen in several other members of the deep sea fauna.

  3. The miRNA biogenesis in marine bivalves

    Directory of Open Access Journals (Sweden)

    Umberto Rosani

    2016-03-01

    Full Text Available Small non-coding RNAs include powerful regulators of gene expression, transposon mobility and virus activity. Among the various categories, mature microRNAs (miRNAs guide the translational repression and decay of several targeted mRNAs. The biogenesis of miRNAs depends on few gene products, essentially conserved from basal to higher metazoans, whose protein domains allow specific interactions with dsRNA. Here, we report the identification of key genes responsible of the miRNA biogenesis in 32 bivalves, with particular attention to the aquaculture species Mytilus galloprovincialis and Crassostrea gigas. In detail, we have identified and phylogenetically compared eight evolutionary conserved proteins: DROSHA, DGCR8, EXP5, RAN, DICER TARBP2, AGO and PIWI. In mussels, we recognized several other proteins participating in the miRNA biogenesis or in the subsequent RNA silencing. According to digital expression analysis, these genes display low and not inducible expression levels in adult mussels and oysters whereas they are considerably expressed during development. As miRNAs play an important role also in the antiviral responses, knowledge on their production and regulative effects can shed light on essential molecular processes and provide new hints for disease prevention in bivalves.

  4. Manifest of depth sociopsychology

    OpenAIRE

    ZELITCHENKO ALEXANDER

    2013-01-01

    The observations of motives of activity of big groups (nations, confessions etc.) as a whole result in discovery of the part of unconscious mind that is common for all members of big group a collective unconscious. Two parts of collective unconscious may be determined: the collective superconscious known first as a group archetype and the collective subconscious, which manifest itself for example in phenomenon of collective trauma. Depth sociopsychology is a science about the collective uncon...

  5. Thoracic manifestation of tuberculosis

    International Nuclear Information System (INIS)

    Kienzl-Palma, D.; Prosch, H.

    2016-01-01

    Tuberculosis (TB) is a granulomatous disease caused by Mycobacterium tuberculosis and transmission is via an airborne route by droplet infection. In the majority of cases patients have thoracic TB, which most frequently presents with hilar lymphadenopathy and pulmonary manifestation. Due to the rise in incidence of TB in central Europe to be expected over the coming years, it is essential to be acquainted with the radiological manifestations of pulmonary TB, particularly to be able to discriminate active from inactive TB. Due to the use of molecular techniques entailing DNA fingerprinting, the traditional classification of TB in primary and postprimary TB is being challenged. These genetic studies have revealed that variations in the clinical and radiographic appearance of TB are mainly affected by the immune status of the patients. Due to the low prevalence of TB in central Europe and the wide variation of radiological presentations, the diagnosis and therapy of TB is often delayed. In this article, the radiographic manifestations of thoracic TB are summarized and discussed. Together with the medical history and bacteriological tests, chest X-ray imaging and computed tomography (CT) play a major role not only in the detection of TB but also in the follow-up during and after therapy. Chest X-radiographs should be the primary diagnostic method in patients with suspected TB in screening as well as for diagnosis and therapy monitoring. The use of CT is more sensitive than chest radiographs and is frequently performed after chest radiographs to obtain detailed information about subtle parenchymal changes or lymph node manifestation. When active TB is suspected CT should be performed. Tree in bud, lobular consolidations, centrilobular nodules, cavities and ground-glass opacification are typical changes in active TB. (orig.) [de

  6. Manifestations of Lyme carditis.

    Science.gov (United States)

    Kostić, Tomislav; Momčilović, Stefan; Perišić, Zoran D; Apostolović, Svetlana R; Cvetković, Jovana; Jovanović, Andriana; Barać, Aleksandra; Šalinger-Martinović, Sonja; Tasić-Otašević, Suzana

    2017-04-01

    The first data of Lyme carditis, a relatively rare manifestation of Lyme disease, were published in eighties of the last century. Clinical manifestations include syncope, light-headedness, fainting, shortness of breath, palpitations, and/or chest pain. Atrioventricular (AV) electrical block of varying severity presents the most common conduction disorder in Lyme carditis. Although is usually mild, AV block can fluctuates rapidly and progress from a prolonged P-R interval to a His-Purkinje block within minutes to hours and days. Rarely, Lyme disease may be the cause of endocarditis, while some studies and reports, based on serological and/or molecular investigations, have suggested possible influence of Borrelia burgdorferi on degenerative cardiac valvular disease. Myocarditis, pericarditis, pancarditis, dilated cardiomyopathy, and heart failure have also been described as possible manifestations of Lyme carditis. The clinical course of Lyme carditis is generally mild, short term, and in most cases, completely reversible after adequate antibiotic treatment. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  7. Discourse Manifestation of Personality

    Directory of Open Access Journals (Sweden)

    Владимир Ильич Карасик

    2016-12-01

    Full Text Available The paper deals with approaches to discourse studies. The approaches may be regarded as discourse dimensions associated with models presented and substantiated by M.M. Bakhtin, J. Habermas, Yu.M. Lotman and M.A.K. Halliday. They comprise contents, participants, tonality, channel and communicative actions. The approaches described complement each other and make it possible to synthesize the results achieved in Text Linguistics, Pragmatics, Social Linguistics, and Discourse Studies. They are joined by and oriented towards the concept of Language Personality, i.e. persons who manifest themselves in various kinds of communicative situations. However, each discourse dimension corresponds to a certain type of discourse. A Topic Approach to discourse focuses upon its contents (its referential substance and specifies the correlation between explicit and implicit meaning expression. A Subject Approach to discourse makes it possible to single out and describe two basic types of communication as presented in Personality bound and Status bound discourse, the former diverges into two subtypes - Habitual and Existential communication, whereas the latter is manifested in various kinds of Institutional discourse. A Tonality Approach to discourse highlights different types of stylistic and emotional modes of communication and correspondingly characterizes personality types who are engaged in such situations. A Regime Approach is concentrated on communication channel and technical peculiarities of behavior determined by those restrictions. An Action Approach to discourse gives us a broader understanding of a performative act, i.e. an action incorporated in culture and a situational behavioral interaction.

  8. Light indirectly mediates bivalve habitat modification and impacts on seagrass

    DEFF Research Database (Denmark)

    Castorani, Max Christopher Nicholas; Glud, Ronnie N.; Hasler-Sheetal, Harald

    2015-01-01

    and respiration),mussels and lowlight availability exacerbated sulfide intrusion of eelgrass tissues. Surprisingly, sulfide stress did not affect plant growth, survival, or energy stores. Thus, habitat modification by musselsmay represent a risk to eelgrass, especially during low productivity conditions...... by directly or indirectly influencing the effects of habitat-modifying organisms that are capable of simultaneously ameliorating and exacerbating multiple stressors. Itwas hypothesized that light availability changes seagrassmetabolismand thereby indirectly regulates bivalve habitat modification...... and subsequent impacts on seagrasses by shifting net effects between alleviation of nutrient stress and intensification of sulfide stress. To test this hypothesis, manipulations of light availability and blue mussel (Mytilus edulis) abundance were made in eelgrass (Zostera marina) mesocosms and biogeochemical...

  9. Optimal designs of mollusk shells from bivalves to snails.

    Science.gov (United States)

    Okabe, Takuya; Yoshimura, Jin

    2017-02-10

    Bivalve, ammonite and snail shells are described by a small number of geometrical parameters. Raup noted that the vast majority of theoretically possible shell forms do not occur in nature. The constraint factors that regulate the biased distribution of natural form have long since been an open problem in evolution. The problem of whether natural shell form is a result of optimization remains unsolved despite previous attempts. Here we solve this problem by considering the scaling exponent of shell thickness as a morphological parameter. The scaling exponent has a drastic effect on the optimal design of shell shapes. The observed characteristic shapes of natural shells are explained in a unified manner as a result of optimal utilization of shell material resources, while isometric growth in thickness leads to impossibly tight coiling.

  10. Protozoan parasites of bivalve molluscs: literature follows culture.

    Directory of Open Access Journals (Sweden)

    José A Fernández Robledo

    Full Text Available Bivalve molluscs are key components of the estuarine environments as contributors to the trophic chain, and as filter -feeders, for maintaining ecosystem integrity. Further, clams, oysters, and scallops are commercially exploited around the world both as traditional local shellfisheries, and as intensive or semi-intensive farming systems. During the past decades, populations of those species deemed of environmental or commercial interest have been subject to close monitoring given the realization that these can suffer significant decline, sometimes irreversible, due to overharvesting, environmental pollution, or disease. Protozoans of the genera Perkinsus, Haplosporidium, Marteilia, and Bonamia are currently recognized as major threats for natural and farmed bivalve populations. Since their identification, however, the variable publication rates of research studies addressing these parasitic diseases do not always appear to reflect their highly significant environmental and economic impact. Here we analyzed the peer- reviewed literature since the initial description of these parasites with the goal of identifying potential milestone discoveries or achievements that may have driven the intensity of the research in subsequent years, and significantly increased publication rates. Our analysis revealed that after initial description of the parasite as the etiological agent of a given disease, there is a time lag before a maximal number of yearly publications are reached. This has already taken place for most of them and has been followed by a decrease in publication rates over the last decade (20- to 30- year lifetime in the literature. Autocorrelation analyses, however, suggested that advances in parasite purification and culture methodologies positively drive publication rates, most likely because they usually lead to novel molecular tools and resources, promoting mechanistic studies. Understanding these trends should help researchers in

  11. Reproductive investment in the intertidal bivalve Macoma balthica

    Science.gov (United States)

    Honkoop, P. J. C.; Van der Meer, J.; Beukema, J. J.; Kwast, D.

    1999-05-01

    Bivalve eggs generally contain large amounts of lipids which, in comparison with proteins and carbohydrates, have high energy contents and are thus costly in energetic terms. As lipid contents vary between species, comparisons of reproductive investments should not only include numbers and sizes of eggs, but also their energy content. We estimated the investment in egg material of mature females of the Baltic tellin Macoma balthica (L.) in terms of both mass and energy content. All mass below a minimum body mass (below which no eggs are produced) was defined as structural mass. This threshold amounts to a body mass index (BMI) of 5.6 (ash-free dry mass per cubic shell length in mg cm -3). More than half (55%) of the mass above the structural mass was invested in egg material and 45% in extra somatic tissue and tissue for production and storage of gametes. This means that the amount of eggs spawned ranged from 0 (at BMI = 5.6 mg cm -3) to 33% of the total ash-free dry mass (at a high BMI value of 14 mg cm -3). Eggs contained a relatively large amount of lipids, about 30% of their ash-free dry mass, whereas non-egg material contained only about 7% lipids. Eggs of two other bivalves in the Wadden Sea, the cockle Cerastoderma edule and the mussel Mytilus edulis, were smaller and contained only about 11% and 20% lipids, respectively. Energy content of M. balthica eggs amounted to ˜0.006 J, in the other two species to ˜0.002 J. The function of the more expensive eggs in M. balthica may be related to its early spawning in spring, causing slower larval development until first feeding.

  12. [Buccal manifestations of AIDS].

    Science.gov (United States)

    Burlibaşa, C; Tovaru, S

    1989-01-01

    The disease determined by HIV, increasingly more frequent, is affecting certain groups of patients (homosexuals, drug addicts, polytransfused subjects). The clinical picture at the onset is not specific. Later on in the course of the disease the immunological capacity of defense of the organism is affected and a series of symptoms including fever, infections with bacteria, lymph-node inflammation, encephalopathies, Kaposi sarcoma will develop. Apparently buccal infections with fungi are the earliest manifestations, and they are followed, by order of frequency, by herpetic lesions, "hairy" leucoplasia, tumours. Transmission through the saliva from the patient to the stomatologist of the HIV infection is theoretically possible due to scratches on the physicians' hands. Prophylactic measures are described for the stomatologists treating AIDS patients, as well as for the sterilization of the instruments.

  13. [Pulmonary Manifestations of Vasculitis].

    Science.gov (United States)

    von Vietinghoff, S

    2016-11-01

    The variable symptoms and signs of pulmonary vasculitis are a diagnostic and therapeutic challenge. Vasculitis should be considered in rapidly progressing, severe and unusual manifestations of pulmonary disease. Clinical examination of other organ systems typically affected by vasculitis such as skin and kidney and autoantibody measurements are complementary approaches to manage this situation. Pulmonary involvement is common in small vessel vasculitis including anti-GBM disease (Goodpasture syndrome) and the ANCA-associated vasculitides. Life threatening pulmonary hemorrhage and irreversible damage of other organs, frequently the kidney, are important complications necessitating rapid diagnosis of these conditions.Vasculitides are rare diseases of multiple organs and therapies including biologics are evolving rapidly, requiring cooperation of specialities and with specialized centres to achieve best patient care. All involved physicians should be aware of typical complications of immunosuppressive therapy. © Georg Thieme Verlag KG Stuttgart · New York.

  14. Respiratory manifestations of hypothyroidism

    DEFF Research Database (Denmark)

    Sorensen, Jesper Roed; Winther, Kristian Hillert; Bonnema, Steen Joop

    2016-01-01

    BACKGROUND: Hypothyroidism has been associated with increased pulmonary morbidity and overall mortality. We conducted a systematic review to identify the prevalence and underlying mechanisms of respiratory problems among patients with thyroid insufficiency. METHODS: PubMed and EMBASE databases were...... searched for relevant literature from January 1950 through January 2015 with study eligibility criteria: English-language publications; Adult subclinical or overt hypothyroid patients; Intervention, observational or retrospective studies; and respiratory manifestations. We followed the PRISMA statement......% of newly diagnosed patients with overt hypothyroidism, and demonstrated reversibility following treatment. The evidence for or against a direct effect on pulmonary function was ambiguous. However, each of the above mentioned areas were only dealt with in a limited number of studies. Therefore, we refrain...

  15. Escape Burrowing of Modern Freshwater Bivalves as a Paradigm for Escape Behavior in the Devonian Bivalve Archanodon catskillensis

    Directory of Open Access Journals (Sweden)

    Katja Knoll

    2017-10-01

    Full Text Available Many freshwater bivalves restore themselves to the sediment water interface after burial by upward escape burrowing. We studied the escape burrowing capacity of two modern unionoids, Elliptio complanata and Pyganodon cataracta and the invasive freshwater venerid Corbicula fluminea, in a controlled laboratory setting varying sediment grain size and burial depth. We found that the relatively streamlined E. complanata is a better escape burrower than the more obese P. cataracta. E. complanata is more likely to escape burial in both fine and coarse sand, and at faster rates than P. cataracta. However, successful escape from 10 cm burial, especially in fine sand, is unlikely for both unionoids. The comparatively small and obese C. fluminea outperforms both unionoids in terms of escape probability and escape time, especially when body size is taken into consideration. C. fluminea can escape burial depths many times its own size, while the two unionoids rarely escape from burial equivalent to the length of their shells. E. complanata, and particularly P. cataracta, are morphological paradigms for the extinct Devonian unionoid bivalve Archanodon catskillensis, common in riverine facies of the Devonian Catskill Delta Complex of the eastern United States. Our observations suggest that the escape burrowing capability of A. catskillensis was no better than that of P. cataracta. Archanodon catskillensis was likely unable to escape burial of more than a few centimeters of anastrophically deposited sediment. The long (up to 1 meter, vertical burrows that are associated with A. catskillensis, and interpreted to be its escape burrows, represent a response to episodic, small-scale sedimentation events due to patterns of repetitive hydrologic or weather-related phenomena. They are not a response to a single anastrophic event involving the influx of massive volumes of sediment.

  16. Bivalve aquaculture transfers in Atlantic Europe. Part A: Transfer activities and legal framework

    DEFF Research Database (Denmark)

    Muehlbauer, F.; Fraser, D.; Brenner, M.

    2014-01-01

    environment and address economic considerations remains unanswered. This study provides the first overview of bivalve transfer activities for aquaculture purposes along the European Atlantic coast. Existing international and EU legislation is described, and potential weaknesses in the existing legislative...

  17. Mercury accumulation in marine bivalves: Influences of biodynamics and feeding niche

    Energy Technology Data Exchange (ETDEWEB)

    Pan Ke [Division of Life Science, Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon (Hong Kong); Wang Wenxiong, E-mail: wwang@ust.hk [Division of Life Science, Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon (Hong Kong)

    2011-10-15

    Differences in the accumulation of mercury (Hg) in five species of marine bivalves, including scallops Chlamys nobilis, clams Ruditapes philippinarum, oysters Saccostrea cucullata, green mussels Perna viridis, and black mussels Septifer virgatus, were investigated. The bivalves displayed different patterns of Hg accumulation in terms of the body concentrations of methylmercury (MeHg) and total Hg (THg), as well as the ratio of MeHg to THg. Parameters of the biodynamics of the accumulation of Hg(II) and MeHg could reflect the species-dependent Hg concentrations in the bivalves. With the exception of black mussels, we found a significant relationship between the efflux rates of Hg(II) and the THg concentrations in the bivalves. The interspecific variations in the MeHg to THg ratio were largely controlled by the relative difference between the elimination rates of Hg(II) and MeHg. Stable isotope ({delta}{sup 13}C) analysis indicated that the five bivalve species had contrasting feeding niches, which may also affect the Hg accumulation. - Highlights: > Significant difference in Hg accumulation and MeHg:THg ratio in different bivalves. > THg concentrations in the bivalves were generally related to the efflux rates of Hg(II). > Elimination of Hg(II) and MeHg controlled the interspecific variation in MeHg:THg ratio. > MeHg and THg concentrations reflect the interaction of Hg biodynamics and food. - The species-specific body concentrations of MeHg and THg in bivalves reflect the complicated interaction between the biodynamics of Hg(II) and MeHg and the different food sources.

  18. Mesozoic-Cenozoic crustaceans preserved within echinoid tests and bivalve shells

    OpenAIRE

    Gašparič, Rok; Fraaije, René H. B.; van Bakel, Barry W. M.; Jagt, John W. M.; Skupien, Petr

    2015-01-01

    Associations of crustaceans with echinoids (Echinodermata) and bivalves (Mollusca) are not uncommon in modern oceans. Here we record the occurrence of anomurans, brachyurans and isopods within echinoid tests and bivalve shells from the Middle Jurassic of France, the Upper Jurassic of the Czech Republic, the Eocene of Croatia and the Miocene of Austria. Additionally a new genus and species of fossil cirolanid isopod from the Middle Jurassic of France is described. The present examp...

  19. Strontium and barium incorporation into freshwater bivalve shells

    Science.gov (United States)

    Zhao, Liqiang; Schöne, Bernd R.

    2015-04-01

    Despite strong vital control, trace elements of bivalve shells can potentially serve as proxies of environmental change. However, to reconstruct past environments with the geochemical properties of the shells and determine the degree to which the element levels are biologically influenced, it is essential to experimentally determine the relationship between environmental variables and the element composition of the shells. In particular, the trace element geochemistry of freshwater bivalve shells has so far received little attention. Here, we present a controlled laboratory experiment that aimed at providing a better understanding of the influence of changing environmental variables on the incorporation of trace elements into freshwater bivalve shells. Under controlled conditions, Asian clams Corbicula fluminea were reared for 5 weeks in three sets of experiments: (1) different water temperature (10, 16, and 22° C) and different food levels (an equally mixed Scenedesmu quadricanda and Chlorella vulgaris at rations of 0.4, 2, 4, and 8 × 104 cells ml-1 d-1); (2) different water temperature (10, 16, and 22° C) and different element levels (Sr, Ba); (3) five sediment types (sand, slightly muddy sand, muddy sand, slightly sandy mud and mud). In the first set of experiments, shell Sr/Ca showed a significantly negative correlation with temperature, where Sr/Ca decreased linearly by about 1.6 to 2.1% per 1° C, but responded far more weakly to food availability. On the other hand, temperature and food availability affected shell Ba/Ca ratios, which potentially confounds the interpretation of Ba/Ca variations. Moreover, shell Sr/Ca and Ba/Ca exhibited a clearly negative dependence on shells growth rate that varied significantly among combinations of temperature and food availability. In the second set of experiments, shell Sr/Ca and Ba/Ca were positively and linearly related to water Sr/Ca and Ba/Ca for all temperatures. However, significantly negative effects of

  20. Pulmonary manifestation of leptospirosis

    Energy Technology Data Exchange (ETDEWEB)

    Im, Jung Gi; Yeon, Kyung Mo; Han, Man Chung; Kim, Chu Wan; Lee, Jung Sang; Kim, Suhng Gwon; Han, Yong Chol; Chang, Woo Hyun; Chi, Je Geun [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1986-02-15

    Authors analysed and present chest X-ray findings of serologically proven leptospirosis from Seoul National University Hospital, either admitted or referred for serological verification, during recent 2 years. Radiological findings were correlated with the lung specimen findings of experimentally induced leptospirosis in guinea pig. The results are as follows: 1. 24 cases (56%) showed positive X-ray findings. 2. Predominant radiological patterns of involved lung were tiny dot, small nodule, rosette density in 11 cases, massive confluent consolidation in 4 cases, and diffuse ill-defined velly increased density in 9 cases. 3. Distribution of pulmonary lesions were bilateral (100%), non-lobar, non-segmental (95%), and there were conspicuous tendency of peripheral lung predominance. 4. Extrapulmonary manifestation, such as pleural effusion or cardiomegaly was rate. 5. Pulmonary lesions resolved completely usually 5 to 10 days after their appearance. 6. From the gross and microscopic findings of serially sacrificed guinea pig's lung and a case of autopsy, authors concluded that fine dot-like density in chest X-ray was due to paleolithic hemorrhage in intraalveolar space at initial stage, growing up to ressette density or confluent consolidation as the pathetic extends to surrounding lung forming purpura and coalescent hemorrhage.

  1. Short-term fluctuations in bivalve larvae compared with some environmental factors in a coastal lagoon (South Portugal

    Directory of Open Access Journals (Sweden)

    Luis M.Z. Chícaro

    2000-12-01

    Full Text Available In this study, short-term fluctuations in bivalve larvae were compared with some triggering factors for a period of sixteen months. Data on the abundance of planktonic larvae, collected two to three times a week were related to water temperature, salinity, wind velocity, tidal amplitude and chlorophyll a. Higher densities of planktonic bivalve larvae were caught between May and August, but intense fluctuations in abundance were observed. Planktonic bivalve larvae of eighteen taxa were identified. Larvae of Mytilus galloprovincialis, Cerastoderma edule, Ruditapes decussates and Venerupis spp. were the most abundant. The seasonal fluctuations of bivalve abundance seem to be controlled by temperature, the major factor in the timing of the reproduction of bivalves. Nevertheless, advection may be also a key factor during the planktonic life of bivalve species in coastal systems, such as the Ria Formosa.

  2. Anoxic survival potential of bivalves: (arte)facts.

    Science.gov (United States)

    de Zwaan, Albertus; Babarro, Jose M F; Monari, Marta; Cattani, Otello

    2002-03-01

    The anoxic survival time of the bivalves Chamelea gallina, Cerastoderma edule and Scapharca inaequivalvis from two different ecosystems and differing anoxia tolerances was studied in static (closed) and flow-through systems. The antibiotics chloramphenicol, penicillin and polymyxin were added, and molybdate (specific inhibitor of the process of sulfate reduction). Survival in (near) anoxic seawater of Chamelea was studied in a static system by comparing untreated seawater with autoclaved seawater and untreated clams with clams incubated in well-aerated seawater, containing the broad-spectrum antibiotic chloramphenicol, prior to the anoxic survival test. With untreated clams and natural seawater (median mortality time 2.4 days) a decrease in pH and exponential accumulation of sulfide and ammonium was observed in the anoxic medium, indicating excessive growth of (sulfate reducing) bacteria. In sterilized seawater LT50 (2.1 days) was not significantly different and again considerable amounts of ammonium and sulfide accumulated. However, pre-treatment of clams with chloramphenicol resulted in an increase of LT50 (11.0 days) by approximately fivefold. Accumulation of ammonium and sulfide was retarded, but was finally even stronger than in the medium containing untreated clams. Median mortality times were 2.5 and 2.4 days for Chamelea and 2.7 and 2.9 days for Cerastoderma for static and flow-through incubations, respectively. Addition of chloramphenicol increased strongly survival time in both systems with corresponding values of 11.0 and 16.3 days for Chamelea, and 6.4 and 6.5 days for Cerastoderma. LT50 of Scapharca in anoxic seawater was 14.4 days. Chloramphenicol and penicillin increased median survival time to 28.5 and 28.7 days, respectively, whereas polymyxin displayed no effect (LT50=13.6 days). Molybdate added to artificial sulfate free seawater blocked biotic sulfide formation, but did not improve survival time (LT50=13.7 days). Overall the results indicate

  3. An aquaculture-based method for calibrated bivalve isotope paleothermometry

    Science.gov (United States)

    Wanamaker, Alan D.; Kreutz, Karl J.; Borns, Harold W.; Introne, Douglas S.; Feindel, Scott; Barber, Bruce J.

    2006-09-01

    To quantify species-specific relationships between bivalve carbonate isotope geochemistry (δ18Oc) and water conditions (temperature and salinity, related to water isotopic composition [δ18Ow]), an aquaculture-based methodology was developed and applied to Mytilus edulis (blue mussel). The four-by-three factorial design consisted of four circulating temperature baths (7, 11, 15, and 19°C) and three salinity ranges (23, 28, and 32 parts per thousand (ppt); monitored for δ18Ow weekly). In mid-July of 2003, 4800 juvenile mussels were collected in Salt Bay, Damariscotta, Maine, and were placed in each configuration. The size distribution of harvested mussels, based on 105 specimens, ranged from 10.9 mm to 29.5 mm with a mean size of 19.8 mm. The mussels were grown in controlled conditions for up to 8.5 months, and a paleotemperature relationship based on juvenile M. edulis from Maine was developed from animals harvested at months 4, 5, and 8.5. This relationship [T°C = 16.19 (±0.14) - 4.69 (±0.21) {δ18Oc VPBD - δ18Ow VSMOW} + 0.17 (±0.13) {δ18Oc VPBD - δ18Ow VSMOW}2; r2 = 0.99; N = 105; P < 0.0001] is nearly identical to the Kim and O'Neil (1997) abiogenic calcite equation over the entire temperature range (7-19°C), and it closely resembles the commonly used paleotemperature equations of Epstein et al. (1953) and Horibe and Oba (1972). Further, the comparison of the M. edulis paleotemperature equation with the Kim and O'Neil (1997) equilibrium-based equation indicates that M. edulis specimens used in this study precipitated their shell in isotopic equilibrium with ambient water within the experimental uncertainties of both studies. The aquaculture-based methodology described here allows similar species-specific isotope paleothermometer calibrations to be performed with other bivalve species and thus provides improved quantitative paleoenvironmental reconstructions.

  4. CT manifestation of hepatic toxoplasmosis

    International Nuclear Information System (INIS)

    Mao Qing; Yang Yaying; Bao Yanming; He Bo; Wang Kechao; Song Guangyi; Lu Lin; Wang Xiaoli

    2005-01-01

    Objective: To study the CT manifestation of hepatic toxoplasmosis, and to provide image basis for its clinical diagnosis. Methods: Three patients with hepatic toxoplasmosis were examined by abdomen MSCT (pre- and post-contrast), and were confirmed by laboratory exams. The images were analyzed with information of clinical manifestation. Results: The positive appearances included the enlargement of liver, patches of multiple scattered low densities. Post-contrast lesions appearances: (1) No significant enhancement. (2) No significant occupying effection, and normal vessels inserting lesion occasionally. Conclusion: CT manifestation of hepar toxoplasmosis are some characteristic. But the diagnosis was made by a combination both clinical manifestation and laboratory exams. (authors)

  5. A Darriwilian (Middle Ordovician) bivalve-dominated molluscan fauna from the Stairway Sandstone, Amadeus Basin, central Australia

    OpenAIRE

    Kristian G. Jakobsen; Glenn A. Brock; Arne T. Nielsen

    2016-01-01

    A bivalve-dominated molluscan fauna is described from the Darriwilian (Middle Ordovician) Stairway Sandstone, Amadeus Basin, central Australia. The fauna comprises 16 species of bivalves and rostroconchs plus six gastropod species which are treated under open nomenclature. Two new bivalves, Sthenodonta paenesymmetrica sp. nov. and Modiolopsis pojetai sp. nov., are described. The relatively low-diverse molluscan fauna constitutes around 62% of the total benthic macrofauna. Approximately 75% of...

  6. Bacteriophages as enteric viral indicators in bivalve mollusc management.

    Science.gov (United States)

    Hodgson, Kate R; Torok, Valeria A; Turnbull, Alison R

    2017-08-01

    Human enteric viruses, such as norovirus and hepatitis A virus, are spread by a variety of routes including faecal-oral transmission. Contaminated bivalve shellfish are regularly implicated in foodborne viral disease outbreaks internationally. Traditionally indicator bacteria, the coliforms and Escherichia coli, have been used to detect faecal pollution in growing waters and shellfish. However, studies have established that they are inadequate as indicators of the risk of human enteric viruses. Bacteriophages have been identified as potential indicators or surrogates for human enteric viruses due to their similarities in morphology, behaviour in water environments and resistance to disinfectant treatments. The somatic coliphages, male-specific RNA coliphages (FRNA coliphages) and the bacteriophages of Bacteroides are the groups recognised as most suitable for water and shellfish testing. In this review, we discuss the rationale and supporting evidence for the application of bacteriophages as surrogates for human enteric viruses in shellfish under a variety of conditions. There is some evidence to support the validity of using bacteriophage levels to indicate viral risk in shellfish in highly contaminated sites and following adverse sewage events. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  7. The bivalve Neithea from the Cretaceous of Brazil

    Science.gov (United States)

    de Jesus Andrade, Edilma; Seeling, Jens; Bengtson, Peter; Souza-Lima, Wagner

    2004-09-01

    On the basis of new collections from the Sergipe and Camamu (Bahia) basins, revision of previously described material from the Pernambuco-Paraíba Basin and a reassessment of previous descriptions, five species of the pectinid bivalve Neithea are described from the Cretaceous of northeastern Brazil: N. ( N.) alpina (d'Orbigny, 1847) from the Albian of the Camamu Basin; N. ( N.) coquandi (Peron, 1877) from the Aptian-Cenomanian of the Sergipe Basin, the Albian of the Camamu Basin, broadly mid-Cretaceous beds of the Tucano Sul Basin (Bahia), and the Cenomanian of the São Luís Basin (Maranhão); N. ( N.) hispanica (d'Orbigny, 1850) from the Albian-lower Turonian of the Sergipe Basin; N. ( N.) bexarensis (Stephenson, 1941) from the Campanian of the Pernambuco-Paraíba Basin; N. ( Neithella) notabilis (Münster in Goldfuss, 1833) from the Cenomanian of the Sergipe Basin. All species show a wide geographical distribution, in sharp contrast to previous studies that have indicated a highly endemic mollusc fauna in the Cretaceous of Brazil.

  8. Changing restoration rules: exotic bivalves interact with residence time and depth to control phytoplankton productivity

    Science.gov (United States)

    Lucas, Lisa V.; Thompson, Janet K.

    2012-01-01

    Non-native species are a prevalent ecosystem stressor that can interact with other stressors to confound resource management and restoration. We examine how interactions between physical habitat attributes and a particular category of non-native species (invasive bivalves) influence primary production in aquatic ecosystems. Using mathematical models, we show how intuitive relationships between phytoplankton productivity and controllable physical factors (water depth, hydraulic transport time) that hold in the absence of bivalves can be complicated—and even reversed—by rapid bivalve grazing. In light-limited environments without bivalves, shallow, hydrodynamically “slow” habitats should generally have greater phytoplankton biomass and productivity than deeper, “faster” habitats. But shallower, slower environments can be less productive than deeper, faster ones if benthic grazing is strong. Moreover, shallower and slower waters exhibit a particularly broad range of possible productivity outcomes that can depend on whether bivalves are present. Since it is difficult to predict the response of non-native bivalves to habitat restoration, outcomes for new shallow, slow environments can be highly uncertain. Habitat depth and transport time should therefore not be used as indicators of phytoplankton biomass and production where bivalve colonization is possible. This study provides for ecosystem management a particular example of a broad lesson: abiotic ecosystem stressors should be managed with explicit consideration of interactions with other major (including biotic) stressors. We discuss the applicability and management implications of our models and results for a range of aquatic system types, with a case study focused on the Sacramento-San Joaquin Delta (California, USA). Simple mathematical models like those used here can illuminate interactions between ecosystem stressors and provide process-based guidance for resource managers as they develop strategies

  9. Determination of the recovery efficiency of cryptosporidium oocysts and giardia cysts from seeded bivalve mollusks.

    Science.gov (United States)

    Schets, Franciska M; van den Berg, Harold H J L; de Roda Husman, Ana Maria

    2013-01-01

    The intestinal parasites Cryptosporidium and Giardia are transmitted by water and food and cause human gastroenteritis. Filter-feeding bivalve mollusks, such as oysters and mussels, filter large volumes of water and thus concentrate such pathogens, which makes these bivalves potential vectors of disease. To assess the risk of infection from consumption of contaminated bivalves, parasite numbers and parasite recovery data are required. A modified immunomagnetic separation (IMS) procedure was used to determine Cryptosporidium oocyst and Giardia cyst numbers in individually homogenized oysters (Crassostrea gigas) and mussels (Mytilus edulis). About 12% of the commercial bivalves were positive, with low (oo)cyst numbers per specimen. The recovery efficiency of the IMS procedure was systematically evaluated. Experiments included seeding of homogenized bivalves and whole animals with 100 to 1,000 (oo)cysts. Both seeding procedures yielded highly variable recovery rates. Median Cryptosporidium recoveries were 7.9 to 21% in oysters and 62% in mussels. Median Giardia recoveries were 10 to 25% in oysters and 110% in mussels. Giardia recovery was significantly higher than Cryptosporidium recovery. (Oo)cysts were less efficiently recovered from seeded whole animals than from seeded homogenates, with median Cryptosporidium recoveries of 5.3% in oysters and 45% in mussels and median Giardia recoveries of 4.0% in oysters and 82% in mussels. Both bivalve homogenate seeding and whole animal seeding yielded higher (oo)cyst recovery in mussels than in oysters, likely because of the presence of less shellfish tissue in IMS when analyzing the smaller mussels compared with the larger oysters, resulting in more efficient (oo)cyst extraction. The data generated in this study may be used in the quantitative assessment of the risk of infection with Cryptosporidium or Giardia associated with the consumption of raw bivalve mollusks. This information may be used for making risk management

  10. First evidence of immunomodulation in bivalves under seawater acidification and increased temperature.

    Directory of Open Access Journals (Sweden)

    Valerio Matozzo

    Full Text Available Water acidification, temperature increases and changes in seawater salinity are predicted to occur in the near future. In such a global climate change (GCC scenario, there is growing concern for the health status of both wild and farmed organisms. Bivalve molluscs, an important component of coastal marine ecosystems, are at risk. At the immunological level, the ability of an organism to maintain its immunosurveillance unaltered under adverse environmental conditions may enhance its survival capability. To our knowledge, only a few studies have investigated the effects of changing environmental parameters (as predicted in a GCC scenario on the immune responses of bivalves. In the present study, the effects of both decreased pH values and increased temperature on the important immune parameters of two bivalve species were evaluated for the first time. The clam Chamelea gallina and the mussel Mytilus galloprovincialis, widespread along the coast of the Northwestern Adriatic Sea, were chosen as model organisms. Bivalves were exposed for 7 days to three pH values (8.1, 7.7 and 7.4 at two temperatures (22 and 28°C. Three independent experiments were carried out at salinities of 28, 34 and 40 PSU. The total haemocyte count, Neutral Red uptake, haemolymph lysozyme activity and total protein levels were measured. The results obtained demonstrated that tested experimental conditions affected significantly most of the immune parameters measured in bivalves, even if the variation pattern of haemocyte responses was not always linear. Between the two species, C. gallina appeared more vulnerable to changing pH and temperature than M. galloprovincialis. Overall, this study demonstrated that climate changes can strongly affect haemocyte functionality in bivalves. However, further studies are needed to clarify better the mechanisms of action of changing environmental parameters, both individually and in combination, on bivalve haemocytes.

  11. Bio-accumulation kinetics of radioruthenium in marine bivalves. Laboratory study

    International Nuclear Information System (INIS)

    Mu, D.H.; Yan, S.P.; Gu, Y.J.; Li, D.J.; Du, J.Z.

    2007-01-01

    Three kinds of marine bivalves (wild Saccostrea cucullata, aquacultured Perna viridis and aquacultured Pinctada martens), collected from Daya Bay, the South China Sea, were used to investigate the bio-accumulation of radioruthenium in the glass aquarium with natural seawater (pH 8.20, 35 per mille salinity, filtered by 0.45 μm) at ambient temperature under laboratory feeding conditions. The experimental results show that the stead-state of biology concentration factor (BCF, ml/g) of radioruthenium was approached around 6 days for most species of bivalves. The values of BCF in shells are the highest in organs all the three bivalves. The orders of BCF values (ml x g -1 ) are as: Perna viridis (33.2) < Saccostrea cucullata (47.0) < Pinctada martensi (208.4) for shells and Saccostrea cucullata (1.5) < Pinctada martensi (2.2) ∼ Perma viridis (2.4) for soft tissues, respectively, after exposed for 14 days. The rate constants of uptake and elimination of radioruthenium on marine bivalves were also discussed by first-order kinetics model. The Pinctada martensi may be applicable to be an indictor for monitoring radioruthenium among the three bivalves. (author)

  12. The earliest post-paleozoic freshwater bivalves preserved in coprolites from the karoo basin, South Africa.

    Science.gov (United States)

    Yates, Adam M; Neumann, Frank H; Hancox, P John

    2012-01-01

    Several clades of bivalve molluscs have invaded freshwaters at various times throughout Phanerozoic history. The most successful freshwater clade in the modern world is the Unionoida. Unionoids arose in the Triassic Period, sometime after the major extinction event at the End-Permian boundary and are now widely distributed across all continents except Antarctica. Until now, no freshwater bivalves of any kind were known to exist in the Early Triassic. Here we report on a faunule of two small freshwater bivalve species preserved in vertebrate coprolites from the Olenekian (Lower Triassic) of the Burgersdorp Formation of the Karoo Basin, South Africa. Positive identification of these bivalves is not possible due to the limited material. Nevertheless they do show similarities with Unionoida although they fall below the size range of extant unionoids. Phylogenetic analysis is not possible with such limited material and consequently the assignment remains somewhat speculative. Bivalve molluscs re-invaded freshwaters soon after the End-Permian extinction event, during the earliest part of the recovery phase during the Olenekian Stage of the Early Triassic. If the specimens do represent unionoids then these Early Triassic examples may be an example of the Lilliput effect. Since the oldest incontrovertible freshwater unionoids are also from sub-Saharan Africa, it is possible that this subcontinent hosted the initial freshwater radiation of the Unionoida. This find also demonstrates the importance of coprolites as microenvironments of exceptional preservation that contain fossils of organisms that would otherwise have left no trace.

  13. Trace Fossil Evidence of Trematode-Bivalve Parasite-Host Interactions in Deep Time.

    Science.gov (United States)

    Huntley, John Warren; De Baets, Kenneth

    2015-01-01

    Parasitism is one of the most pervasive phenomena amongst modern eukaryotic life and yet, relative to other biotic interactions, almost nothing is known about its history in deep time. Digenean trematodes (Platyhelminthes) are complex life cycle parasites, which have practically no body fossil record, but induce the growth of characteristic malformations in the shells of their bivalve hosts. These malformations are readily preserved in the fossil record, but, until recently, have largely been overlooked by students of the fossil record. In this review, we present the various malformations induced by trematodes in bivalves, evaluate their distribution through deep time in the phylogenetic and ecological contexts of their bivalve hosts and explore how various taphonomic processes have likely biased our understanding of trematodes in deep time. Trematodes are known to negatively affect their bivalve hosts in a number of ways including castration, modifying growth rates, causing immobilization and, in some cases, altering host behaviour making the host more susceptible to their own predators. Digeneans are expected to be significant agents of natural selection. To that end, we discuss how bivalves may have adapted to their parasites via heterochrony and suggest a practical methodology for testing such hypotheses in deep time. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. The earliest post-paleozoic freshwater bivalves preserved in coprolites from the karoo basin, South Africa.

    Directory of Open Access Journals (Sweden)

    Adam M Yates

    Full Text Available BACKGROUND: Several clades of bivalve molluscs have invaded freshwaters at various times throughout Phanerozoic history. The most successful freshwater clade in the modern world is the Unionoida. Unionoids arose in the Triassic Period, sometime after the major extinction event at the End-Permian boundary and are now widely distributed across all continents except Antarctica. Until now, no freshwater bivalves of any kind were known to exist in the Early Triassic. PRINCIPAL FINDINGS: Here we report on a faunule of two small freshwater bivalve species preserved in vertebrate coprolites from the Olenekian (Lower Triassic of the Burgersdorp Formation of the Karoo Basin, South Africa. Positive identification of these bivalves is not possible due to the limited material. Nevertheless they do show similarities with Unionoida although they fall below the size range of extant unionoids. Phylogenetic analysis is not possible with such limited material and consequently the assignment remains somewhat speculative. CONCLUSIONS: Bivalve molluscs re-invaded freshwaters soon after the End-Permian extinction event, during the earliest part of the recovery phase during the Olenekian Stage of the Early Triassic. If the specimens do represent unionoids then these Early Triassic examples may be an example of the Lilliput effect. Since the oldest incontrovertible freshwater unionoids are also from sub-Saharan Africa, it is possible that this subcontinent hosted the initial freshwater radiation of the Unionoida. This find also demonstrates the importance of coprolites as microenvironments of exceptional preservation that contain fossils of organisms that would otherwise have left no trace.

  15. Zebra mussel infestation of unionid bivalves (Unionidae) in North America

    Science.gov (United States)

    Schloesser, Don W.; Nalepa, Thomas F.; Mackie, Gerald L.

    1996-01-01

    In 1989, zebra mussels received national attention in North America when they reached densities exceeding 750,000/m2 in a water withdrawal facility along the shore of western Lake Erie of the Laurentian Great Lakes. Although water withdrawal problems caused by zebra mussels have been of immediate concern, ecological impacts attributed to mussels are likely to be the more important long-term issue for surface waters in North America. To date, the epizoic colonization (i.e., infestation) of unionid bivalve mollusks by zebra mussels has caused the most direct and severe ecological impact. Infestation of and resulting impacts caused by zebra mussels on unionids in the Great Lakes began in 1988. By 1990, mortality of unionids was occurring at some locations; by 1991, extant populations of unionids in western Lake Erie were nearly extirpated; by 1992, unionid populations in the southern half of Lake St. Clair were extirpated; by 1993, unionids in widely separated geographic areas of the Great Lakes and the Mississippi River showed high mortality due to mussel infestation. All infested unionid species in the Great Lakes (23) have become infested and exhibited mortality within two to four years after heavy infestation began. Data indicate that mean zebra mussel densities >5,000–6,000/m2 and infestation intensities >100-200/unionid in the presence of heavy zebra mussel recruitment results in near total mortality of unionids. At present, all unionid species in rivers, streams, and akes that sympatrically occur with zebra mussels have been infested and, in many locations, negatively impacted by zebra mussels. We do not know the potential consequences of infestation on the 297 unionid species found in North America, but believe zebra mussels pose an immediate threat to the abundance and diversity of unionids.

  16. Gastrointestinal Manifestations of Cystic Fibrosis

    Science.gov (United States)

    2016-01-01

    Cystic fibrosis has historically been considered a pulmonary disease, but with the increasing life expectancy of these patients, gastrointestinal manifestations are becoming more important. Furthermore, nutritional status is closely linked to pulmonary function and, thus, overall mortality. This article discusses gastrointestinal manifestations (which involve nutritional, pancreatic, hepatobiliary, and, in particular, gastrointestinal tract issues) of cystic fibrosis as well as management of the disease. In addition, the article discusses studies that have been critical to our understanding of gastrointestinal manifestations of cystic fibrosis. PMID:27330503

  17. Cardiovascular manifestations of subarachnoid haemorrhage

    Directory of Open Access Journals (Sweden)

    Sethuraman Manikandan

    2017-01-01

    Full Text Available Subarachnoid haemorrhage (SAH is one of the devastating conditions, especially the aneurysmal bleed which has high mortality as well as morbidity. The mortality and morbidity caused by SAH have been recognised to be caused by both neurological and systemic causes. The alterations in systemic and other organ damage could cause death in up to 40% of SAH patients. Among the systemic manifestations, cardiovascular and respiratory complications increase hospitalisation and worsen the outcome. The main pathophysiological mechanism is the increased sympathetic activation causing myocardial necrosis. Various cardiovascular manifestations range from electrocardiogram changes to myocardial ischaemia, cardiac failure and arrhythmias. This review deals with the cardiac manifestations in SAH patients.

  18. In situ method for measurements of community clearance rate on shallow water bivalve populations

    DEFF Research Database (Denmark)

    Hansen, Benni W.; Dolmer, Per; Vismann, Bent

    2011-01-01

    with an air lift connected to a SCUBA diver pressure tank generating a continuous and gentle water circulation. This ensures a complete mixture of suspended particles, and thereby, a maximum filtration by the bivalves. An in situ fluorometer was mounted to record plant pigment reduction due to mussel...... clearance in real-time. To calibrate the in situ fluorometer triplicate water samples were obtained initially in each of the bivalve filtration measurements. The water samples were filtrated, extracted, and later analyzed for plant pigment concentration on a laboratory spectrophotometer. The main conclusion......An open-top chamber was designed for measuring ambient community clearance rate on undisturbed bivalve populations in the field. The chamber was pressed 5-10 cm down in the sediment on the mussel bed. It holds approximately 30-40 cm water column equal to a volume of 43-77 L. It was provided...

  19. The bivalves from the Scotia Arc islands: species richness and faunistic affinities

    Directory of Open Access Journals (Sweden)

    Diego G. Zelaya

    2005-12-01

    Full Text Available Species richness of the shallow-water bivalves from the Scotia Arc islands was studied on the basis of new collections and by reviewing extant information. Seventy-three species are recognised from the entire area. South Georgia, the South Orkney Islands and the South Shetland Islands were similar in species richness to the Antarctic Weddell sector. New records for 51 bivalve species are provided and the presence of 18 undescribed species is reported. The faunistic similarity of the islands of the Scotia Arc to the Magellan region and the Antarctic Weddell sector is re-examined. These islands show a high similarity to the Antarctic Weddell sector (49 to 85% and a low similarity to the Magellan region (12 to 32%. Evidence from bivalves clearly supports the placement of the Scotia Arc islands within the Antarctic region.

  20. Dioxin-like chemicals in bivalves and sediment collected from around Australia

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, J.F.; Muller, R.; Goudkamp, K. [EnTox, The University of Queensland, Brisbane (AU)] (and others)

    2004-09-15

    The aquatic environment is a significant sink for persistent organic pollutants including dioxin-like chemicals. Besides continuous investigations into sources of higher chlorinated PCDD that have initially been found in soils, and later in dugong and sediments little is known about the levels of dioxin-like chemicals in Australia's aquatic environment. In 2002 the National Dioxin Program (NDP) was commissioned by the Department of Environment and Heritage, Australia. One focus of the NDP was to evaluate background levels of dioxin-like chemicals in Australia's environment. One component of the 'Environmental Levels' project aimed to identify dioxinlike chemicals in the aquatic environment including bivalves collected in both marine, estuarine and freshwater systems. Here we report results from the NDP aquatic study with a particular emphasis on the levels of dioxin-like chemicals in bivalves and sediments respectively in areas from where the bivalves were collected.

  1. Arsenic and trace metals in commercially important bivalves, Anadara granosa and Paphia undulata

    Energy Technology Data Exchange (ETDEWEB)

    Mat, I. (Univ. of Malaya, Kuala Lumpur (Malaysia))

    1994-06-01

    The semi-culture of marine bivalves particularly Anadara granosa is of considerable economic importance in Malaysia. Currently, about 4-5000 ha of mudflats along the west coast are utilized for this purpose. Therefore, contamination of the highly productive mudflats with heavy metals tend to be accumulated in the filter feeding organisms such as bivalve molluscs which often serve as important environmental sinks of heavy metals. Bivalve molluscs, A. granosa and Paphia undulata are commercially important seafoods and popular among the locals in Malaysia. With this point in mind, it is intended to evaluate the concentration levels of arsenic as well as trace metals (Co, Cu, Ni, Cd, Zn, Cr and Pb) in both species derived from retail outlets in the city of Kuala Lumpur. Although this analysis may not indicate the site of capture but may act as a direct check on the contamination of seafoods available to the consumers. 17 refs., 2 tabs.

  2. SHRIMP (CRANGON-CRANGON L) BROWSING UPON SIPHON TIPS INHIBITS FEEDING AND GROWTH IN THE BIVALVE MACOMA-BALTHICA (L)

    NARCIS (Netherlands)

    KAMERMANS, P; HUITEMA, HJ

    1994-01-01

    The influence of siphon browsing on the feeding behaviour and growth of Macoma balthica, a deposit-feeding bivalve, was studied in three manipulative experiments. Browsing was simulated by removing part of the inhalant siphon with scissors, or studied by exposing the bivalves to shrimps (Crangon

  3. An integrated ecosystem approach for assessing the potential role of cultivated bivalve shells as part of the carbon trading system

    NARCIS (Netherlands)

    Filgueira, R.; Byron, C.J.; Comeau, L.A.; Jansen, H.M.; Smaal, A.C.

    2015-01-01

    The role of bivalve mariculture in the CO2 cycle has been commonly evaluated as the balance between respiration, shell calcium carbonate sequestration and CO2 release during biogenic calcification. However, this approach neglects the ecosystem implications of cultivating bivalves at high densities,

  4. Oral Manifestations of Eating Disorders

    OpenAIRE

    Neeta Misra; Anshul Mehra; Pradyuman Misra; Jaya Mehra

    2010-01-01

    Eating disorders are potentially life-threatening disorders. In this article, we discuss the oral manifestations of eating disorders so as to enable dental practitioners to recognize the effects of eating disorders and to manage the patients with eating disorders.

  5. Skin Manifestations of Endocrine Diseases.

    Science.gov (United States)

    Demirkesen, Cuyan

    2015-01-01

    Endocrine diseases may result in changes in cutaneous function and morphology, which cause various skin manifestations, including nonspecific or pathognomonic signs. Some of these manifestations are already known dermatologic diseases with only increased frequency in this patient group. As a result the skin may the play role of a screen displaying endocrine disorders, either due to hormone excess or deficiency. Awareness of the skin manifestations may permit prompt and adequate approach to the patients, and therefore facilitate the early diagnosis of the endocrine disease and even be life saving. Some of these manifestations may be recognized clinically, but sometimes they need to be confirmed histopathologically. In this article, many endocrine diseases and their associated skin lesions will be reviewed briefly.

  6. Nail manifestations in pemphigus vulgaris

    Directory of Open Access Journals (Sweden)

    Cahali Juliana Burihan

    2002-01-01

    Full Text Available Nail involvement in pemphigus vulgaris is rare. We describe 5 patients with pemphigus vulgaris presenting nail involvement. In this disease, nail manifestations present, by order of frequency, as chronic paronychia, onychomadesis, onycholysis, Beau's lines and trachyonychia. All our 5 cases presented with paronychia, and 1 of them also had Beau's lines. Treatment with prednisone and/or cyclophosphamide controlled mucocutaneous and nail manifestations in all cases.

  7. Bivalve aquaculture-environment interactions in the context of climate change.

    Science.gov (United States)

    Filgueira, Ramón; Guyondet, Thomas; Comeau, Luc A; Tremblay, Réjean

    2016-12-01

    Coastal embayments are at risk of impacts by climate change drivers such as ocean warming, sea level rise and alteration in precipitation regimes. The response of the ecosystem to these drivers is highly dependent on their magnitude of change, but also on physical characteristics such as bay morphology and river discharge, which play key roles in water residence time and hence estuarine functioning. These considerations are especially relevant for bivalve aquaculture sites, where the cultured biomass can alter ecosystem dynamics. The combination of climate change, physical and aquaculture drivers can result in synergistic/antagonistic and nonlinear processes. A spatially explicit model was constructed to explore effects of the physical environment (bay geomorphic type, freshwater inputs), climate change drivers (sea level, temperature, precipitation) and aquaculture (bivalve species, stock) on ecosystem functioning. A factorial design led to 336 scenarios (48 hydrodynamic × 7 management). Model outcomes suggest that the physical environment controls estuarine functioning given its influence on primary productivity (bottom-up control dominated by riverine nutrients) and horizontal advection with the open ocean (dominated by bay geomorphic type). The intensity of bivalve aquaculture ultimately determines the bivalve-phytoplankton trophic interaction, which can range from a bottom-up control triggered by ammonia excretion to a top-down control via feeding. Results also suggest that temperature is the strongest climate change driver due to its influence on the metabolism of poikilothermic organisms (e.g. zooplankton and bivalves), which ultimately causes a concomitant increase of top-down pressure on phytoplankton. Given the different thermal tolerance of cultured species, temperature is also critical to sort winners from losers, benefiting Crassostrea virginica over Mytilus edulis under the specific conditions tested in this numerical exercise. In general, it is

  8. A Darriwilian (Middle Ordovician bivalve-dominated molluscan fauna from the Stairway Sandstone, Amadeus Basin, central Australia

    Directory of Open Access Journals (Sweden)

    Kristian G. Jakobsen

    2016-12-01

    Full Text Available A bivalve-dominated molluscan fauna is described from the Darriwilian (Middle Ordovician Stairway Sandstone, Amadeus Basin, central Australia. The fauna comprises 16 species of bivalves and rostroconchs plus six gastropod species which are treated under open nomenclature. Two new bivalves, Sthenodonta paenesymmetrica sp. nov. and Modiolopsis pojetai sp. nov., are described. The relatively low-diverse molluscan fauna constitutes around 62% of the total benthic macrofauna. Approximately 75% of the molluscs comprise bivalves, especially nuculoids, which were biogeographically restricted to low latitudes during the Ordovician. The molluscan assemblage displays a very high degree of endemism at species level, though the bivalve Sthenodonta eastii also occurs in the Georgina Basin farther to the northeast. This indicates a possible marine connective seaway between the Georgina and Amadeus basins during the Darriwilian. Nuculites, Cyrtodonta, and Modiolopsis are cosmopolitan and previously reported from North China, Avalonia, and Southern Gondwana.

  9. An integrated ecosystem approach for assessing the potential role of cultivated bivalve shells as part of the carbon trading system

    DEFF Research Database (Denmark)

    Filgueira, Ramón; Byron, C.J.; Comeau, L.A.

    2015-01-01

    , e.g. the impact on phytoplankton dynamics and benthic-pelagic coupling, which can significantly contribute to the CO2 cycle. Therefore, an ecosystem approach that accounts for the trophic interactions of bivalve aquaculture, including dissolved and particulate organic and inorganic carbon cycling......, is needed to provide a rigorous assessment of the role of bivalve mariculture in the CO2 cycle. On the other hand, the discussion about the inclusion of shells of cultured bivalves into the carbon trading system should be framed in the context of ecosystem goods and services. Humans culture bivalves...... with the aim of producing food, not sequestering CO2 in their shells, therefore the main ecosystem good provided by bivalve aquaculture is meat production, and shells should be considered as by-products of this human activity. This reasoning is key to split the CO2 released due to respiration between meat...

  10. Morphometric Studies on Anodonta Anatine Bivalve Population from the Dognecea Lake

    Directory of Open Access Journals (Sweden)

    Marian Bura

    2011-10-01

    Full Text Available In the Dognecea Lake, near town Bocsa in Caras-Severin county a strong bivalve population has been discovered from the duck mussel specie (Anodonta anatina. Harvested individuals were transported to the Aquaculture laboratory where measurements and correct identification was made. This specie is considered endangered but in Banat area, especially in the Dognecea Lake it is well represented, having an ecological importance, but the bivalve can have an economical importance too, due to the high percentage of edible part of 56.5%.

  11. Temporal and spatial variations in iron concentrations of tropical bivalves during dredging event

    Digital Repository Service at National Institute of Oceanography (India)

    Brown, B.E.; Jayakumar, A.

    differs with respect to location, with highest iron levels being recorded in bivalves living in the vicinity of a tin-ore dressing plant. Temporal elevations in bivalve iron con- centrations closely parallel times of dredging activity and iron... causing con- siderable mortality to reef corals at this site (Brown et al., in press). In mid-1988 cracks appeared in the holding wall of the settling lagoon of the ore-dressing plant and iron- enriched liquor drained on to the reef flat at site A...

  12. Marine bivalve feeding strategy, radiocarbon ages and stable isotopes in Scottish coastal waters

    Science.gov (United States)

    Lo Giudice Cappelli, Elena; Austin, William

    2017-04-01

    Marine bivalve molluscs have been widely used for palaeoenvironmental reconstructions as their carbonate provides a direct chronology of environmental change through radiocarbon dating, and their shell composition, particularly with regard to their oxygen and carbon stable isotopes, is likely to reflect ambient seawater conditions. However, stable isotope signatures of marine bivalve shells are difficult to interpret, as shell formation can be influenced by secondary factors such as metabolic processes and feeding strategies. In radiocarbon ages, uncertainty is introduced as bivalves inhabit a range of ecological niches which may be of significance in the case of deep borrowing and deposit feeding bivalves, as they could incorporate older carbon in their shells, resulting in apparent older ages than the true age of the dissolved inorganic carbon in the overlying seawater. To discriminate between the different factors influencing the composition of marine molluscs' shells, we measured radiocarbon ages, oxygen and carbon stable isotopes in nine species of marine bivalves having different known feeding strategies and inhabiting a number of ecological niches; all shells being live-collected (between 1923-1925) from six localities around the Scottish coast, a wider context than has been previously undertaken. Our results show that in situ variability (i.e.: replicate measurements of the same species at the same location) is generally low for both stable isotope analyses and radiocarbon dates, indicating good accuracy of the measurements. Intra-species (i.e.: same species - different location) and inter-species (i.e.: different species - same location) variability is significant in stable isotopes measurements, meaning that marine bivalve shells do record changes in the local environment and are sensitive to different feeding strategies and ecological settings. In contrast, radiocarbon ages do not change with location and are not sensitive to molluscs' diets or

  13. Otimização do processo de depuração de moluscos bivalves

    OpenAIRE

    Correia, Maria Helena Oliveira Casimiro

    2016-01-01

    A contaminação microbiológica de moluscos bivalves constitui uma das principais preocupações inerentes à segurança alimentar desta importante fonte de receitas para a economia portuguesa. Os bivalves capturados ou produzidos em zonas estuarinas ou lagunares devem passar por um processo de depuração, para redução dos níveis de contaminação microbiológica, antes da sua comercialização. Este trabalho teve como principal objetivo o desenvolvimento de sistemas modulares de dep...

  14. Skin manifestations of Cushing's syndrome.

    Science.gov (United States)

    Stratakis, Constantine A

    2016-09-01

    Among the most common diagnostic manifestations of Cushing's syndrome (CS) are those involving the skin; they include violaceous striae, facial acne, hirsutism, acanthosis nigricans (AN), fungal infections, hyperpigmentation (Hp) and easy bruisability. Fortunately, most resolve within a year or two after cure of CS, although light-colored striae can persist for years depending on the age of the patients. AN, Hp, and bruisability usually resolve within months after cure in almost all ages. Facial plethora (along with acne and other facial skin changes) is a typical sign of CS that is due to increased perfusion. It resolves immediately after curative therapy of CS. Typically, the severity of the manifestations does not correlate with the biochemical indices of the disease, pointing to age, gender, genetic and skin-type differences that determine the cutaneous manifestations of CS.

  15. Cutaneous manifestations of primary immunodeficiency

    Directory of Open Access Journals (Sweden)

    Safa Abdelhakim

    2017-01-01

    Full Text Available Primary immunodeficiency diseases (PIDs are a group of rare, chronic disorders with deficient or malfunctioning immune system. It commonly affects the hematopoietic system, with skin the second most affected organ. Skin involvement is observed in half of pediatric PID cases and often precedes the final diagnosis. Skin infections and eczemas are the two most common manifestations in PID.[1] Skin manifestations associated with PIDs can be of infectious and noninfectious causes. Common noninfectious causes are eczema, erythroderma, cutaneous granulomas, dysplasia, vasculitis, and telangiectasia. It is important to be aware of skin manifestations in pediatric patients as early detection of PID may aid in the management of serious immunologic conditions and prevent associated morbidity and mortality.

  16. Modiolarca lateralis (Pteryomorphia: Mytilidae: bivalve associated to six species of ascidians from Bocas del Toro, Panama

    Directory of Open Access Journals (Sweden)

    Juan I Cañete

    2013-11-01

    Full Text Available We describe the presence of the bivalve Modiolarca lateralis (Say, 1822 in six tropical ascidians Ascidia curvata, A. sydneiensis, A. panamensis, A. interrupta, Herdmania pallida and Polycarpa spongiabilis collected at depths of 1-3 m on coral reefs, mangrove roots and dock supports in Almirante Bay, Bocas del Toro, Panama (9°18'N, 82°13'W during June-July 2011. Bivalve prevalence varied between 9-30% across species, but was mainly associated with A. panamensis, P. spongiabilis and A. interrupta. Prevalence seems to be influenced by tunic thickness rather than by the ascidian size. Bivalves varied in size (0.6-11 mm shell length, with the smallest individual found in A. sydneiensis. There were only one or two bivalves per ascidians, although a maximum of 18 was found in one A. panamensis. M. lateralis seems to behave similarly to its temperate counterparts: it has a variety of hosts, occurs mainly in the anterior region of the ascidians, and has a variable abundance per host.

  17. Consumption of freshwater bivalves by muskrats in the Green River, Kentucky

    Science.gov (United States)

    Hersey, Kimberly Asmus; Clark, Joseph D.; Layzer, James B.

    2013-01-01

    Muskrats (Ondatra zibethicus) are known to prey on freshwater bivalves (mussels and clams) and can negatively impact imperiled mussel species. However, factors that influence muskrat predation on bivalves are poorly understood. We evaluated the feeding ecology of muskrats in the Green River, Kentucky, by using stable isotope analysis of muskrat hair samples and by monitoring bivalve shell deposition at muskrat middens. Bayesian mixing-model analysis of stable isotope δ15N and δ13C ratios revealed that the median muskrat biomass derived from bivalves was 51.4% (5th and 95th percentiles were 39.1 to 63.4%, respectively), a much higher dietary proportion than previously reported. Shell depositions by muskrats at middens decreased with the availability of seasonal emergent vegetation, suggesting that the consumption of animal matter is in response to a scarcity of plant foods, perhaps exacerbated by the altered flow regimes on the Green River. Our results add to the growing body of evidence that muskrats have the potential to impact mussel population growth and recovery in some environments.

  18. Understanding the implications of a changing environment on harvested bivalve populations using habitat suitability models

    Science.gov (United States)

    Habitat suitability models are useful to forecast how environmental change may affect the abundance or distribution of species of interest. In the case of harvested bivalves, those models may be used to estimate the vulnerability of this valued ecosystem good to stressors. Using ...

  19. BIVALVE BIOGEOGRAPHIC DISTRIBUTIONS, ABUNDANCES, AND CLIMATE VULNERABILITY FROM THE BEAUFORT SEA TO THE GULF OF CALIFORNIA

    Science.gov (United States)

    As part of an U.S. EPA/USGS project to predict the relative vulnerability of near-coastal species to climate change along the Pacific Coast, we have synthesized the biogeographic distributions and abundances of bivalves found in depths <200 m. We have included the twelve &ldqu...

  20. EMBATTLED BIVALVES: BIOGEOGRAPHIC DISTRIBUTIONS AND ABUNDANCES FROM THE BEAUFORT SEA TO THE GULF OF CALIFORNIA

    Science.gov (United States)

    As part of an EPA/USGS project to predict the relative vulnerability of near-coastal species to climate change, we have synthesized in a web-based tool, the Coastal Biogeographic Risk Analysis Tool (CBRAT), the biogeographic distributions and abundances of bivalves, found in dept...

  1. An ecosystem-based approach and management framework for the integrated evaluation of bivalve aquaculture impacts

    NARCIS (Netherlands)

    Cranford, P.J.; Kamermans, P.; Krause, G.H.M.; Mazurie, J.

    2012-01-01

    An ecosystem-based approach to bivalve aquaculture management is a strategy for the integration of aquaculture within the wider ecosystem, including human aspects, in such a way that it promotes sustainable development, equity, and resilience of ecosystems. Given the linkage between social and

  2. Uranium uptake by the freshwater bivalve Corbicula fluminea: links between speciation, bioavailability and effects

    Energy Technology Data Exchange (ETDEWEB)

    Adam, C.; Tran, D.; Simon, O.; Fournier, E.; Denison, D.; Massabuau, J.C.; Garnier-Laplace, J. [CEA Cadarache (DEI/SECRE/LRE), Laboratory of Radioecology and Ecotoxicology, Institute for Radioprotection and Nuclear Safety, 13 - Saint-Paul-lez-Durance (France)

    2004-07-01

    Within the framework of ENVIRHOM research programme, dealing with the chronic low-level exposure of ecosystems to radionuclides, a set of experiments was conducted to investigate the links between speciation, bioavailability and effects of uranium in the bivalve Corbicula fluminea. Short-term uptake experiments were performed to link speciation to bioavailability, while evaluating the competitive effect of cations (Ca{sup 2+}, Mg{sup 2+} and H{sup +}) and the influence of uranium ligands in solution. Longer-term experiments were also performed to gain knowledge on distribution and uptake mechanisms. The effect of uranium on the bivalve behaviour was studied through (1) the valve movement activity, recorded by means of impedance measurements taken with two electrodes stuck on each shell of the bivalve, the measured current varying according to the distance between the electrodes and (2) the ventilation rate, whose measurement is based on the calculation of the volume of water cleared of algae per unit time in a transiently closed system. Effect Concentrations giving a closure response for p percent of the bivalves (ECp), can be calculated from experiments of valve movement activity via a logistic regression model. The main results of these studies will be presented, with a focus on their potential use for operational applications such as monitoring programmes. (author)

  3. Uptake of contaminants of emerging concern by the bivalves Anodonta californiensis and Corbicula fluminea.

    Science.gov (United States)

    Ismail, Niveen S; Müller, Claudia E; Morgan, Rachel R; Luthy, Richard G

    2014-08-19

    Uptake of seven contaminants regularly detected in surface waters and spanning a range of hydrophobicities (log D(ow) -1 to 5) was studied for two species of freshwater bivalves, the native mussel Anodonta californiensis and the invasive clam Corbicula fluminea. Batch systems were utilized to determine compound partitioning, and flow-through systems, comparable to environmental conditions in effluent dominated surface waters, were used to determine uptake and depuration kinetics. Uptake of compounds was independent of bivalve type. Log bioconcentration factor (BCF) values were correlated with log D(ow) for nonionized compounds with the highest BCF value obtained for triclocarban (TCC). TCC concentrations were reduced in the water column due to bivalve activity. Anionic compounds with low D(ow) values, i.e., clofibric acid and ibuprofen, were not removed from water, while the organic cation propranolol showed biouptake similar to that of TCC. Batch experiments supported compound uptake patterns observed in flow-through experiments. Contaminant removal from water was observed through accumulation in tissue or settling as excreted pseudofeces or feces. The outcomes of this study indicate the potential utility of bivalve augmentation to improve water quality by removing hydrophobic trace organic compounds found in natural systems.

  4. Filter-feeding bivalves can remove avian influenza viruses from water and reduce infectivity

    Science.gov (United States)

    Avian influenza (AI) viruses are transmitted within wild aquatic bird populations through an indirect fecal-oral route involving fecal-contaminated water. In this study, the influence of filter-feeding bivalves, Corbicula fluminea, on the infectivity of AI virus in water was examined. A single cla...

  5. Distribution of DTHS3 satellite DNA across 12 bivalve species Eva ...

    Indian Academy of Sciences (India)

    Windows User

    In this work, characterization of DTHS3 satellite DNA was further expanded within the Class. Bivalvia. Monomer variants of DTHS3 satDNA were compared in 12 bivalve species belonging to two different Subclasses, Heterodonta and Pteriomorphia. This satDNA, whose age is estimated to a minimum of 516 Ma, ...

  6. Estimation of density-dependent mortality of juvenile bivalves in the Wadden Sea.

    Directory of Open Access Journals (Sweden)

    Henrike Andresen

    Full Text Available We investigated density-dependent mortality within the early months of life of the bivalves Macoma balthica (Baltic tellin and Cerastoderma edule (common cockle in the Wadden Sea. Mortality is thought to be density-dependent in juvenile bivalves, because there is no proportional relationship between the size of the reproductive adult stocks and the numbers of recruits for both species. It is not known however, when exactly density dependence in the pre-recruitment phase occurs and how prevalent it is. The magnitude of recruitment determines year class strength in bivalves. Thus, understanding pre-recruit mortality will improve the understanding of population dynamics. We analyzed count data from three years of temporal sampling during the first months after bivalve settlement at ten transects in the Sylt-Rømø-Bay in the northern German Wadden Sea. Analyses of density dependence are sensitive to bias through measurement error. Measurement error was estimated by bootstrapping, and residual deviances were adjusted by adding process error. With simulations the effect of these two types of error on the estimate of the density-dependent mortality coefficient was investigated. In three out of eight time intervals density dependence was detected for M. balthica, and in zero out of six time intervals for C. edule. Biological or environmental stochastic processes dominated over density dependence at the investigated scale.

  7. Validation and comparison of methods for enumeration of faecal coliforms and Escherichia coli in bivalve molluscs

    NARCIS (Netherlands)

    Mooijman KA; Poelman M; Stegeman H; Warmerdam C; Teunis PFM; Roda Husman AM de; RIKILT; MGB

    2007-01-01

    The main result of the validation study to show the equivalence of two methods for the enumeration of faecal coliforms in bivalve molluscs is that the plate count method on Mac Conkey agar was indeed found to be equivalent to the MPN method. Meaning that the Netherlands fulfilled the demands as

  8. Evaluation of the ligand specificity of hemolymph hemoagglutinins and hemolysins of gastropod and bivalve molluscs

    NARCIS (Netherlands)

    Baskakov, AV; Polevshchikov, AV; Kharazova, AD

    2000-01-01

    The study deals with evaluation of ligand specificities of hemoagglutinins and hemolysins of hemolymph of three species of gastropods ( Planorbius corneus, Lymnaea stagnalis, and Achatina fu[ica) and one species of bivalve molluscs (Anodonta cygnea). The hemoagglutinin titer was estimated from

  9. Bivalve grazing, nutrient cycling and phytoplankton dynamics in an estuarine ecosystem

    NARCIS (Netherlands)

    Prins, T.C.

    1996-01-01


    This thesis has considered the impact of the suspension feeding bivalve Mytilusedulis on nutrient cycling and phytoplankton in an estuarine ecosystem. The research was started within the framework of an extensive research project with the

  10. Distribution of DTHS3 satellite DNA across 12 bivalve species Eva ...

    Indian Academy of Sciences (India)

    Windows User

    Long-term conservation vs high sequence divergence: the case of an extraordinarily old satellite DNA in bivalve mollusks. Heredity. 104, 543–551. Salser W., Bowen S., Browne D., el-Adli F., Fedoroff N., Fry K., Heindell H., Paddock G.,. Poon R., Wallace B., Whitcome P. 1976 Investigation of the organization of mammalian.

  11. Callovian-Oxfordian bivalves from central Saudi Arabia: Systematic paleontology and paleobiogeography

    Science.gov (United States)

    Zakhera, Mohamed; El-Hedeny, Magdy; El-Sabbagh, Ahmed; Al Farraj, Saleh

    2017-06-01

    Two hundred and seventy-eight specimens of fossil bivalves were collected from the Tuwaiq Mountain Limestone (Callovian) and the Hanifa Formation (Oxfordian), Central Saudi Arabia. Of all the outcrops studied, the Khashm al Qaddiyah contains the richest assemblage of the bivalves (49%), as regards variety and frequency; followed by Dirab (27%), Jabal al Abakkayn (13%) and Maáshabah (11%). Twenty bivalve species have been identified and systematically described. They belong to fourteen genera, twelve families and nine orders. Among these species, six Callovian species; Grammatodon (Cosmetodon) elongatum (J. Sowerby, 1824), Limea (Pseudolimea) duplicata (Sowerby, 1827), Liostrea multiformis (Koch and Dunker, 1837), Actinostreon marshi (Sowerby, 1814), Eopecten velatus (Goldfuss, 1833) and Ceratomya striata (Sowerby, 1815) and four Callovian-Oxfordian taxa; Musculus (M.) somaliensis (Cox, 1935), Actinostreon erucum (Defrance, 1821), Pholadomya (Ph.) deltoidea Sowerby, 1827 and Ph. (Ph.) socialis Morris and Lycett, 1854 were reported for the first time from the Jurassic deposits of Saudi Arabia. Paleobiogeographically, the studied bivalve assemblage has a dominantly Tethyan character and shows close relationships with Europe, East Africa, India and Iran. In addition, there are considerable links with the Middle East, North Africa and China. No endemic species were recorded from the studied sections.

  12. CYP1A-immunopositive proteins in bivalves identified as cytoskeletal and major vault proteins

    DEFF Research Database (Denmark)

    Grøsvik, Bjørn Einar; Jonsson, Henrik; Rodríguez-Ortega, Manuel J

    2006-01-01

    To identify possible CYP1A-immunopositive proteins in bivalves, we used anti-fish CYP1A antibodies combined with one- and two-dimensional gel electrophoresis and mass spectrometry, and found that two of the main CYP1A-immunopositive proteins in digestive gland of Mytilus edulis, were cytoskeletal...

  13. Mosaic haploid-diploid embryos and polyspermy in the tellinid bivalve Macoma balthica

    NARCIS (Netherlands)

    Luttikhuizen, PC; Pijnacker, LP

    We investigated meiosis, fertilization, and early development in eggs of the tellinid bivalve Macoma balthica (L.), which has external fertilization. Meiosis is standard but polyspermy is found to be very common. In all eight crosses examined, mosaic embryos consisting of a mixture of diploid (2n =

  14. Changes in distribution and decrease in numbers during migration of the bivalve Macoma balthica

    NARCIS (Netherlands)

    Hiddink, J.G.; Wolff, W.J.

    2002-01-01

    The population development of the 1998 year class of the bivalve Macoma balthicd was studied by repeated sampling of a tidal flat area in the eastern Dutch Wadden Sea from May 1998 to August 2000. The juveniles migrated twice, once in mid-1998 from their primary settlement locations in the low sandy

  15. Wood-Boring Bivalves (Mollusca: Teredinidae, Pholadidae) of Pacific coast of Colombia

    International Nuclear Information System (INIS)

    Cantera K, Jaime R

    2010-01-01

    Twelve species of wood-boring bivalves, ten of the family Teredinidae and two of family Pholadidae were collected in mangroves at 6 locations of the Pacific coast of Colombia. This paper presents a brief escription of these species, including size, ecological notes and geographical distribution.

  16. GASTROINTESTINAL MANIFESTATIONS OF MITOCHONDRIAL DYSFUNCTION

    Directory of Open Access Journals (Sweden)

    A. A. Ziganshina

    2016-01-01

    Full Text Available Objective: to highlight the current concepts of gastrointestinal manifestations of mitochondrial dysfunction. The data available in Russian and foreign literature on the gastrointestinal manifestations of mitochondrial dysfunction were analyzed. Functional digestive diseases are common in pediatric practice; however, their etiopathogenesis has not been adequately explored today. According to the literature, impaired cellular energy metabolism may underlie gastrointestinal motility disorders in cyclic vomiting syndrome, gastroesophageal reflux, gastric stasis, chronic diarrhea, constipation, intestinal pseudoobstruction, malabsorption syndrome, irritable bowel syndrome, as well as diseases of the liver and pancreas.

  17. Quantum manifestations of Nekhoroshev stability

    Energy Technology Data Exchange (ETDEWEB)

    Fontanari, Daniele, E-mail: fontanari@purple.univ-littoral.fr [Département de physique, Université du Littoral – Côte d' Opale, 59140 Dunkerque (France); Fassò, Francesco, E-mail: fasso@math.unipd.it [Università di Padova, Dipartimento di Matematica, Via Trieste 63, Padova 35121 (Italy); Sadovskií, Dmitrií A., E-mail: sadovski@univ-littoral.fr [Département de physique, Université du Littoral – Côte d' Opale, 59140 Dunkerque (France)

    2016-09-16

    We uncover quantum manifestations of classical Nekhoroshev theory of resonant dynamics using a simple quantum system of two coupled angular momenta with conserved equal magnitudes which corresponds to a perturbed classical integrable anisochronous Hamiltonian system. - Highlights: • Basic quantum manifestations of classical Nekhoroshev theory are studied. • A simple anisochronous convex system with two degrees of freedom is proposed. • Zones are uncovered in the joint expectation value spectrum of quantized actions. • The width of the zones is given by the Nekhoroshev resonant normal forms.

  18. An overview of chemosynthetic symbioses in bivalves from the North Atlantic and Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    S. Duperron

    2013-05-01

    Full Text Available Deep-sea bivalves found at hydrothermal vents, cold seeps and organic falls are sustained by chemosynthetic bacteria that ensure part or all of their carbon nutrition. These symbioses are of prime importance for the functioning of the ecosystems. Similar symbioses occur in other bivalve species living in shallow and coastal reduced habitats worldwide. In recent years, several deep-sea species have been investigated from continental margins around Europe, West Africa, eastern Americas, the Gulf of Mexico, and from hydrothermal vents on the Mid-Atlantic Ridge. In parallel, numerous, more easily accessible shallow marine species have been studied. Herein we provide a summary of the current knowledge available on chemosymbiotic bivalves in the area ranging west-to-east from the Gulf of Mexico to the Sea of Marmara, and north-to-south from the Arctic to the Gulf of Guinea. Characteristics of symbioses in 53 species from the area are summarized for each of the five bivalve families documented to harbor chemosynthetic symbionts (Mytilidae, Vesicomyidae, Solemyidae, Thyasiridae and Lucinidae. Comparisons are made between the families, with special emphasis on ecology, life cycle, and connectivity. Chemosynthetic symbioses are a major adaptation to ecosystems and habitats exposed to reducing conditions. However, relatively little is known regarding their diversity and functioning, apart from a few "model species" on which effort has focused over the last 30 yr. In the context of increasing concern about biodiversity and ecosystems, and increasing anthropogenic pressure on oceans, we advocate a better assessment of the diversity of bivalve symbioses in order to evaluate the capacities of these remarkable ecological and evolutionary units to withstand environmental change.

  19. An overview of chemosynthetic symbioses in bivalves from the North Atlantic and Mediterranean Sea

    Science.gov (United States)

    Duperron, S.; Gaudron, S. M.; Rodrigues, C. F.; Cunha, M. R.; Decker, C.; Olu, K.

    2013-05-01

    Deep-sea bivalves found at hydrothermal vents, cold seeps and organic falls are sustained by chemosynthetic bacteria that ensure part or all of their carbon nutrition. These symbioses are of prime importance for the functioning of the ecosystems. Similar symbioses occur in other bivalve species living in shallow and coastal reduced habitats worldwide. In recent years, several deep-sea species have been investigated from continental margins around Europe, West Africa, eastern Americas, the Gulf of Mexico, and from hydrothermal vents on the Mid-Atlantic Ridge. In parallel, numerous, more easily accessible shallow marine species have been studied. Herein we provide a summary of the current knowledge available on chemosymbiotic bivalves in the area ranging west-to-east from the Gulf of Mexico to the Sea of Marmara, and north-to-south from the Arctic to the Gulf of Guinea. Characteristics of symbioses in 53 species from the area are summarized for each of the five bivalve families documented to harbor chemosynthetic symbionts (Mytilidae, Vesicomyidae, Solemyidae, Thyasiridae and Lucinidae). Comparisons are made between the families, with special emphasis on ecology, life cycle, and connectivity. Chemosynthetic symbioses are a major adaptation to ecosystems and habitats exposed to reducing conditions. However, relatively little is known regarding their diversity and functioning, apart from a few "model species" on which effort has focused over the last 30 yr. In the context of increasing concern about biodiversity and ecosystems, and increasing anthropogenic pressure on oceans, we advocate a better assessment of the diversity of bivalve symbioses in order to evaluate the capacities of these remarkable ecological and evolutionary units to withstand environmental change.

  20. First records of Freshwater Bivalves of Ilha Grande National Park, Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Flávio Henrique Ragonha

    2014-03-01

    Full Text Available The Ilha Grande National Park, Paraná, Brazil, is located in the Upper Paraná River and has characteristics typical of a floodplains. This protected area includes lagoons connected and disconnected to the Paraná River, although the latter also connect during periods of high water level, thus composing a heterogeneous group of lacustrine environments. The enormous potential the flora and fauna diversities are still little known to the region, as can be seen through benthic invertebrates, inclunding bivalves mollusks. The granulometric composition of these floodplain lagoons was formed mainly by mud and very fine sand. Furthermore, organic matter composition was predominantly of fine particulate. The other abiotic factors differed from lagoons located within the island of the park to those located in the left margin of Paraná River. The results demonstrated the importance of abiotic factors such as the physical composition of granulometric texture, organic matter and macrophyte banks, to the establishment of bivalves in these floodplain lagoons. We recorded bivalves of Pisidium (native, Diplodon (native, and Corbicula (invasive. The highest values of Diplodon sp. density were observed at São João/C lake, for Pisidium sterkianum (Pilsbry, 1897 at São João/M lake, and to Jatobá/C lagoon with high density of invasive species Corbicula fluminea (Müller, 1774. This study to obtain conduct the first records of freshwater bivalves in floodplains lagoon in the Ilha Grande National Park, and provides contributions to better understanding the ecology of these mollusks. The recording of native species in the region of Upper Paraná River floodplain after a lomg period without new records, demonstrated the importance of protecting the lagoons of the Ilha Grande National Park as they can be a possible refuge to some species of native freshwater bivalves.

  1. The use of bivalves as rapid, real-time indicators of aquatic pollution

    International Nuclear Information System (INIS)

    Markich, S.J.

    1995-01-01

    The ability of bivalves to filter large volumes of water on a daily basis, combined with the relatively high permeability of their cell membranes, make them valuable organisms to use in the contemporary detection of pollution. Bivalves are well known to respond to chemical contaminants by isolating their soft tissues from the aquatic medium by valve closure. The sensory acuity (via specialized sensory regions including the osphradium) and associated repertoire of this behavioral response can be employed to assess subtle effects exerted by chemical contaminants, such as complex effluents, that may ultimately influence the survival of these organisms. As hazard assessment tools, behavioral studies reflect sublethal toxicity and often yield a highly sensitive estimate of the lowest observable effect concentration (LOEC). Moreover, valve movement behavior has been identified as one of the more sensitive biological early warning measures to a variety of aquatic contaminants, in comparison with those used in other aquatic animal phyla. Therefore, the valve movement behavior of both freshwater (Hyridella depressa, Velesunio angasi and V. ambiguus) and marine (Mytilus edulis) bivalves was continuously monitored, using an on-line computer based data acquisition system, during exposure to either trace metals (e.g. Cu, Cd, Mn and U) or complex effluents (ie treated sewage effluent and acid leachate derived from contaminated Sydney Harbour sediments), in the context of using the valve movement behavior of the bivalve species to indicate the biological significance of exposure to the above-mentioned pollutants. The results indicate that several components of the valve movement behavior of each bivalve provide quantifiable and ecologically interpretable sub-lethal endpoints for the rapid and sensitive evaluation of waters containing either complex effluents or elevated levels of trace metals

  2. Severe pulmonary manifestation of leptospirosis

    NARCIS (Netherlands)

    Helmerhorst, H. J. F.; van Tol, E. N.; Tuinman, P. R.; de Vries, P. J.; Hartskeerl, R. A.; Grobusch, M. P.; Hovius, J. W.

    2012-01-01

    Based on increasing incidence and the occurrence of worldwide outbreaks, leptospirosis is recognised as an emerging zoonosis. Severe manifestations are associated with high morbidity and mortality rates and may therefore pose an important risk to public health, especially in certain high prevalence

  3. Mucocutaneous manifestations of Cowden's syndrome

    Directory of Open Access Journals (Sweden)

    Kundoor Vinay Kumar Reddy

    2016-01-01

    Full Text Available Cowden's syndrome is an autosomal dominant genodermatosis with variable orofacial and systemic manifestations. Here we present one such classical case of Cowden's syndrome in a 45-year-old female patient with features such as multiple cutaneous papillomatosis, oral fibromas, and fibromas involving multiple organs such as gastrointestinal tract (multiple polyps, thyroid disorders, and breast cancer.

  4. OCULAR MANIFESTATIONS OF HEAD INJURIES

    Directory of Open Access Journals (Sweden)

    Kanukollu Venkata Madusudana Rao

    2016-12-01

    Full Text Available BACKGROUND This prospective study aimed to evaluate the incidence of ocular manifestations in head injury and their correlation with the intracranial lesions. MATERIALS AND METHODS A total of 108 consecutive cases of closed head injury admitted in the neurosurgical ward of a tertiary teaching hospital underwent a thorough ophthalmic assessment. Clinical examination, radiological imaging and Glasgow Coma Scale (GCS were applied to grade the severity of injury. RESULTS Total number of 108 patients of head injury were examined of which 38 patients had ocular manifestations (35.18%. Of these, 85.18% were males, 84% of injuries were due to road traffic accidents and 16% were due to fall from a height. The ocular manifestations were as follows- Orbital complications were seen in 6 patients (15.8%. Anterior segment manifestations included black eyes seen in 10 patients (26.3%, subconjunctival haemorrhage in 10.5% of patients (4 patients, corneal involvement in 21% of patients (8 patients and pupillary involvement in 50% of patients (19 patients. Posterior segment manifestations were seen in 26.3% of patients (10 patients and were as follows- Purtscher’s retinopathy in 2 patients and optic atrophy in 5 patients. Cranial nerve palsies were seen in 15 patients (39.47% and supranuclear movement disorders were seen in 3 patients (8%. CONCLUSION Even though, neurosurgeons perform comprehensive clinical examination including eye examination, the main purpose is limited to aid topical diagnosis of neurological lesions. This study emphasises the importance of a detailed eye examination by an ophthalmologist to prevent irreversible visual loss in addition to aiding in the neurological diagnosis. Pupillary involvement, papilloedema and ocular motor paresis pointed to a more severe head injury. This observational prospective study helped us to correlate the severity of head injuries in association with ocular findings in patients admitted in neurosurgical ward

  5. Severe pulmonary manifestation of leptospirosis.

    Science.gov (United States)

    Helmerhorst, H J F; van Tol, E N; Tuinman, P R; de Vries, P J; Hartskeerl, R A; Grobusch, M P; Hovius, J W

    2012-06-01

    Based on increasing incidence and the occurrence of worldwide outbreaks, leptospirosis is recognised as an emerging zoonosis. Severe manifestations are associated with high morbidity and mortality rates and may therefore pose an important risk to public health, especially in certain high prevalence areas. A considerable number of infections progress to a severe form, which can present as the well-known triad of jaundice, impaired renal function and haemorrhage, known as Weil's disease. The severe pulmonary form of leptospirosis (SPFL) is a less known entity and is characterised by intra-alveolar haemorrhage and can lead to acute respiratory failure and death when adequate treatment fails. Prognostic factors correlating with severity and survival of leptospirosis include indicators of renal failure, pulmonary involvement and electrolyte imbalances. We report an imported case of SPFL in a returning traveller, and review the literature discussing epidemiology, clinical manifestations, prognostic factors and treatment of this resurgent disease.

  6. Unusual clinical manifestations of leptospirosis

    Directory of Open Access Journals (Sweden)

    Bal A

    2005-01-01

    Full Text Available Leptospirosis has protean clinical manifestations. The classical presentation of the disease is an acute biphasic febrile illness with or without jaundice. Unusual clinical manifestations may result from involvement of pulmonary, cardiovascular, neural, gastrointestinal, ocular and other systems. Immunological phenomena secondary to antigenic mimicry may also be an important component of many clinical features and may be responsible for reactive arthritis. Leptospirosis in early pregnancy may lead to fetal loss. There are a few reports of leptospirosis in HIV- infected individuals but no generalisation can be made due to paucity of data. It is important to bear in mind that leptospiral illness may be a significant component in cases of dual infections or in simultaneous infections with more than two pathogens.

  7. Otolaryngic manifestations of Cushing disease.

    Science.gov (United States)

    Kuan, Edward C; Peng, Kevin A; Suh, Jeffrey D; Bergsneider, Marvin; Wang, Marilene B

    2017-08-01

    Cushing disease is a relatively rare cause of Cushing syndrome secondary to a hyperfunctioning pituitary adenoma. In addition to signs and symptoms of hypercortisolism, Cushing disease may present with diverse otolaryngic manifestations, which may guide diagnosis and management. We performed a retrospective chart review of patients who were found to have Cushing disease and who underwent transnasal transsphenoidal surgery for pituitary adenomas between January 1, 2007, and July 1, 2014, at a tertiary academic medical center. There were 37 consecutive patients in this series with Cushing disease caused by a pituitary adenoma. Fifteen (41%) patients complained of visual changes. Five (14%) patients suffered from obstructive sleep apnea. Four (11%) patients had thyroid disease. Other symptoms included hearing loss, vertigo, tinnitus, epistaxis, dysphagia, and salivary gland swelling. Although Cushing disease traditionally presents with classic "Cushingoid" systemic features, it also may present with various otolaryngic manifestations. A thorough workup by otolaryngologists is critical in the comprehensive management of these patients.

  8. Cardiopulmonary Manifestations of Ankylosing Spondylitis

    Science.gov (United States)

    Momeni, Mahnaz; Taylor, Nora; Tehrani, Mahsa

    2011-01-01

    Ankylosing spondylitis is a chronic inflammatory condition that usually affects young men. Cardiac dysfunction and pulmonary disease are well-known and commonly reported extra-articular manifestation, associated with ankylosing spondylitis (AS). AS has also been reported to be specifically associated with aortitis, aortic valve diseases, conduction disturbances, cardiomyopathy and ischemic heart disease. The pulmonary manifestations of the disease include fibrosis of the upper lobes, interstitial lung disease, ventilatory impairment due to chest wall restriction, sleep apnea, and spontaneous pneumothorax. They are many reports detailing pathophysiology, hypothesized mechanisms leading to these derangements, and estimated prevalence of such findings in the AS populations. At this time, there are no clear guidelines regarding a stepwise approach to screen these patients for cardiovascular and pulmonary complications. PMID:21547038

  9. Sensitivity of Mediterranean bivalve mollusc aquaculture to climate change, ocean acidification, and other environmental pressures: findings from a producers’ survey

    NARCIS (Netherlands)

    Rodrigues, L.; van den Bergh, J.C.J.M.; Mass, F.; Theodorou, J.A.; Ziveri, P.; Gazeau, F.

    2015-01-01

    Human-induced climate change and ocean acidification are global environmental phenomena with a common driver: anthropogenic emissions of carbon dioxide. Both processes potentially threaten the Mediterranean bivalve mollusc aquaculture sector, which is economically relevant to several regions and

  10. Skin manifestations of child abuse

    OpenAIRE

    Ermertcan Aylin; Ertan Pelin

    2010-01-01

    Child abuse is a major public health problem all over the world. There are four major types of abuse: physical abuse, sexual abuse, emotional abuse and neglect. The most common manifestations of child abuse are cutaneous and their recognition; and differential diagnosis is of great importance. Clinicians, especially dermatologists, should be alert about the skin lesions of child abuse. In the diagnosis and management of child abuse, a multidisciplinary approach with ethical and legal procedur...

  11. Atypical Neurological Manifestations Of Hypokalemia

    Directory of Open Access Journals (Sweden)

    pal P K

    2004-01-01

    Full Text Available A part from the well-established syndrome of motor paralysis, hypokalemia may present with atypical neurological manifestations, which are not well documented in literature. Methods: We treated 30 patients of hypokalemia whose neurological manifestations improved after corrections of hypokalemia. A retrospective chart review of the clinical profile was done with emphasis on the evolution of symptoms and occurrence of unusual manifestations. Results: Twenty-eight patients had subacute quadriparesis with duration of symptoms varying from 10hrs to 7 days and two had slowly progressive quadriparesis. Fifty percent of patients had more than one attack of paralysis. Early asymmetric weakness (11, stiffness and abnormal posture of hands (7, predominant bibrachial weakness (4, distal paresthesias (4, hemiparesthesia (1, hyperreflexia(4, early severe weakness of neck muscles (3, chorea (1, trismus (1,and, retention of urine (1 were the unusual features observed. The means level of serum potassium on admission was 2.1+0.6mEq/L.and the serum creatine kinase was elevated in 14 out of 17 patients. All patients except two had complete recovery.

  12. Gastrointestinal manifestations in APECED syndrome.

    Science.gov (United States)

    Kluger, Nicolas; Jokinen, Martta; Krohn, Kai; Ranki, Annamari

    2013-02-01

    Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) (or autoimmune polyendocrine syndrome type 1) is a rare autosomal recessive disorder caused by mutations in the autoimmune regulator gene. It causes a loss in central immune tolerance, failure to eliminate autoreactive T cells in the thymus, and their escape to the periphery. APECED patients are susceptible to mucocutaneous candidiasis and multiple endocrine and nonendocrine autoimmune diseases. Although it depends on the series, approximately 25% of APECED patients are affected by gastrointestinal (GI) manifestations, mainly autoimmune-related disorders like autoimmune hepatitis, atrophic gastritis with or without pernicious anemia (Biermer disease), intestinal infections, and malabsorption. In contrast to the major organ-specific autoimmune symptoms of APECED, the GI symptoms and their underlying pathogenesis are poorly understood. Yet isolated case reports and small series depict severe intestinal involvement in children, leading to malabsorption, multiple deficiencies, growth impairment, and possible death. Moreover, very few systematic studies of GI function with intestinal biopsies have been performed. GI symptoms may be the first manifestation of APECED, yet they may have various causes; effective treatment will therefore vary. We provide here an updated review of GI manifestations in APECED, including principles of diagnosis and therapy.

  13. Trophic Dynamics of Filter Feeding Bivalves in the Yangtze Estuarine Intertidal Marsh: Stable Isotope and Fatty Acid Analyses.

    Directory of Open Access Journals (Sweden)

    Sikai Wang

    Full Text Available Benthic bivalves are important links between primary production and consumers, and are essential intermediates in the flow of energy through estuarine systems. However, information on the diet of filter feeding bivalves in estuarine ecosystems is uncertain, as estuarine waters contain particulate matter from a range of sources and as bivalves are opportunistic feeders. We surveyed bivalves at different distances from the creek mouth at the Yangtze estuarine marsh in winter and summer, and analyzed trophic dynamics using stable isotope (SI and fatty acid (FA techniques. Different bivalve species had different spatial distributions in the estuary. Glauconome chinensis mainly occurred in marshes near the creek mouth, while Sinonovacula constricta preferred the creek. Differences were found in the diets of different species. S. constricta consumed more diatoms and bacteria than G. chinensis, while G. chinensis assimilated more macrophyte material. FA markers showed that plants contributed the most (38.86 ± 4.25% to particular organic matter (POM in summer, while diatoms contributed the most (12.68 ± 1.17% during winter. Diatoms made the largest contribution to the diet of S. constricta in both summer (24.73 ± 0.44% and winter (25.51 ± 0.59%, and plants contributed no more than 4%. This inconsistency indicates seasonal changes in food availability and the active feeding habits of the bivalve. Similar FA profiles for S. constricta indicated that the bivalve had a similar diet composition at different sites, while different δ13C results suggested the diet was derived from different carbon sources (C4 plant Spartina alterniflora and C3 plant Phragmites australis and Scirpus mariqueter at different sites. Species-specific and temporal and/or spatial variability in bivalve feeding may affect their ecological functions in intertidal marshes, which should be considered in the study of food webs and material flows in estuarine ecosystems.

  14. Trophic Dynamics of Filter Feeding Bivalves in the Yangtze Estuarine Intertidal Marsh: Stable Isotope and Fatty Acid Analyses.

    Science.gov (United States)

    Wang, Sikai; Jin, Binsong; Qin, Haiming; Sheng, Qiang; Wu, Jihua

    2015-01-01

    Benthic bivalves are important links between primary production and consumers, and are essential intermediates in the flow of energy through estuarine systems. However, information on the diet of filter feeding bivalves in estuarine ecosystems is uncertain, as estuarine waters contain particulate matter from a range of sources and as bivalves are opportunistic feeders. We surveyed bivalves at different distances from the creek mouth at the Yangtze estuarine marsh in winter and summer, and analyzed trophic dynamics using stable isotope (SI) and fatty acid (FA) techniques. Different bivalve species had different spatial distributions in the estuary. Glauconome chinensis mainly occurred in marshes near the creek mouth, while Sinonovacula constricta preferred the creek. Differences were found in the diets of different species. S. constricta consumed more diatoms and bacteria than G. chinensis, while G. chinensis assimilated more macrophyte material. FA markers showed that plants contributed the most (38.86 ± 4.25%) to particular organic matter (POM) in summer, while diatoms contributed the most (12.68 ± 1.17%) during winter. Diatoms made the largest contribution to the diet of S. constricta in both summer (24.73 ± 0.44%) and winter (25.51 ± 0.59%), and plants contributed no more than 4%. This inconsistency indicates seasonal changes in food availability and the active feeding habits of the bivalve. Similar FA profiles for S. constricta indicated that the bivalve had a similar diet composition at different sites, while different δ13C results suggested the diet was derived from different carbon sources (C4 plant Spartina alterniflora and C3 plant Phragmites australis and Scirpus mariqueter) at different sites. Species-specific and temporal and/or spatial variability in bivalve feeding may affect their ecological functions in intertidal marshes, which should be considered in the study of food webs and material flows in estuarine ecosystems.

  15. Bivalved Versus Circumferential Cast Immobilization for Displaced Forearm Fractures: A Randomized Clinical Trial to Assess Efficacy and Safety.

    Science.gov (United States)

    Bae, Donald S; Valim, Clarissa; Connell, Patricia; Brustowicz, Katherine A; Waters, Peter M

    2017-06-01

    The purpose of this study was to determine the effects of bivalved versus circumferential cast immobilization on maintenance of reduction and associated complications after closed reduction (CR) of radius and/or ulna fractures in children. Two hundred two children with displaced radius and/or ulna fractures were randomized to either circumferential (n=101) or bivalved (n=101) long-arm casts after CR. The mean age was 10±3 years. There were no significant differences between groups in terms of age, sex, or initial fracture displacement or angulation. Clinical and radiographic evaluations were performed at 1, 2, 4, and 6 weeks postreduction. Radiographic loss of reduction (LOR), need for remanipulation or surgery, and associated complications of compartment syndrome, cast saw injury, and neurovascular compromise were recorded. Overall, the median angulation of the radius and ulna fractures improved from 20 and 18 degrees to 3 and 2 degrees after CR, respectively. The median cast index after reduction was 0.78 in the bivalved group and 0.80 in the circumferential group. The median angulation of the radius and ulna was 8 and 1 degrees at 4 weeks, with no significant difference between groups. By the fourth week of follow-up, 70 patients (34%)-35 bivalved and 35 circumferential-had radiographic LOR. Forty-seven patients (23%)-23 bivalved and 24 circumferential-underwent remanipulation or surgical reduction and fixation. There were no significant differences between groups with respect to LOR rate or need for surgical treatment. One bivalved patient sustained a cast saw injury, and 3 bivalved patients had transient neurological abnormalities. No patients developed compartment syndrome. Cast immobilization is effective in the majority of patients after CR of displaced forearm fractures. There were no significant differences in maintenance of reduction, need for surgery, or complications between bivalved or circumferential long-arm casts. Level I-therapeutic.

  16. Thoracic manifestation of tuberculosis; Thorakale Manifestation der Tuberkulose

    Energy Technology Data Exchange (ETDEWEB)

    Kienzl-Palma, D.; Prosch, H. [Medizinische Universitaet Wien, Abteilung fuer Allgemeine Radiologie und Kinderradiologie, Universitaetsklinik fuer Radiologie und Nuklearmedizin, Wien (Austria)

    2016-10-15

    Tuberculosis (TB) is a granulomatous disease caused by Mycobacterium tuberculosis and transmission is via an airborne route by droplet infection. In the majority of cases patients have thoracic TB, which most frequently presents with hilar lymphadenopathy and pulmonary manifestation. Due to the rise in incidence of TB in central Europe to be expected over the coming years, it is essential to be acquainted with the radiological manifestations of pulmonary TB, particularly to be able to discriminate active from inactive TB. Due to the use of molecular techniques entailing DNA fingerprinting, the traditional classification of TB in primary and postprimary TB is being challenged. These genetic studies have revealed that variations in the clinical and radiographic appearance of TB are mainly affected by the immune status of the patients. Due to the low prevalence of TB in central Europe and the wide variation of radiological presentations, the diagnosis and therapy of TB is often delayed. In this article, the radiographic manifestations of thoracic TB are summarized and discussed. Together with the medical history and bacteriological tests, chest X-ray imaging and computed tomography (CT) play a major role not only in the detection of TB but also in the follow-up during and after therapy. Chest X-radiographs should be the primary diagnostic method in patients with suspected TB in screening as well as for diagnosis and therapy monitoring. The use of CT is more sensitive than chest radiographs and is frequently performed after chest radiographs to obtain detailed information about subtle parenchymal changes or lymph node manifestation. When active TB is suspected CT should be performed. Tree in bud, lobular consolidations, centrilobular nodules, cavities and ground-glass opacification are typical changes in active TB. (orig.) [German] Tuberkulose (Tbc) ist eine durch Troepfchen uebertragene granulomatoese Infektionserkrankung, die durch das Mycobacterium tuberculosis

  17. [Neuropsychiatric manifestations ushering pernicious anemia].

    Science.gov (United States)

    Mrabet, S; Ellouze, F; Ellini, S; Mrad, M F

    2015-12-01

    Biermer disease or pernicious anemia is an autoimmune atrophic gastritis characterized by the lack of secretion of gastric intrinsic factor. This leads to an insufficient absorption of vitamin B12 in the ileum. Clinical manifestations are mainly hematologic. Neuropsychiatric manifestations are known but are less frequent especially early in the disease. Inaugural neuropsychiatric arrays are rare and various thus making diagnosis difficult. In this article, we report through two clinical cases different neuropsychiatric manifestations revealing pernicious anemia. Mrs. C.O., aged 56, presented after surgery for gallstones, an acute psychiatric array associated with gait disorders. She had no history of neurological or psychiatric problems. The psychiatric interview revealed delirious syndrome, depressive symptoms and anxiety. Neurological examination noted a flaccid paraplegia with peripheral neuropathic syndrome and myoclonus in the upper limbs. At the full blood count, a macrocytosis (VGM: 112.2fl) without anemia was found. The level of vitamin B12 in the blood was low. Cerebro-spinal MRI was suggestive of a neuro-Biermer and showed hyper signal in the cervical cord on T2-weighted sagittal section. In axial section, hyper signal appears at the posterior columns in the form of V. There were no brain abnormalities. A sensorimotor axonal polyneuropathy was diagnosed. The patient received vitamin B12 intramuscularly for ten days associated with neuroleptic treatment. Mrs. R.M., aged 40, was brought to the psychiatry consultation for acute behavioral disorders progressively worsening over a month. An anxiety syndrome, depressive syndrome and delirious syndrome were identified. Neurological examination showed a posterior cordonal syndrome with quadripyramidal syndrome. Full blood count showed a macrocytic anemia. Serum B12 level was collapsed. Cerebro-spinal MRI was normal. She received vitamin B12 with clinical and biological improvement. Features of pernicious anemia

  18. The known and unknown sources of reactive oxygen and nitrogen species in haemocytes of marine bivalve molluscs.

    Science.gov (United States)

    Donaghy, Ludovic; Hong, Hyun-Ki; Jauzein, Cécile; Choi, Kwang-Sik

    2015-01-01

    Reactive oxygen and nitrogen species (ROS and RNS) are naturally produced in all cells and organisms. Modifications of standard conditions alter reactive species generation and may result in oxidative stress. Because of the degradation of marine ecosystems, massive aquaculture productions, global change and pathogenic infections, oxidative stress is highly prevalent in marine bivalve molluscs. Haemocytes of bivalve molluscs produce ROS and RNS as part of their basal metabolism as well as in response to endogenous and exogenous stimuli. However, sources and pathways of reactive species production are currently poorly deciphered in marine bivalves, potentially leading to misinterpretations. Although sources and pathways of ROS and RNS productions are highly conserved between vertebrates and invertebrates, some uncommon pathways seem to only exist in marine bivalves. To understand the biology and pathobiology of ROS and RNS in haemocytes of marine bivalves, it is necessary to characterise their sources and pathways of production. The aims of the present review are to discuss the currently known and unknown intracellular sources of reactive oxygen and nitrogen species in marine bivalve molluscs, in light of terrestrial vertebrates, and to expose principal pitfalls usually encountered. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Proteomic profiling of cytosolic glutathione transferases from three bivalve species: Corbicula fluminea, Mytilus galloprovincialis and Anodonta cygnea.

    Science.gov (United States)

    Martins, José Carlos; Campos, Alexandre; Osório, Hugo; da Fonseca, Rute; Vasconcelos, Vítor

    2014-01-27

    Suspension-feeding bivalves are considered efficient toxin vectors with a relative insensitivity to toxicants compared to other aquatic organisms. This fact highlights the potential role of detoxification enzymes, such as glutathione transferases (GSTs), in this bivalve resistance. Nevertheless, the GST system has not been extensively described in these organisms. In the present study, cytosolic GSTs isoforms (cGST) were surveyed in three bivalves with different habitats and life strategies: Corbicula fluminea, Anodonta cygnea and Mytilus galloprovincialis. GSTs were purified by glutathione-agarose affinity chromatography, and the collection of expressed cGST classes of each bivalve were identified using a proteomic approach. All the purified extracts were also characterized kinetically. Results reveal variations in cGST subunits collection (diversity and properties) between the three tested bivalves. Using proteomics, four pi-class and two sigma-class GST subunits were identified in M. galloprovincialis. C. fluminea also yielded four pi-class and one sigma-class GST subunits. For A. cygnea, two mu-class and one pi-class GST subunits were identified, these being the first record of GSTs from these freshwater mussels. The affinity purified extracts also show differences regarding enzymatic behavior among species. The variations found in cGST collection and kinetics might justify diverse selective advantages for each bivalve organism.

  20. Proteomic Profiling of Cytosolic Glutathione Transferases from Three Bivalve Species: Corbicula fluminea, Mytilus galloprovincialis and Anodonta cygnea

    Directory of Open Access Journals (Sweden)

    José Carlos Martins

    2014-01-01

    Full Text Available Suspension-feeding bivalves are considered efficient toxin vectors with a relative insensitivity to toxicants compared to other aquatic organisms. This fact highlights the potential role of detoxification enzymes, such as glutathione transferases (GSTs, in this bivalve resistance. Nevertheless, the GST system has not been extensively described in these organisms. In the present study, cytosolic GSTs isoforms (cGST were surveyed in three bivalves with different habitats and life strategies: Corbicula fluminea, Anodonta cygnea and Mytilus galloprovincialis. GSTs were purified by glutathione-agarose affinity chromatography, and the collection of expressed cGST classes of each bivalve were identified using a proteomic approach. All the purified extracts were also characterized kinetically. Results reveal variations in cGST subunits collection (diversity and properties between the three tested bivalves. Using proteomics, four pi-class and two sigma-class GST subunits were identified in M. galloprovincialis. C. fluminea also yielded four pi-class and one sigma-class GST subunits. For A. cygnea, two mu-class and one pi-class GST subunits were identified, these being the first record of GSTs from these freshwater mussels. The affinity purified extracts also show differences regarding enzymatic behavior among species. The variations found in cGST collection and kinetics might justify diverse selective advantages for each bivalve organism.

  1. New Insights into Pathogenic Vibrios Affecting Bivalves in Hatcheries: Present and Future Prospects

    Directory of Open Access Journals (Sweden)

    Javier Dubert

    2017-05-01

    Full Text Available Hatcheries constitute nowadays the only viable solution to support the husbandry of bivalve molluscs due to the depletion and/or overexploitation of their natural beds. Hatchery activities include the broodstock conditioning and spawning, rearing larvae and spat, and the production of microalgae to feed all stages of the production cycle. However, outbreaks of disease continue to be the main bottleneck for successful larval and spat production, most of them caused by different representatives of the genus Vibrio. Therefore, attention must be paid on preventive and management measures that allow the control of such undesirable bacterial populations. The present review provides an updated picture of the recently characterized Vibrio species associated with disease of bivalve molluscs during early stages of development, including the controversial taxonomic affiliation of some of them and relevant advances in the knowledge of their virulence determinants. The problematic use of antibiotics, as well as its eco-friendly alternatives are also critically discussed.

  2. An ecosystem-based approach and management framework for the integrated evaluation of bivalve aquaculture impacts

    DEFF Research Database (Denmark)

    Cranford, Peter J.; Kamermans, Pauline; Krause, Gesche

    2012-01-01

    -Impact-Response (DPSIR) management framework incorporates the connectivity between human and ecological issues and would permit available performance indicators to be identified and organized in a manner that facilitates different regulatory needs. Suitable performance indicators and modeling approaches, which are used...... to assess DPSIR framework components, are reviewed with a focus on the key environmental issues associated with bivalve farming. Indicator selection criteria are provided to facilitate constraining the number of indicators within the management framework. It is recommended that an ecosystem-based approach......An ecosystem-based approach to bivalve aquaculture management is a strategy for the integration of aquaculture within the wider ecosystem, including human aspects, in such a way that it promotes sustainable development, equity, and resilience of ecosystems. Given the linkage between social...

  3. Metals and organotins in multiple bivalve species in a one-off global survey

    DEFF Research Database (Denmark)

    Larsen, Martin Mørk; Strand, Jakob; Christensen, Jan H.

    2011-01-01

    concentrations (BACs) agreed in the Oslo-Paris convention (OSPAR) for the North Sea, and at most harbours the concentrations were orders of magnitude above BACs. The lowest concentrations of Cd and Pb measured here suggest that the BACs should be lower in a worldwide context. The sources of metals were......The Galathea 3 expedition circumnavigated the globe in 2006-2007 and collected marine samples from six continents. Bivalves were collected from harbours, other impacted locations and reference sites, and samples from 57 sites were analyzed for metals and 47 for organotins, to assess current...... contamination levels on a global scale. Metal concentrations in nine bivalve species were normalised to the Mytilidae family using conversion factors based on cosampled species and literature bioconcentration factors. The lowest metal and tributyltin concentrations were below background assessment...

  4. Ocean acidification increases cadmium accumulation in marine bivalves: a potential threat to seafood safety.

    Science.gov (United States)

    Shi, Wei; Zhao, Xinguo; Han, Yu; Che, Zhumei; Chai, Xueliang; Liu, Guangxu

    2016-01-21

    To date, the effects of ocean acidification on toxic metals accumulation and the underlying molecular mechanism remains unknown in marine bivalve species. In the present study, the effects of the realistic future ocean pCO2 levels on the cadmium (Cd) accumulation in the gills, mantle and adductor muscles of three bivalve species, Mytilus edulis, Tegillarca granosa, and Meretrix meretrix, were investigated. The results obtained suggested that all species tested accumulated significantly higher Cd (p ocean acidification-induced increase in Cd accumulation may have occurred due to (i) the ocean acidification increased the concentration of Cd and the Cd(2+)/Ca(2+) in the seawater, which in turn increased the Cd influx through Ca channel; (ii) the acidified seawater may have brought about epithelia damage, resulting in easier Cd penetration; and (iii) ocean acidification hampered Cd exclusion.

  5. Prevalence of hepatitis A virus in bivalve molluscs sold in Granada (Spain) fish markets.

    Science.gov (United States)

    Moreno Roldán, Elena; Espigares Rodríguez, Elena; Espigares García, Miguel; Fernández-Crehuet Navajas, Milagros

    2013-06-01

    Viruses are the leading cause of foodborne illness associated with the consumption of raw or slightly cooked contaminated shellfish. The aim of this study was to evaluate the prevalence of hepatitis A virus in molluscs. Standard and real-time reverse transcription-polymerase chain reaction procedures were used to monitor bivalve molluscs from the Granada fish markets (southern Spain) for this human enteric virus. Between February 2009 and October 2010, we collected a total of 329 samples of different types of bivalve molluscs (mussels, smooth clams, striped venus, and grooved clams). The results showed the presence of hepatitis A virus in 8.5% of the 329 samples analyzed. We can therefore confirm that conventional fecal indicators are unreliable for demonstrating the presence or absence of viruses. The presence of hepatitis A virus in molluscs destined for human consumption is a potential health risk in southern Spain.

  6. Morphological diversity of microstructures occurring in selected recent bivalve shells and their ecological implications

    Directory of Open Access Journals (Sweden)

    Brom Krzysztof Roman

    2016-12-01

    Full Text Available Environmental adaptation of molluscs during evolution has led to form biomineral exoskeleton – shell. The main compound of their shells is calcium carbonate, which is represented by calcite and/or aragonite. The mineral part, together with the biopolymer matrix, forms many types of microstructures, which are differ in texture. Different types of internal shell microstructures are characteristic for some bivalve groups. Studied bivalve species (freshwater species – duck mussel (Anodonta anatina Linnaeus, 1758 and marine species – common cockle (Cerastoderma edule Linnaeus, 1758, lyrate Asiatic hard clam (Meretrix lyrata Sowerby II, 1851 and blue mussel (Mytilus edulis Linnaeus, 1758 from different locations and environmental conditions, show that the internal shell microstructure with the shell morphology and thickness have critical impact to the ability to survive in changing environment and also to the probability of surviving predator attack. Moreover, more detailed studies on molluscan structures might be responsible for create mechanically resistant nanomaterials.

  7. Semi-automatic surface sediment sampling system - A prototype to be implemented in bivalve fishing surveys

    Science.gov (United States)

    Rufino, Marta M.; Baptista, Paulo; Pereira, Fábio; Gaspar, Miguel B.

    2018-01-01

    In the current work we propose a new method to sample surface sediment during bivalve fishing surveys. Fishing institutes all around the word carry out regular surveys with the aim of monitoring the stocks of commercial species. These surveys comprise often more than one hundred of sampling stations and cover large geographical areas. Although superficial sediment grain sizes are among the main drivers of benthic communities and provide crucial information for studies on coastal dynamics, overall there is a strong lack of this type of data, possibly, because traditional surface sediment sampling methods use grabs, that require considerable time and effort to be carried out on regular basis or on large areas. In face of these aspects, we developed an easy and un-expensive method to sample superficial sediments, during bivalve fisheries monitoring surveys, without increasing survey time or human resources. The method was successfully evaluated and validated during a typical bivalve survey carried out on the Northwest coast of Portugal, confirming that it had any interference with the survey objectives. Furthermore, the method was validated by collecting samples using a traditional Van Veen grabs (traditional method), which showed a similar grain size composition to the ones collected by the new method, on the same localities. We recommend that the procedure is implemented on regular bivalve fishing surveys, together with an image analysis system to analyse the collected samples. The new method will provide substantial quantity of data on surface sediment in coastal areas, using a non-expensive and efficient manner, with a high potential application in different fields of research.

  8. Impact of seawater carbonate chemistry on the calcification of marine bivalves

    OpenAIRE

    Thomsen Jörn; Haynert Kristin; Wegner K Mathias; Melzner Frank

    2015-01-01

    Bivalve calcification, particular of the early larval stages is highly sensitive to the change of ocean carbonate chemistry resulting from atmospheric CO2 uptake. Earlier studies suggested that declining seawater [CO32−] and thereby lowered carbonate saturation affect shell production. However, disturbances of physiological processes such as acid-base regulation by adverse seawater pCO2 and pH can affect calcification in a secondary fashion. In order to determine the e...

  9. Marine Bacteria with antimicrobials capacity isolated from cultures of bivalve mollusks

    OpenAIRE

    Fabiola Pellon; Rita Orozco; Jorge León

    2014-01-01

    Microorganisms have commonly been studied as producers of antibacterial substances; yet they are also considered producers of antifungic, antiviral, antiparasitic, citotoxics and inhibitory of other forms of cellular growth substances. This paper describes the isolation, inhibitory potential and phenotipic characterization of native bacterial strains associated to bivalve mollusks such as Argopecten purpuratus “concha de abanico” and Crassostrea gigas “ostra” in cultivation systems. From ...

  10. Effect of different extraction procedures on antimicrobial activity of marine bivalves: A comparison

    Digital Repository Service at National Institute of Oceanography (India)

    Sharma, S.; Chatterji, A.; Das, P.

    Pertanika J. Trop. Agric. Sci. 32(1): 77 - 83 (2009) ISSN: 1511-3701 ©Universiti Putra Malaysia Press Received: 20 May 2008 Accepted: 8 October 2008 * Corresponding Author Effect of Different Extraction Procedures on Antimicrobial Activity of Marine... Bivalves: A Comparison Sumita Sharma 1* , Anil Chatterji 2 and Partha Das 1 1 National Institute of Oceanography, Dona Paula, Goa-403 001, India 2 Institute of Tropical Aquaculture, Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu...

  11. Identification of lysozyme activity from two edible bivalves - Perna viridis (Linnaeus) and Meretrix casta (Chemnitz)

    Digital Repository Service at National Institute of Oceanography (India)

    Sharma, S.; Tanu; Chatterji, A.

    Pertanika J. Trop. Agric. Sci. 32(1): 85 - 90 (2009) ISSN: 1511-3701 ©Universiti Putra Malaysia Press Received: 20 May 2008 Accepted: 8 October 2008 * Corresponding Author Identification of Lysozyme Activity from Two Edible Bivalves - Perna viridis... (Linnaeus) and Meretrix casta (Chemnitz) Sumita Sharma 1* , Tanu 2 and Anil Chatterji 3 1 National Institute of Oceanography, Dona Paula, Goa, India 2 Banasthali Universiti, Rajasthan 3 Institute of Tropical Aquaculture, Universiti Malaysia Terengganu...

  12. Ecology of megabenthic bivalve communities from sandy beaches on the south coast of Portugal

    Directory of Open Access Journals (Sweden)

    Marta M. Rufino

    2010-03-01

    Full Text Available Ecological aspects of 75 megabenthic bivalve species found on the south coast of Portugal (from Vila Real to Sagres were studied based on the information provided by seasonal bivalve surveys from 2000 to 2007 (8600 hauls, simultaneously using a razor shell dredge and a clam dredge. Of the 75 species identified, 36 occurred less than 30 times, and thus were considered rare in the area. The remaining 39 bivalves were analysed according to their occurrence, bathymetric distribution, geographic preferences, seasonal preferences, burying-depth, beach exposure and river mouth proximity. All species belonging to the Pharidae and Solenidae families (razor shells and most Tellinidae were significantly more frequent in the razor shell dredge (indicating deeper burying in the sediment, whilst the families Cardiidae and Donacidae were significantly more frequent in the clam dredge (indicating that these species are probably closer to the sediment surface. As for the season, most bivalve species occurred similarly in both seasons (19 sp; 49%, but a large proportion were more abundant during the autumn surveys (17 sp., 44%, whereas only three species were commoner during the spring surveys. Most species belonging to the families Cardiidae and Mactridae were commoner in the autumn surveys. The spatial distribution differed between species and cluster analysis identified four communities with greater geographic affinity. Species belonging to the family Cardiidae were preferably found in the western part (WB and the eastern part (S of the study area, whereas the families Donacidae, Mactridae and Tellinidae occurred mainly in the central area (EB and the eastern (S coastal sectors. Overall, shallower species (modal depth at 3-6 m showed greater occurrences and abundances than the deeper ones, and the depth pattern observed did not change between seasons. Donacidae and Mactridae (except Mactra glauca were represented essentially by shallow species, whereas

  13. Bioaccumulation of selected metals in bivalves (Unionidae) and Phragmites australis inhabiting a municipal water reservoir

    OpenAIRE

    Rzymski, Piotr; Niedzielski, Przemysław; Klimaszyk, Piotr; Poniedziałek, Barbara

    2014-01-01

    Urbanization can considerably affect water reservoirs by, inter alia, input, and accumulation of contaminants including metals. Located in the course of River Cybina, Maltański Reservoir (Western Poland) is an artificial shallow water body built for recreation and sport purposes which undergoes restoration treatment (drainage) every 4 years. In the present study, we demonstrate an accumulation of nine metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn) in water, sediment, three bivalve species (Anodo...

  14. Ethno-malacological knowledge of bivalve mollusks gathering in Acupe mangrove, Santo Amaro, Bahia

    Directory of Open Access Journals (Sweden)

    Francisco José Bezerra Souto

    2009-12-01

    Full Text Available The mangrove is a highly productive ecosystem that carries out important ecological functions and that historically it has been used for the subsistence and income of countless craft fishing communities. In the mangroves of Todos os Santos Bay, including those of the District of Acupe (Santo Amaro – Bahia State, the bivalve mollusks (shellfish are among the most important resources, and their gathering is known as “mariscagem”. This work aims to characterize the knowledge of the local female shellfish gatherers regarding the biology and ecology of bivalve shellfish. Semi-structured interviews were used with local shellfish women (N=54 involving ethnotaxonomy, trophic ecology, hydrodynamics, fenology and ethnocronology. Etic-emic analisys of the data was chosen in order to compare the information obtained in the field to that from the academic literature. The results demonstrated that the shellfish women of Acupe have a significant knowledge of bivalve shellfish, in addition to aspects related to the dynamics of local mangroves, that is sometimes compatible with academic knowledge.

  15. EU Regulatory Risk Management of Marine Biotoxins in the Marine Bivalve Mollusc Food-Chain

    Directory of Open Access Journals (Sweden)

    Micheál O’Mahony

    2018-03-01

    Full Text Available Food safety risk assessment in the European Union (EU recognises consumer illness that arises from marine biotoxins as a risk associated with bivalve mollusc consumption. EU food regulations contain various general food safety obligations, which should contribute significantly to managing this risk. EU food regulations additionally impose various specific obligations on both Food Business Operators and Competent Authorities in order to manage the marine biotoxin food safety risk in the bivalve mollusc food-chain. These have a particular focus on the pre-harvest component of the food-chain. A central component of these specific systems is the requirement for ongoing monitoring of phytoplankton and biotoxin concentrations in water and molluscs, respectively. This monitoring explicitly brings a potential outcome of closing production areas delineated by classification to prohibit the harvest of bivalve molluscs as food from those areas when acceptable biotoxin concentrations are exceeded. This review considers the utility of these systems, at conceptual and practical levels, and explores their contribution to an effective regulatory risk management approach.

  16. Bivalve molluscs of São Marcos locality, Medium Uruguay River Basin, Brazil

    Directory of Open Access Journals (Sweden)

    Édison Vicente Oliveira

    2007-12-01

    Full Text Available To verification of quali-quantitative it has been accomplished collected of bivalve molluscs during the period of twelve months, together with analysis of some abiotic variables in the middle care of Uruguay river, situated in São Marcos, Uruguaiana municipality. The place where the collects has been accomplished, were divided in three distinct spots, considerating the substract type predominant; sand, rock and mud. The individuals were collected using hands and with. The selection screen aid, of 0.8mm size net and were conserved in a dry environment. They had been collected a total of 1,022 units of bivalves, wich belong to 12 taxa, being that of these only specimens Cyanocyclas limosa and Diplodon parallelopipedon had been captured alive (tanatocenosis. It had great quantitative predominance of Corbicula fluminea and Diplodon uruguayensis. With exception of bivalves invading, the too much species had been collected only in the slimy substratum. Other species occurrence were Mycetopoda siliquosa and Anodontites trigonus, there two species a vulnerable to extinction in Rio Grande do Sul.

  17. Stress detection in bivalve mollusk using non-invasive bioelectric monitoring of myoneural behavior

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, E.L.; Hardison, B.S. [Tennessee Technological Univ., Cookeville, TN (United States). Dept. of Biology; Dawson, V.K.; Waller, D. [National Fisheries Research Center, La Crosse, WI (United States); Waller, W.T.; Dickson, K.L.; Allen, H.J. [Univ. of North Texas, Denton, TX (United States). Inst. of Applied Sciences

    1995-12-31

    Few studies have demonstrated cause-and-effect linkages between extrinsic environmental factors and intrinsic bioelectric action potentials of bivalve mollusk using non-invasive, non-destructive approaches. A non-invasive, external probe configuration and detection system, similar to one used previously with native unionids, was developed for continuously monitoring bioelectric activities of clams and mussels. Using remote probes and differential amplifiers, bioelectric activities were recorded for cardiac, adductor, siphon and foot responses using a computer equipped with integrating software. To test if remote, non-invasive probes would detect similar information to that recorded by invasive needle electrodes, two individuals of zebra mussel (Dreissenia polymorpha), and Asiatic clam (Corbicula fluminea) were each configured with two sets of probes. One set was inserted between the valves and along the inside surface of the shelf; the other set was positioned remotely about the outside margins of the valves. Signal validation was made by simultaneously recording bioelectric responses for the same animal from both sets of probes. In preliminary stress tests monitored bivalves were subjected to changes in temperatures over 2 to 3 hr intervals from ambient to potentially lethal levels (20 to 30 C for zebra, 25 C to 40 C for corbicula). Dramatic increases resulted in both number and amplitude of cardiac events as temperature increased. Planned studies will use this approach to evaluate bivalve myoneural behavior patterns in response to chemical and non-chemical stimuli.

  18. Internal distribution of uranium and associated genotoxic damages in the chronically exposed bivalve Corbicula fluminea

    Energy Technology Data Exchange (ETDEWEB)

    Simon, Olivier, E-mail: olivier.simon@irsn.fr [Laboratoire de Radioecologie et Ecotoxicologie, Institut de Radioprotection et de Surete Nucleaire, Cadarache, Bat, 186 BP3, 13115 Saint Paul-Lez-Durance Cedex (France); Floriani, Magali; Cavalie, Isabelle; Camilleri, Virginie; Adam, Christelle; Gilbin, Rodolphe; Garnier-Laplace, Jacqueline [Laboratoire de Radioecologie et Ecotoxicologie, Institut de Radioprotection et de Surete Nucleaire, Cadarache, Bat, 186 BP3, 13115 Saint Paul-Lez-Durance Cedex (France)

    2011-08-15

    Uranium (U) internal distribution and involved effects in the bivalve Corbicula fluminea have been studied after direct chronic exposure (90 d, 10 {mu}g.L-1). U distribution was assessed at the subcellular level (Metal Rich Granules -MRG-, pellets and cytosol fractions) in two main organs of the bivalve (gills and visceral mass). Micro-localisation was investigated by TEM-EDX analysis in the gills epithelium. DNA damage in gill and hemolymph samples was measured by the Comet assay. The 90-d exposure period led to a significant increase of U concentration in gills over time (x5) and a large U quantity in subcellular granules in gills. Finally, a significant increase (x2) in DNA damage was noted in exposed gills and haemocytes. This study shows that the accumulation levels and consequently the potential toxicity cannot be successfully predicted only on the basis of concentration in water or in tissues and subcellular fractions after chronic exposure. - Highlights: > Relevant information concerning the chronic impact of uranium on biota is scarce. > We study its biological speciation to explain bioavailability, accumulation, toxicity. > 80% of U accumulated was measured in the pellet fraction (organelles + granules/MRG). > Chronic exposure to U induced genetic damage in gill and haemolymph cells of the bivalve.

  19. Dinophysis caudata generated lipophilic shellfish toxins in bivalves from the Nanji Islands, East China Sea

    Science.gov (United States)

    Jiang, Tao; Xu, Yixiao; Li, Yang; Qi, Yuzao; Jiang, Tianjiu; Wu, Feng; Zhang, Fan

    2014-01-01

    A 12-month program of monitoring potentially toxic microalgae (that produce lipophilic shellfish toxins; LSTs) and their toxins in bivalves was conducted from April 2006 to March 2007 in the Nanji Islands, East China Sea. Two Dinophysis species, D. caudata and D. acuminata, were identified, and D. caudata was found to be the dominant species. D. caudata was detected in water samples between April and June 2006, and between February and March 2007. It reached its highest abundances in May, with a mean abundance of 1.38×102 cells/L in surface water and 1.25×102 cells/L in bottom water (cultured bivalves sampled between April and June were contaminated with LSTs, with an average toxicity of 85 μg okadaic acid (OA) eq./100 g meat, which was four times higher than the Chinese regulatory limit (20 μg OA eq./100 g meat). Ten out of fifteen wild samples (66.7%) collected during the same period were positive for LSTs, and contained an average LST toxicity of 45 μg OA eq./100 g meat (more than twice the regulatory value). Cultured Patinopecten yessoensis collected on 15 May 2006 had the highest toxicity, 320 μg OA eq./100 g meat, and relatively high toxicities (80 to 160 μg OA eq./100 g meat) were found in bivalves until the end of July.

  20. Availability of pearl producing marine bivalves in south-eastern coast of Bangladesh and culture potentialities

    Directory of Open Access Journals (Sweden)

    Md Ataur Rahman

    2015-12-01

    Full Text Available The present study was conducted during September 2014 to July 2015 to identify the pearl bearing bivalves in south-eastern coast of Bangladesh and culture potentialities of marine oyster in captivity based on field investigation. A total of 7 pearl bearing bivalve species were identified in the coast with a salinity of 18-34 ppt, pH 8.1-8.3 and water depth ranged 0.2-2.0 meter in their habitat. From the collected bivalves, most abundant oyster species windowpane oyster, Placuna placenta (Linnaeus, 1758 was reared in fiber glass tanks with seawater for a period of 6 months. During rearing highest survival rate of 88% was observed in T1 with sandy and gravel substratum and lowest survival rate of 78% was found in T2 with muddy substratum. Average temperature and salinity were varied between 24 °C-25 °C and 21-26 ppt respectively. From the reared oyster, highest 54 nos. small pearls in the month of April and lowest 7 pearls in December from a single P. placenta were obtained. The study proved that pearls can be obtained from the marine oysters in captivity in Bangladesh, and this offers large scale culture potentialities in our coast.

  1. EU Regulatory Risk Management of Marine Biotoxins in the Marine Bivalve Mollusc Food-Chain.

    Science.gov (United States)

    O'Mahony, Micheál

    2018-03-10

    Food safety risk assessment in the European Union (EU) recognises consumer illness that arises from marine biotoxins as a risk associated with bivalve mollusc consumption. EU food regulations contain various general food safety obligations, which should contribute significantly to managing this risk. EU food regulations additionally impose various specific obligations on both Food Business Operators and Competent Authorities in order to manage the marine biotoxin food safety risk in the bivalve mollusc food-chain. These have a particular focus on the pre-harvest component of the food-chain. A central component of these specific systems is the requirement for ongoing monitoring of phytoplankton and biotoxin concentrations in water and molluscs, respectively. This monitoring explicitly brings a potential outcome of closing production areas delineated by classification to prohibit the harvest of bivalve molluscs as food from those areas when acceptable biotoxin concentrations are exceeded. This review considers the utility of these systems, at conceptual and practical levels, and explores their contribution to an effective regulatory risk management approach.

  2. Molecular Phylogeny and Morphological Distinctions of Two Popular Bivalves, Ctenoides scaber and Ctenoides mitis

    Directory of Open Access Journals (Sweden)

    Lindsey F. Dougherty

    2017-01-01

    Full Text Available One of the most well-known species in the bivalve family Limidae (d’Orbigny, 1846 is the brightly colored Ctenoides scaber (Born, 1778, commonly known as the rough file clam or flame scallop. Distinguishing this bivalve from its close relative, C. mitis (Lamarck, 1807, can be difficult using only morphological features and has led to much taxonomic confusion throughout the literature. In this study, morphological characters were compared to a molecular phylogeny constructed using three genes (COI, 28S, and H3 in order to differentiate C. scaber and C. mitis. The phylogeny recovered two well-supported clades that differ significantly in shell rib numbers, but not tentacle colors. The two species were then placed in a larger phylogenetic context of the Limidae family, which revealed the need for further systematic revision across genera. As these bivalves are popular in aquaria, cannot be tank-raised, and have been overcollected in the past, proper species identification is important for assessing sustainable collection practices.

  3. Investigation of Nematopsis spp. oocysts in 7 species of bivalves from Chonburi province, Gulf of Thailand.

    Science.gov (United States)

    Tuntiwaranuruk, C; Chalermwat, K; Upatham, E S; Kruatrachue, M; Azevedo, C

    2004-01-28

    This is the first detailed report of Nematopsis spp. in Thai bivalves. A monthly survey was conducted on 7 species of commercial bivalves from Chonburi province, on the eastern seaboard of Thailand, from November 2000 to November 2001 to investigate the prevalence of the apicomplexan parasite Nematopsis Schneider, 1892. Nematopsis spp. sporozoites were found in the cultivated bivalves Arcuatula arcuatula, Anadara granosa and Perna viridis as well as the locally harvested Paphia undulata. They were not found in Donax faba, Meretrix meretrix or Saccostrea cucullata. Using light microscopy, we were able to identiby 4 oocyst morphotypes of the gregarine Nematopsis spp. Prevalence of Nematopsis spp. during the 13 mo sampling period was highest in A. arcuatula (91.8%; n = 110) and lowest in A. granosa (59.2%; n = 130). The morphology of the oocysts differed between hosts, with an average (x +/- SD) length/width of 16.28 +/- 0.64/12.01 +/- 0.35 microm (n = 50) for A. arcuatula, 16.90 +/- 0.71/12.69 +/- 0.33 microm (n = 50) for A. granosa, 17.61 +/- 0.69/12.72 +/- 0.36 microm (n = 50) for P. viridis, and 11.21 +/- 0.62/8.55 +/- 0.52 microm (n = 50) for P. undulata. Identification of oocysts of these apicomplexan gregarines to species was not attempted. The prevalence of infection in relation to habitat and time of sampling is discussed.

  4. Clinical manifestation of mitochondrial diseases.

    Science.gov (United States)

    Magner, Martin; Kolářová, Hana; Honzik, Tomáš; Švandová, Ivana; Zeman, Jiří

    2015-01-01

    Mitochondrial disorders (MD) represent a clinically, biochemically and genetically heterogeneous group of diseases associated with dysfunction of the oxidative phosphorylation system and pyruvate dehydrogenase complex. Our aim was to illustrate the most common clinical presentation of MD on the example of selected diseases and syndromes. The minimal prevalence of MD is estimated as 1 to 5,000. MD may manifest at any age since birth until late-adulthood with acute manifestation or as a chronic progressive disease. Virtually any organ may be impaired, but the organs with the highest energetic demands are most frequently involved, including brain, muscle, heart and liver. Some MD may manifest as a characteristic cluster of clinical features (e.g. MELAS syndrome, Kearns-Sayre syndrome). Diagnostics includes detailed history, the comprehensive clinical examination, results of specialized examinations (especially cardiology, visual fundus examination, brain imaging, EMG), laboratory testing of body fluids (lactate, aminoacids, organic acids), and analysis of bioptic samples of muscle, skin, and liver, eventually. Normal lactate level in blood does not exclude the possibility of MD. Although the aimed molecular genetic analyses may be indicated in some of mitochondrial diseases, the methods of next generation sequencing come into focus. Examples of treatment are arginine supplementation in MELAS syndrome, ketogenic diet in pyruvate oxidation disorders or quinone analogs in patients with LHON. Conclusion: The clinical suspicion of a mitochondrial disorder is often delayed, or the disease remains undiagnosed. The correct diagnosis and adequate treatment can improve prognosis of the patient. Access to genetic counseling is also of great importance.

  5. Uveitis--manifestation af syfilis

    DEFF Research Database (Denmark)

    Andersen, Ellen Sloth; Kofoed, Kristian; Andersen, Mads Varis Nis

    2007-01-01

    We describe two cases of neurosyphilis whose diagnosis was based on ocular symptoms. Both patients were treated in the Eye Department for bilateral uveitis, and they were tested serologically positive for syphilis. The diagnoses of neurosyphilis were confirmed by demonstration of CSF pleocytosis...... and specific intrathecal antibody production. Both patients were treated with 21 million units of penicillin IV daily for 15 days. Ocular syphilis is an unusual manifestation of the disease but should be considered in patients with uveitis of uncertain origin, especially if the patient has a rash and...

  6. Liver manifestations of cystic fibrosis

    International Nuclear Information System (INIS)

    Akata, Deniz; Akhan, Okan

    2007-01-01

    Chronic liver disease is one of the major complications of cystic fibrosis (CF). Significant liver disease is seen in 13-25% of children with CF. Improved life expectancy and prolonged follow-up have favored better characterization of the hepatic manifestations of CF and allowed direct observation of an increasing number of liver-related events. Liver disease typically develops in the first decade of life, with the incidence dropping rapidly after the age of 10 years. The wide spectrum of liver disease ranging from asymptomatic gallbladder abnormalities to biliary cirrhosis will be reviewed in this article

  7. Zeolitization at uranium ore manifestation

    International Nuclear Information System (INIS)

    Petrosyan, R.V.; Buntikova, A.F.

    1981-01-01

    The process of zeolitization at uranium ore manifestation is studied. A specific type of low-temperature wall endogenous alteration of rocks due to the effect of primary acid solution with low content of carbonic acid is established. Leaching of calcium from enclosing rocks and its deposition in ore-accompanying calcium zeolites is a characteristic feature of wall-metasomatosis. Formation of desmin- calcite-laumontite and quartz-fluoroapatite of vein associations, including ore minerals (uranophane and metaotenite), is genetically connected with calcium metasomatosis. On the basis of the connection of ore minerals with endogeneous process of zeolitization a conclusion can be made on endogenous origin of uranophane and metaotenite [ru

  8. Gastrointestinal manifestations of mitochondrial disease.

    Science.gov (United States)

    Gillis, Lynette A; Sokol, Ronald J

    2003-09-01

    Although non-specific gastrointestinal and hepatic symptoms are commonly found in most mitochondrial disorders, they are among the cardinal manifestations of several primary mitochondrial diseases, such as: mitochondrial neurogastrointestinal encephalomyopathy; mitochondrial DNA depletion syndrome; Alpers syndrome; and Pearson syndrome. Management of these heterogeneous disorders includes the empiric supplementation with various "mitochondrial cocktails," supportive therapies, and avoidance of drugs and conditions known to have a detrimental effect on the respiratory chain. There is a great need for improved methods of treatment and controlled clinical trials of existing therapies. Liver transplantation is successful in acquired cases; however neuromuscular involvement in primary mitochondrial disorders should be a contraindication for liver transplantation.

  9. Cutaneous manifestations of chikungunya fever.

    Science.gov (United States)

    Seetharam, K A; Sridevi, K; Vidyasagar, P

    2012-01-01

    Chikungunya fever, a re-emerging RNA viral infection produces different cutaneous manifestations in children compared to adults. 52 children with chikungunya fever, confirmed by positive IgM antibody test were seen during 2009-2010. Pigmentary lesions were common (27/52) followed by vesiculobullous lesions (16/52) and maculopapular lesions (14/52). Vesiculobullous lesions were most common in infants, although rarely reported in adults. Psoriasis was exacerbated in 4 children resulting in more severe forms. In 2 children, guttate psoriasis was observed for the first time.

  10. Neurological manifestation of colonic adenocarcinoma

    Directory of Open Access Journals (Sweden)

    Uzair Chaudhary

    2012-04-01

    Full Text Available Paraneoplastic neurologic disorders are extremely rare in cancer patients and are most commonly associated with certain tumors, such as ovarian cancer, small cell lung cancer, and breast cancer. We report here a paraneoplastic neurological syndrome in a 53-year-old man with colonic adenocarcinoma with a solitary liver metastasis. His paraneoplastic syndrome was successfully treated by methylprednisolone and primary oncologic therapies including neoadjuvant chemotherapy and definitive surgery. This is also the first documented case of simultaneous manifestation of a sensory neuropathy and limbic encephalitis with colon cancer.

  11. Extraintestinal manifestations of celiac disease.

    Science.gov (United States)

    Hernandez, Lincoln; Green, Peter H

    2006-10-01

    Celiac disease is an autoimmune disorder that occurs in genetically predisposed individuals as the result of an immune response to gluten. It is present in approximately 1% of the population. Diarrhea has become a less common mode of presentation (dermatitis herpetiforme, and neurologic disorders, mainly peripheral neuropathy and ataxia. Arthritis is commonly found in patients with celiac disease when systematically sought. Overall, autoimmune diseases occur more frequently (three to ten times more) in those with celiac disease than in the general population. A gluten-free diet is the standard of treatment, although its effect on some of the extraintestinal manifestations remains to be determined.

  12. Cutaneous manifestations associated with melanoma.

    Science.gov (United States)

    Vyas, Ritva; Selph, Jacqueline; Gerstenblith, Meg R

    2016-06-01

    Melanoma is a malignancy most commonly arising from the skin; therefore, primary melanoma characteristics are usually the first cutaneous manifestations of melanoma. Cutaneous metastases, which can occur locally or diffusely, are important to detect in a timely manner as treatments for advanced melanoma that impact survival are now available. Melanoma can be associated with local or diffuse pigmentation changes, including depigmentation associated with the leukodermas and hyperpigmentation associated with diffuse melanosis cutis. The leukodermas occur frequently, illustrate the immunogenic nature of melanoma, and may impact prognosis. Paraneoplastic syndromes in association with melanoma are rare, though can occur. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Neurological Manifestations of Dengue Infection

    Directory of Open Access Journals (Sweden)

    Guo-Hong Li

    2017-10-01

    Full Text Available Dengue counts among the most commonly encountered arboviral diseases, representing the fastest spreading tropical illness in the world. It is prevalent in 128 countries, and each year >2.5 billion people are at risk of dengue virus infection worldwide. Neurological signs of dengue infection are increasingly reported. In this review, the main neurological complications of dengue virus infection, such as central nervous system (CNS, peripheral nervous system, and ophthalmic complications were discussed according to clinical features, treatment and possible pathogenesis. In addition, neurological complications in children were assessed due to their atypical clinical features. Finally, dengue infection and Japanese encephalitis were compared for pathogenesis and main clinical manifestations.

  14. Oral manifestations of celiac disease.

    Science.gov (United States)

    Pastore, Luca; Carroccio, Antonio; Compilato, Domenico; Panzarella, Vera; Serpico, Rosario; Lo Muzio, Lorenzo

    2008-03-01

    Contrary to early beliefs, celiac disease (CD) is relatively common; however, it still remains underdiagnosed since most cases are atypical, with few or no gastrointestinal symptoms and predominance of extraintestinal manifestations. As a consequence, the diagnosis of the disorder often requires a multidisciplinary approach. Also some oral ailments have been described in celiac patients. In this study, we review the papers that have reported oral manifestations in subjects with CD. A comprehensive literature search was conducted in Medline and Embase databases using appropriate key words. Additional papers were selected by cross-referencing from the retrieved articles. Dental enamel defects are the oral lesions most closely related to CD. There are conflicting data on the association between CD and recurrent aphthous stomatitis. A correlation of CD with atrophic glossitis has been reported, although robust evidence in support of it is lacking. Patients with CD have caries indexes seemingly lower than healthy individuals, but they may experience delay in tooth eruption. Occurrence of other oral mucosal lesions in CD subjects is likely occasional. Patients with systematic dental enamel defects should be screened for CD even in the absence of gastrointestinal symptoms. CD screening tests for patients with oral aphthae or idiopathic atrophic glossitis should be selectively considered during a medical evaluation that focuses on all aspects of the patient's status.

  15. Oral manifestations of acute leukaemia

    Directory of Open Access Journals (Sweden)

    Ivanović Mirjana

    2011-01-01

    Full Text Available Acute leukaemia is the most common form of chilhood cancer. The aim of this paper was to underline the importance of oral manifestations in children with acute leukaemia. The disease and its treatment can directly or indirectly affect oral health. Oral manifestations are gingival inflammation and enlargement. Leukaemic cells are capable of infiltrating the gingiva and the deeper periodontal tissues which leads to ulceration and infection of oral tissues. Gingival bleeding is a common sign in patients with leukaemia. Symptoms include local lymphadenopathy, mucous membrane Petechiae and ecchymoses. Cytotoxic drugs have direct effects like mucositis, involving atrophy, desquamation and ulceration of the mucosa, with increasing the risk for local and systemic infections. Leukaemia can directly influence dental care and dental treatment, while oral lesions may have life-threatening consequences. Knowledge and skills among dentists may also not be adequate to treat children with acute leukaemia. It is therefore imperative that all stomatologists be aware of dental problems that occur in leukaemia in order to be able to effectively carry out appropriate measures to mitigate these problems.

  16. Cutaneous manifestations of internal malignancy

    Directory of Open Access Journals (Sweden)

    A Ayyamperumal

    2012-01-01

    Full Text Available Background: Many malignancies affecting the internal organs display cutaneous manifestations which may be either specific (tumor metastases or nonspecific lesions. Aims: The study is aimed at determining the frequency and significance of cutaneous manifestations among patients with internal malignancy. Materials and Methods: 750 cases of proven internal malignancy, who attended a cancer chemotherapy center in South India, were studied. Specific infiltrates were confirmed by histopathology, fine needle aspiration cytology (FNAC and marker studies. Results: Out of the 750 patients with internal malignancy, skin changes were seen in a total of 52 (6.93% patients. Conclusion: Cutaneous metastases (specific lesions were seen in 20 patients (2.66%: contiguous in 6 (0.8%, and non-contiguous in 14 (1.86%. Nonspecific skin changes were seen in 32 patients (4.26%. None of our patients presented with more than one type of skin lesions. Herpes zoster was the most common nonspecific lesion noticed in our patients, followed by generalized pruritus, multiple eruptive seborrheic keratoses, bullous disorder, erythroderma, flushing, purpura, pyoderma gangrenosum, insect bite allergy and lichenoid dermatitis.

  17. Uncharted waters: Bivalves of midway atoll and integrating mathematics into biology education

    Science.gov (United States)

    McCully, Kristin M.

    To protect and conserve the Earth's biodiversity and ecosystem services, it is important not only to understand and conserve species and ecosystems, but also to instill an understanding and appreciation for biodiversity and ecosystem services in the next generations of both scientists and citizens. Thus, this dissertation combines research into the ecology and identity of large bivalves at Midway Atoll in the Northwestern Hawaiian Islands (NWHI) with research on pedagogical strategies for integrating mathematics into undergraduate biology education. The NWHI is one of the few remaining large, mainly intact, predator-dominated coral reef ecosystems and one of the world's largest marine protected areas. Previous bivalve studies focused on the black-lipped pearl oyster, Pinctada margaritifera, which was heavily harvested in the late 1920s, has not recovered, and is now a candidate species for restoration. First, I combined remote sensing, geographic information systems, SCUBA, and mathematical modeling to quantify the abundance, spatial distributions, and filtration capacity of large epifaunal bivalves at Midway Atoll. These bivalves are most abundant on the forereef outside the atoll, but densities are much lower than reported on other reefs, and Midway's bivalves are unlikely to affect plankton abundance and productivity inside the lagoon. Second, I used molecular techniques and phylogenetic reconstructions to identify pearl oysters (Pinctada) from Midway Atoll as P. maculata , a species not previously reported in Hawaii. As a small morphologically cryptic species, P. maculata may be a native species that has not been collected previously, a native species that has been identified incorrectly as the morphologically similar P. radiata, or it may be a recent introduction or natural range extension from the western Pacific. Finally, I review science education literature integrating mathematics into undergraduate biology curricula, and then present and evaluate a

  18. Burrowing criteria and burrowing mode adjustment in bivalves to varying geoenvironmental conditions in intertidal flats and beaches.

    Directory of Open Access Journals (Sweden)

    Shinji Sassa

    Full Text Available The response of bivalves to their abiotic environment has been widely studied in relation to hydroenvironmental conditions, sediment types and sediment grain sizes. However, the possible role of varying geoenvironmental conditions in their habitats remains poorly understood. Here, we show that the hardness of the surficial intertidal sediments varies by a factor of 20-50 due to suction development and suction-induced void state changes in the essentially saturated states of intertidal flats and beaches. We investigated the response of two species of bivalves, Ruditapes philippinarum and Donax semigranosus, in the laboratory by simulating such prevailing geoenvironmental conditions in the field. The experimental results demonstrate that the bivalve responses depended strongly on the varying geoenvironmental conditions. Notably, both bivalves consistently shifted their burrowing modes, reducing the burrowing angle and burial depth, in response to increasing hardness, to compensate for the excessive energy required for burrowing, as explained by a proposed conceptual model. This burrowing mode adjustment was accompanied by two burrowing criteria below or above which the bivalves accomplished vertical burrowing or failed to burrow, respectively. The suitable and fatal conditions differed markedly with species and shell lengths. The acute sensitivities of the observed bivalve responses to geoenvironmental changes revealed two distinctive mechanisms accounting for the adult-juvenile spatial distributions of Ruditapes philippinarum and the behavioral adaptation to a rapidly changing geoenvironment of Donax semigranosus. The present results may provide a rational basis by which to understand the ensuing, and to predict future, bivalve responses to geoenvironmental changes in intertidal zones.

  19. Musculoskeletal manifestations of diabetes mellitus.

    Science.gov (United States)

    Merashli, M; Chowdhury, T A; Jawad, A S M

    2015-11-01

    The prevalence of Type 1 and Type 2 diabetes are increasing significantly worldwide. Whilst vascular complications of diabetes are well recognized, and account for principle mortality and morbidity from the condition, musculoskeletal manifestations of diabetes are common and whilst not life threatening, are an important cause of morbidity, pain and disability. Joints affected by diabetes include peripheral joints and the axial skeleton. Charcot neuroarthropathy is an important cause of deformity and amputation associated with peripheral neuropathy. A number of fibrosing conditions of the hands and shoulder are recognized, including carpal tunnel syndrome, adhesive capsulitis, tenosynovitis and limited joint mobility. People with diabetes are more prone to gout and osteoporosis. Management of these conditions requires early recognition and close liaison between diabetes and rheumatology specialists. © The Author 2015. Published by Oxford University Press on behalf of the Association of Physicians. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Atypical manifestations of early syphilis

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    R V Koranne

    1990-01-01

    Full Text Available A study of 36 untreated patients with early syphilis revealed atypical variations namely; long incubation period of 101 days in I patient, more than 3 chancres in 1, undermined margin of the chancre along with tenderness in 1 and moderate to severe tenderness of the ulcers in 2 cases. In 3 patients there was no indurations of the ulcers. Three patients with primary syphilis had unilateral lymphadenitis, and in I case the lymph nodes were not only tender but showed tendency towardsmatingawell. Insecondarysyphilis, 11 out of 16 patients having condylomata lata had no other muco-cutaneous lesions. Concomitant presence of other venereal disease to account for the atypical manifestations was discounted- by appropriate laboratory tests, response to therapeutic agents and follow up.

  1. Musculoskeletal manifestations of bacterial endocarditis

    Directory of Open Access Journals (Sweden)

    Érika Bevilaqua Rangel

    2000-09-01

    Full Text Available CONTEXT: The incidence of staphylococcal infection has been increasing during the last 20 years. OBJECTIVE: Report a case of staphylococcal endocarditis preceded by musculoskeletal manifestations, which is a rare form of clinical presentation. DESIGN: Case report. CASE REPORT: A 45-year-old-man, without addictions and without known previous cardiopathy, was diagnosed as having definitive acute bacterial endocarditis due to Staphylococcus aureus. Its etiology was community-acquired, arising from a non-apparent primary focus. In addition, the musculoskeletal symptoms preceded the infective endocarditis (IE by about 1 month, which occurred together with other symptoms, e.g. mycotic aneurysms and petechiae. Later, the patient showed perforation of the mitral valve and moderate mitral insufficiency with clinical control.

  2. Atypical manifestations of tinea faciei

    Directory of Open Access Journals (Sweden)

    Mittal R

    1996-01-01

    Full Text Available A study of 58 paitents of tinea faciei was conducted. Twenty five (43.1% patients had history of photosensitivity. Twenty eight (48.2% patients were applying topical steroids, 2 (3.4% patients were on 10 mg of prednisolone daily. Associated tinea of other sites were observed in 14 (24.13%. 23 (39.6% patients had typical circinate, arcuate, annular plaques with raised margin showing vesiculo-pustules. Atypical manifestations were in the form of arcuate plaques on the pinna in 4 patients, erythematous plaques full of vesiculo-pustules without central clearing in 3. Thirty two (55.17% patients had plaques with broad edges and indistinct central clearing. In 2 patients lesions resembled discoid lupus erythematosus. Skin scrapings for fungus was positive in 36 (62.06% cases. All patients responded to systemic griseofulvin 10mg/kg with 1% clotrimazole topicaly in 4-8 weeks.

  3. CT manifestations of liver abscess

    International Nuclear Information System (INIS)

    Yan Jianfeng; Peng Yongjun

    2006-01-01

    Objective: To study CT findings of hepatic abscess. Methods: CT findings and clinical materials of 38 patients with liver abscess verified by aspiration were retrospectively viewed. All patients were examined by non-enhanced and contrast enhanced CT. Results: In 25 cases, inhomogeneous hypodense lesions with unclear demarcation were found on non-enhanced CT. On contrast enhanced CT scan, target or cluster enhancement was found Additionally, air was found within some lesions. In the rest 13 cases with early stage liver abscess, no typical sign was found on non-enhanced CT, while rosette sign and continued enhancement sign were demonstrated after the contrast agent was given. Conclusion: Various CT findings are found in different stages of liver abscess. The diagnosis and differential diagnosis should be based on CT manifestations and clinical history as well. (authors)

  4. Bioaccumulation of heavy metals and health risk assessment in three benthic bivalves along the coast of Laizhou Bay, China.

    Science.gov (United States)

    Liu, Jinhu; Cao, Liang; Dou, Shuozeng

    2017-04-15

    This study investigated the tissue- and species-specific bioaccumulation of heavy metals (Cr, Cu, Hg, Zn, As, Cd, and Pb) in three benthic bivalves (the ark shell, Scapharca subcrenata; the surf clam, Mactra veneriformis; and the Manila clam, Ruditapes philippinarum) collected from the coast of Laizhou Bay in the Bohai Sea. The results demonstrated that the visceral masses of the bivalves tended to accumulate heavy metals more efficiently than their muscles. The capacities of the bivalves to bioaccumulate metals followed a similar order: Cd>Hg>Zn=As>Cu>Cr=Pb. The conditions of metal contamination in the bivalves tended to be worse along the eastern coast than in other regions. Overall, the Manila clam was more severely contaminated by heavy metals than the surf clam and ark shell. Judging by the hazard quotients (HQ) of the metals in the muscles of the bivalves, the greatest hazard risk to human health comes primarily from As. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Validating the Incorporation of 13C and 15N in a Shorebird That Consumes an Isotopically Distinct Chemosymbiotic Bivalve.

    Science.gov (United States)

    van Gils, Jan A; Ahmedou Salem, Mohamed Vall

    2015-01-01

    The wealth of field studies using stable isotopes to make inferences about animal diets require controlled validation experiments to make proper interpretations. Despite several pleas in the literature for such experiments, validation studies are still lagging behind, notably in consumers dwelling in chemosynthesis-based ecosystems. In this paper we present such a validation experiment for the incorporation of 13C and 15N in the blood plasma of a medium-sized shorebird, the red knot (Calidris canutus canutus), consuming a chemosymbiotic lucinid bivalve (Loripes lucinalis). Because this bivalve forms a symbiosis with chemoautotrophic sulphide-oxidizing bacteria living inside its gill, the bivalve is isotopically distinct from 'normal' bivalves whose food has a photosynthetic basis. Here we experimentally tested the hypothesis that isotope discrimination and incorporation dynamics are different when consuming such chemosynthesis-based prey. The experiment showed that neither the isotopic discrimination factor, nor isotopic turnover time, differed between birds consuming the chemosymbiotic lucinid and a control group consuming a photosynthesis-based bivalve. This was true for 13C as well as for 15N. However, in both groups the 15N discrimination factor was much higher than expected, which probably had to do with the birds losing body mass over the course of the experiment.

  6. Validating the Incorporation of 13C and 15N in a Shorebird That Consumes an Isotopically Distinct Chemosymbiotic Bivalve.

    Directory of Open Access Journals (Sweden)

    Jan A van Gils

    Full Text Available The wealth of field studies using stable isotopes to make inferences about animal diets require controlled validation experiments to make proper interpretations. Despite several pleas in the literature for such experiments, validation studies are still lagging behind, notably in consumers dwelling in chemosynthesis-based ecosystems. In this paper we present such a validation experiment for the incorporation of 13C and 15N in the blood plasma of a medium-sized shorebird, the red knot (Calidris canutus canutus, consuming a chemosymbiotic lucinid bivalve (Loripes lucinalis. Because this bivalve forms a symbiosis with chemoautotrophic sulphide-oxidizing bacteria living inside its gill, the bivalve is isotopically distinct from 'normal' bivalves whose food has a photosynthetic basis. Here we experimentally tested the hypothesis that isotope discrimination and incorporation dynamics are different when consuming such chemosynthesis-based prey. The experiment showed that neither the isotopic discrimination factor, nor isotopic turnover time, differed between birds consuming the chemosymbiotic lucinid and a control group consuming a photosynthesis-based bivalve. This was true for 13C as well as for 15N. However, in both groups the 15N discrimination factor was much higher than expected, which probably had to do with the birds losing body mass over the course of the experiment.

  7. Extraintestinal manifestations of inflammatory bowel disease: epidemiology, diagnosis, and management

    DEFF Research Database (Denmark)

    Larsen, Signe; Bendtzen, Klaus; Nielsen, Ole Haagen

    2010-01-01

    ', 'bronchiectasis', 'bronchitis', 'cutaneous manifestations', 'erythema nodosum', 'extraintestinal manifestations', 'hyperhomocysteinemia', 'infliximab', 'iridocyclitis', 'lung disease', 'ocular manifestations', 'osteomalacia', 'pancreatitis', 'primary sclerosing cholangitis', 'renal stones', 'sulfasalazine...

  8. Characterizing Photosymbiosis Between Fraginae Bivalves and Symbiodinium Using Phylogenetics and Stable Isotopes

    Directory of Open Access Journals (Sweden)

    Jingchun Li

    2018-04-01

    Full Text Available Photosymbiotic associations between heterotrophic hosts and photosynthetic algae play crucial roles in maintaining the trophic and structural integrity of coral reef ecosystems. The marine bivalve subfamily Fraginae contains both non-symbiotic and photosymbiotic lineages, making it an ideal comparative system to study the origin and evolutionary adaptations of photosymbiosis. The symbiotic species exhibit unique morphological adaptations to photosymbiosis. However, the basic biology of these photosymbiotic relationships, such as symbiont diversity and nutritional benefits, has not been thoroughly characterized. In this study, we examined the general morphology of four Fraginae species occupying different depths (0–10 m: Corculum cardissa, Fragum fragum, Fragum scruposum, and Fragum sueziense. Abundant symbionts were found in the mantle, gill, and part of the foot, contained in tubular networks within host tissues. We used molecular phylogenetics to investigate the algal symbiont community of these Fraginae species. Results showed that symbionts from all four species are dinoflagellates belonging to the Symbiodinium clade C and we did not detect any host-specific or geographic-specific genetic structures within the symbionts. We also used stable carbon isotope analyses to examine whether the cockles are directly utilizing photosynthetically derived carbon sources. All species show less depleted 13C compared to filter-feeding bivalves, suggesting at least part of their organic carbon is derived directly from the symbionts. However, 13C depletion of Fragum sueziense collected from deeper habitats are less distinguishable from filter-feeding bivalves. This indicates that species in deeper habitats may rely less on photosymbiosis due to the reduced light availability. Given that the symbiotic fragines exhibit varying morphologies, habitats, and utilization of symbiont photosynthesis, the subfamily represents an ideal model system to study

  9. Prevalence of Calicivirus and Hepatitis A virus in bivalve molluscs from Galicia

    Directory of Open Access Journals (Sweden)

    Cristina Álvarez

    2014-06-01

    Full Text Available From a virological standpoint, shellfish safety continues to be a sanitary challenge. Bivalves are one of the most common vehicles of viral illness and the adoption of viral standards into European Union legislation is being considered. In this study, a 18-months survey were conducted in ten harvesting areas from two estuaries in Galicia (NW of Spain, the most important bivalve production area in Europe. Hepatitis A virus (HAV and human norovirus (NoV, including genogroups I (GI and II (GII were quantified by reverse transcription-real time PCR (RT-qPCR, according to the recently developed standard method ISO/TS 15216:2013. Four bivalve species were studied, including wild and cultured mussels (Mytilus galloprovincialis, clams (Venerupis philippinarum and V. decussata and cockles (Cerastoderma edule. Overall, 54.8% of the analysed samples were contaminated by at least one of the studied viruses, being detected the simultaneous presence of two or three viruses in 11.3% of the samples. NoV GI was the most prevalent virus (32.1% followed by NoV GII (25.6% and HAV (9.5%. The results showed the presence of viral contamination throughout the year in both areas and all species of molluscs. However, diverse patterns of prevalence and seasonality were observed among different viruses. HAV was detected only between March and June 2012. NoV GI was detected intermittently throughout the study period, with significant peaks in the spring and summer of 2011. NoV GII showed a clear seasonality to during the cold months by 2011; however, a significant peak was detected in the spring of 2012.

  10. Estimation of food limitation of bivalve larvae in coastal waters of north-western Europe

    DEFF Research Database (Denmark)

    Bos, O.G.; Hendriks, I.E.; Strasser, M.

    2006-01-01

    Marine invertebrate recruitment may be affected by food limitation during the pelagic larval life stages. In the present study, field data on abundance of bivalve larvae along with their prey (small phytoplankton) were examined to see whether they were consistent with predictions made...... assimilation rate averaged 7-26% of the maximum assimilation rate. Under the assumptions made for the present study, it is suggested that growth of larvae in north-west European waters is often food-limited. (c) 2005 Elsevier B.V. All rights reserved...

  11. Comparative sensitivity of European native (Anodonta anatina) and exotic (Corbicula fluminea) bivalves to mercury

    Science.gov (United States)

    Oliveira, Patrícia; Lopes-Lima, Manuel; Machado, Jorge; Guilhermino, Lúcia

    2015-12-01

    Pollution is believed to be an important factor modulating the competition between exotic invasive bivalves and their native competitors. Thus, the objective of the present study was to compare the sensitivity of the European native Anodonta anatina and the exotic invasive species Corbicula fluminea to mercury, a ubiquitous environmental contaminant of high concern. In laboratory acute bioassays, adult organisms of both species were exposed independently to mercury for 96 h (31-500 μg/L). The criteria indicative of toxicity were mortality and biomarkers of oxidative stress and damage, neurotoxicity, and energy production changes. Mercury induced mortality in A. anatina (72 h-LC10 and 72 h-LC50 of 14.0 μg/L and 49.6 μg/L, respectively) but not in C. fluminea. The ability of C. fluminea to maintaining the shell closed for considerable periods of time when exposed to high concentrations of mercury and the effective activation (up to 63 μg/L) of mechanisms against the oxidative stress caused by mercury may have contributed to its relatively low sensitivity. In the range of concentrations tested, mercury had no significant effects on the other parameters analysed in C. fluminea. Overall, the findings of the present study, suggest that in real scenarios of competition between C. fluminea and A. anatina populations, the presence of mercury may modulate the process, acting in favour of the exotic species because it is less sensitive to this environmental contaminant than the native bivalve. The results of the present study highlight the need of further investigation on the effects of mercury on the competition between exotic invasive species and their native competitors, especially the effects potentially induced by long-term exposure to low concentrations of this metal, the mechanisms involved in the tolerance to mercury-induced stress, and the potential post-exposure recovery of both exotic invasive and native bivalves. This knowledge is most important for

  12. Metallothionein coding sequence identification and seasonal mRNA expression of detoxification genes in the bivalve Corbicula fluminea.

    Science.gov (United States)

    Bigot, Aurélie; Doyen, Périne; Vasseur, Paule; Rodius, François

    2009-02-01

    The aim of this study was to identify a metallothionein (MT) coding sequence from the freshwater bivalve Corbicula fluminea and to measure the seasonal transcriptional pattern of MT in parallel with several detoxification genes: superoxide dismutase (SOD), catalase (CAT), glutathione S-transferases (GST) and glutathione peroxidases (GPx), in the digestive gland and the gills of this bivalve during a 1-year period. We identified a C. fluminea MT complete cDNA sequence using RT-PCR and RACE-PCR. The amino acid sequence deduced from the coding sequence encodes for a protein of 73 amino acids containing 21 cysteine residues. This protein exhibits high identities and similarities with the MT sequences of numerous bivalves. MT, SOD, CAT, pi-GST and Se-GPx expression patterns did not exhibit major seasonal variations. A slight increase of MT was observed in July. Therefore, the mRNA expression of these five genes could be used as biomarkers for monitoring studies.

  13. Evaluation of γ-radiation-induced DNA damage in two species of bivalves and their relative sensitivity using comet assay

    Energy Technology Data Exchange (ETDEWEB)

    Praveen Kumar, M.K., E-mail: here.praveen@gmail.com [Department of Zoology, Goa University, Goa 403206 (India); Shyama, S.K., E-mail: skshyama@gmail.com [Department of Zoology, Goa University, Goa 403206 (India); Sonaye, B.S. [Department of Radiation Oncology, Goa Medical College, Goa (India); Naik, U Roshini; Kadam, S.B.; Bipin, P.D.; D’costa, A. [Department of Zoology, Goa University, Goa 403206 (India); Chaubey, R.C. [Radiation Biology and Health Science Division, Bhabha Atomic Research Centre, Mumbai (India)

    2014-05-01

    Highlights: • Possible genotoxic effect of accidental exposure of aquatic fauna to γ radiation. • Relative sensitivity of bivalves to γ radiation is also analyzed using comet assay. • γ radiation induced significant genetic damage in both the species of bivalves. • P. malabarica and M. casta exhibited a similar level of sensitivity to γ radiation. • Comet assay may be used as a biomarker for the environmental biomonitoring. - Abstract: Ionizing radiation is known to induce genetic damage in diverse groups of organisms. Under accidental situations, large quantities of radioactive elements get released into the environment and radiation emitted from these radionuclides may adversely affect both the man and the non-human biota. The present study is aimed (a) to know the genotoxic effect of gamma radiation on aquatic fauna employing two species of selected bivalves, (b) to evaluate the possible use of ‘Comet assay’ for detecting genetic damage in haemocytes of bivalves as a biomarker for environmental biomonitoring and also (c) to compare the relative sensitivity of two species of bivalves viz. Paphia malabarica and Meretrix casta to gamma radiation. The comet assays was optimized and validated using different concentrations (18, 32 and 56 mg/L) of ethyl methanesulfonate (EMS), a direct-acting reference genotoxic agent, to which the bivalves were exposed for various times (24, 48 and 72 h). Bivalves were irradiated (single acute exposure) with 5 different doses (viz. 2, 4, 6, 8 and 10 Gy) of gamma radiation and their genotoxic effects on the haemocytes were studied using the comet assay. Haemolymph was collected from the adductor muscle at 24, 48 and 72 h of both EMS-exposed and irradiated bivalves and comet assay was carried out using standard protocol. A significant increase in DNA damage was observed as indicated by an increase in % tail DNA damage at different concentrations of EMS and all the doses of gamma radiation as compared to controls in

  14. Evaluation of γ-radiation-induced DNA damage in two species of bivalves and their relative sensitivity using comet assay

    International Nuclear Information System (INIS)

    Praveen Kumar, M.K.; Shyama, S.K.; Sonaye, B.S.; Naik, U Roshini; Kadam, S.B.; Bipin, P.D.; D’costa, A.; Chaubey, R.C.

    2014-01-01

    Highlights: • Possible genotoxic effect of accidental exposure of aquatic fauna to γ radiation. • Relative sensitivity of bivalves to γ radiation is also analyzed using comet assay. • γ radiation induced significant genetic damage in both the species of bivalves. • P. malabarica and M. casta exhibited a similar level of sensitivity to γ radiation. • Comet assay may be used as a biomarker for the environmental biomonitoring. - Abstract: Ionizing radiation is known to induce genetic damage in diverse groups of organisms. Under accidental situations, large quantities of radioactive elements get released into the environment and radiation emitted from these radionuclides may adversely affect both the man and the non-human biota. The present study is aimed (a) to know the genotoxic effect of gamma radiation on aquatic fauna employing two species of selected bivalves, (b) to evaluate the possible use of ‘Comet assay’ for detecting genetic damage in haemocytes of bivalves as a biomarker for environmental biomonitoring and also (c) to compare the relative sensitivity of two species of bivalves viz. Paphia malabarica and Meretrix casta to gamma radiation. The comet assays was optimized and validated using different concentrations (18, 32 and 56 mg/L) of ethyl methanesulfonate (EMS), a direct-acting reference genotoxic agent, to which the bivalves were exposed for various times (24, 48 and 72 h). Bivalves were irradiated (single acute exposure) with 5 different doses (viz. 2, 4, 6, 8 and 10 Gy) of gamma radiation and their genotoxic effects on the haemocytes were studied using the comet assay. Haemolymph was collected from the adductor muscle at 24, 48 and 72 h of both EMS-exposed and irradiated bivalves and comet assay was carried out using standard protocol. A significant increase in DNA damage was observed as indicated by an increase in % tail DNA damage at different concentrations of EMS and all the doses of gamma radiation as compared to controls in

  15. Radiological manifestations of intestinal tuberculosis

    International Nuclear Information System (INIS)

    Im, Jae Hoon

    1974-01-01

    Radiological findings of 87 cases of intestinal tuberculosis are analyzed and presented. The diagnosis was based on histopathology in 29 cases, and on clinical ground and radiological findings in 58 cases. The radio of male and female patients was 4:6, and peak incidence is between 10 and 30. Abdominal pain, diarrhea, weight loss, fever and general weakness are frequent symptoms, and tenderness of abdomen, ascites with abdominal distension, malnutrition and emaciation are frequent signs of the patients. Laboratory investigation reveal anemia, raised ESR, hypoalbuminaemia and positive occult blood reaction in the stool in most of the patients. Chest film show activity pulmonary tuberculosis in only 1/3 patients. There is no pathognomonic radiological findings in intestinal tuberculosis and their manifestations are protean, and differentiation from other inflammatory diseases and malignant tumors in gastrointestinal tract is very difficult on radiological ground alone. However, in patients with complaining vague abdominal symptoms and signs, the radiological diagnosis is most certain means in the decision of existence of organic lesion and suggestion of tuberculosis in the gastrointestinal tract and its extent as yet. Multiplicity of the lesion, involvement of adjacent organ such as peritoneum or mesenteric lymph nodes, typical nodularity or irregularity of mesenteric border and existence of active pulmonary tuberculosis are the suggestive findings of intestinal tuberculosis. In the diagnosis of inflammatory disease or malignant tumor of gastrointestinal tract, the possibility of tuberculosis should be borne in mind, and vice versa

  16. Mucocutaneous manifestations of HIV infection

    Directory of Open Access Journals (Sweden)

    Shobhana A

    2004-03-01

    Full Text Available BACKGROUND AND AIMS: Human immunodeficiency virus (HIV is associated with various mucocutaneous features, which may be the first pointer towards the existence of HIV infection. This study was done to note the different mucocutaneous lesions present in the HIV population in eastern India. METHODS: Four hundred and ten HIV seropositive patients attending the outpatient and inpatient departments were included in the study. RESULTS: Out of 410 HIV positives, 40% had mucocutaneous involvement at presentation. The mean age of the study population was 29 years and male to female ratio was 2.5:1. The common mucocutaneous morbidities included oral candidiasis (36%, dermatophytosis and gingivitis (13% each, herpes zoster (6%, herpes simplex and scabies (5% each. A striking feature, noted in 36% males, was straightening of hairs. Genital herpes was the commonest genital ulcer disease. Lesions associated with declining immunity included oral candidiasis, oral hairy leukoplakia and herpes zoster with median CD4 counts of 98, 62 and 198/ L respectively. CONCLUSION: Early recognition of mucocutaneous manifestations and associated STDs help in better management of HIV/AIDS.

  17. Neurologic manifestations of Angelman syndrome.

    Science.gov (United States)

    Thibert, Ronald L; Larson, Anna M; Hsieh, David T; Raby, Annabel R; Thiele, Elizabeth A

    2013-04-01

    Angelman syndrome is a neurogenetic disorder characterized by the loss or reduction of the ubiquitin-protein ligase E3A enzyme. Angelman syndrome results from a deletion or mutation of the maternally inherited 15q11.2-13.1 region, paternal uniparental disomy of chromosome 15, or an imprinting error. Epilepsy is common and may present with multiple seizure types, including nonconvulsive status epilepticus. Seizures are often intractable and typically require broad-spectrum antiepileptic medications. Dietary therapy has also proved successful in Angelman syndrome. Electroencephalographic patterns include notched δ and rhythmic θ activity and epileptiform discharges. Sleep disorders are also common, often characterized by abnormal sleep-wake cycles. Movement disorders are nearly universal in Angelman syndrome, most frequently presenting with ataxia and tremor. Neurocognitive impairment is always present to varying degrees, and expressive speech is typically severely affected. Individuals with Angelman syndrome often manifest psychiatric comorbidities including hyperactivity, anxiety, and challenging behaviors such as aggression and self-injury. We focus on a comprehensive whole-child approach to the diagnosis and long-term clinical care of individuals with Angelman syndrome. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. First record of a pontoniine shrimp (Caridea, Palaemonidae) in association with a boring bivalve of the genus Spengleria (Bivalvia, Euheterodonta, Gastrochaenidae)

    NARCIS (Netherlands)

    Fransen, C.H.J.M.; Meij, van der S.E.T.

    2010-01-01

    During fieldwork in Raja Ampat, West Papua, Indonesia, in 2007, a pontoniine shrimp, most likely belonging to the genus Anchistus, was collected from a coral boring bivalve of the genus Spengleria. This is the first record of a pontoniine shrimp living in association with a boring bivalve. As it

  19. Oral manifestations of patients with lupus erythematosus.

    Science.gov (United States)

    Brennan, Michael T; Valerin, Manuel A; Napeñas, Joel J; Lockhart, Peter B

    2005-01-01

    Lupus erythematosus manifests as cutaneous variants, such as discoid lupus erythematosus or systemic lupus erythematosus. Systemic lupus erythematosus is a multisystem autoimmune disease characterized by general autoantibody production and a wide range of mucocutaneous, renal, neuropsychiatric, cardiovascular, infectious, and hematologic manifestations. This article discusses the prevalence of and considerations for oral mucosal lesions in lupus erythematosus and the impact of the various disease manifestations of systemic lupus erythematosus on dental management.

  20. Ocular manifestations of genetic skin disorders.

    Science.gov (United States)

    Jen, Melinda; Nallasamy, Sudha

    2016-01-01

    Genetic skin diseases, or genodermatoses, often have extracutaneous manifestations. Ocular manifestations in particular can have significant clinical implications, like blindness. Other manifestations, such as the corneal opacities that occur in X-linked ichthyosis, are asymptomatic but characteristic of a particular genodermatosis. Ophthalmologic examination can aid in diagnosis when characteristic findings are seen. The genodermatoses with ocular manifestations will be reviewed, but neurocutaneous, syndromes, genetic pigmentary disorders, and genetic metabolic diseases are not included because they are covered elsewhere in this issue. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Ocular Manifestations of Acquired Immunodeficiency Syndrome.

    Science.gov (United States)

    Kim, Young Shin; Sun, Hae Jung; Kim, Tae Hyong; Kang, Kui Dong; Lee, Sung Jin

    2015-08-01

    To investigate the patterns and risk factors of the ocular manifestations of acquired immunodeficiency syndrome (AIDS) and their correlation with CD4+ count in the era of highly active antiretroviral therapy (HAART). This retrospective study examined 127 AIDS patients who presented to Soonchunhyang University Hospital. Data were collected from patient interviews, clinical examinations, and laboratory investigations. Ophthalmologic examinations included the best-corrected visual acuity, intraocular pressure, anterior segment and adnexal examination, and dilated fundus examination. Of the 127 patients with AIDS, 118 were on HAART and 9 were not. The mean CD4+ count was 266.7 ± 209.1 cells/µL. There were ocular manifestations in 61 patients (48.0%). The incidence of anterior segment manifestations was higher than posterior segment manifestations at 28.3% and 19.7%, respectively. The mean CD4+ count was significantly (p AIDS. In this study, anterior segment and external ocular manifestations occurred more frequently than posterior segment manifestations. Also, the mean CD4+ count was significantly lower in patients with posterior segment ocular manifestations versus anterior segment ocular manifestations. We found that CD4+ count and age >35 years were independent risk factors for developing ocular manifestations.

  2. Adaptive morphologies and guild structure in a high-diversity bivalve fauna from an early Campanian rocky shore, Ivö Klack (Sweden)

    DEFF Research Database (Denmark)

    Sørensen, Anne Mehlin; Surlyk, Finn; Jagt, John W. M.

    2012-01-01

    habitats. Study of the functional morphology of bivalve shells and comparison with extant relatives has resulted in a subdivision of the fauna into seven guilds and five habitats. The bivalve fauna represents a withinhabitat, time-averaged assemblage to which none of the species was introduced from......The bivalve fauna from a late early Campanian rocky shore at Ivö Klack (southern Sweden), comprises just over sixty species, a very high diversity in comparison to other Late Cretaceous and modern rocky shore bivalve assemblages. This high diversity is here considered to represent a reliable census...... of the fauna; only in part can it be explained by the cumulative effect of generations of bivalves inhabiting this coastal environment. The high density and diversity and the wide range of shell morphologies allow interpretation of different modes of life in this variable environment with many contrasting...

  3. Bivalves and Gastropods of the Gulf of Tehuantepec, Mexico: A Checklist of Species with Notes on Their Habitat and Local Distribution

    Directory of Open Access Journals (Sweden)

    Eduardo Ríos-Jara

    2009-01-01

    Full Text Available The taxonomic composition of 160 species of bivalves and gastropods recorded in the Gulf of Tehuantepec is presented with information on their habitat and distribution along 10 different localities of the shoreline and 42 stations of the continental shelf. The species were on sandy and rocky beaches, coastal lagoons, estuaries, mangroves, rocky breakwaters of ports, and shallow subtidal areas (14–47 m depth. A total of 78 bivalve species and 82 gastropod species were recorded. Most of these were associated with sandy and rocky beaches and breakwaters of ports. The estuaries host 30 species and the coastal lagoons only two. In the shallow subtidal there were 18 gastropod species and 40 bivalve species representing 36.3% of all. This study adds 24 bivalve species and 29 gastropod species not recorded in previous studies for a total count of 213 species (102 bivalves and 111 gastropods for Gulf of Tehuantepec.

  4. Electrocardiographic Manifestations of Benzodiazepine Toxicity

    Directory of Open Access Journals (Sweden)

    Nahid Kazemzadeh

    2014-11-01

    Full Text Available Background: The aim of this study was to evaluate and compare the clinical and electrocardiographic (ECG manifestations of benzodiazepines (BZs. Methods: In this retrospective study, all BZ-poisoned patients hospitalized at Loghman Hakim Hospital between September 2010 and March 2011 were evaluated. Patients’ information including age, sex, time elapsed between the ingestion and presentation, and type of the BZ used were extracted from the patients' charts and recorded. ECGs on presentation to the emergency department (ED were evaluated and parameters such as PR interval, QRS duration, corrected QT, amplitude of S wave in lead I, height of R wave and R/S ratio in the lead aVR were also measured and recorded. Results: Oxazepam, chlordiazepoxide, lorazepam, alprazolam, diazepam, and clonazepam were ingested by 9 (3%, 13 (4.4%, 29 (9.9%, 105 (35.8%, 65 (22.2%, and 72 (24.6% patients, respectively. Mean PR interval was reported to be 0.16 ± 0.03 sec and PR interval of greater than 200 msec was detected in 12 (4.5% patients. Mean QRS duration was 0.07 ± 0.01sec and QRS≥120 msec was observed in 7 (2.6% cases. Conclusion: Diazepam is the only BZ that does not cause QRS widening and oxazepam is the only one not causing PR prolongation. It can be concluded that if a patient refers with a decreased level of consciousness and accompanying signs of BZ toxicity, QRS widening in ECG rules out diazepam, whereas PR prolongation rules out oxazepam toxicity.

  5. The radiological manifestation of cryptococcosis

    International Nuclear Information System (INIS)

    Lim, Sue Jin; Oh, Ki Keun

    1980-01-01

    Cryptococcosis is an uncommon mycotic disease caused by Cryptococcosis neoformans, with a special affinity for the respiratory and central nervous system, and less frequently affecting liver, spleen, skin, lymph nodes and kidney. It was first described by Busse in 1984, and since then the occurrences had been world-widely reported with increasing incidence. The outcome of the disease may be fatal when the treatment is delayed. The main portal of entry is via the respiratory tract, and the pulmonary manifestations are not specific but quite varying, that solitary or multiple pulmonary masses, nodular or reticular infiltrations, cavity formation, lymphadenopathy or pleural effusion can be detected on the chest X-ray film simulating many other diseases. Authors analyzed and evaluated 16 cases of confirmed cryptococcosis, and interesting clinical and radiologic features that definitely differed from most of the other reports were notable as follows: 1. The incidence of cryptococcosis ranks 3rd (4.3%) among deep mycoses, next to moniliasis and aspergillosis. 2. 15 of 16 patients are in the period of pediatric age under 16 year old of age. 3. There are no remarkable underlying diseases or predisposing factors encountered in all of the 16 cases. 4. Besides the predominating meningeal irritating symptoms, the involvement of the reticuloendothelial system, l.e., lymph nodes, liver and spleen are notable. 5. Characteristic features of the pulmonary cryptococcosis are: a) 8 of 10 cases have marked hilar and paratracheal lymph nodes enlargement. b) None of the cases reveals solitary pulmonary mass, cavity formation or pleural effusion. c) The lung infiltrations are mainly reticular or coarse nodular pattern. d) The infiltrations s are diffusely distributed on entire lung field, rather than the predilection for the lower lobe. 6. Similarly to most of the other reports, the central nervous system involvement are most frequent (12 of 16 cases). 7. The combined therapy with

  6. Cystic thymic diseases: CT manifestations

    Energy Technology Data Exchange (ETDEWEB)

    Song, Soon Young; Choi, Yo Won; Jeon, Eui Yong; Jeon, Seok Chol; Seo, Heung Suk; Hahm, Chang Kok [School of Medicine, Hanyang University, Seoul (Korea, Republic of)

    1995-09-15

    To describe CT findings and differential points of cystic thymic lesions. We evaluated retrospectively total 19 masses with well marginated cystic lesions at thymic area on CT scans. They were 10 teratomas, 3 congenital thymic cysts, 2 multilocular thymic cysts(associated with thymoma and myasthenia gravis in each), 2 cysts Assciated with thymic Hodgkin's lymphomas an ectopic parathyroid cyst, and an infected thymic cyst. The radiological abnormalities evaluated were thickness of the wall, presence or abscene of septa, mural nodule, solid component, calcification and fat component. All three cases of congenital thymic cysts and an ectopic parathyroid cyst appeared as thin-walled unilocular cyst with homogeneous internal density and without identifiable solid component. In multilocular thymic cyst, there were thick wall and solid components(n =2), thick internal septa and calcifications(n = 1). The cysts of teratomas manifested thick walls(n = 9), internal septa(n = 4), calcifications(n = 6), fat components(n = 4), and solid components(n = 4). Cysts in Hodgkin's diseases appeared as multilocular or unilocular and had thick wall and septa without calcification. Infected thymic cyst presented with multilocular cystic mass with identifiable wall and septa, calcification, and solid components. The thymic diseases with cystic lesion include teratomas, congenital thymic cysts, multilocular thymic cysts, parathyroid cyst, and Hodgkin's disease. Congenital thymic cyst and ectopic parathyroid cyst are thin-walled unilocular cystic lesions. Cystic lesions associated with teratoma, Hodgkin's disease, and multilocular thymic cyst are thick-walled cystic lesions with or without solid component.

  7. Three simple biomarkers useful in conducting water quality assessments with bivalve mollusks.

    Science.gov (United States)

    Blaise, Christian; Gagné, François; Burgeot, Thierry

    2017-12-01

    While biomarkers are undeniably key tools in aquatic ecotoxicology to measure adverse effects linked to contamination events, their application is often inhibited by monetary constraints negating the possibility of having access to dedicated equipment, special wares, and/or expensive reagents. To offset this bottleneck, we propose three simple physiological biomarkers, quantifiable in bivalves, that are free of cost considerations and that can provide basic knowledge on animal health and water quality. Indeed, condition index (CI), growth index (GI), and SOS response (air-time survival) comprise measurements straightforward enough to perform by any laboratory or science body on the planet. Long-term monitoring or screening studies can be carried out with these biomarkers and they are able to provide robust information notably after exposure of bivalves to either singular or multiple agents of contamination. By highlighting examples of data generated in aquatic studies conducted in Eastern Canada under both laboratory and field situations with different species of marine and freshwater mollusks, we establish the suitability of these biomarkers for assessing environmental contamination. Their relationships with other biomarkers are also shown which further corroborate their value as reliable indicators of ecosystem health.

  8. Traces (ichnospecies Oichnus paraboloides of predatory gastropods on bivalve shells from the Seogwipo Formation, Jejudo, Korea

    Directory of Open Access Journals (Sweden)

    Dal-Yong Kong

    2015-12-01

    Full Text Available Circular to subcircular drill holes were identified on the bivalve shells collected from the Seogwipo Formation, Jejudo, Korea. A great majority of the drill holes (>70% were found on the surfaces of a bivalve species Glycymeris rotunda. They are characterized by a beveled sharp edge and paraboloid in cross section with larger outer borehole diameter (OBD; mean 4.21 mm and smaller inner borehole diameter (mean 2.94 mm. Walls of the drill holes are generally smooth, and walls ornamented with etched relief-like structures were also recognized. A slightly raised central boss observed in an incomplete specimen may indicate a failure of predator’s attack. All drill holes collected are classified as a single ichnospecies Oichnus paraboloides Bromley, 1981. They are interpreted as boring traces produced by predatory gastropods, particularly naticid gastropods. Most O. paraboloides boreholes are observed in the central area of shell surfaces; a few boreholes lie marginally, which may reflect a borehole-site selectivity. No correlation between size of prey (shell height and size of predator (OBD is recognized. It is likely, however, that drilled shells of about 30 mm in height represent optimal prey size for naticid predators that lived in a benthic Seogwipo community.

  9. Zoochorous dispersal of freshwater bivalves: an overlooked vector in biological invasions?

    Directory of Open Access Journals (Sweden)

    Coughlan Neil E.

    2017-01-01

    Full Text Available Vectors that underpin the natural dispersal of invasive alien species are frequently unknown. In particular, the passive dispersal (zoochory of one organism (or propagule by another, usually more mobile animal, remains poorly understood. Field observations of the adherence of invasive freshwater bivalves to other organisms have prompted us to assess the importance of zoochory in the spread of three prolific invaders: zebra mussel Dreissena polymorpha; quagga mussel Dreissena bugensis; and Asian clam Corbicula fluminea. An extensive, systematic search of the literature was conducted across multiple on-line scientific databases using various search terms and associated synonyms. In total, only five publications fully satisfied the search criteria. It appears that some fish species can internally transport viable adult D. polymorpha and C. fluminea specimens. Additionally, literature indicates that veligers and juvenile D. polymorpha can adhere to the external surfaces of waterbirds. Overall, literature suggests that zoochorous dispersal of invasive bivalves is possible, but likely a rare occurrence. However, even the establishment of a few individuals (or a single self-fertilising C. fluminea specimen can, over-time, result in a substantial population. Here, we highlight knowledge gaps, identify realistic opportunities for data collection, and suggest management protocols to mitigate the spread of invasive alien species.

  10. Bivalve Omics: State of the Art and Potential Applications for the Biomonitoring of Harmful Marine Compounds

    Directory of Open Access Journals (Sweden)

    Paola Venier

    2013-11-01

    Full Text Available The extraordinary progress experienced by sequencing technologies and bioinformatics has made the development of omic studies virtually ubiquitous in all fields of life sciences nowadays. However, scientific attention has been quite unevenly distributed throughout the different branches of the tree of life, leaving molluscs, one of the most diverse animal groups, relatively unexplored and without representation within the narrow collection of well established model organisms. Within this Phylum, bivalve molluscs play a fundamental role in the functioning of the marine ecosystem, constitute very valuable commercial resources in aquaculture, and have been widely used as sentinel organisms in the biomonitoring of marine pollution. Yet, it has only been very recently that this complex group of organisms became a preferential subject for omic studies, posing new challenges for their integrative characterization. The present contribution aims to give a detailed insight into the state of the art of the omic studies and functional information analysis of bivalve molluscs, providing a timely perspective on the available data resources and on the current and prospective applications for the biomonitoring of harmful marine compounds.

  11. Bivalve omics: state of the art and potential applications for the biomonitoring of harmful marine compounds.

    Science.gov (United States)

    Suárez-Ulloa, Victoria; Fernández-Tajes, Juan; Manfrin, Chiara; Gerdol, Marco; Venier, Paola; Eirín-López, José M

    2013-11-01

    The extraordinary progress experienced by sequencing technologies and bioinformatics has made the development of omic studies virtually ubiquitous in all fields of life sciences nowadays. However, scientific attention has been quite unevenly distributed throughout the different branches of the tree of life, leaving molluscs, one of the most diverse animal groups, relatively unexplored and without representation within the narrow collection of well established model organisms. Within this Phylum, bivalve molluscs play a fundamental role in the functioning of the marine ecosystem, constitute very valuable commercial resources in aquaculture, and have been widely used as sentinel organisms in the biomonitoring of marine pollution. Yet, it has only been very recently that this complex group of organisms became a preferential subject for omic studies, posing new challenges for their integrative characterization. The present contribution aims to give a detailed insight into the state of the art of the omic studies and functional information analysis of bivalve molluscs, providing a timely perspective on the available data resources and on the current and prospective applications for the biomonitoring of harmful marine compounds.

  12. Accumulation of butyl- and phenyltin compounds in starfish and bivalves from the coastal environment of Korea

    International Nuclear Information System (INIS)

    Shim, Won Joon; Yim, Un Hyuk; Kim, Nam Sook; Hong, Sang Hee; Oh, Jae Ryoung; Jeon, Joong Kyun; Okamura, Hideo

    2005-01-01

    Triphenyltin (TPT) and tributyltin (TBT) concentrations were determined in two starfish species (Asteria pectinifera and Asterias amurensis), bivalves (Crassostrea gigas or Mytilus edulis), and seawater samples from sites around the coasts of Korea. Both TPT and TBT concentrations in starfish ranged from 8 to 1560 ng/g and from <2 to 797 ng/g as Sn on a dry weight basis, respectively. TPT concentration accounted for 75.4% and 86.4% of total phenyltin concentration in A. pectinifera and A. amurensis, respectively, while monobutyltin, a degradation product of TBT, accounted for 86.3% and 57.2% of total butyltin, respectively. Triphenyltin concentrations in A. pectinifera were significantly correlated to water and bivalve TPT concentrations, which implies that dietary uptake of TPT from contaminated prey as well as direct uptake from surrounding water contribute to TPT body residues in the starfish. Starfish could be target organisms for monitoring TPT compound in the marine environment, due to their high accumulation and low degradation capacity towards TPT. - Starfish are effective organisms for monitoring phenyltin contamination in the marine environment

  13. Evaluation of the effects of candidate molluscicides on two nontarget bivalves

    Science.gov (United States)

    Waller, D.L.; Marking, L.L.; Rach, J.J.

    1992-01-01

    A variety of molluscicides have been proposed for use in control of zebra mussels (Dreissena polymorpha), but their effect on nontarget aquatic organisms has not been evaluated. Standard methods were adapted for assessing the toxicity of candidate molluscicides to two nontarget bivalves. Fingernail clams, Musculium transversum, and the fawnfoot mussel, Truncilla donaciformis, were selected to represent the two families of native bivalves. Test organisms were collected from pools 6 to 9 of the Upper Mississippi River near La Crosse, WI. Static acute toxicity tests were conducted for 48 hours followed by a 96-hour monitoring period in untreated water to more fully assess survival and mortality. Toxicity data were analyzed by probit analysis to give LC sub(50) values and 95% confidence limits. The same chemicals as those tested at Ohio State University were evaluated against zebra mussels. Results from these studies and those conducted at Ohio State University will be used to evaluate the effectiveness of chemicals in zebra mussel control and their potential hazard to nontarget organisms.

  14. Evaluating Microstructure Preservation using Scanning Electron Microscopy in an Extinct Bivalve, Lahillia larseni

    Science.gov (United States)

    Mohr, R. C.; Tobin, T. S.

    2017-12-01

    Ontogenetic stable isotope (δ18O) sampling of accretionary carbonate shells can provide sub-annual records of environmental conditions, such as seawater temperature, during the life of an organism. These records of seasonal temperature variations can refine our understanding of ancient climates and past climate change. However, because original isotopic signatures can be altered by diagenesis, it is necessary to examine potential specimens for evidence of diagenetic alteration. Abundant aragonitic Lahillia larseni bivalves from the latest Cretaceous and Early Paleogene on Seymour Island, Antarctica, provide excellent opportunities for sclerochronological investigations. Shells of L. larseni preserve clear annual growth bands, which make them ideal candidates for high-resolution δ18O sampling to produce sub-annual records of seawater temperature variation. While the good visual condition of these shells and the preservation of original aragonitic material suggests a high level of preservation suitable for isotopic analysis, subtle alteration of the original shell microstructures can still compromise the original isotopic signatures. Scanning electron microscopy (SEM) can be used to evaluate the preservation of these microstructures. This study compares methods for imaging L. larseni bivalve shells with SEM and seeks a consistent way to evaluate their various microstructures for evidence of diagenetic alteration. High-resolution ontogenetic isotopic sampling will also be conducted on several L. larseni shells, as roughly sinusoidal δ18O profiles are often an indication that the original isotopic signatures have been preserved.

  15. Assessing phototoxicity of petroleum using the bivalve Mulinia lateralis and the mysid Mysidopsis bahia

    International Nuclear Information System (INIS)

    Pelletier, M.; Champlin, D.; Burgess, R.; Ho, K.; Kuhn-Hines, A.

    1995-01-01

    One of the major inputs of PAHs in the marine environment is petroleum products. A large and often catastrophic source of petroleum is an oil spill, which releases concentrated quantities of PAHs into the water column. Intermediate molecular weight compounds remain in the water column for a relatively extended length of time. These compounds include phototoxic PAHs such as anthracene, fluoranthene, pyrene, and their substituted derivatives. Assessments of the environmental impact of marine oil spills have not included phototoxicity tests using pelagic larvae of benthic invertebrates. In this study, the photoreactive toxicity of individual PAHs, including anthracene, pyrene, and fluoranthene, were determined using the bivalve, Mulinia lateralis and the mysid, Mysidopsis bahia. Ultraviolet light exposures increased toxicity relative to fluorescent light for both species but a particularly dramatic response was seen using M. lateralis embryos. This species was relatively insensitive when exposed under fluorescent lights, but exhibited up to a 4,000 fold increase in toxicity under ultraviolet lights. Exposures with different types of petroleum (e.g., fuel oil number-sign 2 and crude oil) under fluorescent and ultraviolet light will demonstrate the utility of this bivalve and mysid for assessing oil spill-related acute and sublethal toxicity in the marine environment

  16. Sodium sulfate impacts feeding, specific dynamic action, and growth rate in the freshwater bivalve Corbicula fluminea.

    Science.gov (United States)

    Soucek, David John

    2007-08-01

    Sodium sulfate is a ubiquitous salt that reaches toxic concentrations due to mining and other industrial activities, yet is currently unregulated at the Federal level in the United States. Previous studies have documented reduced growth of clams downstream of sulfate-dominated effluents, altered bioenergetics in filter-feeding invertebrates, and interactions between sulfate and other toxicants. Therefore, the purpose of this study was to determine if sodium sulfate affects the bioenergetics of the filter-feeding, freshwater bivalve, Corbicula fluminea, and the mechanism by which the effects are elicited. In addition to measuring effects on feeding, respiration and growth rates, I evaluated the relative sensitivity of a green algae consumed by clams to determine if top-down or bottom-up effects might be exhibited under field conditions. This study demonstrated that sodium sulfate had no effect on basal metabolic rates, but significantly reduced the feeding, post-feeding metabolic, and growth rates of C. fluminea. The proposed mechanism for these impacts is that filtering rates are reduced upon exposure, resulting in reduced food consumption and therefore, preventing increased metabolic rates normally associated with post-feeding specific dynamic action (SDA). In the field, these effects may cause changes in whole stream respiration rates and organic matter dynamics, as well as alter uptake rates of other food-associated contaminants like selenium, the toxicity of which is known to be antagonized by sulfate, in filter-feeding bivalves.

  17. Stable oxygen and carbon isotope profiles in an invasive bivalve ( Corbicula fluminea) in North Carolina watersheds

    Science.gov (United States)

    Bucci, John P.; Showers, William J.; Genna, Bernie; Levine, Jay F.

    2009-06-01

    The modern invasive bivalve Corbicula fluminea was collected in 2006 from three sites with different land uses located in a North Carolina River Basin. The primary objective was to describe the δ 18O and δ 13C profiles of C. fluminea shells under various land use conditions. An additional aim was to evaluate whether growth patterns of C. fluminea form seasonally. Annual shell growth patterns were measured from the umbo to the margin and co-varied with estimates of ambient water temperature, corresponding to seasonal variation. The C. fluminea growth patterns as translucent bands (slower growth) appeared to form during winter months and opaque bands (rapid growth) formed during summer. A mixed model analysis (ANOVA) showed a significant site level effect of δ 18O and δ 13C profiles examined among sites ( F = 17.1; p = 0.003). A second model showed a borderline significant site effect among profiles with variability more pronounced at the urban site, Crabtree Creek ( p = 0.085). Previous habitat assessment ratings and water chemistry measurements suggested that the urban site was more impacted by storm water runoff. Understanding δ 18O and δ 13C SHELL profiles and shell growth patterns of the invasive bivalve ( C. fluminea) may help establish a framework for using these animals as biomonitors to record water temperature and nutrient pollution.

  18. Internal distribution of uranium and associated genotoxic damages in the chronically exposed bivalve Corbicula fluminea.

    Science.gov (United States)

    Simon, Olivier; Floriani, Magali; Cavalie, Isabelle; Camilleri, Virginie; Adam, Christelle; Gilbin, Rodolphe; Garnier-Laplace, Jacqueline

    2011-08-01

    Uranium (U) internal distribution and involved effects in the bivalve Corbicula fluminea have been studied after direct chronic exposure (90 d, 10 μg.L-1). U distribution was assessed at the subcellular level (Metal Rich Granules -MRG-, pellets and cytosol fractions) in two main organs of the bivalve (gills and visceral mass). Micro-localisation was investigated by TEM-EDX analysis in the gills epithelium. DNA damage in gill and hemolymph samples was measured by the Comet assay. The 90-d exposure period led to a significant increase of U concentration in gills over time (× 5) and a large U quantity in subcellular granules in gills. Finally, a significant increase (× 2) in DNA damage was noted in exposed gills and haemocytes. This study shows that the accumulation levels and consequently the potential toxicity cannot be successfully predicted only on the basis of concentration in water or in tissues and subcellular fractions after chronic exposure. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Drivers of shell growth of the bivalve, Callista chione (L. 1758) - Combined environmental and biological factors.

    Science.gov (United States)

    Purroy, Ariadna; Milano, Stefania; Schöne, Bernd R; Thébault, Julien; Peharda, Melita

    2018-03-01

    Seasonal shell growth patterns were analyzed using the stable oxygen and carbon isotope values of live-collected specimens of the bivalve Callista chione from two sites in the Adriatic Sea (Pag and Cetina, Croatia). Micromilling was performed on the shell surface of three shells per site and shell oxygen isotopes of the powder samples were measured. The timing and rate of seasonal shell growth was determined by aligning the δ 18 O shell -derived temperatures so that the best fit was achieved with the instrumental temperature curve. According to the data, shells grew only at very low rates or not at all during the winter months, i.e., between January and March. Shell growth slowdown/shutdown temperatures varied among sites, i.e., 13.6 °C at Pag and 16.6 °C at Cetina, indicating that temperature was not the only driver of shell growth. Likely, seasonal differences in seawater temperature and food supply were the major component explaining contrasting growth rates of C. chione at two study sites. Decreasing shell growth rates were also associated with the onset of gametogenesis suggesting a major energy reallocation toward reproduction rather than growth. These results highlight the need to combine sclerochronological analyses with ecological studies to understand life history traits of bivalves as archives of environmental variables. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Contrasting metal detoxification in polychaetes, bivalves and fish from a contaminated bay.

    Science.gov (United States)

    Fan, Wenhong; Xu, Zhizhen; Wang, Wen-Xiong

    2015-02-01

    Jinzhou Bay in Bohai, Northern China, is historically contaminated with metals, but the organisms living in such contaminated environments are much less well studied. In this study, we contrasted the different subcellular and detoxification responses of polychaetes, bivalves and fish collected from different contaminated sites in Jinzhou Bay. In polychaete Neanthes japonica, metal-rich granule (MRG) was the main biologically detoxified metal compartment, and metallothionein-like protein (MTLP) detoxified a relatively smaller fraction of accumulated metals. The importance of MRG increased whereas that of MTLP decreased with increasing metal bioaccumulation. Detoxification in the two bivalves was similar to that in the polychaetes. However, the MRG appeared to play only a minor role in metal binding and detoxification in the gills and livers of fish, whereas MTLP was the dominating detoxification pool. Cellular debris was an important pool binding with metals in the three marine animals. Our study highlighted the contrasting cellular binding and detoxification among different marine organisms living in contaminated environments. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Contamination in sediments, bivalves and sponges of McMurdo Sound, Antarctica

    International Nuclear Information System (INIS)

    Negri, Andrew; Burns, Kathryn; Boyle, Steve; Brinkman, Diane; Webster, Nicole

    2006-01-01

    This study examined the concentrations of total hydrocarbons (THC), polychlorinated biphenyls (PCB), polyaromatic hydrocarbons (PAH), and trace metals (Cu, Zn, Cd, Pb, Hg and As) in marine sediments off Scott Base (NZ) and compared them with sediments near the highly polluted McMurdo Station (US) as well as less impacted sites including Turtle Rock and Cape Evans. The Antarctic mollusc, Laternula elliptica and three common sponge species were also analysed for trace metals. The mean THC concentration in sediments from Scott Base was 3 fold higher than the pristine site, Turtle Rock, but 10 fold lower than samples from McMurdo Station. McMurdo Station sediments also contained the highest concentrations of PAHs, PCBs and the trace metals, Cu, Zn, Pb, Cd and Hg. Copper was significantly higher in bivalves from McMurdo Station than other sites. Trace metal concentrations in sponges were generally consistent within sites but no spatial patterns were apparent. - Analyses of Antarctic marine sediments, bivalves and sponges revealed strong PAH, PCB and trace metal gradients in McMurdo Sound

  2. Immunotoxicity of nanoparticle nTiO2 to a commercial marine bivalve species, Tegillarca granosa.

    Science.gov (United States)

    Shi, Wei; Han, Yu; Guo, Cheng; Zhao, Xinguo; Liu, Saixi; Su, Wenhao; Zha, Shanjie; Wang, Yichen; Liu, Guangxu

    2017-07-01

    The increasing production and extensive application of nanoparticles (NPs) inevitably leads to increased release of NPs into the marine environment and therefore poses a potential threat to marine organisms, especially the sessile benthic bivalves. However, the impacts of NPs on the immunity of commercial and ecological important bivalve species, Tegillarca granosa, still remain unknown to date. In addition, the molecular mechanism of the immunotoxicity of NPs still remains unclear in marine invertebrates. Therefore, the immunotoxicity of nTiO 2 exposure to T. granosa at environmental realistic concentrations was investigated in the present study. Results obtained showed that the total number, phagocytic activity, and red granulocytes ratio of the haemocytes were significantly reduced after 30 days nTiO 2 exposures at the concentrations of 10 and 100 μg/L. Furthermore, the expressions of genes encoding Pattern Recognition Receptors (PPRs) and downstream immune-related molecules were significantly down-regulated by nTiO 2 exposures, indicating a reduced sensitivity to pathogen challenges. In conclusion, evident immunotoxicity of nTiO 2 to T. granosa at environmental realistic concentrations was detected by the present study. In addition, the gene expression analysis suggests that the PRRs (both TLRs and RIG1 investigated) may be the molecules for NPs recognition in marine invertebrates. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Inducing the Alternative Oxidase Forms Part of the Molecular Strategy of Anoxic Survival in Freshwater Bivalves

    Directory of Open Access Journals (Sweden)

    Maria S. Yusseppone

    2018-02-01

    Full Text Available Hypoxia in freshwater ecosystems is spreading as a consequence of global change, including pollution and eutrophication. In the Patagonian Andes, a decline in precipitation causes reduced lake water volumes and stagnant conditions that limit oxygen transport and exacerbate hypoxia below the upper mixed layer. We analyzed the molecular and biochemical response of the North Patagonian bivalve Diplodon chilensis after 10 days of experimental anoxia (<0.2 mg O2/L, hypoxia (2 mg O2/L, and normoxia (9 mg O2/L. Specifically, we investigated the expression of an alternative oxidase (AOX pathway assumed to shortcut the regular mitochondrial electron transport system (ETS during metabolic rate depression (MRD in hypoxia-tolerant invertebrates. Whereas, the AOX system was strongly upregulated during anoxia in gills, ETS activities and energy mobilization decreased [less transcription of glycogen phosphorylase (GlyP and succinate dehydrogenase (SDH in gills and mantle]. Accumulation of succinate and induction of malate dehydrogenase (MDH activity could indicate activation of anaerobic mitochondrial pathways to support anoxic survival in D. chilensis. Oxidative stress [protein carbonylation, glutathione peroxidase (GPx expression] and apoptotic intensity (caspase 3/7 activity decreased, whereas an unfolded protein response (HSP90 was induced under anoxia. This is the first clear evidence of the concerted regulation of the AOX and ETS genes in a hypoxia-tolerant freshwater bivalve and yet another example that exposure to hypoxia and anoxia is not necessarily accompanied by oxidative stress in hypoxia-tolerant mollusks.

  4. Oral manifestations of syphilis: a review

    Directory of Open Access Journals (Sweden)

    A.B. Soares

    2004-01-01

    Full Text Available Syphilis is an infectious disease presenting stages associated with specific oral lesions. Therefore, health professionals should be familiar with the different syphilis oral manifestations at each stage and be prepared to refer any suspected patient for further evaluation. This report describes the most important clinical factors of each stage, emphasizing the oral manifestations.

  5. Effects of Onchocerciasis Manifestations on Academic Performance ...

    African Journals Online (AJOL)

    A study of the effects of various manifestations of onchocerciasis namely visual impairment, oncho-rashes (papular oncodermatitis) and palpable nodules on academic performance was undertaken with the objective of finding out the manifestation with the most serious negative effect on academic performance. The study ...

  6. Congenital rubella syndrome and delayed manifestations

    DEFF Research Database (Denmark)

    Dammeyer, Jesper Herup

    2010-01-01

    Objective: Several hypotheses of different medical and psychological delayed manifestations among people who have congenital rubella syndrome (CRS) have been discussed. This study tests some of these hypotheses of delayed manifestations. Methods: Gathering information about 35 individuals who have...

  7. Unusual Cutaneous Manifestation of Tuberous Sclerosis

    Directory of Open Access Journals (Sweden)

    K C Shah

    1980-01-01

    Full Text Available Cutaneous manifestations are found in 60 to 70% cases of tuberous sclerosis and consist of adenoma sebaceum, periungual fibromatas, cafe au lait spots, shagreen patches and white macules. Our patient showed unusual skin manifestations like spotty pigmentation on the chest, back and abdomen and hyperkeratosis palmaris et plantaris.

  8. Congenital rubella syndrome and delayed manifestations

    DEFF Research Database (Denmark)

    Dammeyer, Jesper Herup

    2010-01-01

    Objective: Several hypotheses of different medical and psychological delayed manifestations among people who have congenital rubella syndrome (CRS) have been discussed. This study tests some of these hypotheses of delayed manifestations. Methods: Gathering information about 35 individuals who hav...... which people with CRS face must primarily be understood in relation to congenital deafblindness and dual sensory and communicative deprivation....

  9. Manifestation Determination: Rulings of the Courts

    Science.gov (United States)

    Zilz, Walter A.

    2006-01-01

    A legal history of the logic behind the manifestation determination meeting was compiled based on a review of the literature. In addition a search of the Individuals with Disabilities Education law Reporter (IDELR) was conducted to identify manifestation determination cases decided after 1994 and before 2003. This time frame gave an indication of…

  10. Variation of the physiological energetics of the bivalve Spisula subtruncata (da Costa, 1778) within an annual cycle

    NARCIS (Netherlands)

    Rueda, J.L.; Smaal, A.C.

    2004-01-01

    Spisula subtruncata is an infaunal filter-feeding bivalve, which lives in shallow sandy bottoms (2¿20 m depth) from Norway to the Atlantic coasts of Morocco, including the Mediterranean Sea. Considering that fisheries of this species have become an important economic resource in some European

  11. Occurrence of pharmaceuticals and endocrine disrupting compounds in macroalgaes, bivalves, and fish from coastal areas in Europe

    NARCIS (Netherlands)

    Álvarez-Muñoz, D.; Rodríguez-Mozaz, S.; Maulvault, A.L.; Tediosi, A.; Fernández-Tejedor, M.; Heuvel, Van den F.; Kotterman, M.; Marques, A.; Barceló, D.

    2015-01-01

    The ocurrence and levels of PhACs, Endocrine Disrupting and related Compounds (EDCs) in seafood from potential contaminated areas in Europe has been studied. Macroalgae (S. accharina latissima and Laminaria digitata), bivalves (Mytilus galloprovincialis, Mytilus spp., Chamalea gallina and

  12. Spatial intertidal distribution of bivalves and polychaetes in relation to environmental conditions in the Natori River estuary, Japan

    Science.gov (United States)

    Tomiyama, Takeshi; Komizunai, Nobuhiro; Shirase, Tatsuya; Ito, Kinuko; Omori, Michio

    2008-11-01

    This paper aims to reveal spatial variation in the abundance of infaunal bivalves and polychaetes at different spatial scales (station: 200-800 m intervals; plot: 5-20 m), and to reveal environmental variables affecting the spatial distribution of animals in the Natori River estuary, Japan. We found six bivalve species and eight polychaete species from 52 plots at 12 stations. Nuttallia olivacea and Heteromastus sp. were found to be the most abundant species of bivalves and polychaetes, respectively. Assemblage patterns of bivalves and polychaetes were classified into five distinct groups. Substrata (silt-clay contents), salinity, and relative elevation were the variables found to affect the infaunal assemblage patterns. Chlorophyll a was not a significant variable, but benthic animals were absent at sites with extremely low chlorophyll a conditions. Macrobenthic assemblage patterns were different not only between stations but often differed between plots at the same station, reflecting the complex assemblage structure of benthic invertebrates. Detailing such animal-environment relationship is essential in understanding the potential food supply for estuarine fishes.

  13. Uniform Variation in Genetic-Traits of a Marine Bivalve Related to Starvation, Pollution and Geographic Clines

    NARCIS (Netherlands)

    Hummel, H.; Bogaards, R.H.; Amiard-Triquet, C.; Bachelet, G.; Desprez, M.; Marchand, J.; Rybarczyk, H.; Sylvand, B.; De Wit, Y.; De Wolf, L.

    1995-01-01

    Consistent patterns of genetic variation in the marine bivalve Macoma balthica (L.) were found after exposure to low levels of copper, starvation, and along geographic dines. The geographic dines were related to temperature and salinity. Genetic differences were primarily found in the LAP (Leucine

  14. Disjunct distribution of highly diverged mitochondrial lineage clade and population subdivision in a marine bivalve with pelagic larval dispersal

    NARCIS (Netherlands)

    Luttikhuizen, PC; Drent, J; Baker, AJ

    Mitochondrial DNA sequence data for 295 individuals of the marine bivalve Macoma balthica (L.) were collected from 10 sites across the European distribution, and from Alaska. The data were used to infer population subdivision history and estimate current levels of gene flow. Inferred historical

  15. ESTIMATING THE DISTRIBUTION OF HARVESTED ESTUARINE BIVALVES WITH HABITAT SUITABILITY MODELS AND UNDERSTANDING THE IMPLICATIONS UNDER A CHANGING CLIMATE

    Science.gov (United States)

    Habitat suitability models are useful to forecast how environmental change may affect the abundance or distribution of species of interest. In the case of harvested bivalves, those models may be used to estimate the vulnerability of this valued ecosystem good to stressors. Usin...

  16. Genotoxic and cytotoxic effects on the immune cells of the freshwater bivalve Dreissena polymorpha exposed to the environmental neurotoxin BMAA

    NARCIS (Netherlands)

    Lepoutre, Alexandra; Milliote, Nadia; Bonnard, Marc; Palos-Ladeiro, Mélissa; Rioult, Damien; Bonnard, Isabelle; Bastien, Fanny; Faassen, Elisabeth; Geffard, Alain; Lance, Emilie

    2018-01-01

    The environmental neurotoxin β-N-Methylamino-L-alanine (BMAA) has been pointed out to be involved in human neurodegenerative diseases. This molecule is known to be bioaccumulated by bivalves. However, little data about its toxic effects on freshwater mussels is available, particularly on the

  17. The vertical distribution and abundance of gastropods and bivalves from rocky beaches of Cuastecomate Bay, Jalisco, México.

    Science.gov (United States)

    Esqueda, M C; Ríos-Jara, E; Michel-Morfín, J E; Landa-Jaime, V

    2000-12-01

    The vertical distribution and abundance of conspicuous gastropod and bivalve species were studied at five rocky beaches in Cuastecomate Bay, Jalisco. Sampling was done from September, 1993 through March, 1994 with 0.75 m2 quadrants placed along replicate transect lines (10 m long) in the supralittoral and mesolittoral (upper, middle and lower intertidal) zones. A total of 6,643 mollusks were collected. Gastropods dominated the samples (6,272 individuals, 44 species); the bivalves were less abundant and diverse (371 individuals, five species). Seventeen species comprised 89.8% of all individuals collected. The gastropods Nodilittorina aspera and Nerita scabricosta were the most abundant with 637.8 and 71.43 individuals/m2, respectively. The most abundant bivalves were Brachidontes adamsianus and Chloromytilus palliopunctatus with 60.7 and 61.3 individuals/m2 respectively. The abundance of gastropods decreased from the supralittoral to the lower tidal zones while the number of species increased in the same direction. The number of species of bivalves also increased from the supralittoral to the lower intertidal zone; the abundance of individuals was higher at the middle intertidal zone. Affinities between groups of species among sampling stations were identified by computing Pearson's correlation coefficient using abundance values (ind./m2) and Jaccard's dissimilarity index using species presence or absence in the lower intertidal zone. Affinity among stations was not dependent upon their vicinity but on the high dominance of few species, the occurrence of many secondary species and beach characteristics.

  18. Assessment of Heavy Metals in Bivalves Molluscs of Apulian Region: a 3-years control activity of a EU Laboratory

    Directory of Open Access Journals (Sweden)

    Miedico O.

    2013-04-01

    Full Text Available The bivalve molluscs represent an important matrix to be studied for several reasons. Their nutritional properties make them valuable to the consumers, so that their consumption and commercial value has risen worldwide. Simultaneously, their significant water-filtering capability and their persistence in the same place make them good bio-indicators of marine ecosystems. The presence of the heavy metal contaminants, as Cd, Pb and Hg, was investigated in bivalve molluscs such as mussels (Mytilus galloprovincialis, clams (Venus gallina and oysters (Ostrea edulis. In the present study, a survey was carried out on 334 samples addressed to the Istituto Zooprofilattico Sperimentale – Puglia e Basilicata, Foggia (ITALY between 2009-2011, and collected by official authorities along the coasts of Apulia Region. The conformity of heavy metal content in bivalve molluscs was verified, in according to EC Reg. 1881/2006. The compliance was found for the total amount of samples. The obtained data on heavy metals concentration in bivalve molluscs were compared with data found in monitoring studies on the incidence of heavy metals in 1981 in North-Western Mediterranean Sea, in 2003 in Tyrrhenian Sea and in 2010 in Pacific Ocean (Chile, reported in literature. The information obtained from this work offer an essential database, not only for the authorities involved in food control, but also for the official institutions responsible of a constant control of the marine ecosystem pollution.

  19. [Detection of norovirus RNA in bivalve molluscs by using bacteria-culture-employed method (A3T method)].

    Science.gov (United States)

    Akiba, Tetsuya; Tanaka, Tatsuya; Nagano, Miyuki; Mori, Kohji; Hayashi, Yukinao; Obata, Hiromi; Chiba, Takashi; Ikuta, Yasuhisa; Kamiya, Yoriko; Nakama, Akiko; Hosaka, Mitsugu; Kai, Akemi

    2010-01-01

    Norovirus (NV) RNA has rarely been detected in foods despite the use of highly sensitive methods such as RT-PCR and real-time RT-PCR. In the modified method (A3T method) reported previously, a bacterial culture process was introduced into the standard protocol for NV detection to remove some inhibitor(s) present in food ingredients. To confirm the efficiency of the A3T method and to examine NV contamination in bivalve molluscs, we tried to detect NV RNA in bivalve molluscs on the market and in oyster samples associated with foodborne outbreaks by using the standard method and the A3T method. NV RNAs were detected in 20 samples (18.0%) of 111 bivalve molluscs, including oysters, on the market by use of the A3T method, while only one sample (0.9%) was positive according to the standard method. NV RNA was also detected in 10 of 35 oyster samples related to foodborne outbreaks by the A3T method. Those results show that the A3T method is suitable for the detection of NV in bivalve molluscs in general laboratories.

  20. Contrasting behavioral and feeding strategies recorded by tidal-flat bivalve trace fossils from the Upper Carboniferous of eastern Kansas

    Science.gov (United States)

    Mangano, M.G.; Buatois, L.A.; West, R.R.; Maples, C.G.

    1998-01-01

    Upper Carboniferous tidal-flat deposits near Waverly, eastern Kansas (Stull Shale Member, Kanwaka Shale Formation), host abundant and very well-preserved trace fossils attributed to the activity of burrowing bivalves. Thin shell lenses with an abundant bivalve fauna area associated with the ichnofossil-bearing beds and afford an unusual opportunity to relate trace fossils to their makers. Two distinctive life and feeding strategies can be reconstructed on the basis of trace fossil analysis and functional morphology. Lockeria siliquaria hyporeliefs commonly are connected with vertical to inclined, truncated endichnial shafts in the absence of horizontal locomotion traces. These structures record vertical and oblique displacement through the sediment, and suggest relatively stable domiciles rather than temporary resting traces as typically considered. Crowded bedding surfaces displaying cross-cutting relationships between specimens of L. siliquaria and differential preservation at the top (concave versus convex epireliefs) record a complex history of successive events of colonization, erosion, deposition, and recolonization (time-averaged assemblages). Irregujlar contours of some large hypichnia indicate the cast of the foot, while other outlines closely match the anterior area of Wilkingia, its suggested tracemaker. Relatively stable, vertical to inclined life positions and dominanit vertical mobility suggest a filter-feeding strategy. Moreover, the elongate shell and pallial sinus of Wilkingia providfe a strong independent line of evidence for an opisthosiphonate, moderately deep-tier inhabitant. Wilingia may represent a pioneer attempt at siphon-feeding in the late Paleozoic, preceding the outcome of the Mesozoic infaunal radiation. A second strategy is represented by Lockeia ornata and association locomotionm and locomotion/feding structures. Lockeia ornata is commonly connected with chevron locomotion traces that record the bifurcated foot of a protobranch

  1. Neurological Manifestations In Inflammatory Bowel Disease

    Directory of Open Access Journals (Sweden)

    youssef HNACH

    2015-06-01

    Full Text Available IntroductionThe purpose of this retrospective study was to report neurological manifestations noted in patients who were monitored for inflammatory bowel disease, in order to document the pathophysiological, clinical, progressive, and therapeutic characteristics of this entity.Material and methodsWe conducted a retrospective study on patients monitored -in the gastroenterology service in Ibn Sina Hospital in Rabat, Morocco- for inflammatory bowel disease from 1992 till 2013 and who developed neurological manifestations during its course. Patients with iatrogenic complications were excluded, as well as patients with cerebrovascular risk factors.ResultsThere were 6 patients, 4 of whom have developed peripheral manifestations. Electromyography enabled the diagnosis to be made and the outcome was favorable with disappearance of clinical manifestations and normalization of the electromyography.The other 2 patients, monitored for Crohn’s disease, developed ischemic stroke. Cerebral computed tomography angiography provided positive and topographic diagnosis. Two patients were admitted to specialized facilities.ConclusionNeurological manifestations in inflammatory bowel disease are rarely reported.  Peripheral neuropathies and stroke remain the most common manifestations. The mechanisms of these manifestations are not clearly defined yet. Currently, we hypothesize the interaction of immune mediators.

  2. Differential protein expression in two bivalve species; Mytilus galloprovincialis and Corbicula fluminea; exposed to Cylindrospermopsis raciborskii cells.

    Science.gov (United States)

    Puerto, Maria; Campos, Alexandre; Prieto, Ana; Cameán, Ana; de Almeida, André Martinho; Coelho, Ana Varela; Vasconcelos, Vitor

    2011-01-17

    The cyanobacteria Cylindrospermopsis raciborskii is considered a threat to aquatic organisms due to the production of the toxin cylindrospermopsin (CYN). Despite the numerous reports evidencing the toxic effects of C. raciborskii cells and CYN in different species, not much is known regarding the toxicity mechanisms associated with this toxin and the cyanobacteria. In this work, a proteomics approach based in the two-dimensional gel electrophoresis and mass spectrometry was used to study the effects of the exposure of two bivalve species, Mytilus galloprovincialis and Corbicula fluminea, to CYN producing (CYN+) and non-producing (CYN-) C. raciborskii cells. Additionally the activities of glutathione S-transferase (GST) and glutathione peroxidase (GPx) were determined. Alterations in actin and tubulin isoforms were detected in gills of both bivalve species and digestive gland of M. galloprovincialis when exposed to CYN- and CYN+ cells. Moreover, GST and GPx activities changed in gills and digestive tract of bivalves exposed to both C. raciborskii freeze dried cells, in comparison to control animals exposed to the green alga Chlorella vulgaris. These results suggest the induction of physiological stress and tissue injury in bivalves by C. raciborskii. This condition is supported by the changes observed in GPx and GST activities which indicate alterations in the oxidative stress defense mechanisms. The results also evidence the capacity of CYN non-producing C. raciborskii to induce biochemical responses and therefore its toxicity potential to bivalves. The heat shock protein 60 (HSP60), extrapallial (EP) fluid protein and triosephosphate isomerase homologous proteins from gills of M. galloprovincialis were down-regulated specifically with the presence of CYN+ C. raciborskii cells. The presence of CYN may lead to additional toxic effects in M. galloprovincialis. This work demonstrates that proteomics is a powerful approach to characterize the biochemical effects of C

  3. Biologically induced deposition of fine suspended particles by filter-feeding bivalves in land-based industrial marine aquaculture wastewater.

    Directory of Open Access Journals (Sweden)

    Yi Zhou

    Full Text Available Industrial aquaculture wastewater contains large quantities of suspended particles that can be easily broken down physically. Introduction of macro-bio-filters, such as bivalve filter feeders, may offer the potential for treatment of fine suspended matter in industrial aquaculture wastewater. In this study, we employed two kinds of bivalve filter feeders, the Pacific oyster Crassostrea gigas and the blue mussel Mytilus galloprovincialis, to deposit suspended solids from marine fish aquaculture wastewater in flow-through systems. Results showed that the biodeposition rate of suspended particles by C. gigas (shell height: 8.67 ± 0.99 cm and M. galloprovincialis (shell height: 4.43 ± 0.98 cm was 77.84 ± 7.77 and 6.37 ± 0.67 mg ind(-1 • d(-1, respectively. The total solid suspension (TSS deposition rates of oyster and mussel treatments were 3.73 ± 0.27 and 2.76 ± 0.20 times higher than that of the control treatment without bivalves, respectively. The TSS deposition rates of bivalve treatments were significantly higher than the natural sedimentation rate of the control treatment (P < 0.001. Furthermore, organic matter and C, N in the sediments of bivalve treatments were significantly lower than those in the sediments of the control (P < 0.05. It was suggested that the filter feeders C. gigas and M. galloprovincialis had considerable potential to filter and accelerate the deposition of suspended particles from industrial aquaculture wastewater, and simultaneously yield value-added biological products.

  4. Wegener Granulomatosis: Otologic Manifestation as First Symptom.

    Science.gov (United States)

    Costa, Carla Fabiane da; Polanski, Jose Fernando

    2015-07-01

    Introduction Wegener granulomatosis is a systemic vasculitis affecting small and medium-sized vessels of the upper and lower respiratory tract and kidneys. Objective To describe a case of Wegener disease with atypical manifestation. Resumed Report We describe the case of a 50-year-old woman with chronic otitis media and sensorineural hearing loss as the primary symptoms, without other manifestations. Conclusion In cases of acute ear manifestations with or without hearing loss and with poor response to usual treatments, Wegener granulomatosis should be included among the possible etiologies. After adequate diagnoses and treatment of this rare disease, there was favorable evolution.

  5. Wegener Granulomatosis: Otologic Manifestation as First Symptom

    Directory of Open Access Journals (Sweden)

    Costa, Carla Fabiane da

    2014-11-01

    Full Text Available Introduction Wegener granulomatosis is a systemic vasculitis affecting small and medium-sized vessels of the upper and lower respiratory tract and kidneys. Objective To describe a case of Wegener disease with atypical manifestation. Resumed Report We describe the case of a 50-year-old woman with chronic otitis media and sensorineural hearing loss as the primary symptoms, without other manifestations. Conclusion In cases of acute ear manifestations with or without hearing loss and with poor response to usual treatments, Wegener granulomatosis should be included among the possible etiologies. After adequate diagnoses and treatment of this rare disease, there was favorable evolution.

  6. Genetic alterations in syndromes with oral manifestations

    Directory of Open Access Journals (Sweden)

    Krishnamurthy Anuthama

    2013-01-01

    Full Text Available Ever since Gregor Johan Mendel proposed the law of inheritance, genetics has transcended the field of health and has entered all walks of life in its application. Thus, the gene is the pivoting factor for all happenings revolving around it. Knowledge of gene mapping in various diseases would be a valuable tool in prenatally diagnosing the condition and averting the future disability and stigma for the posterity. This article includes an array of genetically determined conditions in patients seen at our college out-patient department with complete manifestation, partial manifestation and array of manifestations not fitting into a particular syndrome.

  7. Genetic alterations in syndromes with oral manifestations.

    Science.gov (United States)

    Anuthama, Krishnamurthy; Prasad, Harikrishnan; Ramani, Pratibha; Premkumar, Priya; Natesan, Anuja; Sherlin, Herald J

    2013-11-01

    Ever since Gregor Johan Mendel proposed the law of inheritance, genetics has transcended the field of health and has entered all walks of life in its application. Thus, the gene is the pivoting factor for all happenings revolving around it. Knowledge of gene mapping in various diseases would be a valuable tool in prenatally diagnosing the condition and averting the future disability and stigma for the posterity. This article includes an array of genetically determined conditions in patients seen at our college out-patient department with complete manifestation, partial manifestation and array of manifestations not fitting into a particular syndrome.

  8. Chemical composition of two mineralogically contrasting Arctic bivalves' shells and their relationships to environmental variables.

    Science.gov (United States)

    Iglikowska, A; Bełdowski, J; Chełchowski, M; Chierici, M; Kędra, M; Przytarska, J; Sowa, A; Kukliński, P

    2017-01-30

    The main goal of this study was to determine the concentrations of trace elements in the mineralogically contrasting shells of two Arctic bivalves: Chlamys islandica and Ciliatocardium ciliatum. Aragonite shells seem to be more susceptible to the binding of metal ions, which is most likely a result of their crystal lattice structure. We suggest that less biologically controlled aragonite mineralization tends to incorporate more metal impurities into the crystal lattice in waters with a lower pH, where metal ions are more available. Higher concentrations of impurities may further increase the lattice distortion causing lower crystal lattice stability and higher susceptibility to dissolution. Calcitic shells seem to be less prone to bind metal ions than aragonite shells most likely because under strict biological control, the uptake of ions from ambient seawater is more selective; thus, the final crystal lattice is less contaminated by other metals and is more resistant to dissolution. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Uptake and metabolism of 14C-chloropyrifos by marine bivalves

    International Nuclear Information System (INIS)

    Zhong, C.G.; Chen, S.; Zhao, X.; Shi, J.; Carvalho, F.P.

    1999-01-01

    The uptake and metabolism of 14 C-chlorpyrifos by two marine bivalves, Paphia undulata and Sinonovacula constricta, were studied in a simulated ecosystem. The experiments were carried out in two 30 L glass tanks containing each 20 L of filtered sea water, contaminated with 14 C-chlorpyrifos 1.85x10 4 Bq.L -1 (16.7 μg.L -1 ) at the beginning of the exposure period. At different time intervals, three specimens of each species were sampled for analysis of the pesticide in the molluscs tissues. The 14 C-chlorpyrifos residues were extracted from the digestive gland of the molluscs and analyzed by co-chromatography with pesticide standards by TLC methods described before

  10. Accumulation, elimination and chemical speciation of mercury in the bivalves Mytilus edulis and Macoma balthica

    DEFF Research Database (Denmark)

    Riisgård, H. U.; Kiørboe, Thomas; Møhlenberg, F.

    1985-01-01

    Mussels (Mytilus edulis) transferred in net bags from clean to chronically mercury polluted water readily accumulated mercury during an exposure period of three months. Growth of the transplanted mussels had a “diluting” effect on the mercury concentration, but the absolute weight of mercury uptake...... for M. edulis from the chronically polluted area in contrast to only 53 d for mussels from a temporary massive mercury polluted area near a chemical deposit. In both cases about 75% of the total mercury in the mussels was inorganic, and it is suggested that both inorganic and organic mercury species...... were immobilized in mussels from the long-term mercury polluted area, whereas the immobilization capacity was exceeded in the short-term mercury exposed mussels near the chemical deposit. Very slow elimination of mercury was observed in the deposit-feeding bivalve Macoma balthica from the chronically...

  11. Musculoskeletal manifestations of the antiphospholipid syndrome.

    Science.gov (United States)

    Noureldine, M H A; Khamashta, M A; Merashli, M; Sabbouh, T; Hughes, G R V; Uthman, I

    2016-04-01

    The scope of clinical and laboratory manifestations of the antiphospholipid syndrome (APS) has increased dramatically since its discovery in 1983, where any organ system can be involved. Musculoskeletal complications are consistently reported in APS patients, not only causing morbidity and mortality, but also affecting their quality of life. We reviewed all English papers on APS involvement in the musculoskeletal system using Google Scholar and Pubmed; all reports are summarized in a table in this review. The spectrum of manifestations includes arthralgia/arthritis, avascular necrosis of bone, bone marrow necrosis, complex regional pain syndrome type-1, muscle infarction, non-traumatic fractures, and osteoporosis. Some of these manifestations were reported in good quality studies, some of which showed an association between aPL-positivity and the occurrence of these manifestations, while others were merely described in case reports. © The Author(s) 2016.

  12. Endocrine disorders and the neurologic manifestations

    Directory of Open Access Journals (Sweden)

    Jeesuk Yu

    2014-12-01

    Full Text Available The nervous system and the endocrine system are closely interrelated and both involved intimately in maintaining homeostasis. Endocrine dysfunctions may lead to various neurologic manifestations such as headache, myopathy, and acute encephalopathy including coma. It is important to recognize the neurologic signs and symptoms caused by the endocrine disorders while managing endocrine disorders. This article provides an overview of the neurologic manifestations found in various endocrine disorders that affect pediatric patients. It is valuable to think about 'endocrine disorder' as a cause of the neurologic manifestations. Early diagnosis and treatment of hormonal imbalance can rapidly relieve the neurologic symptoms. Better understanding of the interaction between the endocrine system and the nervous system, combined with the knowledge about the pathophysiology of the neurologic manifestations presented in the endocrine disorders might allow earlier diagnosis and better treatment of the endocrine disorders.

  13. Manifest toob klassika taas kinoekraanile / Andri Maimets

    Index Scriptorium Estoniae

    Maimets, Andri, 1979-

    2007-01-01

    2.-9. veebr. on kinos "Sõprus" ja 11.-15. veebr. Tartu Sadamateatris 5. kultusfilmide festival Manifest, seekord USA filmid ja teemaks sõnavabadus. Esilinastub ka Urmas E. Liivi dokumentaalfilm "Tervitusi Nõukogude Eestist!"

  14. Cutaneous manifestations in patients with mastocytosis

    DEFF Research Database (Denmark)

    Hartmann, Karin; Escribano, Luis; Grattan, Clive

    2016-01-01

    Cutaneous lesions in patients with mastocytosis are highly heterogeneous and encompass localized and disseminated forms. Although a classification and criteria for cutaneous mastocytosis (CM) have been proposed, there remains a need to better define subforms of cutaneous manifestations in patient...

  15. Broken Chains: The Effect of Ocean Acidification on Bivalve and Echinoid Development

    Science.gov (United States)

    Richardson, K.

    2016-12-01

    Global warming is one of the most urgent issues facing the interconnected systems of our planet. One important impact of global warming is ocean acidification, which is a change in the pH of the oceans due to increased levels of carbon dioxide in the atmosphere. This can harm ocean life in many ways, including the disintegration of reef structures and the weakening of many types of sea animals' shells. The purpose of this project is to assess the efficacy of a novel method of raising the pH of increasingly acidic ocean waters. The experiment was set up with water of varying pH levels. There were three different experiment groups, including current ocean water (pH 8.1), increased acidity ocean water (pH 7.5), and an increased acidity ocean water with an activated carbon filter (pH 7.5). Six bivalve shells were placed in each solution . Mass loss data was taken from bivalve shells every three days over the course of thirty days (for a total of ten measurements). I hypothesized that the carbon filter would improve the pH of the ocean water (by raising the pH from 7.5) to that of normal ocean water (pH 8.1). The data showed that while the acidic ocean water shell's weight decreased (by 13%), the acidic water with the filter and current ocean water decreased by 0.3% and 0.5%, respectively. Overall, the activated carbon filter decreased the amount of weight change from the acidic water. The data is applicable to helping solve ocean acidification - activated charcoal greatly improved the effects of very acidic ocean water, which could be used in the future to help offset the impact of ocean acidification on its creatures.

  16. Impact of seawater carbonate chemistry on the calcification of marine bivalves

    Science.gov (United States)

    Thomsen, J.; Haynert, K.; Wegner, K. M.; Melzner, F.

    2015-07-01

    Bivalve calcification, particularly of the early larval stages, is highly sensitive to the change in ocean carbonate chemistry resulting from atmospheric CO2 uptake. Earlier studies suggested that declining seawater [CO32-] and thereby lowered carbonate saturation affect shell production. However, disturbances of physiological processes such as acid-base regulation by adverse seawater pCO2 and pH can affect calcification in a secondary fashion. In order to determine the exact carbonate system component by which growth and calcification are affected it is necessary to utilize more complex carbonate chemistry manipulations. As single factors, pCO2 had no effects and [HCO3-] and pH had only limited effects on shell growth, while lowered [CO32-] strongly impacted calcification. Dissolved inorganic carbon (CT) limiting conditions led to strong reductions in calcification, despite high [CO32-], indicating that [HCO3-] rather than [CO32-] is the inorganic carbon source utilized for calcification by mytilid mussels. However, as the ratio [HCO3-] / [H+] is linearly correlated with [CO32-] it is not possible to differentiate between these under natural seawater conditions. An equivalent of about 80 μmol kg-1 [CO32-] is required to saturate inorganic carbon supply for calcification in bivalves. Below this threshold biomineralization rates rapidly decline. A comparison of literature data available for larvae and juvenile mussels and oysters originating from habitats differing substantially with respect to prevailing carbonate chemistry conditions revealed similar response curves. This suggests that the mechanisms which determine sensitivity of calcification in this group are highly conserved. The higher sensitivity of larval calcification seems to primarily result from the much higher relative calcification rates in early life stages. In order to reveal and understand the mechanisms that limit or facilitate adaptation to future ocean acidification, it is necessary to better

  17. Occurrence and Trend of Hepatitis A Virus in Bivalve Molluscs Production Areas Following a Contamination Event.

    Science.gov (United States)

    Suffredini, Elisabetta; Proroga, Yolande Thérèse Rose; Di Pasquale, Simona; Di Maro, Orlandina; Losardo, Maria; Cozzi, Loredana; Capuano, Federico; De Medici, Dario

    2017-12-01

    The aim of this study was to assess the trend of hepatitis A virus (HAV) in a coastal zone impacted by a contamination event, providing data for the development of management strategies. A total of 352 samples, including four bivalve mollusc species (Mytilus galloprovincialis, Solen vagina, Venus gallina and Donax trunculus), were taken over a period of 6 months from 27 production areas of the coast and analysis were performed according to ISO/TS 15216-1:2013. HAV presence was detected in 77 samples from 11 production areas and all positive results were related to samples collected in the first 3 months of the surveillance, during which HAV prevalence was 39.9% and values as high as 5096 genome copies/g were detected. A progressive reduction of viral contamination was evident during the first trimester of the monitoring, with prevalence decreasing from 78.8% in the first month, to 37.8% in the second and 3.9% in the third and quantitative levels reduced from an average value of 672 genome copies/g to 255 genome copies/g over a period of 4 weeks (virus half-life: 21.5 days). A regression analysis showed that, during the decreasing phase of the contamination, the data fitted a reciprocal quadratic model (Ra 2  = 0.921) and, based on the model, a residual presence of HAV could be estimated after negativization of the production areas. The statistical analysis of the results per shellfish species and per production area showed that there were limited differences in contamination prevalence and levels among diverse bivalve species, while a statistically significant difference was present in quantitative levels of one production area. These data could be useful for the development of both risk assessment models and code of practice for the management of viral contamination in primary production.

  18. Hepatobiliary manifestations of gastrointestinal and nutritional disorders.

    Science.gov (United States)

    Samarasena, Jason B; Hu, Ke-Qin

    2011-02-01

    Hepatobiliary manifestations of gastrointestinal and nutritional disorders can occur as part of the clinical spectrum of the underlying disease or as a consequence of the treatment of the disease. This article reviews aspects of pathogenesis, diagnosis, and management of hepatobiliary manifestations associated with a selection of gastrointestinal and nutritional disorders including inflammatory bowel disease, celiac disease, Whipple's disease, and parenteral nutrition associated disorders. Copyright © 2011 Elsevier Inc. All rights reserved.

  19. Neuropsychiatric Manifestations of Parkinson`s Disease

    Directory of Open Access Journals (Sweden)

    Ana Peixinho

    2014-10-01

    Full Text Available Parkinson’s disease affects about 1% of the world population older than 65 years. It’s most frequently considered a movement disorder, but the neuropsychiatric manifestations associated with the disease and/or its treatment may be of equal or greater significance in some patients. We will discuss briefly the epidemiology, physiopathology and diagnosis of Parkinson’s disease, highlighting the neuropsychiatric manifestations: depression, anxiety, psychosis, dementia, sleep disorders, dopamine dysregulation syndrome.

  20. Neurological manifestations of excessive alcohol consumption.

    Science.gov (United States)

    Planas-Ballvé, Anna; Grau-López, Laia; Morillas, Rosa María; Planas, Ramón

    2017-12-01

    This article reviews the different acute and chronic neurological manifestations of excessive alcohol consumption that affect the central or peripheral nervous system. Several mechanisms can be implicated depending on the disorder, ranging from nutritional factors, alcohol-related toxicity, metabolic changes and immune-mediated mechanisms. Recognition and early treatment of these manifestations is essential given their association with high morbidity and significantly increased mortality. Copyright © 2017 Elsevier España, S.L.U., AEEH y AEG. All rights reserved.

  1. Study of cutaneous manifestations in geriatrics

    OpenAIRE

    Shashikant B. Dhumale; Rajesh Khyalappa

    2016-01-01

    Background: Cutaneous signs and symptoms increases as the age advances. These are physiological as well as pathological changes. They can be due to systemic diseases present in old age. Methods: All the 200 geriatric patients have cutaneous manifestations. Results: Pruritus, eczema, stasis eczema, fungal infections were common. Diabetes was found in large incidence i.e. 27.5%, which show certain skin manifestations like pruritus, skin tag etc. Conclusions: Poor hygiene and systemic ...

  2. SKIN MANIFESTATIONS IN TYPE 2 DIABETES MELLITUS

    OpenAIRE

    Adepu Sumitra Devi; Banoth Mohan Lal

    2016-01-01

    BACKGROUND Skin changes of diabetes mellitus (DM) appear subsequent to the progression of the disease, they can be the sign that appear first in some cases and in others they may present years after the primary disease. AIMS To study the skin manifestations in diabetic patients and to know the incidence of skin manifestations of diabetes mellitus. MATERIAL AND METHODS This study was undertaken at our hospital, MGM Hospital, Warangal, Telangana for a period of one year from ...

  3. Ocular Motor Manifestations of Multiple Sclerosis.

    Science.gov (United States)

    Nerrant, Elodie; Tilikete, Caroline

    2017-09-01

    Multiple sclerosis (MS) is a demyelinating disease of the central nervous system leading to disability, especially in young patients. Acute or chronic lesions of MS within the brainstem and the cerebellum frequently result in ocular motor disorders. This review encompasses the spectrum of ocular motor disorders in patients with MS emphasizing prevalence, examination findings, diagnostic features, functional consequences, classification of MS course, and management of these disturbances of ocular motility. Ocular motor manifestations of MS can occur acutely in relapse or chronically, the latter as a consequence of previous relapses or as a chronic course of the disease. The most frequent and specific acute ocular motor manifestation is uni- or bilateral internuclear ophthalmoplegia (INO). The most frequent chronic manifestations include INO and cerebellar ocular motor disorders such as gaze-evoked nystagmus, saccadic hypermetria, and lack of vestibulo-ocular reflex inhibition. The most disabling syndrome is pendular nystagmus. The high prevalence of ocular motor manifestations emphasizes the importance of neuro-ophthalmological examination among patients with MS. Because chronic manifestations may cause minimal or no symptoms, a systematic investigation of the most common manifestations should be performed in daily practice. Appropriate treatment may improve visual outcome in some of these ocular motor disorders.

  4. Cartilage hair hypoplasia: characteristics and orthopaedic manifestations.

    Science.gov (United States)

    Riley, Patrick; Weiner, Dennis S; Leighley, Bonnie; Jonah, David; Morton, D Holmes; Strauss, Kevin A; Bober, Michael B; Dicintio, Martin S

    2015-04-01

    Cartilage hair hypoplasia (CHH) is a rare metaphyseal chondrodysplasia characterized by short stature and short limbs, found primarily in Amish and Finnish populations. Cartilage hair hypoplasia is caused by mutations in the RMRP gene located on chromosome 9p13.3. The disorder has several characteristic orthopaedic manifestations, including joint laxity, limited elbow extension, ankle varus, and genu varum. Immunodeficiency is of concern in most cases. Although patients exhibit orthopaedic problems, the orthopaedic literature on CHH patients is scant at best. The objective of this study was to characterize the orthopaedic manifestations of CHH based on the authors' unique access to the largest collection of CHH patients ever reported. The authors examined charts and/or radiographs in 135 cases of CHH. We analyzed the orthopaedic manifestations to better characterize and further understand the orthopaedic surgeon's role in this disorder. In addition to describing the clinical characteristics, we report on our surgical experience in caring for CHH patients. Genu varum, with or without knee pain, is the most common reason a patient with CHH will seek orthopaedic consultation. Of the cases reviewed, 32 patients had undergone surgery, most commonly to correct genu varum. This paper characterizes the orthopaedic manifestations of CHH. Characterizing this condition in the orthopaedic literature will likely assist orthopaedic surgeons in establishing a correct diagnosis and appreciating the orthopaedic manifestations. It is important that the accompanying medical conditions are appreciated and evaluated.

  5. Prevalence of cutaneous manifestations of diabetes mellitus

    International Nuclear Information System (INIS)

    Ahmed, K.; Muhammad, Z.; Qayum, I.

    2009-01-01

    Diabetes mellitus (DM) is a clinical syndrome characterized by hyperglycaemia due to absolute or relative insulin deficiency. The aim of this study was to evaluate the frequency of skin manifestations in patients with diabetes mellitus of this area. This descriptive study was conducted in medical out patient door of District Headquarter Hospital Battgram from January 2008 to July 2008. A total of 350 diabetic (types 1 and 2) patients over 15 years of age attending the medical OPD of DHQ Hospital were examined in detail for skin manifestations of the disease. Three hundred and fifty diabetic (type-1 and type-2) patients (193 females and 157 males) enrolled in this study. Mean age of the patients was 54+-8.53 years. Duration of diabetes was between 1-12 years; 320 patients had type-2 and 30 patients had type-1 diabetes mellitus. Patients with uncontrolled disease were 327 and 23 patients showed adequate glycaemic control. Seventy-six percent of patients had cutaneous manifestations. The skin manifestations observed were: skin infections 30.9%, foot gangrene and ulcers 12.9%, pruritus 7.1%, vitiligo 5.7%, yellow skin 4.2%, diabetic dermopathy 4.2%, skin tags 3.7%, acanthosis nigricans 2.9%, eruptive xanthomas 2.6%, necrobiosis lipoidica diabeticorum 1.4%, diabetic bullae 0.6%, and pigmented purpuras in 0.3% patients. Cutaneous manifestations were quite Common in the diabetics of this area. (author)

  6. Articular manifestations in patients with Lyme disease.

    Science.gov (United States)

    Vázquez-López, María Esther; Díez-Morrondo, Carolina; Sánchez-Andrade, Amalia; Pego-Reigosa, Robustiano; Díaz, Pablo; Castro-Gago, Manuel

    To determine the percentage of Lyme patients with articular manifestations in NW Spain and to know their evolution and response to treatment. A retrospective study (2006-2013) was performed using medical histories of confirmed cases of Lyme disease showing articular manifestations. Clinical and laboratory characteristics, together with the treatment and evolution of the patients, were analysed. Seventeen out of 108 LD confirmed patients (15.7%) showed articular manifestations. Regarding those 17 patients, 64.7%, 29.4% and 5.9% presented arthritis, arthralgia and bursitis, respectively. The knee was the most affected joint. Articular manifestations were often associated to neurological, dermatological and cardiac pathologies. Otherwise, most patients were in Stage III. The 11.8% of the cases progressed to a recurrent chronic arthritis despite the administration of an appropriate treatment. Lyme disease patients showing articular manifestations should be included in the diagnosis of articular affections in areas of high risk of hard tick bite, in order to establish a suitable and early treatment and to avoid sequels. Copyright © 2015 Elsevier España, S.L.U. and Sociedad Española de Reumatología y Colegio Mexicano de Reumatología. All rights reserved.

  7. Cutaneous Manifestations of Systemic Lupus Erythematosus

    Science.gov (United States)

    Uva, Luís; Miguel, Diana; Pinheiro, Catarina; Freitas, João Pedro; Marques Gomes, Manuel; Filipe, Paulo

    2012-01-01

    Systemic lupus erythematosus (SLE) is a multiorgan autoimmune disease of unknown etiology with many clinical manifestations. The skin is one of the target organs most variably affected by the disease. The American College of Rheumatology (ACR) established 11 criteria as a classificatory instrument to operationalise the definition of SLE in clinical trials. They were not intended to be used to diagnose individuals and do not do well in that capacity. Cutaneous lesions account for four of these 11 revised criteria of SLE. Skin lesions in patients with lupus may be specific or nonspecific. This paper covers the SLE-specific cutaneous changes: malar rash, discoid rash, photosensitivity, and oral mucosal lesions as well as SLE nonspecific skin manifestations, their pathophysiology, and management. A deeper thorough understanding of the cutaneous manifestations of SLE is essential for diagnosis, prognosis, and efficient management. Thus, dermatologists should cooperate with other specialties to provide optimal care of SLE patient. PMID:22888407

  8. [Pulmonary manifestations in systemic lupus erythematosus].

    Science.gov (United States)

    Vincze, Krisztina; Odler, Balázs; Müller, Veronika

    2016-07-01

    Systemic lupus erythematosus is the most common connective tissue disease that is associated with pulmonary manifestations. Although lupus has the potential to affect any organ, lung involvement is observed during the course of the disease in most cases and it is prognostic for outcome. Pulmonary manifestations in lupus can be classified into five groups based on the anatomical involvement: pleura, lung parenchyma, bronchi and bronchioli, lung vasculature and respiratory muscles can be involved. The most common respiratory manifestations attributable to lupus are pleuritis with or without pleural effusion, pulmonary vascular disease, upper and lower airway dysfunction, parenchymal disease, and diaphragmatic dysfunction (shrinking lung syndrome). In this article the authors summarize lung involvement of lupus, its diagnosis, therapy and prognosis. Orv. Hetil., 2016, 157(29), 1154-1160.

  9. Vertigo as a Predominant Manifestation of Neurosarcoidosis

    Directory of Open Access Journals (Sweden)

    Tasnim F. Imran

    2015-01-01

    Full Text Available Sarcoidosis is a granulomatous disease of unknown etiology that affects multiple organ systems. Neurological manifestations of sarcoidosis are less common and can include cranial neuropathies and intracranial lesions. We report the case of a 21-year-old man who presented with vertigo and uveitis. Extensive workup including brain imaging revealed enhancing focal lesions. A lacrimal gland biopsy confirmed the diagnosis of sarcoidosis. The patient was initially treated with prednisone, which did not adequately control his symptoms, and then was switched to methotrexate with moderate symptomatic improvement. Our patient had an atypical presentation with vertigo as the predominant manifestation of sarcoidosis. Patients with neurosarcoidosis typically present with systemic involvement of sarcoidosis followed by neurologic involvement. Vertigo is rarely reported as an initial manifestation. This case highlights the importance of consideration of neurosarcoidosis as an entity even in patients that may not have a typical presentation or systemic involvement of disease.

  10. Cutaneous Manifestations of Systemic Lupus Erythematosus

    Directory of Open Access Journals (Sweden)

    Luís Uva

    2012-01-01

    Full Text Available Systemic lupus erythematosus (SLE is a multiorgan autoimmune disease of unknown etiology with many clinical manifestations. The skin is one of the target organs most variably affected by the disease. The American College of Rheumatology (ACR established 11 criteria as a classificatory instrument to operationalise the definition of SLE in clinical trials. They were not intended to be used to diagnose individuals and do not do well in that capacity. Cutaneous lesions account for four of these 11 revised criteria of SLE. Skin lesions in patients with lupus may be specific or nonspecific. This paper covers the SLE-specific cutaneous changes: malar rash, discoid rash, photosensitivity, and oral mucosal lesions as well as SLE nonspecific skin manifestations, their pathophysiology, and management. A deeper thorough understanding of the cutaneous manifestations of SLE is essential for diagnosis, prognosis, and efficient management. Thus, dermatologists should cooperate with other specialties to provide optimal care of SLE patient.

  11. Cutaneous manifestations of systemic lupus erythematosus.

    Science.gov (United States)

    Uva, Luís; Miguel, Diana; Pinheiro, Catarina; Freitas, João Pedro; Marques Gomes, Manuel; Filipe, Paulo

    2012-01-01

    Systemic lupus erythematosus (SLE) is a multiorgan autoimmune disease of unknown etiology with many clinical manifestations. The skin is one of the target organs most variably affected by the disease. The American College of Rheumatology (ACR) established 11 criteria as a classificatory instrument to operationalise the definition of SLE in clinical trials. They were not intended to be used to diagnose individuals and do not do well in that capacity. Cutaneous lesions account for four of these 11 revised criteria of SLE. Skin lesions in patients with lupus may be specific or nonspecific. This paper covers the SLE-specific cutaneous changes: malar rash, discoid rash, photosensitivity, and oral mucosal lesions as well as SLE nonspecific skin manifestations, their pathophysiology, and management. A deeper thorough understanding of the cutaneous manifestations of SLE is essential for diagnosis, prognosis, and efficient management. Thus, dermatologists should cooperate with other specialties to provide optimal care of SLE patient.

  12. Molecular and Biochemical Methods Useful for the Epigenetic Characterization of Chromatin-Associated Proteins in Bivalve Molluscs

    Directory of Open Access Journals (Sweden)

    Ciro Rivera-Casas

    2017-08-01

    Full Text Available Bivalve molluscs constitute a ubiquitous taxonomic group playing key functions in virtually all ecosystems, and encompassing critical commercial relevance. Along with a sessile and filter-feeding lifestyle in most cases, these characteristics make bivalves model sentinel organisms routinely used for environmental monitoring studies in aquatic habitats. The study of epigenetic mechanisms linking environmental exposure and specific physiological responses (i.e., environmental epigenetics stands out as a very innovative monitoring strategy, given the role of epigenetic modifications in acclimatization and adaptation. Furthermore, the heritable nature of many of those modifications constitutes a very promising avenue to explore the applicability of epigenetic conditioning and selection in management and restoration strategies. Chromatin provides a framework for the study of environmental epigenetic responses. Unfortunately, chromatin and epigenetic information are very limited in most non-traditional model organisms and even completely lacking in most environmentally and ecologically relevant organisms. The present work aims to provide a comprehensive and reproducible experimental workflow for the study of bivalve chromatin. First, a series of guidelines for the molecular isolation of genes encoding chromatin-associated proteins is provided, including information on primers suitable for conventional PCR, Rapid Amplification of cDNA Ends (RACE, genome walking and quantitative PCR (qPCR experiments. This section is followed by the description of methods specifically developed for the analysis of histone and SNBP proteins in different bivalve tissues, including protein extraction, purification, separation and immunodetection. Lastly, information about available antibodies, their specificity and performance is also provided. The tools and protocols described here complement current epigenetic analyses (usually limited to DNA methylation by incorporating

  13. Suspended material availability and filtration-biodeposition processes performed by a native and invasive bivalve species in streams

    Science.gov (United States)

    Atkinson, C.L.; First, M.R.; Covich, A.P.; Opsahl, S.P.; Golladay, S.W.

    2011-01-01

    Unionid mussels are among the most threatened group of freshwater organisms globally. They are known for their ability to filter food particles from flowing and standing waters. However, invasive bivalve species, such as the Asian clam (Corbicula fluminea) in North America, have the potential to overlap in feeding and potentially out-compete the native species. Yet, the feeding preferences of unionid mussels and C. fluminea are incompletely understood. We hypothesized that Elliptio crassidens (native) and C. fluminea (invasive) would select for specific organic components present within seston. We examined changes in seston (dry mass and ash-free dry mass) resulting from bivalve feeding activity for three size classes of material that were isolated using gravimetric filtration. The treatments were also sub-sampled for flow cytometry (FC) which separated the suspended materials in the stream water into five categories: detritus, heterotrophic bacteria, picoautotrophs, nanoautotrophs, and heterotrophic nanoeukaryotes. Our results indicated that both species of bivalve showed preferences for organic and living materials. E. crassidens preferentially filtered nanoeukaryotes, whose decreases were associated with an increase in bacteria. In contrast, C. fluminea preferred smaller materials through selective filtration of picoautotrophs. In addition, both species increased the concentration of large materials toward the end of the experiment because of the suspension of their pseudofeces biodeposits. To our knowledge, this study is the first to examine grazing by bivalve species on natural stream particulate matter using FC. Our results suggest that native and non-native mussels have different functional roles, which has important implications for organic matter processing and food webs in streams. ?? 2011 Springer Science+Business Media B.V.

  14. Kinetic analysis of uranium accumulation in the bivalve Corbicula fluminea: effect of pH and direct exposure levels

    Energy Technology Data Exchange (ETDEWEB)

    Simon, Olivier; Garnier-Laplace, Jacqueline

    2004-06-10

    The bioaccumulation of natural uranium in the freshwater bivalve Corbicula fluminea was investigated subsequent to the bivalve's experimental waterborne exposures. A first experiment determined the accumulation rate (transfer efficiency, tissular distribution) and subcellular distribution of uranium in organs after over 42 days of uranium exposure (100 {mu}g l{sup -1}; pH 7) and later following 60 days of depuration. Results showed that there was direct transfer of uranium to the bivalve organs ([U]{sub organism}/[U]{sub water} = 0.16, fresh weight, fw). The highest accumulation levels occurred in the visceral mass and remained constant throughout the exposure duration, although a linear increase in the U concentration in the gills was observed (2.98{+-}1.3-10.9{+-}3.7 {mu}g g{sup -1} between Days 2 and 42). A second set of experiments were performed in order to test the influence of the exposure levels (100; 500; 1500 {mu}g l{sup -1}) and pH (7 and 8.1) on the bioaccumulation capacities. A marked difference of U distribution is observed as a function of exposure levels (gills were favoured in the case of high exposure levels-relative burden: 49.1{+-}3% (1500 {mu}g l{sup -1}), whereas the visceral mass presented higher accumulation levels at environmentally relevant U concentrations). Uranium concentration in the insoluble fraction (80%) in the whole body does not depend upon exposure levels in the water column or upon duration. These experiments did not allow any link to be established between the free-metal ion concentration and the bioaccumulation efficiency. Results showed a significant pH effect and indicated a link between the exposure conditions and the distribution of uranium in the bivalve organs.

  15. Polychlorinated biphenyls, organochlorine pesticides and polycyclic aromatic hydrocarbons in a one-off global survey of bivalves

    DEFF Research Database (Denmark)

    Vorkamp, Katrin; Strand, Jakob; Christensen, Jan H.

    2010-01-01

    During the Danish Galathea 3 expedition, bivalve samples were collected at the Faroe Islands, Greenland, Ghana, South Africa, Australia, Solomon Islands, New Zealand, Chile, US Virgin Islands, Boston, Newfoundland and Shetland Islands and analysed for organochlorines and PAHs. Concentration...... in terms of PCB and PAH levels, while other Greenland samples came closest to representing PAH background levels. Several locations had undetectable organochlorine levels, including Hobart and Chile, which had the lowest Sigma PAH concentrations (

  16. Neurologic manifestations of hypothyroidism in dogs.

    Science.gov (United States)

    Bertalan, Abigail; Kent, Marc; Glass, Eric

    2013-03-01

    Hypothyroidism is a common endocrine disease in dogs. A variety of clinicopathologic abnormalities may be present; however, neurologic deficits are rare. In some instances, neurologic deficits may be the sole manifestation of hypothyroidism. Consequent ly, the diagnosis and management of the neurologic disorders associated with hypothyroidism can be challenging. This article describes several neurologic manifestations of primary hypothyroidism in dogs; discusses the pathophysiology of hypothyroidism-induced neurologic disorders affecting the peripheral and central nervous systems; and reviews the evidence for the neurologic effects of hypothyroidism.

  17. Life-Threatening Cardiac Manifestations of Pheochromocytoma

    Directory of Open Access Journals (Sweden)

    Luiz R. Leite

    2010-01-01

    Full Text Available Pheochromocytoma is a catecholamine-secreting tumor of the adrenal glands, usually with benign manifestations, whose typical clinical presentation includes the triad of headache, palpitations and diaphoresis. However, a wide range of signs and symptoms may be present. In the cardiovascular system, the most common signs are labile hypertension and sinus tachycardia. Systolic heart failure and ST-segment deviations mimicking myocardial infarction have also been reported, as well as QT interval prolongation and, rarely, ventricular tachycardia. We describe a challenging diagnosis of pheochromocytoma with many cardiovascular manifestations, which could have been missed due to the absence of typical symptoms.

  18. Dental Manifestations of Pediatric Bone Disorders.

    Science.gov (United States)

    Yepes, Juan F

    2017-12-01

    Several bone disorders affecting the skeleton often are manifest in the maxillofacial region. This review presents the most common bone disorders in children and their dental-oral manifestations: fibrous dysplasia, Paget's disease, osteogenesis imperfecta, renal osteodystrophy, hypophosphatasia, and osteoporosis. The specific intraoral characteristics will reviewed in detail. Recent studies confirmed the close relationship between the mandible and the maxilla with the most prevalent systemic bone disorders in children. This review will help practitioners to integrate the oral health into the systemic health and improve the multidisciplinary approach of pediatric patients between medicine and dentistry.

  19. Field chronobiology of a molluscan bivalve: how the moon and sun cycles interact to drive oyster activity rhythms.

    Science.gov (United States)

    Tran, Damien; Nadau, Arnaud; Durrieu, Gilles; Ciret, Pierre; Parisot, Jean-Paul; Massabuau, Jean-Charles

    2011-05-01

    The present study reports new insights into the complexity of environmental drivers in aquatic animals. The focus of this study was to determine the main forces that drive mollusc bivalve behavior in situ. To answer this question, the authors continuously studied the valve movements of permanently immersed oysters, Crassostrea gigas, during a 1-year-long in situ study. Valve behavior was monitored with a specially build valvometer, which allows continuously recording of up to 16 bivalves at high frequency (10 Hz). The results highlight a strong relationship between the rhythms of valve behavior and the complex association of the sun-earth-moon orbital positions. Permanently immersed C. gigas follows a robust and strong behavior primarily driven by the tidal cycle. The intensity of this tidal driving force is modulated by the neap-spring tides (i.e., synodic moon cycle), which themselves depend of the earth-moon distance (i.e., anomalistic moon cycle). Light is a significant driver of the oysters' biological rhythm, although its power is limited by the tides, which remain the predominant driver. More globally, depending where in the world the bivalves reside, the results suggest their biological rhythms should vary according to the relative importance of the solar cycle and different lunar cycles associated with tide generation. These results highlight the high plasticity of these oysters to adapt to their changing environment.

  20. Polycyclic Aromatic Hydrocarbons in Sediments and Bivalves on the Pacific Coast of Japan: Influence of Tsunami and Fire.

    Directory of Open Access Journals (Sweden)

    Mayu Onozato

    Full Text Available Surface sediments and at least one edible bivalve species (Ruditapes philippinarum, Mytilus galloprovincialis, and Crassostrea gigas were collected from each of seven intertidal sites in Japan in 2013. The sites had experienced varying levels of tsunami and fire disturbance following the major earthquake of 2011. Eight polycyclic aromatic hydrocarbons (PAHs were identified and analyzed by gas chromatography-mass spectrometry. Total sediment PAH concentration (CT, the sum of the average concentrations of the eight PAHs, was 21-1447 μg kg-1-dry. Relative to the average level of one type of PAH in sediments collected around Japan in 2002 (benzo[a]pyrene = 21 μg kg-1-dry, five of the seven sites showed concentrations significantly lower than this average in 2013. The CTs for the three bivalves (134-450 μg kg-1-dry were within the range of the previous reports (2.2-5335 μg kg-1-dry. The data suggest that the natural disaster did not increase PAH concentrations or affect the distribution within sediment or bivalves in Tohoku district. Although PAH concentrations at the sites pose no risk to human health, the findings highlight that the observed PAH levels derive from pre- rather than post-quake processes.

  1. Investigation into Cryptosporidium and Giardia in bivalve mollusks farmed in Sardinia region and destined for human consumption

    Directory of Open Access Journals (Sweden)

    Tiziana Tedde

    2013-06-01

    Full Text Available Cryptosporidium and Giardia are protozoan parasites transmitted by fecal-oral ingestion of (oocysts, and are responsible for enteritis in several animal species and humans worldwide. These (oocysts can survive for over a year in aquatic environments and can accumulate in bivalve mollusks, which filter large volumes of water. The aim of this study is to evaluate the natural occurrence of Cryptosporidium and Giardia contamination in different specimens of edible bivalves mollusks from farming sites of the western and north-eastern coasts of Sardinia. From April 2011 to February 2012, 1095 specimens of Mytilus galloprovincialis and 240 of Crassostrea gigas were sampled from Olbia and Oristano gulf and San Teodoro pond. Hepatopancreas and gills, including the labial palp, were examined for oocysts and cysts after pooling and homogenisation using different techniques: i staining for light and fluorescence microscopy; ii direct immunofluorescence (IF Merifluor® test Cryptosporidium/ Giardia (Meridian Bioscience Inc., Cincinnati, OH, USA; and iii molecular procedures. However, in the context under study, all mollusks examined with the three main diagnostic techniques were negative for both parasites pointing out the hypothetically low zoonotic risk related to Cryptosporidium and Giardia in bivalves, especially Mytilus galloprovincialis and Crassostrea gigas.

  2. Thermal processing of live bivalve molluscs for controlling viruses: On the need for a risk-based design.

    Science.gov (United States)

    Messens, Winy; Fernandez-Escamez, Pablo S; Lees, David; Lindqvist, Roland; O'Mahony, Michael; Suffredini, Elisabetta; Cortiñas Abrahantes, José; Chantzis, Emmanouil; Koutsoumanis, Kostas

    2017-07-19

    Norovirus (NoV) and Hepatitis A virus (HAV) are the most important viral hazards associated with human illness following consumption of contaminated bivalve molluscs. The effectiveness of the current EU criteria for heat processing of bivalve molluscs (i.e. raising the temperature of the internal mollusc flesh to at least 90°C for a minimum of 90 seconds) was evaluated using predictive microbiology. A HAV thermal inactivation model was developed based on literature data in mollusc matrices during isothermal heat treatment. Application of the developed model demonstrated that the 90°C-90 s requirement may lead to significantly different virus inactivation depending on the commercial process design. This shows the need for the establishment of a Performance Criterion for bivalve molluscs heat processing which will assure a common specified level of consumer protection. A risk-based approach is described that allows for an effective processing design providing a more transparent and objective relation between the thermal processing targets and public health. Model simulations demonstrate that the F-value is a more appropriate Process Criterion than a single time-temperature combination since it enables the food business operators to design a process that is compliant with the safety requirements while at the same time achieving a desired product quality.

  3. A comparative study on effects of heterotrophic microbial activity on the stability of bivalve and coral carbonate during early diagenesis.

    Science.gov (United States)

    Lange, Skadi M.; Krause, Stefan; Immenhauser, Adrian; Ritter, Ann-Christin; Gorb, Stanislav N.; Kleinteich, Thomas; Treude, Tina

    2016-04-01

    Following deposition and shallow burial, marine biogenic carbonates are exposed to an environment that is geochemically affected by a manifold of bacterial metabolic redox processes. To allow for comparison of potential microbe-mediated alteration effects on carbonates, we used aragonitic bivalve shell samples and porous aragonitic coral fragments for incubation experiments in oxic- and anoxic seawater media. The media contained marine sediment slurries or bacterial cultures to mimic the natural processes in vitro. The results for anoxic experimental media containing bivalve shell samples or coral fragments displayed considerable changes in carbonate-system parameters (pH, AT, CA, DIC) and divalent-cation ratios (Mg/Ca, Mg/Sr, Sr/Ca) over time. Furthermore, incubated bivalve shell samples were altered in morphology, elemental composition and isotopic signature. Coral-fragment bearing oxic incubations were run at two temperature regimes and divalent-cation ratios of the high-temperature bacterial medium displayed withdrawal of Ca2+ and Sr2+ from the medium, thus indicating microbe-induced secondary aragonite precipitation. Analyses of coral fragments include electron-microprobe mapping and X-ray microtomography to resolve elemental sample composition and pore-space alteration features, respectively. Up to this point our results indicate that heterotrophic bacterial activity has the potential to affect surficial or open pore space in carbonate archives by increasing rates of alteration relative to sterile environments.

  4. Anatomical study on Myoforceps aristatus, an invasive boring bivalve in S.E. Brazilian coast (Mytilidae

    Directory of Open Access Journals (Sweden)

    Luiz Ricardo L. Simone

    2006-01-01

    Full Text Available The bivalve Myoforceps aristatus (Dillwyn, 1817, also known as Lithophaga aristata, have been recently collected in the coasts of Rio de Janeiro and São Paulo, Brazil; a species that bores shells of other mollusks. This occurrence has been interpreted as an invasion of this species, originally from the Caribbean. The distinguishing character of the species is the posterior extensions of the shell crossing with each other. Because specimens with this character have also been collected in the Pacific Ocean, they all have been considered a single species. However, it is possible that more than one species may be involved in such worldwide distribution. With the objective of providing full information based on Atlantic specimens, a complete anatomical description is provided, which can be used in comparative studies with specimens from other oceans. Additional distinctive features of M. aristatus are the complexity of the incurrent siphon, the kidney opening widely into the supra-branchial chamber (instead of via a nephropore, and the multi-lobed auricle.O bivalve Myoforceps aristatus (Dillwyn, 1817, também conhecido como Lithophaga aristata, tem sido recentemente coletado nas costas do Rio de Janeiro e São Paulo, Brasil; uma espécie que perfura conchas de outros moluscos. Esta ocorrência está sendo interpretada como uma invasão de uma espécie originada do Caribe. O caráter distintivo da espécie é a região posterior da concha, com extensões que se cruzam. Como espécimes com esta característica também têm sido coletados no oceano Pacífico, eles tem sido considerados como pertencentes à mesma espécie. Entretanto, é possível que mais de uma espécie possam estar envolvidas nesta suposta distribuição mundial. Com o objetivo de fornecer informação completa baseada em material do Atlântico, uma descrição anatômica completa é dada, a qual pode ser usada em estudos comparativos com espécimes de outros oceanos. As caracter

  5. Calibration of hydroclimate proxies in freshwater bivalve shells from Central and West Africa

    Science.gov (United States)

    Kelemen, Zita; Gillikin, David P.; Graniero, Lauren E.; Havel, Holly; Darchambeau, François; Borges, Alberto V.; Yambélé, Athanase; Bassirou, Alhou; Bouillon, Steven

    2017-07-01

    Freshwater bivalve shell oxygen and carbon stable isotope ratios (δ18O, δ13C) may act as recorders of hydroclimate (e.g., precipitation-evaporation balance, discharge) and aquatic biogeochemistry. We investigate the potential of these hydroclimate proxies measured along the growth axis of shells collected from the Oubangui River (Bangui, Central African Republic) and the Niger River (Niamey, Niger). Biweekly water samples and in situ measurements collected over several years, along with daily discharge data from both sites allowed a direct comparison with proxies recorded in the shells. Data from a total of 14 unionid shells, including three species (Chambardia wissmanni, Aspatharia dahomeyensis, and Aspatharia chaiziana), confirmed that shells precipitate carbonate in oxygen isotope equilibrium with ambient water. Because water temperature variations were small, shell δ18O values (δ18Oshell) also accurately record the seasonality and the range observed in water δ18O (δ18Ow) values when calculated using an average temperature. Calculated δ18Ow values were in good agreement over the entire record of measured δ18Ow values, thus δ18Oshell records can be reliably used to reconstruct past δ18Ow values. Discharge and δ18Ow values from both rivers fit a logarithmic relationship, which was used to attempt reconstruction of past hydrological conditions, after calculating δ18Ow values from δ18Oshell values. A comparison with measured discharge data suggests that for the two rivers considered, δ18Oshell data are good proxies for recording discharge conditions during low(er) discharge levels, but that high discharge values cannot be accurately reconstructed due to the large scatter in the discharge-δ18Ow relationship. Moreover, periods of bivalve shell growth cessation due to high turbidity or air exposure should be taken into account. While δ13C values of dissolved inorganic carbon in both rivers showed clear seasonality and correlated well with discharge

  6. Ocean acidification at high latitudes: potential effects on functioning of the Antarctic bivalve Laternula elliptica.

    Directory of Open Access Journals (Sweden)

    Vonda Cummings

    Full Text Available Ocean acidification is a well recognised threat to marine ecosystems. High latitude regions are predicted to be particularly affected due to cold waters and naturally low carbonate saturation levels. This is of concern for organisms utilising calcium carbonate (CaCO(3 to generate shells or skeletons. Studies of potential effects of future levels of pCO(2 on high latitude calcifiers are at present limited, and there is little understanding of their potential to acclimate to these changes. We describe a laboratory experiment to compare physiological and metabolic responses of a key benthic bivalve, Laternula elliptica, at pCO(2 levels of their natural environment (430 µatm, pH 7.99; based on field measurements with those predicted for 2100 (735 µatm, pH 7.78 and glacial levels (187 µatm, pH 8.32. Adult L. elliptica basal metabolism (oxygen consumption rates and heat shock protein HSP70 gene expression levels increased in response both to lowering and elevation of pH. Expression of chitin synthase (CHS, a key enzyme involved in synthesis of bivalve shells, was significantly up-regulated in individuals at pH 7.78, indicating L. elliptica were working harder to calcify in seawater undersaturated in aragonite (Ω(Ar = 0.71, the CaCO(3 polymorph of which their shells are comprised. The different response variables were influenced by pH in differing ways, highlighting the importance of assessing a variety of factors to determine the likely impact of pH change. In combination, the results indicate a negative effect of ocean acidification on whole-organism functioning of L. elliptica over relatively short terms (weeks-months that may be energetically difficult to maintain over longer time periods. Importantly, however, the observed changes in L. elliptica CHS gene expression provides evidence for biological control over the shell formation process, which may enable some degree of adaptation or acclimation to future ocean acidification scenarios.

  7. Manganese in the shell of the bivalve Mytilus edulis: Seawater Mn or physiological control?

    Science.gov (United States)

    Freitas, Pedro S.; Clarke, Leon J.; Kennedy, Hilary; Richardson, Christopher A.

    2016-12-01

    Manganese in the shell calcite of marine bivalves has been suggested to reflect ambient seawater Mn concentrations, thus providing a high-resolution archive of past seawater Mn concentrations. However, a quantitative relationship between seawater Mn and shell Mn/Ca ratios, as well as clear understanding of which process(es) control(s) shell Mn/Ca, are still lacking. Blue mussels, Mytilus edulis, were grown in a one-year duration field experiment in the Menai Strait, U.K., to study the relationship between seawater particulate and dissolved Mn2+ concentrations and shell calcite Mn/Ca ratios. Shell Mn/Ca showed a well-defined intra-annual double-peak, with maximum values during early spring and early summer and low values during autumn and winter. Seawater particulate Mn peaked during winter and autumn, with a series of smaller peaks during spring and summer, whereas dissolved Mn2+ exhibited a marked single maximum during late-spring to early-summer, being low during the remainder of the year. Consequently, neither seawater particulate Mn nor dissolved Mn2+ concentrations explain the intra-annual variation of shell Mn/Ca ratios. A physiological control on shell Mn/Ca ratios is evident from the strong similarity and timing of the double-peaked intra-annual variations of Mn/Ca and shell growth rate (SGR), the latter corresponding to periods of increased metabolic activity (as indicated by respiration rate). It is thus likely that in M. edulis SGR influences shell Mn/Ca by altering the concentration or activity of Mn2+ within the extra-pallial fluid (EPF), by changing the flux of Mn into or the proportion of protein bound Mn within the EPF. By linking shell Mn/Ca ratios to the endogenous and environmental factors that determine growth and metabolic activity, this study helps to explain the lack of a consistent relationship between shell Mn/Ca in marine bivalve shell calcite and seawater particulate and dissolved Mn2+ concentrations. The use of Mn content from M. edulis

  8. Parasites of economically important bivalves from the southern coast of Bahia State, Brazil Parasitos de bivalves de interesse econômico no Litoral Sul do Estado da Bahia, Brasil

    Directory of Open Access Journals (Sweden)

    Gabriela Calvi Zeidan

    2012-12-01

    Full Text Available This study investigated the parasites of three commercially important bivalve species (Crassostrea rhizophorae, Mytella guyanensis and Lucina pectinata from the southern coast of Bahia, Brazil. A total of 540 specimens were collected in August 2009 and February 2010, at three localities. The bivalve specimens were measured on their longest axis, opened, and macroscopically examined for the presence of parasites or signs of disease. They were then fixed in Davidson' solution and subjected to routine histological processing, with paraffin embedding and H&E staining; next, the specimens were examined under a light microscope. No parasites were observed associated with L. pectinata. Rickettsia-like organisms (RLOs, Sphenophrya sp. (Ciliophora, Nematopsis sp. (Apicomplexa, Urastoma sp. (Turbellaria and Bucephalus sp. (Digenea were observed in both C. rhizophorae and M. guyanensis, as well as Ancistrocoma sp. (Ciliophora and Tylocephalum sp. (Cestoda in the former. A high prevalence of Nematopsis sp. was seen, but caused no apparent damage to the host. Bucephalus sp. caused the destruction of tissues, with castration, but showed low prevalence. The other parasites occurred in low prevalence and intensity, without causing significant damage.Neste estudo foram investigados os parasitos de três espécies de bivalves de interesse econômico (Crassostrea rhizophorae, Mytella guyanensis e Lucina pectinata da Bahia. Foram analisados 540 exemplares, obtidos em duas coletas (agosto-2009 e fevereiro-2010, em três localidades. Os bivalves foram medidos quanto ao seu maior eixo, abertos e examinados macroscopicamente quanto à presença de parasitos ou sinais de enfermidades. Depois disso, foram fixados em solução de Davidson e processados por rotina de histologia, com inclusão em parafina e coloração com H&E. O material foi examinado ao microscópio de luz. Nenhum parasito esteve associado a L. pectinata. Bactérias do tipo RLOs (organismos assemelhados a

  9. Spectrum of Eosinophilic End-Organ Manifestations

    OpenAIRE

    Akuthota, Praveen; Weller, Peter F.

    2015-01-01

    Eosinophil-associated disorders can affect practically all tissues and organs in the body, either individually or in combination. This article provides an overview of end-organ manifestations of eosinophilia, discussing selected organ systems including the upper and lower respiratory, cardiovascular, gastrointestinal, nervous, dermatologic, and renal systems. Mechanisms by which eosinophilia leads to end-organ damage are also considered.

  10. CT manifestations of pulmonary Langerhans cell histiocytosis

    International Nuclear Information System (INIS)

    Qiang Jun; Yu Wei; Gao Wanqin; Song Haiqiao; Ma Yingjian

    2010-01-01

    Objective: To analyzes the CT manifestations of pulmonary Langerhans cell histiocytosis (PLCH). Methods: CT features of 11 patients with PLCH proved pathologically were analyzed retrospectively. Results: The main findings in 11 PLCHs were cysts and nodules. Two cases only had cysts, and 1 only had nodules, which most had cavitations. The other 8 cases showed cysts and nodules with 4 cases mainly manifested with cysts and nine mainly manifested with nodules. Two cases had pulmonary interstitial changes. One case only had cysts in the left upper lung field and 10 cases had lesions not only in the upper and middle but in the lower lung field, which 2 cases had more lesions in the lower and costo-phrenic angle field and 8 cases had less lesions in the costo-phrenic angle field. Three of these 8 cases had more lesions in the superior lobe and apical segment of lower lobe. Conclusion: CT manifestations of PLCH are helpful for the early diagnosis. (authors)

  11. 19 CFR 122.75 - Complete manifest.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Complete manifest. 122.75 Section 122.75 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY AIR COMMERCE REGULATIONS Documents Required for Clearance and Permission To Depart; Electronic...

  12. Imaging the Abdominal Manifestations of Cystic Fibrosis

    Directory of Open Access Journals (Sweden)

    C. D. Gillespie

    2017-01-01

    Full Text Available Cystic fibrosis (CF is a multisystem disease with a range of abdominal manifestations including those involving the liver, pancreas, and kidneys. Recent advances in management of the respiratory complications of the disease has led to a greater life expectancy in patients with CF. Subsequently, there is increasing focus on the impact of abdominal disease on quality of life and survival. Liver cirrhosis is the most important extrapulmonary cause of death in CF, yet significant challenges remain in the diagnosis of CF related liver disease. The capacity to predict those patients at risk of developing cirrhosis remains a significant challenge. We review representative abdominal imaging findings in patients with CF selected from the records of two academic health centres, with a view to increasing familiarity with the abdominal manifestations of the disease. We review their presentation and expected imaging findings, with a focus on the challenges facing diagnosis of the hepatic manifestations of the disease. An increased familiarity with these abdominal manifestations will facilitate timely diagnosis and management, which is paramount to further improving outcomes for patients with cystic fibrosis.

  13. Neurological Manifestations of Medical Child Abuse.

    Science.gov (United States)

    Doughty, Katharine; Rood, Corey; Patel, Anup; Thackeray, Jonathan D; Brink, Farah W

    2016-01-01

    Medical child abuse occurs when a child receives unnecessary and harmful, or potentially harmful, medical care at the instigation of a caretaker through exaggeration, falsification, or induction of symptoms of illness in a child. Neurological manifestations are common with this type of maltreatment. We sought to review common reported neurological manifestations that may alert the clinician to consider medical child abuse. In addition, the possible sequelae of this form of child maltreatment is discussed, as well as practice recommendations for establishing the diagnosis and stopping the abuse once it is identified. A review of the medical literature was conducted regarding the reported neurological presentations of this entity. Neurological manifestations of medical child abuse include false reports of apparent life-threatening events and seizures and reports of induction of symptoms from poisoning. Failure to correlate objective findings with subjective complaints may lead to unnecessary and potentially harmful testing or treatment. This form of child maltreatment puts a child at significant risk of long-term morbidity and mortality. A wide variety of neurological manifestations have been reported in cases of medical child abuse. It is important for the practicing neurologist to include medical child abuse on the differential diagnosis. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Gastrointestinal Manifestations in X-linked Agammaglobulinemia.

    Science.gov (United States)

    Barmettler, Sara; Otani, Iris M; Minhas, Jasmit; Abraham, Roshini S; Chang, Yenhui; Dorsey, Morna J; Ballas, Zuhair K; Bonilla, Francisco A; Ochs, Hans D; Walter, Jolan E

    2017-04-01

    X-linked agammaglobulinemia is a primary humoral immunodeficiency characterized by hypogammaglobulinemia and increased susceptibility to infection. Although there is increased awareness of autoimmune and inflammatory complications in X-linked agammaglobulinemia (XLA), the spectrum of gastrointestinal manifestations has not previously been fully explored. We present a case report of a family with two affected patients with XLA. Given the gastrointestinal involvement of the grandfather in this family, we performed a retrospective descriptive analysis of XLA patients with reported diagnoses of GI manifestations and inflammatory bowel disease (IBD) or enteritis registered at the United States Immunodeficiency Network, a national registry of primary immunodeficiencies. In this cohort of patients with XLA, we found that up to 35% had concurrent gastrointestinal manifestations, and 10% had reported diagnoses of IBD or enteritis. The most commonly reported mutations were missense, which have been associated with a less severe XLA phenotype in the literature. The severity of symptoms were wide ranging, and management strategies were diverse and mainly experimental. Patients with XLA may require close monitoring with particular attention for GI manifestations including IBD and infectious enteritis. Further studies are needed to improve diagnosis and management of GI conditions in XLA patients.

  15. Rheumatic manifestations of inflammatory bowel disease.

    Science.gov (United States)

    Rodríguez-Reyna, Tatiana Sofía; Martínez-Reyes, Cynthia; Yamamoto-Furusho, Jesús Kazúo

    2009-11-28

    This article reviews the literature concerning rheumatic manifestations of inflammatory bowel disease (IBD), including common immune-mediated pathways, frequency, clinical course and therapy. Musculoskeletal complications are frequent and well-recognized manifestations in IBD, and affect up to 33% of patients with IBD. The strong link between the bowel and the osteo-articular system is suggested by many clinical and experimental observations, notably in HLA-B27 transgenic rats. The autoimmune pathogenic mechanisms shared by IBD and spondyloarthropathies include genetic susceptibility to abnormal antigen presentation, aberrant recognition of self, the presence of autoantibodies against specific antigens shared by the colon and other extra-colonic tissues, and increased intestinal permeability. The response against microorganisms may have an important role through molecular mimicry and other mechanisms. Rheumatic manifestations of IBD have been divided into peripheral arthritis, and axial involvement, including sacroiliitis, with or without spondylitis, similar to idiopathic ankylosing spondylitis. Other periarticular features can occur, including enthesopathy, tendonitis, clubbing, periostitis, and granulomatous lesions of joints and bones. Osteoporosis and osteomalacia secondary to IBD and iatrogenic complications can also occur. The management of the rheumatic manifestations of IBD consists of physical therapy in combination with local injection of corticosteroids and nonsteroidal anti-inflammatory drugs; caution is in order however, because of their possible harmful effects on intestinal integrity, permeability, and even on gut inflammation. Sulfasalazine, methotrexate, azathioprine, cyclosporine and leflunomide should be used for selected indications. In some cases, tumor necrosis factor-alpha blocking agents should be considered as first-line therapy.

  16. Mechanisms And Variegated Manifestations Of Inteference In ...

    African Journals Online (AJOL)

    Nigerian bilinguals' use of English as a second language is fraught with interference from L1 to L2, a phenomenon that is commonplace world-wide as a linguistic enterprise. But the extent of this trend in bilinguals varies from one language to another based on sociolinguistic and cultural variables. In Nigeria, manifestations ...

  17. Caracterisation des dechets solides des grandes manifestations ...

    African Journals Online (AJOL)

    This situation aggravates the structural inadequacy of the city managers and leads to unsanitary. The content of a pilgrim's trash behaves like a mirror reflecting his consumption habits, his attitude towards a manifestation of piety in the public space considered as private area as well as a no man's land. Keywords: Dassa ...

  18. MANIFESTATIONS NEURO-OPHTHALMOLOGIQUES DE LA ...

    African Journals Online (AJOL)

    Background Human African trypanosomiasis is a re-emerging parasitic disease that affects the central nervous system and leads to severe neurologic manifestations in the late stage of the disease. Little is known about the prevalence of neuro-ophthalmologic disturbances in patients with human African trypanosomiasis ...

  19. Kerosene poisoning--varied systemic manifestations.

    Science.gov (United States)

    Patel, A L; Shaikh, W A; Patel, H L; Deshmukh, D; Malaviya, A P; Janawar, P; Londhe, V; Dodheja, H

    2004-01-01

    We report here unusual clinical manifestations in a case of kerosene poisoning. The patient presented with encephalopathy and in the course of stay in the hospital developed renal tubular acidosis, delayed first-degree burns and myocarditis. With supportivetherapy the patient recovered completely and was discharged without any sequelae.

  20. Diverse Neurological Manifestations of Lead Encephalopathy ...

    African Journals Online (AJOL)

    Three patients with lead encephalopathy due to industrial poisoning are presented. They all showed a wide spectrum of neurological manifestations, which mimic other neurological presentations. It is emphasised that lead poisoning still occurs in industry, despite efforts at prevention. S. Afr. Med. J., 48, 1721 (1974) ...

  1. Radiological pulmonary manifestations of acquired immunodeficiency syndrome

    International Nuclear Information System (INIS)

    Marchiori, Edson; Melo, Alessandro Severo Alves de; Ossa, Alfonso Jaramillo

    1999-01-01

    In this article are reviewed the principal radiologic manifestations of inflammatory and tumoral diseases the compromise the lungs of patients with acquired immunodeficiency syndrome. In the group of inflammatory diseases the radiologic aspects of pneumocystosis, cytomegalovirus disease, cryptococcosis, tuberculosis and bacterial pneumonias are emphasized. In the neoplasic diseases' group the aspects of lymphoma and Kaposi's sarcoma are specially presented. (author)

  2. Gastrointestinal manifestations in children with primary ...

    African Journals Online (AJOL)

    Ehab

    clinical feature is recurrent and/or severe infections. However, some type ... Table 1. Primary Immunodeficiency Diseases with Gastrointestinal Manifestations. Primary ... Inflammatory bowel disease, IFN-γ; interferon-γ, Igs; immunoglobulins, IL-12; interleukin-12, IPEX; Immune dysregulation polyendocrinopathy enteropathy ...

  3. Neurological and neurosurgical manifestations of human ...

    African Journals Online (AJOL)

    memory and concentration supervene. In the late stage the patient manifests ataxia with brisk tendon ... Cognitive defects of speech and memory also occur6. CT scan shows brain atrophy and ventricular dilatation in .... Under such circumstances treatment is symptomatic, consisting of the use of analgesia and sedation.

  4. Irradiated bivalve mollusks: Use of EPR spectroscopy for identification and dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Alberti, Angelo, E-mail: aalberti@isof.cnr.it [CNR-ISOF, Area della Ricerca di Bologna, Via P. Gobetti 101, Bologna I-40129 (Italy); Chiaravalle, Eugenio [Istituto Zooprofilattico Sperimentale della Puglia e Basilicata, Via Manfredonia 20, Foggia I-71100 (Italy); Fuochi, Piergiorgio; Macciantelli, Dante [CNR-ISOF, Area della Ricerca di Bologna, Via P. Gobetti 101, Bologna I-40129 (Italy); Mangiacotti, Michele, E-mail: michelemangiacotti@libero.it [Istituto Zooprofilattico Sperimentale della Puglia e Basilicata, Via Manfredonia 20, Foggia I-71100 (Italy); Marchesani, Giuliana [Istituto Zooprofilattico Sperimentale della Puglia e Basilicata, Via Manfredonia 20, Foggia I-71100 (Italy); Plescia, Elena [CNR-ISOF, Area della Ricerca di Bologna, Via P. Gobetti 101, Bologna I-40129 (Italy)

    2011-12-15

    High energy radiation treatment of foodstuff for microbial control and shelf-life extension is being used in many countries. However, for consumer protection and information, the European Union has adopted the Directives 1999/2/EC and 1999/3/EC to harmonize the rules concerning the treatment and trade of irradiated foods in EU countries. Among the validated methods to detect irradiated foods the EU directives also include Electron Paramagnetic Resonance (EPR/ESR) spectroscopy. We describe herein the use of EPR for identification of four species of bivalve mollusks, i.e. brown Venus shells (Callista chione), clams (Tapes semidecussatus), mussels (Mytilus galloprovincialis) and oysters (Ostrea edulis) irradiated with {sup 60}Co {gamma}-rays. EPR could definitely identify irradiated seashells due to the presence of long-lived free radicals, primarily CO{sub 2}{sup -}, CO{sub 3}{sup 3-}, SO{sub 2}{sup -} and SO{sub 3}{sup -} radical anions. The presence of other organic free radicals, believed to originate from conchiolin, a scleroprotein present in the shells, was also ascertained. The use of one of these radicals as a marker for irradiation of brown Venus shells and clams can be envisaged. We also propose a dosimetric protocol for the reconstruction of the administered dose in irradiated oysters. - Highlights: > EPR spectroscopy is confirmed a valuable identification tool for irradiated mollusks. > A conchiolin-derived radical can be used as irradiation marker for some mollusks. > A reliable protocol is outlined for dose reconstruction of irradiated oysters.

  5. Habitat creation and biodiversity maintenance in mangrove forests: teredinid bivalves as ecosystem engineers

    Science.gov (United States)

    Michie, Laura; Taylor, Ben W.

    2014-01-01

    Substantial amounts of dead wood in the intertidal zone of mature mangrove forests are tunnelled by teredinid bivalves. When the tunnels are exposed, animals are able to use tunnels as refuges. In this study, the effect of teredinid tunnelling upon mangrove forest faunal diversity was investigated. Mangrove forests exposed to long emersion times had fewer teredinid tunnels in wood and wood not containing teredinid tunnels had very few species and abundance of animals. However, with a greater cross-sectional percentage surface area of teredinid tunnels, the numbers of species and abundance of animals was significantly higher. Temperatures within teredinid-attacked wood were significantly cooler compared with air temperatures, and animal abundance was greater in wood with cooler temperatures. Animals inside the tunnels within the wood may avoid desiccation by escaping the higher temperatures. Animals co-existing in teredinid tunnelled wood ranged from animals found in terrestrial ecosystems including centipedes, crickets and spiders, and animals found in subtidal marine ecosystems such as fish, octopods and polychaetes. There was also evidence of breeding within teredinid-attacked wood, as many juvenile individuals were found, and they may also benefit from the cooler wood temperatures. Teredinid tunnelled wood is a key low-tide refuge for cryptic animals, which would otherwise be exposed to fishes and birds, and higher external temperatures. This study provides evidence that teredinids are ecosystem engineers and also provides an example of a mechanism whereby mangrove forests support intertidal biodiversity and nurseries through the wood-boring activity of teredinids. PMID:25276505

  6. Use of a bivalved polypropylene orthosis in the postoperative management of idiopathic scoliosis.

    Science.gov (United States)

    Roberts, R S; Price, C T; Riddick, M F

    1984-05-01

    Forty-four consecutive patients with idiopathic scoliosis treated by posterior spinal fusion and Harrington rod instrumentation were immobilized after surgery with bivalved polypropylene orthoses. Immediate ambulation was allowed, and the patients wore the orthoses for a mean of 5.9 months. Brace removal was permitted with the patient recumbent for sponge bathing. These patients were followed up for a mean of 2.1 years (range, 1.0-4.3 years). The average final correction for all curves was 45%. The average loss of correction was 2.4 degrees (5.3%). Combined distraction and compression instrumentation was found to improve final correction in all curves by 3 degrees (6.2%) as compared with distraction instrumentation alone. There were no pseudarthroses and no rod breakage. Patients enjoyed the benefits of improved personal hygiene, pleasing cosmetic appearance, and increased life-style flexibility, especially swimming, which was not possible with the conventional Risser plaster cast. Use of the polypropylene orthosis offers significant advantages as compared with previous methods of postoperative management: it not only provides consistently good results but is enthusiastically accepted by patients as well.

  7. Facultative parasitism by the bivalve Kurtiella pedroana in the sand crab Emerita analoga

    Science.gov (United States)

    Bhaduri, Ritin; Valentich-Scott, Paul; Hilgers, Mark; Singh, Rajvir; Hickman, Mikaila; Lafferty, Kevin D.

    2017-01-01

    It is rare that an organism capable of independent or commensalistic existence can also become endoparasitic on a host. In this study, we documented a potential step toward parasitism in the commensal clam Kurtiella pedroana (Bivalvia: Galeommatoidea). Galeommatoideans are known commensals of various invertebrates, including crustaceans. Emerita analoga (Decapoda: Hippidae) is an abundant intertidal decapod inhabiting sandy beaches of the Pacific coast of North and South America. Crabs collected from Monterey Bay, California, were measured and examined externally and internally for associated molluscs. Out of the 520 crabs, 37 large female individuals harbored 49 bivalves (prevalence of 7.11% and mean intensity of 1.3). Forty-one ectocommensal clams were either inside the crab's branchial chambers or on their lateroventral surfaces, and were attached by byssal threads. Our key finding was eight clams that lacked byssal threads and were living in the hemocoel. These internal clams were significantly smaller than the ectocommensals. Because these internal clams lacked access to their normal food, we hypothesize they might have fed on their host's hemolymph as would a parasite. This clam species likely can't reproduce inside its host, implying that endoparasitism is a dead-end state for K. pedroana. Facultative parasitism in a free-living or an ectocommensal is uncommon and suggests a pathway to parasitism.

  8. Context-dependent species identity effects within a functional group of filter-feeding bivalves.

    Science.gov (United States)

    Vaughn, Caryn C; Spooner, Daniel E; Galbraith, Heather S

    2007-07-01

    We asked whether species richness or species identity contributed more to ecosystem function in a trait-based functional group, burrowing, filter-feeding bivalves (freshwater mussels: Unionidae), and whether their importance changed with environmental context and species composition. We conducted a manipulative experiment in a small river examining the effects of mussel assemblages varying from one to eight species on benthic algal standing crop across two sets of environmental conditions: extremely low discharge and high water temperature (summer); and moderate discharge and water temperature (fall). We found strong species identity effects within this guild, with one species (Actinonaias ligamentina) influencing accrual of benthic algae more than other species, but only under summer conditions. We suspect that this effect is due to a combination of the greater biomass of this species and its higher metabolic and excretion rates at warm summer temperatures, resulting in increased nitrogen subsidies to benthic algae. We also found that Actinonaias influenced the condition of other mussel species, likely through higher consumption, interference, or both. This study demonstrates that species within trait-based functional groups do not necessarily have the same effects on ecosystem properties, particularly under different environmental conditions.

  9. Biomarkers in the freshwater bivalve Corbicula fluminea confined downstream a domestic landfill leachate discharge.

    Science.gov (United States)

    de Oliveira, Luciana Fernandes; Santos, Caroline; Dos Reis Martinez, Claudia Bueno

    2016-07-01

    Landfills represent a severe environmental problem mainly due to the generation of leachates, and this study aimed to evaluate sublethal effects of a domestic landfill leachate in the freshwater bivalve Corbicula fluminea. Clams were submitted to in situ tests along a stream, at three sites, representing increasing distances from the leachate discharge (Pq1, Pq2, and Pq3), for 1, 5, and 15 days. The following biomarkers were analyzed in the gills and digestive glands: 7-ethoxyresorufin-O-deethylase (EROD) and glutathione S-transferase (GST) activities, multixenobiotic resistance mechanism (MXR), total antioxidant capacity (TAC), reactive oxygen species (ROS), and lipid peroxidation (LPO). Metallothionein (MT) content was determined in the gills and DNA damage in hemocytes. The mortality rate of animals during in situ tests was reduced as the distance from the leachate discharge source increased. On the other hand, biomarker results showed sublethal effects on C. fluminea confined at all sites of PqS. GST, TAC, ROS, and DNA damage were the most significant biomarkers for this species and should be considered for future monitoring and assessment of freshwater environments located in landfill areas.

  10. The unusual mineral vaterite in shells of the freshwater bivalve Corbicula fluminea from the UK

    Science.gov (United States)

    Spann, Nicole; Harper, Elizabeth M.; Aldridge, David C.

    2010-08-01

    Asian clams ( Corbicula fluminea) with abnormally thickened shell valves were found in four rivers in the UK (Rivers Yare, Waveney, Thames and New Bedford River). The material making up these malformations was the rare calcium carbonate polymorph vaterite. Vaterite is seldom found in the natural environment because it is less stable than the other calcium carbonate polymorphs (aragonite and calcite). In the few reported cases of vaterite formation in molluscs, it is usually related to unusual biomineralisation events such as shell regeneration, pearls and initial stages of shell formation. We compared two populations from the Rivers Yare and Waveney in the Norfolk Broads, UK, one (River Waveney) displaying dominantly the normal Corbicula shell form with aragonitic shells. In the River Yare population, all individuals sampled had shell deformations to different extents. These deformations were apparent as bulges on the inside of the ventral shell margin. X-ray diffraction confirmed that the shell material in the bulges of recently collected clams was vaterite. Other parts of the deformed shells were aragonitic. The shell deformations alter the shell morphology, leading to higher and wider shells. The shell microstructure is fibrous in the vateritic parts and crossed-lamellar in the aragonitic parts of deformed or non-deformed shells. The cause for the malformations is probably a disrupted biomineralisation process in the bivalves. Fossil Corbicula specimens from the late Pleistocene had similar deformations, suggesting that this is not a response to anthropogenic causes, such as pollution.

  11. Vibrio bivalvicida sp. nov., a novel larval pathogen for bivalve molluscs reared in a hatchery.

    Science.gov (United States)

    Dubert, Javier; Romalde, Jesús L; Prado, Susana; Barja, Juan L

    2016-02-01

    Three isolates were obtained from cultures of carpet shell clam (Ruditapes decussatus) reared in a bivalve hatchery (Galicia, NW Spain) from different sources: healthy broodstock, moribund larvae and the seawater corresponding to the larval tank. All isolates were studied by a polyphasic approach, including a phylogenetic analysis based on concatenated sequences of the five housekeeping genes ftsZ, gyrB, pyrH, recA and rpoA. The analysis supported their inclusion in the Orientalis clade of the genus Vibrio, and they formed a tight group separated from the closest relatives: Vibrio tubiashii subsp. europaensis, Vibrio tubiashii subsp. tubiashii and Vibrio orientalis. The percentages of genomic resemblance, including average nucleotide identity, DNA-DNA hybridization and in silico genome-to-genome comparison, between the type strain and the closest relatives were below values for species delineation and confirmed the taxonomic position of the new species, which could be differentiated from the related taxa on the basis of several phenotypic and chemotaxonomic features, including FAME and MALDI-TOF-MS. The pathogenicity of the new species was demonstrated in larvae of R. decussatus, Ruditapes philippinarum, Ostrea edulis and Donax trunculus. The results demonstrated that the strains analyzed represented a novel species in the Orientalis clade of the genus Vibrio, for which the name Vibrio bivalvicida sp. nov. is proposed, with 605(T) (= CECT 8855(T)=CAIM 1904(T)) designated as the type strain. Copyright © 2015 Elsevier GmbH. All rights reserved.

  12. THE EFFECTS OF HOST GENOTYPE AND SPATIAL DISTRIBUTION ON TREMATODE PARASITISM IN A BIVALVE POPULATION.

    Science.gov (United States)

    Grosholz, Edwin D

    1994-10-01

    A basic assumption underlying models of host-parasite coevolution is the existence of additive genetic variation among hosts for resistance to parasites. However, estimates of additive genetic variation are lacking for natural populations of invertebrates. Testing this assumption is especially important in view of current models that suggest parasites may be responsible for the evolution of sex, such as the Red Queen hypothesis. This hypothesis suggests that the twofold reproductive disadvantage of sex relative to parthenogenesis can be overcome by the more rapid production of rare genotypes resistant to parasites. Here I present evidence of significant levels of additive genetic variance in parasite resistance for an invertebrate host-parasite system in nature. Using families of the bivalve mollusc, Transennella tantilla, cultured in the laboratory, then exposed to parasites in the field, I quantified heritable variation in parasite resistance under natural conditions. The spatial distribution of outplanted hosts was also varied to determine environmental contributions to levels of parasite infection and to estimate potential interactions of host genotype with environment. The results show moderate but significant levels of heritability for resistance to parasites (h 2 = 0.36). The spatial distribution of hosts also significantly influenced parasite prevalence such that increased host aggregation resulted in decreased levels of parasite infection. Family mean correlations across environments were positive, indicating no genotype-environment interaction. Therefore, these results provide support for important assumptions underlying coevolutionary models of host-parasite systems. © 1994 The Society for the Study of Evolution.

  13. Physiological status and intersex in the endobenthic bivalve Scrobicularia plana from thirteen estuaries in northwest France

    International Nuclear Information System (INIS)

    Fossi Tankoua, O.; Amiard-Triquet, C.; Denis, F.; Minier, C.; Mouneyrac, C.; Berthet, B.

    2012-01-01

    The bivalve Scrobicularia plana, an important species for the structure and functioning of estuarine and coastal mudflats, was studied in thirteen sites from NW France differing by their degree of contamination to document the presence of reproduction impairments (intersex, sex ratio, gonadosomatic indices) in relation to the condition revealed by using hepatosomatic and condition indices. In agreement with recent studies in other European estuaries, intersex was revealed in all the studied estuaries, including sites the chemical and ecological status of which is considered “good” according to the criteria of the European Water Framework Directive. The presence of endocrine disrupting chemicals (EDCs) could result in such disturbances. Our results re-inforce the concern linked to the subtle effects of EDCs, which are active at very low doses, often in the absence of any major sign of toxicity. However at this stage, no clear link may be established between intersex and population effects. - Highlights: ► Clams were collected from 13 estuaries differing by their degree of contamination. ► Gonadosomatic, hepatosomatic and condition indices were determined. ► Reproduction impairments (intersex, biased sex ratio, asynchronism) were shown. ► Intersex shown even at sites with good ecological status (Water Framework Directive). ► No clear links between intersex and populational effects. - Intersex in clams from estuaries, the chemical/ecological status of which was considered as good under the EC Water Framework Directive.

  14. Antimicrobial resistance of Campylobacter species isolated from edible bivalve molluscs purchased from Bangkok markets, Thailand.

    Science.gov (United States)

    Soonthornchaikul, Nantika; Garelick, Hemda

    2009-10-01

    Campylobacter species have been recognized as the most commonly reported cause of bacterial gastroenteritis in humans. The increase of resistance rates to drugs of choice used for treatment in campylobacteriosis is becoming a public health concern. In parallel, the increased use of antimicrobials in aquaculture may lead to the emergence of resistant microorganisms and is likely to cause additional health risk to humans through food consumption. The study assesses the presence of antimicrobial resistance in Campylobacter species isolated from three groups of bivalve molluscs (bloody cockles, green mussels, and oysters) purchased from markets in Bangkok. Thirty samples were collected from each group. Susceptibility to three antimicrobials was determined using the Epsilometer test. Rates of erythromycin, nalidixic acid, and ciprofloxacin resistance in Campylobacter isolates were 72-84%, 28-40%, and 21-25%, respectively. There was no statistically significant difference in the prevalence of each antimicrobial resistance between the three groups. This study demonstrates a significant level of antimicrobial resistance in the Campylobacter spp. isolated from molluscs with a particular high rate of resistance to erythromycin. Consumption of raw molluscs contaminated with antimicrobial-resistant Campylobacter spp. may therefore result in resistant infections in humans.

  15. Effect of the alien invasive bivalve Corbicula fluminea on the nutrient dynamics under climate change scenarios

    Science.gov (United States)

    Coelho, J. P.; Lillebø, A. I.; Crespo, D.; Leston, S.; Dolbeth, M.

    2018-05-01

    The main aim of this study was to evaluate the impact of the alien invasive bivalve Corbicula fluminea (Müller, 1774) in the nutrient dynamics of temperate estuarine systems (oligohaline areas) under climate change scenarios. The scenarios simulated shifts in climatic conditions, following salinity (0 or 5) and temperature (24 or 30 °C) changes, usual during drought and heat wave events. The effect of the individual size/age (different size classes with fixed biomass) and density (various densities of <1 cm clams) on the bioturbation-associated nutrient dynamics were also evaluated under an 18-day laboratory experimental setup. Results highlight the significant effect of C. fluminea on the ecosystem nutrient dynamics, enhancing the efflux of both phosphate and dissolved inorganic nitrogen (DIN) from the sediments to the water column. Both drought and heat wave events will have an impact on the DIN dynamics within C. fluminea colonized systems, favouring a higher NH4-N efflux. The population structure of C. fluminea will have a decisive role on the impact of the species, with stronger nutrient effluxes associated with a predominantly juvenile population structure.

  16. Seasonal change in a filter-feeding bivalve Musculista senhousia population of a eutrophic estuarine lagoon

    Science.gov (United States)

    Yamamuro, Masumi; Hiratsuka, Jun'ichi; Ishitobi, Yu

    2000-10-01

    Filter-feeding bivalves often predominate the benthic biomass of estuaries, although their population size may drastically fluctuate due to physical and biological disturbances. To examine the recovery of a mussel population after periods of severe predation and anoxia, and to estimate the amount of nutrients removed from the system through mussel production, we surveyed, over 2 years, the Musculista senhousia population in the estuarine lagoon, Lake Nakaumi, Japan. Predation by diving ducks ( Aythya fuligula, Aythya ferina and Aythya marila) during winter dramatically reduced the mussel biomass in both years, but recruitment of juvenile mussels sustained the population. Anoxia during the second summer severely reduced the mussel population, resulting in less biomass than in the autumn of the previous year. Potential annual removal of nitrogen and phosphorus from the lagoon water through burial of M. senhousia shells under oxic conditions was estimated to be 7.1 and 5.1 tons, respectively. These are equivalent to 0.7% and 4.9% of the nitrogen and phosphorous annual load entering the lagoon via the main river. Under anoxic conditions, removal would decrease to only 5.6% of the potential amount.

  17. Marine Bacteria with antimicrobials capacity isolated from cultures of bivalve mollusks

    Directory of Open Access Journals (Sweden)

    Fabiola Pellon

    2014-06-01

    Full Text Available Microorganisms have commonly been studied as producers of antibacterial substances; yet they are also considered producers of antifungic, antiviral, antiparasitic, citotoxics and inhibitory of other forms of cellular growth substances. This paper describes the isolation, inhibitory potential and phenotipic characterization of native bacterial strains associated to bivalve mollusks such as Argopecten purpuratus “concha de abanico” and Crassostrea gigas “ostra” in cultivation systems. From 345 marine strains collected, 20 strains were recovered that had the ability of inhibiting a wide spectrum of fish, mollusks and shellfish pathogenic bacteria; being the most sensitive pathogens Aeromonas sobria P-281, Aeromonas hydrophila ATCC 7966, Vibrio vulnificus ATCC 27562 and Vibrio parahaemolyticus ATCC 17803. The phenotipic characterization of this strains with inhibitory capacity allowed the identification of the following genera: Vibrio (40%, Aeromonas (15%, Flavobacterium (10%, Pseudomonas (5%, Moraxella (5%, Flexibacter (5%. A 20% could not be identified. The results suggest that the isolated bacteria could be used as probiotics agents for the biological control of pathogens from marine organisms of interest in mariculture.

  18. Protandric hermaphroditism in the whale-fall bivalve mollusc Idas washingtonia

    Science.gov (United States)

    Tyler, Paul A.; Marsh, Leigh; Baco-Taylor, Amy; Smith, Craig R.

    2009-09-01

    Whale falls provide abundant but relatively ephemeral, sulphide-rich habitat islands on the deep-sea floor. To explore life-history adaptations to whale-fall habitats, we examined the reproductive biology of Idas washingtonia, a bathymodiolin mussel occurring in abundance on sunken whale skeletons in the deep northeast Pacific Ocean. Analysis of the reproductive biology of I. washingtonia demonstrates strong evidence of protandric hermaphroditism. Developing males were recognised in individuals as small as 1.7 mm shell length and spermatogenesis continued until ˜7 mm length. At >6.5 mm, males were generally spent and the first previtellogenic oocytes were observed. Although developing females were found as small as 4.5 mm shell length, most well-developed females were >6 mm shell length. Overall, females only formed ˜12% of the population. As with other modiolid bivalves, fecundity was high and the egg size whale falls even though these may have been severely reduced in abundance since the peak of commercial whaling activity in the 20th century.

  19. Clinical Manifestations of the Opiate Withdrawal Syndrome

    Directory of Open Access Journals (Sweden)

    Faniya Shigakova

    2015-09-01

    Full Text Available Currently, substance abuse is one of the most serious problems facing our society. The aim of this study was to investigate the clinical manifestations of the opiate withdrawal syndrome (OWS. The study included 112 patients (57 women and 55 men aged from 18 to 64 years with opium addiction according to the DSM-IV. To study the clinical manifestation of OWS, the special 25-score scale with four sections to assess severity of sleep disorders, pain syndrome, autonomic disorders, and affective symptoms was used. Given the diversity of the OWS symptoms, attention was focused on three clinical variants, affective, algic and mixed. The OWS affective variant was registered more frequently in women, while the mixed type of OWS was more typical of men.

  20. The chronic gastrointestinal manifestations of Chagas disease

    Directory of Open Access Journals (Sweden)

    Nilce Mitiko Matsuda

    2009-01-01

    Full Text Available Chagas disease is an infectious disease caused by the protozoan Trypanosoma cruzi. The disease mainly affects the nervous system, digestive system and heart. The objective of this review is to revise the literature and summarize the main chronic gastrointestinal manifestations of Chagas disease. The chronic gastrointestinal manifestations of Chagas disease are mainly a result of enteric nervous system impairment caused by T. cruzi infection. The anatomical locations most commonly described to be affected by Chagas disease are salivary glands, esophagus, lower esophageal sphincter, stomach, small intestine, colon, gallbladder and biliary tree. Chagas disease has also been studied in association with Helicobacter pylori infection, interstitial cells of Cajal and the incidence of gastrointestinal cancer.

  1. Antiphospholipid antibody: laboratory, pathogenesis and clinical manifestations

    Directory of Open Access Journals (Sweden)

    T. Ziglioli

    2011-06-01

    Full Text Available Antiphospholipid antibodies (aPL represent a heterogeneous group of antibodies that recognize various antigenic targets including beta2 glycoprotein I (β2GPI, prothrombin (PT, activated protein C, tissue plasminogen activator, plasmin and annexin A2. The most commonly used tests to detect aPL are: lupus anticoagulant (LAC, a functional coagulation assay, anticardiolipin antibody (aCL and anti-β2GPI antibody (anti-β2GPI, which are enzyme-linked immunoassay (ELISA. Clinically aPL are associated with thrombosis and/or with pregnancy morbidity. Apparently aPL alone are unable to induce thrombotic manifestations, but they increase the risk of vascular events that can occur in the presence of another thrombophilic condition; on the other hand obstetrical manifestations were shown to be associated not only to thrombosis but mainly to a direct antibody effect on the trophoblast.

  2. Clinical Manifestations and Diagnosis of Acromegaly

    Directory of Open Access Journals (Sweden)

    Gloria Lugo

    2012-01-01

    Full Text Available Acromegaly and gigantism are due to excess GH production, usually as a result of a pituitary adenoma. The incidence of acromegaly is 5 cases per million per year and the prevalence is 60 cases per million. Clinical manifestations in each patient depend on the levels of GH and IGF-I, age, tumor size, and the delay in diagnosis. Manifestations of acromegaly are varied and include acral and soft tissue overgrowth, joint pain, diabetes mellitus, hypertension, and heart and respiratory failure. Acromegaly is a disabling disease that is associated with increased morbidity and reduced life expectancy. The diagnosis is based primarily on clinical features and confirmed by measuring GH levels after oral glucose loading and the estimation of IGF-I. It has been suggested that the rate of mortality in patients with acromegaly is correlated with the degree of control of GH. Adequately treated, the relative mortality risk can be markedly reduced towards normal.

  3. [Neurological manifestations in atypical Kawasaki disease].

    Science.gov (United States)

    Martínez-Guzmán, Edgar; Gámez-González, Luisa Berenise; Rivas-Larrauri, Francisco; Sorcia-Ramírez, Giovanni; Yamazaki-Nakashimada, Marco

    2017-01-01

    Kawasaki disease (KD) is a type of systemic vasculitis of unknown etiology. Atypical Kawasaki disease is defined as that where there are signs and symptoms not corresponding to the classical criteria for this nosological entity. Children with atypical Kawasaki disease may present with acute abdominal symptoms, meningeal irritation, pneumonia or renal failure. We describe 4 children with ages ranging from 2 to 12 years who had atypical Kawasaki disease, with neurological and gastrointestinal symptoms as part of the systemic presentation of the disease. Treatment consisted of immunoglobulin and corticosteroids with good evolution. KD is a systemic vasculitis that can involve many territories. Atypical manifestations can mislead the clinician and delay diagnosis. Pediatricians and sub-specialists should be aware of these neurological manifestations in order to provide adequate and opportune treatment.

  4. Acute dacryocystitis: another clinical manifestation of sporotrichosis

    Directory of Open Access Journals (Sweden)

    Dayvison Francis Saraiva Freitas

    2014-04-01

    Full Text Available Sporotrichosis associated with exposure to domestic cats is hyperendemic in Rio de Janeiro, Brazil. A review of the clinical records at our institute revealed four patients with clinical signs of dacryocystitis and a positive conjunctival culture for Sporothrix who were diagnosed with Sporothrix dacryocystitis. Three patients were children (< 13 years of age and one patient was an adult. Two patients reported contact with a cat that had sporotrichosis. Dacryocystitis was associated with nodular, ulcerated lesions on the face of one patient and with granulomatous conjunctivitis in two patients; however, this condition manifested as an isolated disease in another patient. All of the patients were cured of the fungal infections, but three patients had chronic dacryocystitis and one patient developed a cutaneous fistula. Sporotrichosis is usually a benign disease, but may cause severe complications when the eye and the adnexa are affected. Physicians, especially ophthalmologists in endemic areas, should be aware of the ophthalmological manifestations and complications of sporotrichosis.

  5. Pulmonary Paraganglioma Manifesting as an Endobronchial Mass

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Nam; Lee, Ki Nam; Roh, Mee Sook; Choi, Pil Jo; Yang, Doo Kyung [College of Medicine, Dong-A University, Pusan (Korea, Republic of)

    2008-02-15

    The thoracic manifestations of paragangliomas include well-enhancing mediastinal masses, metastatic parenchymal nodules, lymphadenopathy from malignant paragangliomas, and pulmonary edema as a complication of epinephrine-producing paragangliomas. The much less common manifestations include a primary mass in the lung, heart, esophagus and/or trachea. Primary pulmonary paraganglioma was first reported by Heppleston in 1958, and only 19 cases have been reported since then in the English literature. Three of these cases were malignancies with lymph nodes metastases. In the remaining cases, the lesions behaved in a benign manner. The patients are usually female and in their middle age. Most patients are free of symptoms and hypertension, and the tumors are often discovered incidentally on routine chest radiographs.

  6. [Cerebrotendinous xanthomatosis: physiopathology, clinical manifestations and genetics].

    Science.gov (United States)

    Preiss, Yudith; Santos, José L; Smalley, Susan V; Maiz, Alberto

    2014-05-01

    Cerebrotendinous xanthomatosis (CTX) is a rare autosomal recessive disease, caused by genetic deficiency of the 27-hydroxylase enzyme (encoded by CYP27A1). It plays a key role in cholesterol metabolism, especially in bile acid synthesis and in the 25-hydroxylation of vitamin D3 in the liver. Its deficiency causes reduced bile acid synthesis and tissue accumulation of cholestanol. Clinical manifestations are related to the presence of cholestanol deposits and include tendon xanthomas, premature cataracts, chronic diarrhea, progressive neurologic impairment and less frequently coronary heart disease, early onset osteoporosis and abnormalities in the optic disk and retina. An early diagnosis and treatment with quenodeoxycholic acid may prevent further complications, mainly neurological manifestations. This review summarizes cholesterol metabolism related to bile acid synthesis, physiopathology, biochemistry and treatment of cerebrotendinous xanthomatosis.

  7. Ocular manifestations of leukaemia in Ethiopians.

    Science.gov (United States)

    Alemayehu, W; Shamebo, M; Bedri, A; Mengistu, Z

    1996-10-01

    A prospective ophthalmic evaluation of 74 newly diagnosed and 34 old (on follow-up) leukaemic patients, carried out from March 1990 to December 1995 is described. Primary ocular involvement, that is leukaemic retinal infiltrates, were detected in 32% of the newly diagnosed. In contrast, none of the old leukaemic patients had this lesion. In 69% of the new and 21% of the old cases, secondary ocular manifestations of leukaemia were observed. The major secondary ocular manifestation of leukaemia in both groups was intra-retinal haemorrhage. A variety of miscellaneous ocular findings, such as cataract, pterygium, pingeculae, etc. were detected in 36% of all leukemics. These findings indicate the importance of a complete ophthalmologic evaluation in the diagnosis, follow-up and management of leukaemic patients.

  8. Pattern of cutaneous manifestations in diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Goyal Abhishek

    2010-01-01

    Full Text Available Background: Diabetes mellitus affects individuals of all ages and socioeconomic status. Skin is affected by the acute metabolic derangements as well as by chronic degenerative complications of diabetes. Aims: To evaluate the prevalence of skin manifestations in patients with diabetes mellitus. To analyze the prevalence and pattern of skin disorders among diabetic patients from this region of Western Himalayas. Materials and Methods: One hundred consecutive patients with the diagnosis of diabetes mellitus and having skin lesions, either attending the diabetic clinic or admitted in medical wards were included in this study. Results: The common skin disorders were: x0 erosis (44%, diabetic dermopathy (36%, skin tags (32%, cutaneous infections (31%, and seborrheic keratosis (30%. Conclusion: Skin is involved in diabetes quite often and the manifestations are numerous. High prevalence of xerosis in our diabetic population is perhaps due to cold and dry climatic conditions in the region for most of the time in the year.

  9. ORAL MANIFESTATIONS AMONG ROMANIAN HIV PATIENTS

    Directory of Open Access Journals (Sweden)

    Manuela ARBUNE

    2013-03-01

    Full Text Available The objective of the study is to evaluate the oral health problems on HIV youth patients from Galati. Materials and method. A cross-sectional study assessed 102 patients with mean age 22. The most frequent oral manifestations on HIV infected youth under ART are erythema marginatum, periodontitis, candidosis and hypertrophia gingivalis. Results and discussion. Dental decay-missing-filled index on HIV patients is high. Viral HIV replication, long time pediatric exposure on HIV, male sex, smoking, and oral inflamation are related to dental poor condition. Exodontic therapy is comon among HIV youth. However, persistence of some associated oral infections is related to individual or behavioral risk factors, but also to some newly found mechanisms, such as disfunctional immune reconstruction. Seeing to antiretroviral treatment, the severity and frequency of oral manifestations decreased among HIV patients on antiretroviral treatment. Conclusions. Developing medical, social and educational programs is imperative for improving the oral health of HIV youth of Galati.

  10. Near infra-red spectroscopy quantitative modelling of bivalve protein, lipid and glycogen composition using single-species versus multi-species calibration and validation sets

    Science.gov (United States)

    Bartlett, Jill K.; Maher, William A.; Purss, Matthew B. J.

    2018-03-01

    Near infrared spectroscopy (NIRS) quantitative modelling was used to measure the protein, lipid and glycogen composition of five marine bivalve species (Saccostrea glomerata, Ostrea angasi, Crassostrea gigas, Mytilus galloprovincialis and Anadara trapezia) from multiple locations and seasons. Predictive models were produced for each component using individual species and aggregated sample populations for the three oyster species (S. glomerata, O. angasi and C. gigas) and for all five bivalve species. Whole animal tissues were freeze dried, ground to > 20 μm and scanned by NIRS. Protein, lipid and glycogen composition were determined by traditional chemical analyses and calibration models developed to allow rapid NIRS-measurement of these components in the five bivalve species. Calibration modelling was performed using wavelet selection, genetic algorithms and partial least squares analysis. Model quality was assessed using RPIQ and RMESP. For protein composition, single species model results had RPIQ values between 2.4 and 3.5 and RMSEP between 8.6 and 18%, the three oyster model had an RPIQ of 2.6 and an RMSEP of 10.8% and the five bivalve species had an RPIQ of 3.6 and RMSEP of 8.7% respectively. For lipid composition, single species models achieved RPIQ values between 2.9 and 5.3 with RMSEP between 9.1 and 11.2%, the oyster model had an RPIQ of 3.6 and RMSEP of 6.8 and the five bivalve model had an RPIQ of 5.2 and RMSEP of 6.8% respectively. For glycogen composition, the single species models had RPIQs between 3.8 and 18.9 with RMSEP between 3.5 and 9.2%, the oyster model had an RPIQ of 5.5 and RMSEP of 7.1% and the five bivalve model had an RPIQ of 4 and RMSEP of 7.6% respectively. Comparison between individual species models and aggregated models for three oyster species and five bivalve species for each component indicate that aggregating data from like species produces high quality models with robust and reliable quantitative application. The benefit of

  11. Unusual roentgenologic manifestations of Meckel's diverticulum

    International Nuclear Information System (INIS)

    Miller, K.B.; Naimark, A.; O'Connor, J.F.; Bouras, L.

    1981-01-01

    Five cases illustrating rare roentgenographic manifestations of Meckel's diverticulum are presented. Small bowel studies in 2 patients demonstrated a mucosal pattern identifiable as heterotopic gastric rugae, and in 2 other cases peptic ulcers were seen within the diverticulum. In 1 patient the diverticulum located in the right upper quadrant contained calcified enteroliths, and in another patient the diverticulum had fistulous communication with the appendix. (orig.)

  12. The radiological manifestations of sickle cell disease

    Energy Technology Data Exchange (ETDEWEB)

    Madani, G. [Department of Radiology, Royal Free Hospital NHS Trust, London (United Kingdom)]. E-mail: gittamadani@yahoo.com; Papadopoulou, A.M. [Department of Radiology, Royal Free Hospital NHS Trust, London (United Kingdom); Holloway, B. [Department of Radiology, Royal Free Hospital NHS Trust, London (United Kingdom); Robins, A. [Department of Paediatrics, Whittington Hospital NHS Trust, London (United Kingdom); Davis, J. [Department of Radiology, Whittington Hospital NHS Trust, London (United Kingdom); Murray, D. [Department of Radiology, Whittington Hospital NHS Trust, London (United Kingdom)

    2007-06-15

    Sickle cell disease (SCD) is an inherited abnormality of the ss-globin chain, which causes a spectrum of haemolytic anaemias. Clinical manifestations in SCD include anaemia, jaundice, recurrent vaso-occlusive crises, and infections (particularly by encapsulated bacteria) due to functional asplenia and cerebrovascular accidents. Radiological investigations play a critical role both in the diagnosis and in the primary prevention of the complications of SCD.

  13. Atypical manifestations of multiple myeloma: Radiological appearance

    International Nuclear Information System (INIS)

    Hess, Thomas; Egerer, Gerlinde; Kasper, Bernd; Rasul, Kakil Ibrahim; Goldschmidt, Hartmut; Kauffmann, G.W.

    2006-01-01

    Diagnostic procedures performed on patients with multiple myeloma typically reveal lytic bone lesions, osteopenia or osteoporosis, bone marrow infiltration by plasma cells as well as overproduction of immunoglobulin or light chains in the serum or urine. Skeletal manifestations are extremely variable and the unusual forms have been described extensively. Extramedullary plasma-cell tumours (plasmocytoma) are found in about 5% of newly diagnosed patients with multiple myelomas. In this paper we present eight patients with atypical forms of multiple myeloma

  14. A rare manifestation of tuberculosis: Scrofuloderma

    Directory of Open Access Journals (Sweden)

    Savaş Öztürk

    2011-03-01

    Full Text Available Scrofuloderma is a cutaneous manifestation of tuberculosis that results from direct extension of an underlying tuberculous focus, such as lymph node to the overlying skin. In this article, 16-year-old male patient, live in a child detention home, with a purulent, ulcerated lesion in his neck, diagnosed as Scrofuloderma was presented. The case presented in order to stress that Scrofuloderma, a rare form of tuberculosis, should be kept in mind in the differential diagnosis of chronic skin lesions.

  15. Les manifestations cardiovasculaires chez les hemodialyses ...

    African Journals Online (AJOL)

    Le but de l'étude est d'analyser sur une période de 12 mois chez 75 patients en hémodialyse chronique, âgés de 38ans en moyenne, le les aspects cliniques, thérapeutiques et évolutifs des manifestations cardiovasculaires. La prévalence est de 87,20% chez les patients. Les signes fonctionnels les plus fréquents sont la ...

  16. Cardiac manifestations of Familial Mediterranean fever

    OpenAIRE

    Alsarah, Ahmad; Alsara, Osama; Laird-Fick, Heather S.

    2017-01-01

    Familial Mediterranean fever (FMF) is autoinflammatory disorder characterized by sporadic attacks of fever, peritonitis, pleuritis, and arthritis. It is mainly seen in patients from Mediterranean origins, but it is now reported more frequently in Europe and North America due to immigration. To analyze the data on the cardiovascular manifestations in FMF patients, we searched PubMed using the terms “Familial Mediterranean Fever” or “FMF” in combination with other key words including “cardiovas...

  17. Mucocutaneous manifestations of cocaine abuse: a review.

    Science.gov (United States)

    Moreno-Artero, Ester; Querol-Cisneros, Elena; Rodríguez-Garijo, Nuria; Tomás-Velázquez, Alejandra; Antoñanzas, Javier; Fernández, Secundino; Gil-Sánchez, María Pilar; España, Agustín

    2018-03-06

    Cocaine is an alkaloid extracted from the leaves of the Erythroxylum coca plant that emerged in the 1970s as a fashionable drug among members of certain social backgrounds. Cocaine abuse is a problem of current interest, which is mostly hidden and under-diagnosed, but dramatically widespread among all socioeconomic strata, and with an incidence which is increasing at an alarming rate. There are 1.5 million cocaine consumers in the USA. In Spain, the prevalence of consumption among the population between 15 and 65 years-old is higher, reaching 3.1%. Because of this, it seems important to understand and recognize all the mucocutaneous manifestations of cocaine abuse which have been reported in the literature in order to clarify and help dermatologists in their daily practice. In this article, we describe the principal mucocutaneous manifestations of cocaine abuse and we review isolated case reports which have been published in the literature. Because the dermatologist may deal with an unknown problem as well as with an already well-known history of cocaine abuse, it seems logical to separate the mucocutaneous manifestations into those which are frequent and highly suggestive, such as those caused by vascular injury, damage to mucosal membranes, infectious diseases or neutrophilic dermatosis, especially when suffered by young people and in consonance with other systemic manifestations and, those which have been reported in the literature as isolated case reports. We also summarize the main aspects of its pathogeny, principal pharmacodynamic and pharmacokinetic characteristics, and diagnostic tools. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  18. Manifestation of contagious bovine pleuropneumonia in seven ...

    African Journals Online (AJOL)

    The aim of this study was to assess effects of CBPP in 7-month-old calves following infection by in-contact transmission; and manifestation in adult cattle and ... Les résultats montrent que les veaux de 7 mois, qu'ils soient infectés par intubation ou par contact, développent des signes respiratoires similaires à ceux des ...

  19. Palmse viinaköögi manifest

    Index Scriptorium Estoniae

    1996-01-01

    Manifest. Tõlkijate seminari puhul 17. mail 1996 Palmse viinaköögis Juta Bedia, Eric Dickens, Gyözö Fehérvári, Guntars Godinsh, Maima Grinberga, Irja Grönholm, Leif Hannibal, Cornelius Hasselblatt, Pirkko Huurto, Ivo Iliste, Nora Javorskaja, Gisbert Jänicke, Kaisu Lahikainen, Enel Melberg, Vera Ruber, Arnold Tamm, Leili Tamm, Jonatan Tomesh, Lilia Velic'kova, Marianne Vogel. Inglise k.: Estonian Literary Magazine, autumn 1996, nr. 3

  20. Cutaneous Manifestations of Systemic Lupus Erythematosus

    OpenAIRE

    Uva, Luís; Miguel, Diana; Pinheiro, Catarina; Freitas, João Pedro; Marques Gomes, Manuel; Filipe, Paulo

    2012-01-01

    Systemic lupus erythematosus (SLE) is a multiorgan autoimmune disease of unknown etiology with many clinical manifestations. The skin is one of the target organs most variably affected by the disease. The American College of Rheumatology (ACR) established 11 criteria as a classificatory instrument to operationalise the definition of SLE in clinical trials. They were not intended to be used to diagnose individuals and do not do well in that capacity. Cutaneous lesions account for four of these...

  1. Dermatological manifestations of chronic renal failure

    Directory of Open Access Journals (Sweden)

    Tawade Y

    1996-01-01

    Full Text Available Dermatological manifestations of chronic renal failure were studied in 35 cases. Xerosis was seen in 16 cases. Pruritus was observed in 12 cases and hyperpigmentation on exposed areas was seen in 8 patients. Acquired perforating disorder and half and half nail were seen in 6 cases each. Skin Biopsies performed in 6 cases of APD showed typical changes only in 3 cases.

  2. ORAL MANIFESTATIONS AMONG ROMANIAN HIV PATIENTS

    OpenAIRE

    Manuela ARBUNE; Oana-Mirela POTÂRNICHIE; Silvia MARTU

    2013-01-01

    The objective of the study is to evaluate the oral health problems on HIV youth patients from Galati. Materials and method. A cross-sectional study assessed 102 patients with mean age 22. The most frequent oral manifestations on HIV infected youth under ART are erythema marginatum, periodontitis, candidosis and hypertrophia gingivalis. Results and discussion. Dental decay-missing-filled index on HIV patients is high. Viral HIV replication, long time pediatric exposu...

  3. [Osteo-articular manifestations after suppurative pancreatitis].

    Science.gov (United States)

    Mateş, I N; Dinu, Daniela; Lupu, Amelia; Popescu, Luminiţa; Bălănescu, Andra; Constantinoiu, S

    2003-01-01

    Osseous and joint manifestations (decalcification, osteolysis, osteonecrosis; poliarthrytis; periarticular fat necrosis) are sometimes encountered in chronic pancreatitis or carcinoma, but exceptional after severe acute pancreatitis, especially infected pancreatic necrosis. Pathogenesis of calcium deficiency in acute pancreatitis is multifactorial, including extensive lipolysis and metabolic disturbances. We report on a healthy, young male, that developed decalcification and polyarthritis consecutive to a long-outcome, severe acute pancreatitis. We comment upon hypocalcemia, as a rare complication of acute pancreatitis.

  4. Abdominal manifestations of cystic fibrosis in children

    International Nuclear Information System (INIS)

    Chaudry, Gulraiz; Navarro, Oscar M.; Levine, Daniel S.; Oudjhane, Kamaldine

    2006-01-01

    Pulmonary complications remain the main cause of mortality in cystic fibrosis, but the presenting symptoms in children are often related to gastrointestinal or pancreaticobiliary disease. Furthermore, abdominal manifestations are now seen throughout childhood, from infancy to adolescence. The child might present in the neonatal period with meconium ileus or its attendant complications. The older child might present with distal intestinal obstruction syndrome or colonic stricture secondary to high doses of pancreatic enzyme replacement. Less-common gastrointestinal manifestations include intussusception, duodenitis and fecal impaction of the appendix. Most children also show evidence of exocrine pancreatic deficiency. Radiologically, the combination of fat deposition and pancreatic fibrosis leads to varying CT and MR appearances. A higher than normal incidence of pancreatic cysts and calcification is also seen. Decreased transport of water and chloride also increases the viscosity of bile, with subsequent obstruction of the biliary ductules. If extensive, this can progress to obstructive cirrhosis, portal hypertension and esophageal varices. Diffuse fatty infiltration, hypersplenism and gallstones are also commonly seen in these patients. We present a pictorial review of the radiological appearance of these abdominal manifestations. The conditions are dealt with individually, together with typical appearances in various imaging modalities. (orig.)

  5. Abdominal manifestations of cystic fibrosis in children

    Energy Technology Data Exchange (ETDEWEB)

    Chaudry, Gulraiz; Navarro, Oscar M.; Levine, Daniel S.; Oudjhane, Kamaldine [University of Toronto, Department of Diagnostic Imaging, Hospital for Sick Children, Toronto, ON (Canada)

    2006-03-15

    Pulmonary complications remain the main cause of mortality in cystic fibrosis, but the presenting symptoms in children are often related to gastrointestinal or pancreaticobiliary disease. Furthermore, abdominal manifestations are now seen throughout childhood, from infancy to adolescence. The child might present in the neonatal period with meconium ileus or its attendant complications. The older child might present with distal intestinal obstruction syndrome or colonic stricture secondary to high doses of pancreatic enzyme replacement. Less-common gastrointestinal manifestations include intussusception, duodenitis and fecal impaction of the appendix. Most children also show evidence of exocrine pancreatic deficiency. Radiologically, the combination of fat deposition and pancreatic fibrosis leads to varying CT and MR appearances. A higher than normal incidence of pancreatic cysts and calcification is also seen. Decreased transport of water and chloride also increases the viscosity of bile, with subsequent obstruction of the biliary ductules. If extensive, this can progress to obstructive cirrhosis, portal hypertension and esophageal varices. Diffuse fatty infiltration, hypersplenism and gallstones are also commonly seen in these patients. We present a pictorial review of the radiological appearance of these abdominal manifestations. The conditions are dealt with individually, together with typical appearances in various imaging modalities. (orig.)

  6. Chronic polyarthritis as isolated manifestation of toxocariasis.

    Science.gov (United States)

    Viola, Gabriela R; Giacomin, Maria Fernanda A; França, Camila M P; Sallum, Adriana M E; Jacob, Cristina M A; Silva, Clovis A

    2016-01-01

    Human toxocariasis is a parasitic zoonosis mainly caused by Toxocara canis or Toxocara cati and is acquired by ingestion of the parasite's embryonated eggs. Arthralgia and/or arthritis were reported in up to 17% of the cases, generally with acute duration (less than 6 weeks). However, to our knowledge, chronic polyarthritis, as the isolated presentation of Toxocara infection, was not reported. One of the 5809 patients that was followed up at our service (0.017%) had chronic polyarthritis as the single manifestation of toxocariasis and was described herein. A 3-year-old girl was referred to our service with severe painful chronic polyarthritis for a period longer than 10 weeks and morning stiffness of 30min. Dog contact exposure history in the recreational areas of neighborhood was reported. Her exams showed high levels of eosinophils in peripheral blood (29%), bone marrow aspirate revealed marked eosinophilia (32%) and Toxocara enzyme-linked immunosorbent assay (Elisa) was positive (1:1280). She was treated with paracetamol (40mg/kg/day) and thiabendazole (25mg/kg/day) for 10 days, and all manifestations reduced. After eight months of follow-up, she was on clinical and laboratorial remission. In conclusion, we described a case of chronic polyarthritis, as isolated manifestation of toxocariasis, mimicking juvenile idiopathic arthritis and leukemia. Importantly, this zoonosis should be considered in patients with arthritis and eosinophilia. Copyright © 2014 Elsevier Editora Ltda. All rights reserved.

  7. Species composition, richness, and distribution of marine bivalve molluscs in Bahía de Mazatlán, México.

    Science.gov (United States)

    Esqueda-González, María Del Carmen; Ríos-Jara, Eduardo; Galván-Villa, Cristian Moises; Rodríguez-Zaragoza, Fabian Alejandro

    2014-01-01

    We describe the composition and distribution of bivalve molluscs from the sandy and rocky intertidal and the shallow subtidal environments of Bahía de Mazatlán, México. The bivalve fauna of the bay is represented by 89 living species in 28 families, including 37 new records and four range extensions: Lithophaga hastasia, Adula soleniformis, Mactrellona subalata, and Strigilla ervilia. The number of species increases from the upper (44) and lower intertidal (53) to the shallow subtidal (76), but only 11 (17%) have a wide distribution in the bay (i.e., found in all sampling sites and environments). The bivalve assemblages are composed of four main life forms: 27 epifaunal species, 26 infaunal, 16 semi-infaunal, and 20 endolithic. A taxonomic distinctness analysis identified the sampling sites and environments that contribute the most to the taxonomic diversity (species to suborder categories) of the bay. The present work increased significantly (31%) to 132 species previous inventories of bivalves of Bahía de Mazatlán. These species represent 34% of the bivalve diversity of the southern Golfo de California and approximately 15% of the Eastern Tropical Pacific region.

  8. Cutaneous Manifestations in Renal Transplant Recipients

    Directory of Open Access Journals (Sweden)

    Fatma Elif Demirgüneş

    2008-05-01

    Full Text Available Background and Design: This study is designed to determine the prevalence and the clinical spectrum of skin diseases in renal transplant recipients (RTRs.Material and Method: In this study RTRs who were referred to our department between 2005 and 2007 for dermatologic examination were evaluated. Dermatologic investigation included direct clinical observation and culture or histolopathological investigation when indicated. Patients were divided into three groups: group A, post-transplantation periods £1 year; group B, post-transplantation periods of 1-5 years; and group C, post-transplantation periods >5 years. Results: In this study 88 (M=50, F=38 RTRs were evaluated. The mean age was 37 ± 12 years and the median interval since transplantation was 38.5 months (range=1 month-27 years. Over a 2-year period 298 cutaneous manifestations were identified. Ninety-five immunosuppressive (IS drug-related manifestations were observed in 58 (%65.9 patients and the most common one was acneiform eruption (n=23. Forty (45.5% patients developed cutaneous viral infections, consisting of verruca vulgaris (n=29, herpes zoster (n=9, herpes simplex (n=5, molluscum (n=2 and varicella (n=1 infections. Superficial fungal infections were observed in 35(39.2% patients, most common lesions were dermatophytosis (n = 23 and pityriasis versicolor (n=17. Bacterial infections were observed in 14 (%16 patients, folliculitis was present in 12 of them. Premalignant and malignant lesions were identified in 12 (%13.6 patients, consisting of actinic keratoses (n=9, basal cell carcinoma (n=2, squamous cell carcinoma (n=1 and Kaposi's sarcoma (n=1. There were more premalignant and malignant lesions in patients receiving azathioprine (p=0.002. Cutaneous viral infections were more common in group C (p=0.023 and IS drug-related manifestations were more common in group A (p=0.003. Conclusion: Most common cutaneous manifestation among RTRs was IS drug-related and seen in early post

  9. Gastrointestinal manifestations in systemic lupus erythematosus.

    Science.gov (United States)

    Fawzy, M; Edrees, A; Okasha, H; El Ashmaui, A; Ragab, G

    2016-11-01

    Systemic lupus erythematosus (SLE) is an autoimmune disorder characterized by multisystem involvement, including the gastrointestinal (GI) tract. There is a significant variation in the clinical presentation and severity of GI disorders. When GI symptoms present as the initial manifestation of SLE, there is likely to be a delay in the diagnosis. The cause of these GI manifestations in SLE may be the disease, or the side effects of medications, or infections. In this study we investigated the GI manifestations in a group of SLE patients. Our study was conducted on 40 SLE patients and 30 healthy controls to assess the prevalence of GI symptoms in SLE patients. The prevalence of gastrointestinal manifestations in our study was 42.5%. GI manifestations in our SLE patients were: acute abdominal pain (due to pleurisy and peritonitis), 6%; diffuse abdominal pain, 23.5%; epigastric pain, 29%; epigastric pain with vomiting, 23.5%; epigastric pain with chronic constipation, 6%; chronic constipation, 6%; and diffuse abdominal pain with bleeding per rectum, 6%. In our study, we found a higher incidence of Giardia infestation in SLE patients than in healthy controls, and 10% of these patients were asymptomatic. There was more Giardia infestation in patients with GI symptoms as compared with patients with no GI symptoms, with a P value of 0.009. In our study SLE patients with GI symptoms had a peak systolic velocity (cm/s) with a mean of 108.4 ± 32.1 standard deviation (SD) in the celiac Doppler study. Patients without GI symptoms had a peak systolic velocity with a mean of 111.9 ± 37.7 SD, meaning that our patients mostly had no evidence of celiac trunk stenosis, but there was significant difference between SLE patients without GI symptoms and controls, as the mean was higher in SLE patients than in the controls. Also, the celiac end diastolic velocity was higher in both groups of SLE patients with GI symptoms and those without GI symptoms, compared to controls.

  10. Molluscs for Sale: Assessment of Freshwater Gastropods and Bivalves in the Ornamental Pet Trade.

    Science.gov (United States)

    Ng, Ting Hui; Tan, Siong Kiat; Wong, Wing Hing; Meier, Rudolf; Chan, Sow-Yan; Tan, Heok Hui; Yeo, Darren C J

    2016-01-01

    The ornamental pet trade is often considered a key culprit for conservation problems such as the introduction of invasive species (including infectious diseases) and overharvesting of rare species. Here, we present the first assessment of the biodiversity of freshwater molluscs in the ornamental pet trade in Singapore, one of the most important global hubs of the ornamental aquarium trade, and discuss associated conservation concerns. We recorded freshwater molluscs from ornamental pet shops and major exporters including non-ornamental species (e.g., hitchhikers, molluscs sold as fish feed). We recorded an unexpectedly high diversity-59 species-of freshwater bivalves and gastropods, with the majority (38 species or 64%) being from the Oriental region. In addition to morphological examination, we sequenced the DNA barcode region of mitochondrial CO1 and 16S genes to provide molecular data for the confirmation of the identification and for future re-identification. DNA barcodes were obtained for 50 species, and all but four were separated by > 3% uncorrected pairwise distances. The trade has been considered a main introduction pathway for non-native species to Singapore, and we found that out of 15 species in the trade as well as in the wild in Singapore, 12 are either introduced or of unknown origin, representing almost half of the known non-native freshwater molluscs in Singapore. Particularly prevalent are non-ornamental species: six hitchhikers on aquarium plants and six species sold as fish feed. We found that a quarter of the trade species have a history of introduction, which includes 11 known or potentially invasive species. We conclude that potential overharvesting is difficult to assess because only half of the trade species have been treated by IUCN. Of these, 21 species are of Least Concern and three are Data Deficient. Our checklist, with accompanying DNA barcodes, images, and museum vouchers, provides an important reference library for future monitoring

  11. Morphological and chemical characterization of mineral concretions in the freshwater bivalve Anodonta cygnea (Unionidae).

    Science.gov (United States)

    Hinzmann, Mariana F; Lopes-Lima, Manuel; Bobos, Iulius; Ferreira, Jorge; Domingues, Bernardo; Machado, Jorge

    2015-01-01

    The freshwater mussel Anodonta cygnea is commonly used as a model organism for biomineralization studies, its peculiar morphofunctional properties also make it an excellent environmental biomonitor. The first detailed on the calcareous concretions from gill and mantle tissue, as well as fluids of the freshwater bivalve A. cygnea, supported by histological, scanning, spectrometry, and spectroscopy analyses. Through these analyses, the morphology, structure, and chemical characterization of these biomineral concretions were accomplished. The concretions represent a high percentage of the dry weight of these organisms. In gill tissue, it can reach up to 50% of dry weight prior to reproductive maturity. Analysis of elemental composition of the tissue concretions showed the presence of calcium and phosphate, as main components, associated with other residual elements like iron, manganese, magnesium, and zinc. Concretions are arranged in concentric alternated layers of organic and inorganic matrix. The shape and size of the concretions vary substantially, from very small, less than 1 μm diameter with very regular round structure, found mainly in the mantle tissue, to more than 50 μm length with irregular globular clusters, found predominantly in the gills. The microstructural organization is of a hydroxyapatite polymorphism in the mantle, in contrast to the gills, which exhibit irregular structure and carbonated hydroxyapatite polymorphism. These differences are supported by higher contents of dinitrogen pentoxide, magnesium, and iron in the mantle concretions, but higher contents of manganese and zinc in the gills. Furthermore, the results indicate that the mineral concretion formation in A. cygnea is a hemocytes reaction to particle or toxic invasions. A second relevant role, concerns the close involvement of these microspherules on the adult and larval shell calcification. © 2014 Wiley Periodicals, Inc.

  12. Genetic connectivity between north and south Mid-Atlantic Ridge chemosynthetic bivalves and their symbionts.

    Directory of Open Access Journals (Sweden)

    Karina van der Heijden

    Full Text Available Transform faults are geological structures that interrupt the continuity of mid-ocean ridges and can act as dispersal barriers for hydrothermal vent organisms. In the equatorial Atlantic Ocean, it has been hypothesized that long transform faults impede gene flow between the northern and the southern Mid-Atlantic Ridge (MAR and disconnect a northern from a southern biogeographic province. To test if there is a barrier effect in the equatorial Atlantic, we examined phylogenetic relationships of chemosynthetic bivalves and their bacterial symbionts from the recently discovered southern MAR hydrothermal vents at 5°S and 9°S. We examined Bathymodiolus spp. mussels and Abyssogena southwardae clams using the mitochondrial cytochrome c oxidase subunit I (COI gene as a phylogenetic marker for the hosts and the bacterial 16S rRNA gene as a marker for the symbionts. Bathymodiolus spp. from the two southern sites were genetically divergent from the northern MAR species B. azoricus and B. puteoserpentis but all four host lineages form a monophyletic group indicating that they radiated after divergence from their northern Atlantic sister group, the B. boomerang species complex. This suggests dispersal of Bathymodiolus species from north to south across the equatorial belt. 16S rRNA genealogies of chemoautotrophic and methanotrophic symbionts of Bathymodiolus spp. were inconsistent and did not match the host COI genealogy indicating disconnected biogeography patterns. The vesicomyid clam Abyssogena southwardae from 5°S shared an identical COI haplotype with A. southwardae from the Logatchev vent field on the northern MAR and their symbionts shared identical 16S phylotypes, suggesting gene flow across the Equator. Our results indicate genetic connectivity between the northern and southern MAR and suggest that a strict dispersal barrier does not exist.

  13. Revision of the Late Permian Non-Marine Bivalve Genus Verneuilunio Starobogatov, 1987

    Directory of Open Access Journals (Sweden)

    M.N. Urazaeva

    2015-03-01

    Full Text Available The genus Verneuilunio (type species Naiadites verneuili has been singled out from the genus Palaeanodonta Amalitzky based on differences in the structure of hinge margin established using the literature data. Both genera have been included in the family Palaeanodontidae, which used to be considered by the discoverer of this genus as a subjective synonym for the family Palaeomutelidae. The revision of W. Amalitskii’s collection has demonstrated that the original diagnosis of the genus con-tains a number of inaccuracies. This creates difficulties for identification of the genus Verneuilunio and complicates its placement within higher taxa. The paper presents a revised diagnosis of the genus Verneuilunio. The detailed description of its type species is provided. The genus Verneuilunio has been assigned to the family Naiaditidae based on the duplivincular and slightly amphidetic ligament. According to this feature, the genus under study is significantly different from other unio-like Late Permian non-marine bivalve genera (Palaeomutela, Palaeanodonta, Oligodontella, and Opokiella, often occurring in the same strata. The genus Verneuilunio mostly resembles some Late Carboniferous “atypical” unio-like species of the genus Anthraconaia Trueman et Weir. Statistical processing of the biometric parameters of Verneuilunio verneuili and the species A. pruvosti, mostly resembling it, has revealed statistically significant differences in elongation of the posterior end of the shell. To date, the geographic range of the genus Verneuilunio is restricted to the central part of the East European Platform, whereas its stratigraphic range is in the lower sublayer of the Severodvinsk layer.

  14. Location is everything: evaluating the effects of terrestrial and marine resource subsidies on an estuarine bivalve.

    Directory of Open Access Journals (Sweden)

    Joel M S Harding

    Full Text Available Estuaries are amongst the world's most productive ecosystems, lying at the intersection between terrestrial and marine environments. They receive substantial inputs from adjacent landscapes but the importance of resource subsidies is not well understood. Here, we test hypotheses for the effects of both terrestrial- and salmon-derived resource subsidies on the diet (inferred from stable isotopes of muscle tissue, size and percent nitrogen of the soft-shell clam (Mya arenaria, a sedentary estuarine consumer. We examine how these relationships shift across natural gradients among 14 estuaries that vary in upstream watershed size and salmon density on the central coast of British Columbia, Canada. We also test how assimilation and response to subsidies vary at smaller spatial scales within estuaries. The depletion and enrichment of stable isotope ratios in soft-shell clam muscle tissue correlated with increasing upstream watershed size and salmon density, respectively. The effects of terrestrial- and salmon-derived subsidies were also strongest at locations near stream outlets. When we controlled for age of individual clams, there were larger individuals with higher percent nitrogen content in estuaries below larger watersheds, though this effect was limited to the depositional zones below river mouths. Pink salmon exhibited a stronger effect on isotope ratios of clams than chum salmon, which could reflect increased habitat overlap as spawning pink salmon concentrate in lower stream reaches, closer to intertidal clam beds. However, there were smaller clams in estuaries that had higher upstream pink salmon densities, possibly due to differences in habitat requirements. Our study highlights the importance of upstream resource subsidies to this bivalve species, but that individual responses to subsidies can vary at smaller scales within estuaries.

  15. Location is everything: evaluating the effects of terrestrial and marine resource subsidies on an estuarine bivalve.

    Science.gov (United States)

    Harding, Joel M S; Segal, Michelle R; Reynolds, John D

    2015-01-01

    Estuaries are amongst the world's most productive ecosystems, lying at the intersection between terrestrial and marine environments. They receive substantial inputs from adjacent landscapes but the importance of resource subsidies is not well understood. Here, we test hypotheses for the effects of both terrestrial- and salmon-derived resource subsidies on the diet (inferred from stable isotopes of muscle tissue), size and percent nitrogen of the soft-shell clam (Mya arenaria), a sedentary estuarine consumer. We examine how these relationships shift across natural gradients among 14 estuaries that vary in upstream watershed size and salmon density on the central coast of British Columbia, Canada. We also test how assimilation and response to subsidies vary at smaller spatial scales within estuaries. The depletion and enrichment of stable isotope ratios in soft-shell clam muscle tissue correlated with increasing upstream watershed size and salmon density, respectively. The effects of terrestrial- and salmon-derived subsidies were also strongest at locations near stream outlets. When we controlled for age of individual clams, there were larger individuals with higher percent nitrogen content in estuaries below larger watersheds, though this effect was limited to the depositional zones below river mouths. Pink salmon exhibited a stronger effect on isotope ratios of clams than chum salmon, which could reflect increased habitat overlap as spawning pink salmon concentrate in lower stream reaches, closer to intertidal clam beds. However, there were smaller clams in estuaries that had higher upstream pink salmon densities, possibly due to differences in habitat requirements. Our study highlights the importance of upstream resource subsidies to this bivalve species, but that individual responses to subsidies can vary at smaller scales within estuaries.

  16. Effect of chronic selenium exposure on the freshwater bivalve Corbicula fluminea

    Energy Technology Data Exchange (ETDEWEB)

    Fournier, E.; Adam, C.; Massabuau, J.C.; Garnier-Laplace, J. [CEA Cadarache (DEI/SECRE/LRE), Laboratory of Radioecology and Ecotoxicology, Institute for Radioprotection and Nuclear Safety, 13 - Saint-Paul-lez-Durance (France)

    2004-07-01

    Selenium is essential for most of living organisms. In oxic to moderately oxic fresh-waters, Se exists predominantly in the (+VI) and (+IV) oxidation states as selenate (SeO{sub 4}{sup 2-}) and selenite (SeO{sub 3}{sup 2-}) respectively, whereas in the biota it is incorporated as Se(-II) into seleno-proteins or amino-acids, or as elemental selenium Se(0). At low concentrations, it acts against oxidative damages mainly as the glutathione peroxidase seleno-dependant, but it may be toxic at higher levels (for example, by replacing sulphur in important biomolecules). In filter feeders, such as the freshwater bivalve Corbicula fluminea, selected as biological model, the ventilation activity is a primary limiting step that controls the water influx and therefore the delivery of contaminants. Consequently, a series of short-term experiments were performed to study the effects of different dissolved Se concentrations and forms (selenite; selenate; selenomethionine) on the ventilation activity of Corbicula fluminea and Se tissular distribution. The modification of the ventilation activity of the Se-exposed groups, in comparison to this of reference groups (not exposed to Se) varied greatly according to the form and the concentrations of the Se used. Se concentrations in tissues indicated that selenite was the less bioavailable form whereas selenomethionine displayed the opposite trend. On the basis of this set of experiments, a limited number of conditions have been selected to provide highly contrasting ventilation flow rates and selenium bioaccumulation levels, in order to study the effects of long term exposures, i) at the molecular level, by measuring bio-markers of oxidative stress (forms of glutathione, glutathione peroxidase, glutathione reductase, superoxide dismutase, catalase, and bio-marker of genotoxicity (comet assay), ii) at the (sub)cellular level by analysing Se micro-localisation in target organs and iii) at the individual level by monitoring the variation

  17. Cadmium Accumulation and Metallothionein Response in the Freshwater Bivalve Corbicula fluminea Under Hydrodynamic Conditions.

    Science.gov (United States)

    Geng, Nan; Wang, Chao; Wang, Peifang; Qi, Ning; Ren, Lingxiao

    2015-06-01

    Freshwater bivalves such as Corbicula fluminea (Müller) are useful biomonitors for cadmium pollution because they absorb heavy metals and accumulate them in their tissues. We exposed C. fluminea in the laboratory to natural and cadmium (Cd)-spiked sediments below flowing water in order to evaluate the organisms' Cd accumulation and metallothionein (MT) response under hydrodynamic conditions. The accumulation of Cd and the induction of MT in C. fluminea were determined at 0, 1, 3, 6, 10, 16, and 23 days. Hydrodynamic conditions, represented by a water flow rate of 14 or 3.2 cm/s, increased Cd accumulation in the visceral mass, gill, foot, and mantle of C. fluminea in the first 3 or 6 days in the natural sediment. Cd concentrations in the C. fluminea tissues kept increasing over time in the three treatments, and significant differences were observed in Cd accumulation after 6 (visceral mass), 10 (foot) and 16 (gill and mantle) days among the three groups. The MT concentrations were barely affected by hydrodynamic conditions and were significantly linearly related to the Cd concentration in the visceral mass in the natural sediment and binomially related to it in the Cd-spiked sediment. Hydrodynamic conditions enhanced the accumulation of Cd in the soft tissues of C. fluminea, especially in the Cd-spiked sediment, but stronger hydrodynamic forces did not increase Cd accumulation. MT may be considered an indicator for Cd accumulation in C. fluminea under hydrodynamic conditions, but only when the Cd concentrations in the tissue remain below the toxic threshold values.

  18. Toxicokinetics of waterborne trivalent arsenic in the freshwater bivalve Corbicula fluminea.

    Science.gov (United States)

    Costa, Pedro M; Santos, Hugo M; Peres, Isabel; Costa, Maria H; Alves, Sheila; Capelo-Martinez, José Luís; Diniz, Mário S

    2009-08-01

    Arsenite (As(III)) uptake and elimination kinetics were studied in a freshwater bivalve, Corbicula fluminea, exposed to several nominal concentrations of As(III) (0, 100, 300, 500, and 1000 microg L(-1)) in a static 28-day assay, followed by a depuration stage of 14 days. At the end of each sampling time (days 0, 7, 28, and 42) whole-body portions were surveyed for total As concentrations and, complimentarily, surveyed for whole-body metallothionein (MT) induction to assess its role as a defense mechanism against exposure to As(III). Histochemical evaluation of the digestive gland was performed to verify As deposition and elimination in the tissue. Results show a significant increase in whole-body total As after 28 days of exposure for all treatments, followed by a decrease at the end of the depuration phase. Biodynamic kinetic models for As uptake and elimination were obtained from bioaccumulation data during the exposure phase, for all As treatments, by estimating uptake and elimination rate constants. Bioconcentration factors (BCFs) were estimated by the ratio of these constants. Results revealed that exposure to higher concentrations of As(III) causes a decrease in BCFs, suggesting that C. fluminea triggers effective regulatory mechanisms when exposed to higher concentrations of the metalloid. Significant induction of MT was detected during the exposure phase, followed by a decrease in MT concentration to control levels after depuration for all treatments. No significant differences in MT concentrations were observed between treatments. This finding may confirm the role of MT as part of the As regulation process, but its independence relative to concentrations of As(III) in water suggests that MT induction is not dose dependent. The histochemical evaluation provided clear evidence that As was effectively accumulated in the digestive gland during exposure and eliminated during depuration. The present work demonstrated that C. fluminea is capable of regulating As

  19. Eocene Antarctic seasonality inferred from high-resolution stable isotope profiles of fossil bivalves and driftwood

    Science.gov (United States)

    Judd, E. J.; Ivany, L. C.; Miklus, N. M.; Uveges, B. T.; Junium, C. K.

    2017-12-01

    The Eocene Epoch was a time of large-scale global climate change, experiencing both the warmest temperatures of the Cenozoic and the onset of southern hemisphere glaciation. The record of average global temperatures throughout this transition is reasonably well constrained, however considerably less is known about the accompanying changes in seasonality. Seasonally resolved temperature data provide a wealth of information not readily available from mean annual temperature data alone. These data are particularly important in the climatically sensitive high latitudes, as they can elucidate the means by which climate changes and the conditions necessary for the growth of ice sheets. Several recent studies, however, have suggested the potential for monsoonal precipitation regimes in the early-middle Eocene high latitudes, which complicates interpretation of seasonally resolved oxygen isotope records in shallow nearshore marine settings. Seasonal precipitation and runoff could create a brackish, isotopically depleted lens in these environments, depleting summertime δ18Ocarb and thereby inflating the inferred mean and range of isotope-derived temperatures. Here, we assess intra-annual variations in temperature in shallow nearshore Antarctic waters during the middle and late Eocene, inferred from high-resolution oxygen isotope profiles from accretionary bivalves of the La Meseta Formation, Seymour Island, Antarctica. To address concerns related to precipitation and runoff, we also subsample exceptionally preserved fossil driftwood from within the formation and use seasonal differences in δ13Corg values to estimate the ratio of summertime to wintertime precipitation. Late Eocene oxygen isotope profiles exhibit strongly attenuated seasonal amplitudes and more enriched mean annual values in comparison with data from the middle Eocene. Preliminary fossil wood data are not indicative of a strongly seasonal precipitation regime, implying that intra-annual variation in oxygen

  20. Haematopoiesis in molluscs: A review of haemocyte development and function in gastropods, cephalopods and bivalves.

    Science.gov (United States)

    Pila, E A; Sullivan, J T; Wu, X Z; Fang, J; Rudko, S P; Gordy, M A; Hanington, P C

    2016-05-01

    Haematopoiesis is a process that is responsible for generating sufficient numbers of blood cells in the circulation and in tissues. It is central to maintenance of homeostasis within an animal, and is critical for defense against infection. While haematopoiesis is common to all animals possessing a circulatory system, the specific mechanisms and ultimate products of haematopoietic events vary greatly. Our understanding of this process in non-vertebrate organisms is primarily derived from those species that serve as developmental and immunological models, with sparse investigations having been carried out in other organisms spanning the metazoa. As research into the regulation of immune and blood cell development advances, we have begun to gain insight into haematopoietic events in a wider array of animals, including the molluscs. What began in the early 1900's as observational studies on the morphological characteristics of circulating immune cells has now advanced to mechanistic investigations of the cytokines, growth factors, receptors, signalling pathways, and patterns of gene expression that regulate molluscan haemocyte development. Emerging is a picture of an incredible diversity of developmental processes and outcomes that parallels the biological diversity observed within the different classes of the phylum Mollusca. However, our understanding of haematopoiesis in molluscs stems primarily from the three most-studied classes, the Gastropoda, Cephalopoda and Bivalvia. While these represent perhaps the molluscs of greatest economic and medical importance, the fact that our information is limited to only 3 of the 9 extant classes in the phylum highlights the need for further investigation in this area. In this review, we summarize the existing literature that defines haematopoiesis and its products in gastropods, cephalopods and bivalves. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Polonium-210 in marine mussels (bivalve molluscs) inhabiting the southern coast of India

    International Nuclear Information System (INIS)

    Feroz Khan, M.; Godwin Wesley, S.; Rajan, M.P.

    2014-01-01

    The present study focused on the determination of the alpha-emitter, 210 Po, in two species of marine mussels (bivalve molluscs) commonly available in the southern coastal region of India. The brown mussel, Perna indica was collected from the west coast and the green mussel, Perna viridis from the east coast. The concentration of 210 Po was related to the allometry (length of shell, wet/dry weight of shell/soft tissue) of the mussels and significant results were found. The study period focused on three seasons namely, pre-monsoon, monsoon and post-monsoon for a 1-year period (2010–2011). The results revealed higher activity levels in smaller-sized mussels compared to larger ones. Marked variation in 210 Po activity concentration was noted in the whole-body soft tissues between seasons and sampling site (p < 0.05). The dose rate assessment for mussels was performed using the ERICA Assessment tool. The chronic exposure to mussels due to 210 Po was found to be lesser than the global benchmark dose rate of 10 μGy h −1 . The effective ingestion dose to adults who intake mussels was estimated to be in the range 5.1–34.9 μSv y −1 . The measurement contributes to the furthering of knowledge of 210 Po, since no data exist in this region. - Highlights: • Polonium-210 was quantified in two species of Mytilid mussels inhabiting southern coast of India. • Polonium-210 activity showed significant variation among size classes, between seasons and sampling site. • The internal dose rate to mussels and the dose assessment to the adult population were performed

  2. Regional-scale variation in size and abundance of the bivalve Varicorbula (Middle Miocene, Central Paratethys)

    Science.gov (United States)

    Fuksi, Tomáš; Tomašových, Adam; Rušin, Luboš

    2016-04-01

    Varicorbula gibba (Olivi, 1792) is a geologically long-ranging and ecologically generalistic bivalve species that appears in the Oligocene and persists to present, occurring in the tropical and northern temperate Eastern Atlantic and in the Mediterranean. Although it is one of the most frequent species in the benthic communities in the Paratethys during the Middle Miocene, spatial variation in its abundance, size, and shape is poorly known. Using bulk samples sieved with 1 mm mesh size, we investigate size and abundance variation of this taxon in molluscan communities in two basins in the Middle Miocene (Serravalian) sediments of the Central Paratethys. Bulk samples are derived from boreholes from the western (Vienna Basin) and eastern (Danube Basin) margins of the Malé Karpaty Mountains (Slovakia). We find that this taxon shows significant regional-scale differences in size distribution between the Vienna and Danube basins. In subtidal muds in the northern parts of the Vienna Basin, it achieves very high proportional community-level abundance and its median shell width ranges between 6-10 mm. In contrast, in muddy sands on the northeastern margin of the Danube Basin, community composition is more even and median width ranges just between 3-4 mm. The higher sandy content and lower sedimentation rates (as evidenced by higher taphonomic damage, with higher proportion of bored specimens, in the Danube Basin) imply that the size can partly positively correlate with nutrient supply. Morphometric analyses indicate that height and width of individuals of this taxon undergo significant allometry and that smaller-sized individuals in the Danube Basin have a smaller width/height ratio, suggesting that some shape differences between the two basins are unrelated to size differences.

  3. Habitat creation and biodiversity maintenance in mangrove forests: teredinid bivalves as ecosystem engineers

    Directory of Open Access Journals (Sweden)

    Ian W. Hendy

    2014-09-01

    Full Text Available Substantial amounts of dead wood in the intertidal zone of mature mangrove forests are tunnelled by teredinid bivalves. When the tunnels are exposed, animals are able to use tunnels as refuges. In this study, the effect of teredinid tunnelling upon mangrove forest faunal diversity was investigated. Mangrove forests exposed to long emersion times had fewer teredinid tunnels in wood and wood not containing teredinid tunnels had very few species and abundance of animals. However, with a greater cross-sectional percentage surface area of teredinid tunnels, the numbers of species and abundance of animals was significantly higher. Temperatures within teredinid-attacked wood were significantly cooler compared with air temperatures, and animal abundance was greater in wood with cooler temperatures. Animals inside the tunnels within the wood may avoid desiccation by escaping the higher temperatures. Animals co-existing in teredinid tunnelled wood ranged from animals found in terrestrial ecosystems including centipedes, crickets and spiders, and animals found in subtidal marine ecosystems such as fish, octopods and polychaetes. There was also evidence of breeding within teredinid-attacked wood, as many juvenile individuals were found, and they may also benefit from the cooler wood temperatures. Teredinid tunnelled wood is a key low-tide refuge for cryptic animals, which would otherwise be exposed to fishes and birds, and higher external temperatures. This study provides evidence that teredinids are ecosystem engineers and also provides an example of a mechanism whereby mangrove forests support intertidal biodiversity and nurseries through the wood-boring activity of teredinids.

  4. Biological Carbon Dioxide Assimilation Process Using Marine Phytoplankton Tetraselmis suecica and Bivalve Perna viridis

    Directory of Open Access Journals (Sweden)

    Sirichai Dharmvanij

    2012-01-01

    Full Text Available The Biological CO2 assimilation process using marine phytoplankton and marine bivalve was evaluated by carbon assimilation of the green mussel Perna viridis fed with Tetraselmis suecica under laboratory condition. Incorporation of carbon dioxide into phytoplankton biomass was performed through aeration. The experiment consisted of three treatments i.e. mussels without feeding (Control, mussels fed with T. suecica cultured with air (Treatment 1: T-Air, and mussels fed with T. suecica cultured with 1.5% CO2 in air (Treatment 2: T-CO2. The results showed that growth of mussels in T-Air and T-CO2 was 22.4 ± 4.0 mg/individual/day and 28.9 ± 12.3 mg/individual/day, respectively, which was significantly higher than control (mussels without feeding. Growth of mussels in T-Air was significantly lower than in T-CO2. Carbon content in shell (15.59 ± 0.57 % D.W. and meat (38.28 ± 1.72 % D.W. of mussels fed with aerated T. suecica (T-Air was significantly higher than that found in mussels fed with 1.5% CO2 T. suecica (14.2 ± 0.47 and 36.61± 0.43 % D.W. in shell and in meat, respectively (p≤0.05. With T-Air, 1.95±0.27 and 9.36±1.24% of carbon from T. suecica cells was assimilated into shell and meat of the mussel, respectively, while in T-CO2 , carbon assimilation from T. suecica cells in shell and meat was 2.19±0.55 and 11.22±2.76% respectively.

  5. Molluscs for Sale: Assessment of Freshwater Gastropods and Bivalves in the Ornamental Pet Trade

    Science.gov (United States)

    Tan, Siong Kiat; Wong, Wing Hing; Meier, Rudolf; Chan, Sow-Yan; Tan, Heok Hui; Yeo, Darren C. J.

    2016-01-01

    The ornamental pet trade is often considered a key culprit for conservation problems such as the introduction of invasive species (including infectious diseases) and overharvesting of rare species. Here, we present the first assessment of the biodiversity of freshwater molluscs in the ornamental pet trade in Singapore, one of the most important global hubs of the ornamental aquarium trade, and discuss associated conservation concerns. We recorded freshwater molluscs from ornamental pet shops and major exporters including non-ornamental species (e.g., hitchhikers, molluscs sold as fish feed). We recorded an unexpectedly high diversity—59 species—of freshwater bivalves and gastropods, with the majority (38 species or 64%) being from the Oriental region. In addition to morphological examination, we sequenced the DNA barcode region of mitochondrial CO1 and 16S genes to provide molecular data for the confirmation of the identification and for future re-identification. DNA barcodes were obtained for 50 species, and all but four were separated by > 3% uncorrected pairwise distances. The trade has been considered a main introduction pathway for non-native species to Singapore, and we found that out of 15 species in the trade as well as in the wild in Singapore, 12 are either introduced or of unknown origin, representing almost half of the known non-native freshwater molluscs in Singapore. Particularly prevalent are non-ornamental species: six hitchhikers on aquarium plants and six species sold as fish feed. We found that a quarter of the trade species have a history of introduction, which includes 11 known or potentially invasive species. We conclude that potential overharvesting is difficult to assess because only half of the trade species have been treated by IUCN. Of these, 21 species are of Least Concern and three are Data Deficient. Our checklist, with accompanying DNA barcodes, images, and museum vouchers, provides an important reference library for future

  6. Respiration of bivalves from three different deep-sea areas: Cold seeps, hydrothermal vents and organic carbon-rich sediments

    Science.gov (United States)

    Khripounoff, A.; Caprais, J. C.; Decker, C.; Le Bruchec, J.; Noel, P.; Husson, B.

    2017-08-01

    We studied bivalves (vesicomyids and mytilids) inhabiting four different areas of high sulfide and methane production: (1) in the Gulf of Guinea, two pockmarks (650 m and 3150 m depth) and one site rich in organic sediments in the deepest zone (4950 m average depth), (2) at the Azores Triple Junction on the Mid-Atlantic Ridge, one hydrothermal site (Lucky Strike vent field, 1700 m depth). Two types of Calmar benthic chambers were deployed, either directly set into the sediment (standard Calmar chamber) or fitted with a tank to isolate organisms from the sediment (modified Calmar chamber), to assess gas and solute exchanges in relation to bivalve bed metabolism. Fluxes of oxygen, total carbon dioxide, ammonium and methane were measured. At the site with organic-rich sediments, oxygen consumption by clams measured in situ with the standard benthic chamber was variable (1.3-6.7 mmol m-2 h-1) as was total carbon dioxide production (1-9.6 mmol m-2 h-1). The observed gas and solute fluxes were attributed primarily to bivalve respiration (vesicomyids or mytilids), but microbial and geochemical processes in the sediment may be also responsible for some of variations in the deepest stations. The respiration rate of isolated vesicomyids (16.1-0.25.7 μmol g-1 dry weight h-1) was always lower than that of mytilids (33 μmol g-1 dry weight h-1). This difference was attributed to the presence of a commensal scaleworm in the mytilids. The respiratory coefficient (QR) ≥1 indicated high levels of anaerobic metabolism. The O:N index ranged from 5 to 25, confirming that vesicomyids and mytilids, living in symbiosis with bacteria, have a protein-based food diet.

  7. Plio-Pleistocene extinctions and immigration credit reflected in the size-frequency distribution of Mediterranean marine bivalves

    Science.gov (United States)

    Nawrot, Rafal; Zuschin, Martin; Chattopadhyay, Devapriya

    2015-04-01

    Following the opening of the Suez Canal hundreds of Red Sea species have entered the Mediterranean Sea making it a global hot spot of marine bioinvasion. With the ongoing influx of the subtropical and tropical alien species and increasing sea surface temperatures, the Mediterranean biota is currently gaining a more tropical character and increasingly becoming a mixture of faunal stocks with different evolutionary histories. This susceptibility to invasion was suggested to reflect the presence of an empty ecological space left after decimation of incumbent warm-water fauna during Plio-Pleistocene climate fluctuations. As molluscs are among the most prolific immigrants, we test this hypothesis using data on taxonomic composition and body size of Pliocene Mediterranean bivalves derived from the literature sources and museum collections. The Pliocene inter-specific size-frequency distribution (SFD) is strikingly similar to the SFDs of the Recent Red Sea bivalve fauna, in spite of different biogeographic provenance and the absence of true reef ecosystems in the Pliocene of the Mediterranean region. In contrast, body-size patterns in both assemblages are significantly different from the present-day Mediterranean fauna characterized by smaller median and modal size. Our preliminary results suggest that the distinct shape of the modern Mediterranean SFD may reflect the selective nature of the late Piacenzian - Galesian (Late Pliocene - Early Pleistocene) extinctions pulses related to the onset of the Northern Hemisphere glaciations. These extinctions affected almost 40% of Pliocene species and were biased towards large-bodied taxa. They were not followed by re-immigration of warm-water species owing to the isolation from the tropical Atlantic biota by the cold upwelling along the NW coasts of Africa. The resulting invasion credit (sensu Jackson & Sax, 2010) is currently being paid by the Red Sea bivalves colonizing the Mediterranean Sea through the Suez Canal. Successful

  8. Urological manifestations of Duchenne muscular dystrophy.

    Science.gov (United States)

    Askeland, Eric J; Arlen, Angela M; Erickson, Bradley A; Mathews, Katherine D; Cooper, Christopher S

    2013-10-01

    Duchenne muscular dystrophy is a dystrophinopathy affecting males that is associated with multiple organ system complications. To our knowledge urological complications of Duchenne muscular dystrophy have been described only anecdotally to date. We reviewed the medical charts of 135 patients with Duchenne or Duchenne-Becker muscular dystrophy for demographics and disease progression, urological diagnoses, intervention and followup. Of 135 patients 67 (50%) had at least 1 documented urological diagnosis and 38 (28%) had multiple manifestations. Lower urinary tract symptoms were the most common urological diagnosis (32% of patients). Survival analysis revealed a median age at onset of lower urinary tract symptoms of 23 years (95% CI 17.7-23.9). Intervention was required in 12 patients (9%), most commonly due to nephrolithiasis. Urological morbidity increased with Duchenne muscular dystrophy progression when stratified by clinical progression. Lower urinary tract symptoms were more common in nonambulatory patients (40.7% vs 19%, p = 0.007), those with a diagnosis of scoliosis (44% vs 19.7%, p = 0.003) and/or scoliosis spine surgery (60% vs 22%, p <0.001), and those on invasive respiratory support (53% vs 29%, p = 0.046). Likewise, nephrolithiasis was more common in nonambulatory patients (10% vs 0%, p = 0.017), those with scoliosis (12% vs 0%, p = 0.004) and/or scoliosis spine surgery (20% vs 1%, p <0.001), and those on invasive respiratory support (29% vs 3%, p <0.001). Only 28% of patients with a urological manifestation were referred to urology. As these patients transition into adolescence and adulthood, the increased prevalence of urological manifestations warrants increased awareness and referral to urologists. Copyright © 2013 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  9. Skin Manifestations of Inflammatory Bowel Disease.

    Science.gov (United States)

    Greuter, Thomas; Navarini, Alexander; Vavricka, Stephan R

    2017-12-01

    Inflammatory bowel disease (IBD) with its two main subtypes Crohn's disease and ulcerative colitis is not restricted to the gastrointestinal tract. Indeed, so-called extraintestinal manifestations (EIMs) are frequent and considerably affect morbidity and mortality. The prevalence of EIMs ranges from 6 to 47%. In up to one quarter of the patients, EIMs can present even before an IBD diagnosis is established. The pathophysiology of EIMs remains elusive, although data from clinical trials demonstrating anti-tumor necrosis factor (TNF) efficacy suggest a common pathogenic link between intestinal and extraintestinal disease activity. However, not all EIMs parallel intestinal disease. Skin lesions are usually classified based on their pathophysiological association with the underlying intestinal disease into four categories: (1) specific, (2) reactive, (3) associated, and (4) treatment-induced manifestations. Cutaneous manifestations include erythema nodosum (EN), pyoderma gangrenosum (PG), Sweet's syndrome, and oral lesions, with EN being the most commonly reported and PG showing the most debilitating disease course. Anti-TNF-induced skin reactions are a new, but increasingly recognized phenomenon, which can be eventually misinterpreted as psoriatic lesions. Medical treatment modalities are limited with topical and systemic steroids being the most frequently employed agents. If EIMs parallel intestinal disease activity, the therapeutic cornerstone usually is the management of underlying intestinal disease activity rather than direct treatment of the EIMs. However, increasing evidence for anti-TNF agents' efficacy in EIM management has changed the approach to complicating and debilitating disease courses. In the case of anti-TNF-induced lesions, topical steroids are usually sufficient and discontinuation of anti-TNF is seldom warranted. In this review, we summarize current knowledge on cutaneous EIMs, their diagnostic criteria and clinical presentation, natural history

  10. The Manifestation of Corruption in Eastern Europe

    Directory of Open Access Journals (Sweden)

    Viacheslav Hladky

    2018-01-01

    Full Text Available The purpose of this article is to identify the main manifestations of corruption in the states of Eastern Europe, and, first of all, in Ukraine, which since 2014 has been actively carrying out multiple anti-corruption transformations, although the state is becoming increasingly corrupt every year. The author defines the main groups of manifestations of corruption and analyzes their constituent elements, in the light of which, delineates such categories as "gratitude", bribe, and corruption "gratitude". Particular attention is paid to the study of corruption intercession, which unites nepotism, cronyism and corruption lobbying. It is noted that to date nepotism is essentially supplanted by the rabble, which is the advantage of "privatization" of the state in the light of the clan capitalism. It is concluded that bribery and deviant intercession (corruption protection, as the main manifestations of corruption, the facts that corruption behavior is life-affirming security and protective actions of people, to which they resort, on the one hand, because of the insolvency of the state and society, but, on the other hand, to optimize the achievement of the good that is provided by the state and society, however, in an improper way. Meanwhile, if the discrepancy measures and methods of granting the benefits of state benefits (i.e., on average, the measure and method is applicable, then ignoring the state provision of certain goods as such (i.e., they can be provided only in the corruption plane - this phenomenon is completely objective. On this basis, it is argued that the policy of counteracting corrupt practices in the state should focus, first of all, on the solution of such problems and objective problems, the refusal to account, which will lead to further criminalization of the society, which is observed, in particular, in modern Ukraine.

  11. Abundance, biomass and caloric content of Chukchi Sea bivalves and association with Pacific walrus (Odobenus rosmarus divergens) relative density and distribution in the northeastern Chukchi Sea

    Science.gov (United States)

    Young, Jordann K.; Black, Bryan A.; Clarke, Janet T.; Schonberg, Susan V.; Dunton, Kenneth H.

    2017-10-01

    The northeastern Chukchi Sea is a shallow subarctic shelf ecosystem that supports a substantial benthic infaunal community of which bivalves are a major component. We assessed the patterns in population abundance, biomass, and caloric content of ten dominant bivalve taxa in relation to the distribution of the upper trophic level consumer Pacific walrus (Odobenus rosmarus divergens). Bivalves were collected over four cruises in the northeastern Chukchi Sea (2009, 2010, 2012, 2013). Our samples were largely dominated by calorie-dense, deposit-feeding species, including Macoma spp., Ennucula tenuis, Nuculana spp. and Yoldia spp. Weight-frequency distributions were strongly right-skewed for most taxa, though some showed evidence of a bimodal distribution. Caloric densities as measured through bomb calorimetry significantly differed among taxa (ANOVA F = 32.57, df = 9, p-valueanimal wet weight was found to be a reliable predictor of whole animal caloric content. Bivalve populations and peak caloric densities were centered on and to the southeast of Hanna Shoal, which coincided with peak Pacific walrus relative density (walruses per km surveyed) from July through October. Significant differences in mean caloric values were found between areas with and without walruses present (student's t-test, t=-2.9088, df = 252.24, p-value = 0.003952), as well as between areas with low and high walrus relative densities in the pooled annual dataset and in each individual month except October (ANOVA, p-value<0.05). The high-calorie deposit feeders that dominate these bivalve communities preferentially consume food sources, such as sea ice algae, that are likely to be affected by shifting sea ice dynamics. As such, continued warming has the potential to alter bivalve communities in the northeastern Chukchi Sea, which may have profound implications for upper trophic levels.

  12. Oral Manifestations and Complications of Diabetes Mellitus

    Science.gov (United States)

    Al-Maskari, Awatif Y.; Al-Maskari, Masoud Y.; Al-Sudairy, Salem

    2011-01-01

    Diabetes mellitus is a chronic disease affecting all age groups. It is one of the leading causes of mortality and morbidity worldwide. Many chronic macrovascular and microvascular complications of diabetes have been reported in the literature with few reports about oral complications. This article aims to review and increase the awareness of oral manifestations and complications of diabetes mellitus and to stimulate research on the subject. It treats in depth some of the complications such as periodontal disease, fungal infection and salivary dysfunction while other complications are mentioned briefly. PMID:21969888

  13. Norwegian scabies - rare case of atypical manifestation.

    Science.gov (United States)

    Ebrahim, Karina Corrêa; Alves, Júlia Barazetti; Tomé, Lísias de Araújo; Moraes, Carlos Floriano de; Gaspar, Arianne Ditzel; Franck, Karin Fernanda; Hussein, Mohamad Ali; Cruz, Lucas Raiser da; Ebrahim, Leonardo Duque; Sidney, Luis Felipe de Oliveira

    2016-01-01

    Human scabies affects all social classes and different races around the world. It is highly contagious, but the exact figures on its prevalence are unknown. A 19-year-old male patient was admitted to the emergency room reporting fever (38°C) and multiple lesions throughout the body, except face, soles, and palms. Lesions were non-pruritic, which hampered the initial diagnostic suspicion. Skin biopsy was performed, and the final diagnosis was crusted scabies (Norwegian). It was concluded that human scabies is a significant epidemic disease, due to its different clinical manifestations, and because it is extremely contagious.

  14. Oral manifestation of histoplasmosis on the palate*

    Science.gov (United States)

    de Souza, Barbara Capitanio; Munerato, Maria Cristina

    2017-01-01

    This case report describes an uncommon manifestation of histoplasmosis on the soft palate. The importance of appropriate treatment and follow-up in complex cases is emphasized, especially in patients with chronic diseases. Oral lesions may occur as multiple, granular and painful ulcers, as well as verrucous growths. Lesions may also be deep, with infiltrative edges and erythematous or with white areas, accompanied by local lymphadenopathy, resembling a carcinoma on clinical examination. In this sense, a fast and accurate diagnosis is essential to the success of treatment of oral histoplasmosis. PMID:29267463

  15. Oral manifestation of histoplasmosis on the palate.

    Science.gov (United States)

    Souza, Barbara Capitanio de; Munerato, Maria Cristina

    2017-01-01

    This case report describes an uncommon manifestation of histoplasmosis on the soft palate. The importance of appropriate treatment and follow-up in complex cases is emphasized, especially in patients with chronic diseases. Oral lesions may occur as multiple, granular and painful ulcers, as well as verrucous growths. Lesions may also be deep, with infiltrative edges and erythematous or with white areas, accompanied by local lymphadenopathy, resembling a carcinoma on clinical examination. In this sense, a fast and accurate diagnosis is essential to the success of treatment of oral histoplasmosis.

  16. Pulmonary manifestations of systemic lupus erythematosus

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Kee Hyuk; Choi, Yo Won; Jeon, Seok Chol; Park, Choong Ki; Joo, Kyung Bin; Hahm, Chang Kok; Lee, Seung Ro [College of Medicine, Hanyang Univ., Seoul (Korea, Republic of)

    2004-02-01

    Pulmonary involvement is more common in systemic lupus erythematosus (SLE) than in any other connective tissue disease, and more than half of patients with SLE suffer from respiratory dysfunction during the course of their illness. Although sepsis and renal disease are the most common causes of death in SLE, lung disease is the predominant manifestation and is an indicator of overall prognosis. Respiratory disease may be due to direct involvement of the lung or as a secondary consequence of the effect of the disease on other organ systems.

  17. Osteo-articular manifestations of amyloidosis.

    Science.gov (United States)

    M'bappé, Pauline; Grateau, Gilles

    2012-08-01

    Whether it is overload disease or mispleated proteins, amyloid is a great pretender. This is especially true for all of the osteo-articular manifestations of amyloid light chain (AL) amyloidosis, which may mimic rheumatoid arthritis, polymyalgia rheumatica, a myeloma or a bone tumour. To improve the prognosis, AL amyloidosis must be considered in front of atypical osteo-articular manifestations. Amyloidosis Ab2M of chronic haemodialysis (members' arthropathy and destructive spondylitis) is a specific entity that needs to be differentiated from other osteoarthropathies of chronic renal failure. It has become exceptional since the progress of haemodialysis. Finally transthyretin amyloidosis(ATTR) can be responsible for carpal tunnel syndrome(CTS) in its genetic and senile form. Although amyloidosis is rare, it represents one of the aetiologies of CSC, regardless of its type. In the specific context of haemodialysis, this poses no difficulty for the clinician. Yet AL amyloidosis must be considered more often, as must senile amyloidosis ATTR in the elderly. It seems obvious that the anatomo-pathologic analysis with specific staining with Congo red - see typing - should be systematically performed in the case of surgical neurolysis. Amyloidosis is defined by the extracellular deposit of proteins which share common tinctorial affinities, a fibril aspect under electron microscopy and spatial conformation called beta pleated. Once regarded as a mere overload disease, it is currently considered as a disease of misfolded proteins. Indeed, it is certain that abnormalities of spatial pattern play an essential role in the responsibility for the pathology of many proteins whose amyloid fibre is the final common way. They involve both changes in the conformation of proteins and other major in vivo interactions between amyloid protein and the extracellular matrix. In most cases, amyloidosis represents the bulk of histopathological lesions and its pathogenic role is certain. In

  18. Various musculoskeletal manifestations of chronic renal insufficiency

    International Nuclear Information System (INIS)

    Lim, C.Y.; Ong, K.O.

    2013-01-01

    Musculoskeletal manifestations in chronic renal insufficiency are caused by complex bone metabolism alterations, now described under the umbrella term of chronic kidney disease mineral- and bone-related disorder (CKD-MBD), as well as iatrogenic processes related to renal replacement treatment. Radiological imaging remains the mainstay of disease assessment. This review aims to illustrate the radiological features of CKD-MBD, such as secondary hyperparathyroidism, osteomalacia, adynamic bone disease, soft-tissue calcifications; as well as features associated with renal replacement therapy, such as aluminium toxicity, secondary amyloidosis, destructive spondyloarthropathy, haemodialysis-related erosive arthropathy, tendon rupture, osteonecrosis, and infection

  19. The quagga mussel (Dreissena rostriformis bugensis Andrusov, 1897) – another Ponto-Caspian dreissenid bivalve in the southern Baltic catchment: the first record from the Szczecin Lagoon

    OpenAIRE

    Adam Woźniczka; Brygida Wawrzyniak-Wydrowska; Teresa Radziejewska; Anna Skrzypacz

    2016-01-01

    In 2014, a non-indigenous dreissenid bivalve, the quagga mussel (Dreissena rostriformis bugensis Andrusov, 1897) was for the first time recorded in the Szczecin Lagoon. This was also the first record of the species in the Baltic Sea catchment. The quagga mussel was found to accompany the zebra mussel (Dreissena polymorpha), a non-indigenous bivalve already firmly established in the Lagoon. As indicated by the new immigrant's estimated abundance (4000.0 ± 355.44 ind. m−2) and the zebra mussel ...

  20. Field clearance of an intertidal bivalve bed: relative significance of the co-occurring blue mussel Mytilus edulis and Pacific oyster Crassostrea gigas

    DEFF Research Database (Denmark)

    Vismann, Bent; Holm, Mark Wejlemann; Davids, Jens

    2016-01-01

    At an approximately 12 000 m2 sheltered intertidal bivalve bed in the western part of the Limfjord, Denmark, the Pacific oyster Crassostrea gigas co-occurs with the blue mussel Mytilus edulis. The relative significance of the impact of the 2 species on phytoplankton density during a tidal cycle...... was estimated by combining field measurements of clearance rates and modelling of the bivalve bed (topography, biomass distribution, temporal and spatial water coverage and depth). The average density of C. gigas and M. edulis was 35 ± 36 and 1001 ± 685 ind. m−2, respectively. The water volume cleared during...

  1. Hematologic manifestations of Helicobacter pylori infection

    Science.gov (United States)

    Campuzano-Maya, Germán

    2014-01-01

    Helicobacter pylori (H. pylori) is the most common infection in humans, with a marked disparity between developed and developing countries. Although H. pylori infections are asymptomatic in most infected individuals, they are intimately related to malignant gastric conditions such as gastric cancer and gastric mucosa-associated lymphoid tissue (MALT) lymphoma and to benign diseases such as gastritis and duodenal and gastric peptic ulcers. Since it was learned that bacteria could colonize the gastric mucosa, there have been reports in the medical literature of over 50 extragastric manifestations involving a variety medical areas of specialization. These areas include cardiology, dermatology, endocrinology, gynecology and obstetrics, hematology, pneumology, odontology, ophthalmology, otorhinolaryngology and pediatrics, and they encompass conditions with a range of clear evidence between the H. pylori infection and development of the disease. This literature review covers extragastric manifestations of H. pylori infection in the hematology field. It focuses on conditions that are included in international consensus and management guides for H. pylori infection, specifically iron deficiency, vitamin B12 (cobalamin) deficiency, immune thrombocytopenia, and MALT lymphoma. In addition, there is discussion of other conditions that are not included in international consensus and management guides on H. pylori, including auto-immune neutropenia, antiphospholipid syndrome, plasma cell dyscrasias, and other hematologic diseases. PMID:25278680

  2. Canine MPV17 truncation without clinical manifestations

    Directory of Open Access Journals (Sweden)

    Reetta L. Hänninen

    2015-10-01

    Full Text Available Mitochondrial DNA depletion syndromes (MDS are often serious autosomal recessively inherited disorders characterized by tissue-specific mtDNA copy number reduction. Many genes, including MPV17, are associated with the hepatocerebral form of MDS. MPV17 encodes for a mitochondrial inner membrane protein with a poorly characterized function. Several MPV17 mutations have been reported in association with a heterogeneous group of early-onset manifestations, including liver disease and neurological problems. Mpv17-deficient mice present renal and hearing defects. We describe here a MPV17 truncation mutation in dogs. We found a 1-bp insertion in exon 4 of the MPV17 gene, resulting in a frameshift and early truncation of the encoded protein. The mutation halves MPV17 expression in the lymphocytes of the homozygous dogs and the truncated protein is not translated in transfected cells. The insertion mutation is recurrent and exists in many unrelated breeds, although is highly enriched in the Boxer breed. Unexpectedly, despite the truncation of MPV17, we could not find any common phenotypes in the genetically affected dogs. The lack of observable phenotype could be due to a late onset, mild symptoms or potential tissue-specific compensatory mechanisms. This study suggests species-specific differences in the manifestation of the MPV17 defects and establishes a novel large animal model to further study MPV17 function and role in mitochondrial biology.

  3. Non-cardiac manifestations of Marfan syndrome

    Science.gov (United States)

    2017-01-01

    Because of the widespread distribution of fibrillin 1 in the body, Marfan syndrome (MFS) affects virtually every system. The expression of this single dominantly inherited gene is variable within a family, and between families. There is some genotype-phenotype correlation which is helpful in guiding long-term prognosis, and management. In general gene mutations have been reported in clusters, with those having mainly ocular manifestations occurring in exons 1 to 15 of this 65-exon gene; those causing cardiac problems often involving cysteine replacement in a calcium binding EGF-like sequence; the most severe mutations occurring in exons 25–32, causing neonatal MFS diagnosed at birth, and severe enough to cause death frequently before the age of 2. Other correlations will certainly be found in future. This condition is progressive, and the manifestations unfold according to age. For example, if the lens is going to dislocate this usually occurs by age 10; scoliosis usually presents itself between the ages of 8 and 15; height should be monitored carefully between the onset of puberty and cessation of growth approximately age 17 or 18. Holistic care should be offered by one doctor who oversees the patient’s welfare. This should be a paediatrician, paediatric cardiologist, or general practitioner in the case of an affected child. Thereafter, the physician in charge of the most seriously affected system should be aware that other systems need to be managed through a referral network. PMID:29270372

  4. Pharyngolaryngeal manifestations of post-polio syndrome

    Directory of Open Access Journals (Sweden)

    Biase, Noemi Grigoletto De

    2011-10-01

    Full Text Available Introduction: The post-polio syndrome (PPS is characterized by a new episod of atrophy or muscle weakness in individuals previously affected by poliomyelitis. The symptoms start from an extended period of clinical stability ranging from 20 to 40 years, after the initial chart of polio. Among the pathophysiological mechanisms, the most likely is that the syndrome represents a process of attrition and neuronal metabolic exhaustion due to a continuous process of denervation reinnervation which begins after the initial acute. Objective: Review the clinical characteristics and pathophysiological of PPS,as well as present the approach in cases with pharyngolaryngeal manifestations. Case Report: We present the clinical case of a male patient with 48 years old, with main complaints of dysphonia, dysphagia and previous history of polio. The patient underwent a diagnostic investigation, in which the voice psychoacoustic findings are described. Laringoscopic, electromyographic and the videoendoscopy of swallowing compatible with PPS. The treatment consisted in phonotherapy in a total of 11 weekly sessions and guidelines for swallowing, with satisfactory improvement of the symptoms. Final comments: The pharyngolaryngeal manifestations of PPS are susceptible to treatment, obtaining satisfactory results, with improvement of life quality of the patients.

  5. CT manifestation of cervical tuberculous lymphadenitis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Joo; Sung, Ki Jun; Kang, Myung Jae; Kim, Myung Soon [Yonsei University Wonju Medical College, Wonju (Korea, Republic of)

    1992-03-15

    Cervical tuberculous lymphadenitis is a commonly encountered disease, especially in adults. Differentiation from other lymphadenopathy and benign conditions such as cystic neck masses is important. CT findings of tuberculous lymphadenopathy in the abdomen and thorax are reported in many literatures. But there are only a few articles concerning cervical tuberculous lymphadenopathy. The authors retrospectively analyzed CT findings of 33 cases with cervical tuberculous lymphadenitis regarding distribution, contour, enhancing pattern, change of adjacent facial plane, and dermal and subcutaneous manifestations. We concluded that the presence of conglomerated nodal masses with central lucency, thick irregular rim of contrast enhancement and nodularity, varying degree of homogenous enhancement in smaller nodes,dermal and subcutaneous manifestations of inflammation such as thickening of overlying skin, engorgement of the lymphatics and thickening of adjacent muscles, and diffusely effaced fascial plane are suggestive of tuberculous lymphadenitis. However, some CT patterns of tuberculous adenitis may be seen in order diseases: for example, enhancement can occur in hyperplastic nodes, vascular metastasis (thyroid, melanoma, and hypernephroma), lymphoma, granulomatous disease, and Castleman's disease.

  6. CT manifestation of cervical tuberculous lymphadenitis

    International Nuclear Information System (INIS)

    Kim, Young Joo; Sung, Ki Jun; Kang, Myung Jae; Kim, Myung Soon

    1992-01-01

    Cervical tuberculous lymphadenitis is a commonly encountered disease, especially in adults. Differentiation from other lymphadenopathy and benign conditions such as cystic neck masses is important. CT findings of tuberculous lymphadenopathy in the abdomen and thorax are reported in many literatures. But there are only a few articles concerning cervical tuberculous lymphadenopathy. The authors retrospectively analyzed CT findings of 33 cases with cervical tuberculous lymphadenitis regarding distribution, contour, enhancing pattern, change of adjacent facial plane, and dermal and subcutaneous manifestations. We concluded that the presence of conglomerated nodal masses with central lucency, thick irregular rim of contrast enhancement and nodularity, varying degree of homogenous enhancement in smaller nodes,dermal and subcutaneous manifestations of inflammation such as thickening of overlying skin, engorgement of the lymphatics and thickening of adjacent muscles, and diffusely effaced fascial plane are suggestive of tuberculous lymphadenitis. However, some CT patterns of tuberculous adenitis may be seen in order diseases: for example, enhancement can occur in hyperplastic nodes, vascular metastasis (thyroid, melanoma, and hypernephroma), lymphoma, granulomatous disease, and Castleman's disease

  7. Neurological manifestations of Batch s disease

    International Nuclear Information System (INIS)

    Borhani-Haghighi, Afshin; Ashjazadeh, Nahid; Nikseresht, Alireza; Shariat, Abdolhamid; Yousefipour, Gholamali; Samangooie, Shahdokht; Safari, Anahid

    2006-01-01

    To determine the prevalence, clinical manifestations, and laboratory features of Neuro-Behcets disease. This prospective study was carried out in the Behcets Research Clinic in Shiraz (south-west Iran) and included the patients referred from 1990-1999. The patients' clinical records, images, CSF analyses, and electrodiagnostic studies were reviewed. Eighteen (15 males and 3 females) out of 690 Behcet s patients (2.6%, 95% CI = 1.4-3.8%) were found to have neurological involvement. The mean +/- standard deviation age of these patients was 34.7 +/- 8.6 years. All fulfilled the criteria of the International Study Group of Behcet s Disease. Central nervous system involvement was more common than peripheral nervous system manifestations. Headache, weakness, tingling, and numbness were the most common symptoms. Hyperreflexia, upward plantar reflex, and somatosensory findings were the most frequent signs. Hemispheral and brainstem stroke-like syndromes and cerebral venous thrombosis were the major neurologic presentations. There were also cases of myelitic, pure meningoencephalitic, amyotrophic lateral sclerosis-like, multiple sclerosis-like, and Guillain Barre syndromes. Neuro-Behcets disease must be considered in the differential diagnosis of stroke in young adults, chronic meningitis, intracranial hypertension, multiple sclerosis, myelopathies, and peripheral neuropathies. (author)

  8. 76 FR 36363 - Hazardous Waste Manifest Printing Specifications Correction Rule

    Science.gov (United States)

    2011-06-22

    ... change will afford authorized manifest form printers greater flexibility in complying with the Federal... apply to me? Entities potentially affected by this action are the hazardous waste manifest printers... March 2005 rule also established the Manifest Registry system to ensure that authorized printers: (1...

  9. The vesicomyid bivalve habitat at cold seeps supports heterogeneous and dynamic macrofaunal assemblages

    Science.gov (United States)

    Guillon, Erwan; Menot, Lénaïck; Decker, Carole; Krylova, Elena; Olu, Karine

    2017-02-01

    The high biodiversity found at cold seeps, despite elevated concentrations of methane and hydrogen sulfide, is attributed to multiple sources of habitat heterogeneity. In addition to geological and geochemical processes, biogenic habitats formed by large symbiont-bearing taxa, such as bivalves and siboglinid tubeworms, or by microbial mats drive the biodiversity of small-sized fauna. However, because these habitat-forming species also depend on geochemical gradients, the respective influence of abiotic and biotic factors in structuring associated macrofaunal communities is often unresolved. The giant pockmark Regab located at 3200 m depth on the Congo margin is characterized by different fluid-flow regimes, providing a mosaic of the most common biogenic habitats encountered at seeps: microbial mats, mussel beds, and vesicomyid clam beds; the latter being distributed along a gradient of environmental conditions from the center to the periphery of the pockmark. Here, we examined the structure of macrofaunal communities in biogenic habitats formed in soft sediment to (1) determine the influence of the habitats on the associated macrofaunal communities (inter-habitat comparison), (2) describe how macrofaunal communities vary among vesicomyid clam beds (intra-habitat comparison) and (3) assess the inter-annual variation in vesicomyid beds based on repeated sampling at a three-year interval. The highest densities were found in the microbial mat communities in intermediate fluid-flow areas, but they had low diversity - also observed in the sediment close to mussel beds. In contrast, vesicomyid beds harbored the highest diversity. The vesicomyid beds did not show a homogeneous macrofaunal community across sampled areas; instead, density and composition of macrofauna varied according to the location of the beds inside the pockmark. The clam bed sampled in the most active, central part of the pockmark resembled bacterial mat communities by the presence of highly sulfide

  10. Effect of the exposure to suspended solids on the enzymatic activity in the bivalve Sinonovacula constricta

    Directory of Open Access Journals (Sweden)

    Guojun Yang

    2017-01-01

    Full Text Available Aquatic animals are susceptible to sudden changes of their living environment but they adopt strategies to cope with adverse environmental challenges. Contamination by suspended solids, often associated with a dramatic change in the concentrations of important water-quality variables is a frequent occurrence in China's coastal waters and estuaries. Here we studied the impact of suspended solids on the activities of the antioxidant enzymes superoxide dismutase (SOD and catalase (CAT, as well as adenosine triphosphates (including Na+ K+-ATPase, Mg+ +-ATPase, Ca+ +-ATPase and H+ K+-ATPase in the gills and visceral mass tissues of the molluscan bivalve Sinonovacula constricta exposed (4, 8, 12, 16, 20, and 24 days to various concentrations of suspended solids. Our results showed that the antioxidant enzymes cooperated closely to effectively scavenge superoxide anion free radicals and H2O2 (which can ultimately inhibit gill activity through the modification of SOD and/or CAT enzymatic activities. ATPases activity (considered to be a sensitive indicator of toxicity could play an effective role in the maintenance of functional integrity of the plasma membranes as well as some other intracellular functions. After the exposure, a decrease in the Na+ K+-ATPase, Mg+ +-ATPase, and Ca+ +-ATPase activity of the gills was observed suggesting that they were inhibited by the treatments. These results also indicated that, from day 4 to day 16, exposure to high concentrations of suspended solids had an inhibitory effect on the activity of H+-K+-ATPase in the visceral mass of S. constricta. However, after a period of adaptation the H+-K+-ATPase activity was restored to original levels. Our results suggest that long-term exposure to high levels of suspended solids disturb osmoregulation, gastric acid secretion and digestion, cause oxidative damage, as a consequence of antioxidant enzymes inactivation which eventually damages the gills, affect the food intake

  11. Distribution and density of the bivalve Anomalocardia brasiliana in the estuarine region of Northeastern Brazil

    Directory of Open Access Journals (Sweden)

    A. M. L. Rodrigues Maia

    2017-06-01

    Full Text Available Abstract The objective of this study was to analyze the density and distribution of the bivalve Anomalocardia brasiliana in beaches in the estuarine region of the semiarid in Rio Grande do Norte State, Barra and Pernambuquinho (04°56.978’S and 37°08.961’W and 04°56.792’S and 37°09.375’W, respectively. Samples were collected monthly during 37 months using five transects (300 m long and 400 m apart laid perpendicularly to the beach line toward the sea. Seven collection points, 50 m apart, were set in each transect, and shellfish and sediment samples were collected. Temperature and salinity were measured in each transect. The results showed a temperature variation of average values of 3 °C; the greatest variation (33.2 °C was observed in May of 2009. The lowest average salinity values were observed between April and June of 2009 (5, 8.7, and 7.8, respectively. This fact was due to an atypical rainfall in the region, which resulted in a large freshwater inflow into the estuary; the average salinity values were about 40 in the remaining months. The highest precipitation values were observed in April/09, April/10, and April/11; the highest precipitation occurred in April/09 (316.3 mm. The lower average densities of A. brasiliana were observed in April and May/09 when compared to the other months; the lowest value was observed in April/09 (26 ind/m2. The highest densities occurred between November/10 and July/11, with values ranging from 70 to 322 ind/m2. The highest inflow of young individuals (lengths from 2 to 5 mm was observed between April and June of 2010 and on September/10 while the highest frequency of adults (from 20 to 25 mm occurred between December of 2010 and April of 2011. Hence, the results of this study show that in the months with the greatest rainfall, salinity and the average density of A. brasiliana showed the lowest values.

  12. Mechanisms of cadmium accumulation (adsorption and absorption) by the freshwater bivalve Corbicula fluminea under hydrodynamic conditions.

    Science.gov (United States)

    Nan, Geng; Peifang, Wang; Chao, Wang; Jun, Hou; Jin, Qian; Lingzhan, Miao

    2016-05-01

    Many heavy metals in sediments and water have potential adverse effects on aquatic organisms such as Corbicula fluminea (O.F. Müller, 1774), a bivalve species frequently used as a biomonitor for metal pollution. Studies over the past decades examining the heavy metal uptake by C. fluminea, very few has investigated the effect of hydrodynamic conditions on accumulation of heavy metal by C. fluminea. Therefore, in this study, to investigate the mechanism of intracellular and extracellular accumulation of metal, individuals of C. fluminea were exposed to cadmium (Cd)-treated water under three different hydrodynamic conditions. These included exposures in two set ups: three rates of rotation (500, 350, 200 r/min) in beakers for 10 days, and then exposure to Cd-treated sediment under two naturally turbulent water conditions (14 cm/s and 3.2 cm/s) in experimental flumes for 23 days. Hydrodynamic force increased the burrowing rate but decreased the activity of C. fluminea. After 10 days of exposure, the extracellular concentrations of Cd in the tissues of C. fluminea in the sand group were significantly higher than that in the gravel groups. The intracellular and extracellular concentrations of Cd in the tissues of C. fluminea dramatically increased in the Cd-treated sediment test. Moreover, the concentration of the extracellular Cd adsorbed on the tissues of C. fluminea in the 14 cm/s and 3.2 cm/s groups was significantly higher than that in the control group, whereas the effect of hydrodynamic force on absorption of Cd by C. fluminea was not obvious. These results suggest that hydrodynamic condition plays an important role in extracellular accumulation of Cd by C. fluminea. In future study, when using C. fluminea to assess Cd pollution in aquatic environment, extracellular Cd adsorbed on the tissue should be removed to avoid the influence of hydrodynamics. Copyright © 2016. Published by Elsevier Ltd.

  13. Analyzing shell size variability in the opportunistic bivalve Corbula gibba: comparing Recent and fossil data

    Science.gov (United States)

    Tomášových, Adam; Fuksi, Tomáš; Zuschin, Martin

    2017-04-01

    Corbula gibba is a first-order opportunistic bivalve species presently inhabiting the Eastern Atlantic and Mediterranean. This species is abundant in fossil benthic assemblages in Middle Miocene sediments of the Central Paratethys (Vienna and Danube Basins). Its indicator value for interpretation of past environmental conditions remains poorly explored and requires studies combining paleoecological, taphonomic, sclerochronological, and allometric approaches. First, meta-analysis of published abundance and body size patterns in living assemblages collected in the Adriatic Sea revealed that in spite of the westward increase in primary productivity in the northern Adriatic Sea, size structure of living assemblages of C. gibba during the 20th century does not differ between the northeastern (mesotrophic) and northwestern (eutrophic) coasts Adriatic Sea, with size-frequency distributions showing minimal differences in maximum shell size. Second, samples from cores from the northern Adriatic that span the past centuries to few millennia show that past populations of C. gibba inhabiting northeastern Adriatic had significantly smaller sizes than today, suggesting that the lack of size differences in the 20th century is a relatively young phenonemon triggered by recent eutrophication events. However, population densities are still significantly higher on the western side of the Adriatic Sea and in the Gulf of Trieste. Third, a broad-scale macroecological comparison of size-frequency distributions of molluscan assemblages with dominant C. gibba from the eastern Mediterranean (Israel) shows significantly smaller shells, relative to larger shells from the Adriatic Sea. This increase in shell size correlates positively with an increase in chlorophyll concentrations. We observed a size gradient of similar magnitude in Middle Miocene assemblages with C. gibba between the Vienna and Danube basins. Fossil C. gibba shells size from the northeastern margin of the Danube Basin

  14. Gal/GalNAc specific multiple lectins in marine bivalve Anadara granosa.

    Science.gov (United States)

    Adhya, Mausumi; Singha, Biswajit

    2016-03-01

    Complete lectin mapping of molluscs with their diversified recognition pattern and possible role in lectin-carbohydrate interaction based immune response triggering need much attention. In this communication, Gal/GalNAc specific three lectins AGL-IA (Anadara granosa lectin-IA), AGL-IB (A. granosa lectin-IB) and AGL-IV (A. granosa lectin-IV) and a lectin having hemolytic activity AGL-III (A. granosa lectin-III) were purified from the plasma of A. granosa bivalve by a combination of gel filtration and affinity chromatography. AGL-IA and IB were oligomeric lectins whereas, AGL-III and IV were monomeric. The molecular weight of AGL-IA, IB, III and IV were 375, 260, 45 and 33 kDa respectively. AGL-IA and IV agglutinated both rabbit and pronase treated human erythrocytes, whereas AGL-IB agglutinated only rabbit erythrocytes. AGL-III was found to agglutinate rabbit erythrocytes, however, it caused hemolysis of pronase treated human erythrocytes. The activity of all four lectins was calcium dependent and maximum at a pH range 7-8. Apart from Gal/GalNAc specific, the four lectins showed substantial differences in their carbohydrate recognition pattern. Moreover, there was a difference in the carbohydrate specificity between AGL-III and other three lectins (AGL-IA, AGL-IB and AGL-IV) towards polyvalent glycotope. On the one hand, 'cluster glycoside effect' i.e., an enhancement of the activity of a multivalent ligand, was observed for carbohydrate specificities of AGL-IA, AGL-IB, AGL-IV. On the other hand, the effect of multivalent ligands on the carbohydrate specificity of AGL-III was opposite of cluster glycoside effect. The affinity of AGL-IA, AGL-IB and AGL-IV for ligands can be ranked as follows: glycoproteins > polysaccharide > oligosaccharides and monosaccharides. However, Gal related monosaccharides were the best inhibitors of AGL-III and the inhibitory activity decreased gradually in the following order: monosaccharide > disaccharide > polysaccharide. Thus, the

  15. Morphology, Biology, and Phylogenetic Position of the Bivalve Platomysia rugata (Heterodonta: Galeommatoidea), a Commensal with the Sipunculan Worm Sipunculus nudus.

    Science.gov (United States)

    Goto, Ryutaro; Ishikawa, Hiroshi; Hamamura, Yoichi

    2016-08-01

    The bivalve superfamily Galeommatoidea is characterized by its symbiotic associations with other marine invertebrates. However, for many galeommatoideans, the host species remains unknown. Platomysia (Galeommatoidea) is a monotypic genus including a single species P. rugata, which is distinguished from other galeommatoideans in having distinct and evenly spaced commarginal ribs on its shell surface. This species was described based on a single right valve shell collected in Nanao Bay, Japan Sea, by Habe in 1951 and has been known only from Japanese waters. However, the biology of living animals has never been reported. We found that this species lives in the burrows of the sipunculan worm Sipunculus nudus in mud flats in the Seto Inland Sea, Japan. We investigated its host association and described its shell morphology and anatomy. In addition, we performed a phylogenetic analysis using two nuclear (18S and 28S ribosomal RNA) genes to determine its phylogenetic position in Galeommatoidea. The result suggests that this species belongs to the clade of commensal bivalves together with Pseudopythina, Byssobornia, and Pergrinamor. Platomysia rugata and other two groups of sipunculan-associated galeommatoideans were not monophyletic, suggesting that association with sipunculans occurred at least three times in the galeommatoid evolution.

  16. Grazing impacts of the invasive bivalve Limnoperna fortunei (Dunker, 1857 on single-celled, colonial and filamentous cyanobacteria

    Directory of Open Access Journals (Sweden)

    V Gazulha

    Full Text Available Feeding behavior of the invasive bivalve Limnoperna fortunei in the presence of single-celled, colonial, and filamentous cyanobacteria was tested in laboratory experiments to evaluate the effects of size and shape on mussel feeding. The first hypothesis holds that golden mussel filters more efficiently smaller particles, such as single cells of Microcystis, which could be more easily assimilated by its filtering apparatus. The second hypothesis sustains that L. fortunei filters more efficiently rounded colonies, such as Microcystis, which would be more easily ingested than lengthy filamentous, such as Planktothrix. Filtration rates of golden mussel in the presence of single-celled, colonial and filamentous cyanobacteria were similar. Nevertheless, there was a great difference in the ingestion and pseudofeces production rates. Single cells were widely accepted as food, while filamentous and colonial cyanobacteria were massively expelled as pseudofeces. The results confirmed the first hypothesis that golden mussel prefers to ingest smaller particles. The second hypothesis was rejected since filamentous were preferentially ingested than colonial cyanobacteria. Golden mussel has the potential to remove toxic cells (Microcystis, however this potential would be reduced in cyanobacteria blooms, where colonial forms which are preferentially rejected by L. fortunei, are predominant. In this case, the presence of this invasive bivalve could also enhance the occurrence of blooms by rejecting colonial and filamentous cyanobacteria in pseudofeces.

  17. Polycyclic aromatic hydrocarbons in bivalves from the San Francisco estuary: Spatial distributions, temporal trends, and sources (1993-2001)

    Energy Technology Data Exchange (ETDEWEB)

    Oros, D.R.; Ross, J.R.M. [San Francisco Estuary Institute, Oakland, CA (US)

    2005-10-01

    Bivalve tissue samples were examined over a range of spatial and temporal scales (1993-2001) to determine PAH distributions, trends, and possible sources. Mussels (Mytilus californianus), oysters (Crassostrea gigas), and clams (Corbicula fluminea) were deployed for three months in the estuary at stations remote from known point source discharges. The range of {Sigma} PAH detected in bivalves was oysters 184-6899 mu g/kg dry wt (mean 678 {mu}g/kg dry wt), mussels 21-1093 {mu}g/kg dry wt (mean 175 {mu}g/kg dry wt), and clams 78-720 {mu}g/kg dry wt (mean 323 {mu}g/kg dry wt). Linear regression analysis showed no statistically significant (P {gt} 0.05) temporal trends in clam and mussel {Sigma}PAH at any of the deployment stations or estuary segments. On the other hand, a statistically significant (p {lt} 0.05) decreasing trend was found in {Sigma}PAH in oysters at the Petaluma River station, and in the North Estuary segment. PAH isomer pair ratios applied as diagnostic indicators suggested that the bioaccumulated PAH were derived primarily from petroleum combustion, with lesser amounts derived from biomass and coal combustion, and unburned petroleum.

  18. Reclassification of the larval pathogen for marine bivalves Vibrio tubiashii subsp. europaeus as Vibrio europaeus sp. nov.

    Science.gov (United States)

    Dubert, Javier; Romalde, Jesús L; Spinard, Edward J; Nelson, David R; Gomez-Chiarri, Marta; Barja, Juan L

    2016-11-01

    The Orientalis clade has a relevant significance for bivalve aquaculture since it includes the pathogens Vibrio bivalvicida, Vibrio tubiashii subsp. tubiashii and Vibrio tubiashii subsp. europaeus. However, the previous taxonomic description of the subspecies of V. tubiashii shows some incongruities that should be emended. In the genomic age, the comparison between genome assemblies is the key to clarify the taxonomic position of both subspecies. With this purpose, we have tested the ability of multilocus sequence analysis based on eight housekeeping gene sequences (gapA, gyrB, ftsZ, mreB, pyrH, recA, rpoA and topA), different in silico genome-to-genome comparisons, chemotaxonomic features and phenotypic traits to reclassify the subspecies V. tubiashii subsp. europaeus within the Orientalis clade. This polyphasic approach clearly demonstrated that this subspecies is phylogenetically and phenotypically distinct from V. tubiashii and should be elevated to the rank of species as Vibrio europaeus sp. nov. This reclassification allows us to update the Orientalis clade (V. bivalvicida,V. brasiliensis, V. crosai, V. hepatarius, V. orientalis, V. sinaloensis, V. tubiashii and V. europaeus sp. nov.) and reconstruct a better phylogeny of the genus Vibrio. An emended description of V. tubiashii is provided. Finally, the proposed novel species is represented by emergent bivalve pathogens [type strain PP-638T (=CECT 8136T=DSM 27349T), PP2-843 and 07/118 T2] responsible for high mortalities in Spanish and French hatcheries.

  19. Early and late lithification of aragonitic bivalve beds in the Purbeck Formation (upper jurassic-lower cretaceous) of Southern England

    Science.gov (United States)

    El-Shahat, Adam; West, Ian

    1983-05-01

    Beds of euryhaline bivalves alternating with shales constitute much of the middle Purbeck Formation. They originated on "tidal" flats at the western margin of an extensive brackish lagoon. When these shell beds are thin and enclosed in shale they are often still preserved as aragonite and are associated with "beef", fibrous calcite formed during compaction. In most cases, however, the shell debris has been converted by diagenesis into calcitic biosparrudite limestones. A compacted type has been lithified at a late stage, after deep burial. In this, pyrite is abundant and most of the shell aragonite has been replaced neomorphically by ferroan pseudopleochroic calcite. A contrasting uncompacted type of biosparrudite is characterised by bivalve fragments with micrite envelopes. Shells and former pores are occupied by non-ferroan sparry calcite cement, and there is little pyrite. These limestones frequently contain dinosaur footprints and originated in "supratidal" environments where they were cemented early, mainly in meteoric water. Once lithified they were unaffected by compaction. This uncompacted type indicates phases of mild uplift or halts in subsidence. These shell-bed lithologies, and also intermediate types described here, will probably be recognised in other lagoonal formations.

  20. Biomarkers of metabolism disturbance in bivalve molluscs induced by environmental pollution with processed by-products of oil

    Directory of Open Access Journals (Sweden)

    E. V. Sukharenko

    2017-05-01

    Full Text Available Processed by-products of oil are the most common pollutants in all river and sea water. The increase in oxidative stress in bivalve molluscs was studied in both tissues of the hepatopancreas and the gill. The model for artificial treatment with processed by-products of oil was performed in a laboratory experiment with the river mollusc Dreissena polymorpha Pallas, 1771. The exposure of the molluscs over 28 days to mazut 50 mg/l induced significant increase of both final product of lipid peroxidation (LPO and antioxidant enzime activity. A significant increase in LPO was observed in the hepatopancreas and gill of D. polymorpha treated with mazut compared to the control group. Antioxidant enzyme activity of cartalase, supeoxide dismutase, glutathione reductase and glutathione-S-transferase showed a greater increase (by almost 1.5 times in the hepatopancreas than in the gill of D. polymorpha. A similar LPO growth and modulation of antioxidant enzyme activity were determined in the hepatopancreas and gill of the mussel Mytilus galloprovincialis Lamarck, 1879 collected in an area polluted with resins, hydrocarbons and asphaltenes, Donuzlav lake in the Kerch gulf. Varied cellular reactivation of the antioxidant enzyme system in the hepatopancreas rather than the gill was observed in both kinds of mollusc Dreissena and Mytilus. The obtained results are evidence of the higher sensitivity of the hepatopancreas cells of bivalve molluscs to organic pollutants compared to the gill cells.

  1. Growth rates and geochemical proxies in Late Campanian bivalves - New insights from micro-X-ray Fluorescence mapping and numerical growth modelling

    Science.gov (United States)

    de Winter, Niels; Goderis, Steven; van Malderen, Stijn; Vanhaecke, Frank; Claeys, Philippe

    2017-04-01

    Understanding the Late Cretaceous greenhouse climate is of vital importance for understanding present and future climate change. While a lot of good work has been done to reconstruct climate in this interesting period, most paleoclimatic studies have focused on long-term climate change[1]. Alternatively, multi-proxy records from marine bivalves provide us with a unique opportunity to study past climate on a seasonal scale. However, previous fossil bivalve studies have reported ambiguous results with regard to the interpretation of trace element and stable isotope proxies in marine bivalve shells[2]. One major problem in the interpretation of such records is the bivalve's vital effect and the occurrence of disequilibrium fractionation during bivalve growth. Both these problems are linked to the annual growth cycle of marine bivalves, which introduces internal effects on the incorporation of isotopes and trace elements into the shell[3]. Understanding this growth cycle in extinct bivalves is therefore of great importance for the interpretation of seasonal proxy records in their shells. In this study, three different species of extinct Late Campanian bivalves (two rudist species and one oyster species) that were found in the same stratigraphic interval are studied. Micro-X-Ray Fluorescence line scanning and mapping of trace elements such as Mg, Sr, S and Zn, calibrated by LA-ICP-MS measurements, is combined with microdrilled stable carbon and oxygen isotope analysis on the well-preserved part of the shells. Data of this multi-proxy study is compared with results from a numerical growth model written in the open-source statistics package R[4] and based on annual growth increments observed in the shells and shell thickness. This growth model is used together with proxy data to reconstruct rates of trace element incorporation into the shell and to calculate the mass balance of stable oxygen and carbon isotopes. In order to achieve this goal, 2D mapping of bivalve shell

  2. [Streptococcus suis infection--clinical manifestations].

    Science.gov (United States)

    Dragojlović, Julijana; Milosević, Branko; Sasić, Neda; Pelemis, Mijomir; Sasić, Milan

    2005-01-01

    Streptococcus suis is a bacterium causing a disease in pigs and rarely in humans. This zoonosis is mostly found as a sporadic disease in individuals that were in contact with the affected or infected pigs: farmers, veterinarians and workers engaged in fresh pork processing. It is assumed that the bacterium enters the body through a cut abrasion in the skin. Initially, the condition resembles a flu, followed by signs of bacteriemia and sepsis. The most frequent clinical manifestation of Streptococcus suis infection is meningitis, leading to hearing loss in over 75% of patients, and subsequent arthritis, endophtalmitis, endocarditis and pneumonia. Toxic shock syndrome with hemorhagic manifestations rarely develops. This study included five male patients aged 22 to 63 years treated in the Intensive Care Unit of the Institute of Infectious and Tropical Diseases in Belgrade, due to Streptococcus suis infection. The aim of this study was to point to the existence of this bacteria in our environment, to describe clinical manifestations of the disease and to point out the importance of its prevention. All patients had epidemiological evidence of being in contact with pork meat. There were no data about diseased pigs. The estimated incubation period was 4 to 8 days. All patients had meningeal signs. Clinical symptoms included shivering, fever, vomiting, headache, malaise, vertigo and tinitus. Three patients presented with alerterd level of awarrness. Four patients developed very severe bilateral hearing impairment, whereas one endophtalmtis and one developed endocarditis. The cerebrospinal fluid (CSF) was opalescent in four patients, and only one patient presented with clear CSF. CSF examination showed typical changes characteristic for bacterial meningitis. Streptoccocus suis was isolated in CSF in all patients, and in one patient the bacteria was isolated in blood as well. All patients underwent treatement with II and III generation cephalosporins and one with one

  3. 78 FR 11877 - Announcement of Requirements Gathering Meetings for the Electronic Manifest (e-Manifest) System

    Science.gov (United States)

    2013-02-20

    ... process, including enabling better transparency by sharing data with the public at appropriate stages..., members of industry who use the manifest indicated that they would be willing to help pay the costs of such a system, perhaps through the assessment of reasonable service fees or by a similar ``user pays...

  4. Neurological manifestations of Chikungunya and Zika infections

    Directory of Open Access Journals (Sweden)

    Talys J. Pinheiro

    Full Text Available ABSTRACT The epidemics of Chikungunya virus (CHIKV and Zika virus (ZIKV infections have been considered the most important epidemiological occurrences in the Americas. The clinical picture of CHIKV infection is characterized by high fever, exanthema, myalgia, headaches, and arthralgia. Besides the typical clinical picture of CHIKV, atypical manifestations of neurological complications have been reported: meningo-encephalitis, meningoencephalo-myeloradiculitis, myeloradiculitis, myelitis, myeloneuropathy, Guillain-Barré syndrome and others. The diagnosis is based on clinical, epidemiological, and laboratory criteria. The most common symptoms of ZIKV infection are skin rash (mostly maculopapular, fever, arthralgia, myalgia, headache, and conjunctivitis. Some epidemics that have recently occurred in French Polynesia and Brazil, reported the most severe conditions, with involvement of the nervous system (Guillain-Barré syndrome, transverse myelitis, microcephaly and meningitis. The treatment for ZIKV and CHIKV infections are symptomatic and the management for neurological complications depends on the type of affliction. Intravenous immunoglobulin, plasmapheresis, and corticosteroid pulse therapy are options.

  5. Atypical Radiological Manifestation of Pulmonary Metastatic Calcification

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Eun Hae; Kim, Eun Sun; Kim, Chul Hwan; Ham, Soo Youn; Oh, Yu Whan [Korea University College of Medicine, Seoul (Korea, Republic of)

    2008-04-15

    Metastatic pulmonary calcification is a condition of calcium deposition in the normal pulmonary parenchyma, and this is secondary to abnormal calcium metabolism without any prior soft tissue damage. The predisposing factors for this condition include chronic renal failure, hypercalcemia and increased tissue alkalinity. The most common radiologic manifestation consists of poorly defined nodular opacities in the upper lung zone. These opacities reflect the deposition of calcium salts in the pulmonary interstitium. We present here a case of metastatic pulmonary calcification in a patient who recovered from pneumonia with sepsis and whose high-resolution CT (HRCT) images demonstrated localized parenchymal airspace calcification that was limited to the bilateral lower lobes. These lower lobes had been involved with pneumonic consolidation without calcification, as seen on the previous CT scan. In summary, we report here on an atypical presentation of metastatic pulmonary calcification that showed dense airspace consolidation localized to the bilateral lower lobes in a patient with primary hyperparathyroidism and pneumonia.

  6. Loop Amplitude Diagrams in Manifest, Maximal Supergravity

    Science.gov (United States)

    Karlsson, Anna

    The issue of finiteness of maximal supergravity has been subject to research for quite some time. Here, we approach that question through an examination of how to describe amplitude diagrams in D = 11 maximal supergravity from a field theory point of view. The strength of the formulation is the presence of manifest supersymmetry through the use of pure spinors. An initial analysis of what the subsequent characteristics turn out to be, partly in lower dimensions through dimensional reduction, gives at hand results that agree with previous work, pointing towards a first divergence for the 7-loop contribution to the 4-point amplitude in four dimensions. The text is mainly based on and may be regarded as an introduction to the main points presented there.

  7. Type 1 neurofibromatosis with periodontal manifestations

    Directory of Open Access Journals (Sweden)

    Pramod Kumar

    2016-01-01

    Full Text Available Neurofibromatosis type 1 (NF1 also known as von Recklinghausen's disease is an autosomal dominant disease transmitted with a high degree of penetrance. The disease is expressed in different forms. NF1 accounts for almost 90% of the cases although nine types have been described to date. We report one such case of a 36-year-old female who presented with multiple nodules on the body. He was diagnosed to have NF1, having satisfied the diagnostic criteria for the same. Oral manifestations can be found in almost 72% of NF1 patients. This case report highlights the clinical features and diagnostic criteria of NF1, the prevalence and the significance of intraoral neurofibromas and the need for the dental practitioner to be aware of this condition.

  8. Skin manifestations of chronic kidney disease.

    Science.gov (United States)

    Robles-Mendez, J C; Vazquez-Martinez, O; Ocampo-Candiani, J

    2015-10-01

    Skin manifestations associated with chronic kidney disease are very common. Most of these conditions present in the end stages and may affect the patient's quality of life. Knowledge of these entities can contribute to establishing an accurate diagnosis and prognosis. Severe renal pruritus is associated with increased mortality and a poor prognosis. Nail exploration can provide clues about albumin and urea levels. Nephrogenic systemic fibrosis is a preventable disease associated with gadolinium contrast. Comorbidities, such as diabetes mellitus and secondary hyperparathyroidism, can lead to acquired perforating dermatosis and calciphylaxis, respectively. Effective and innovative treatments are available for all of these conditions. Copyright © 2015 Elsevier España, S.L.U. and AEDV. All rights reserved.

  9. Cutaneous Manifestations of Human and Murine Leishmaniasis.

    Science.gov (United States)

    Scorza, Breanna M; Carvalho, Edgar M; Wilson, Mary E

    2017-06-18

    The leishmaniases are diseases caused by pathogenic protozoan parasites of the genus Leishmania. Infections are initiated when a sand fly vector inoculates Leishmania parasites into the skin of a mammalian host. Leishmania causes a spectrum of inflammatory cutaneous disease manifestations. The type of cutaneous pathology is determined in part by the infecting Leishmania species, but also by a combination of inflammatory and anti-inflammatory host immune response factors resulting in different clinical outcomes. This review discusses the distinct cutaneous syndromes described in humans, and current knowledge of the inflammatory responses associated with divergent cutaneous pathologic responses to different Leishmania species. The contribution of key hematopoietic cells in experimental cutaneous leishmaniasis in mouse models are also reviewed and compared with those observed during human infection. We hypothesize that local skin events influence the ensuing adaptive immune response to Leishmania spp. infections, and that the balance between inflammatory and regulatory factors induced by infection are critical for determining cutaneous pathology and outcome of infection.

  10. Spiral CT manifestations of spherical pneumonia

    International Nuclear Information System (INIS)

    Li Xiaohong; Yang Hongwei; Xu Chunmin; Qin Xiu

    2008-01-01

    Objective: To explore the Spiral CT manifestations and differential diagnosis of spherical pneumonia. Methods: 18 cases of spherical pneumonia and 20 cases of peripheral pulmonary carcinoma were selected, both of them were confirmed by clinic and/or pathology. The SCT findings of both groups were compared retrospectively. Results: Main spiral CT findings of spherical pneumonia were showed as followings: square or triangular lesions adjacent to pleura; with irregular shape, blurry, slightly lobulated margin, sometimes with halo sign. Small inflammatory patches and intensified vascular markings around the lesions were seen. Lesions became smaller or vanished after short-term anti-inflammatory treatment. Conclusion: Spherical pneumonia showed some characteristics on Spiral CT scan, which are helpful in diagnosis and differential diagnosis of this disease. (authors)

  11. Musculoskeletal manifestations in sickle cell anemia

    Directory of Open Access Journals (Sweden)

    Reddy Ravikanth

    2017-01-01

    Full Text Available Sickle cell anemia is an inherited hemoglobin disorder characterized by substitution of glutamic acid by valine at the sixth position of the beta globin chain. The sequence of events leads to pain crisis. Ischemia of the tissues resulting from decreased blood flow is believed to occur in pain crisis. Repeated or prolonged sickling causes red cell death in the form of hemolytic anemia. The majority of hospital admissions are due to painful crisis. These patients are at increased risk for both osteomyelitis and infarction of the long bones. Magnetic resonance imaging has been shown to be helpful in the diagnosis of early osteomyelitis and its differentiation from infarction in sickle cell disease patients with acute bone crisis. Others findings include dactylitis, medullary infarcts, diploic space widening, fish mouth vertebrae, and avascular necrosis. We present a case series on the various musculoskeletal manifestations of sickle cell disease.

  12. [Digestive manifestations in acquired immunodeficiency disease].

    Science.gov (United States)

    Girard, P M; Marche, C; Maslo, C; Rene, E; Leport, J; Matheron, S; Michon, C; Coulaud, J P; Saimot, A G

    1987-01-01

    Digestive manifestations of AIDS were studied retrospectively in 87 patients with respect to clinical, microbiological, endoscopic and histological data. Chronic or intermittent diarrhea was observed in 62 p. 100 of patients and frequently associated with major weight loss. The digestive opportunistic infections were: oesophageal candidiasis (42 p. 100), cryptosporidiosis (24 p. 100), cytomegalovirus infections (22 p. 100), isosporiasis (3.4 p. 100), atypical mycobacteriosis (2.2 p. 100), toxoplasmosis (2.2 p. 100). Thirty non-opportunistic agents were detected in 26 patients. Gastrointestinal Kaposi sarcoma occurred in 18 p. 100 of cases. The etiology of diarrhea remained unknown in 16 p. 100 of patients. The value of endoscopy is discussed: esophagogastroduodenal fibroscopy, is usually required to assess oesophageal candidiasis, colonoscopy is required to assess cytomegalovirus colitis on histological data.

  13. Are the cutaneous manifestations in patients with primary antiphospholipid syndrome a marker for predicting lung manifestations?

    Science.gov (United States)

    Kontic, Milica; Stojanovich, Ljudmila; Mijailović-Ivković, Milena; Velinović, Mladen; Srnka, Jasminka; Zdravkovic, Marija

    2018-01-01

    The aim of this study was to investigate association between pulmonary and skin manifestations in a large group of patients with primary antiphospholipid syndrome (PAPS) as well as their connection with antiphospholipid antibodies. Our prospective study comprises of 390 patients with primary APS. Antiphospholipid antibody (aPL) analysis included detection of aCL (IgG/IgM), ß2GPI (IgG/IgM) and LA. Distinct pulmonary and skin associations were determined, as well as their associations with aPL. In PAPS patients the presence of LA was more common in PTE (p=0.005) and in pulmonary microthrombosis (p=0.003). We revealed statistical significance considering the presence of aCL IgM and pulmonary microthrombosis (p=0.05). Skin ulcerations correlated with positive titres aCL IgM and ß2 GPI IgM (p=0.03 and 0.04, respectively), while pseudovasculitis correlated with positive titres ß2 GPI IgM (p=0.02). PAPS patients were more more likely to develop pulmonary thromboembolisam if they had livedo reticularis (p=0.005), skin ulcerations (p=0.007), pseudovasculitic lesions (p=0.01), superficial cutaneous necrosis (p=0.005), and digital gangrene (p=0.02). Patients were also more prone to pulmonary microthrombosis if they already had livedo reticularis (p=0.03), skin ulcerations (p=0.007), pseudovasculitic lesions (p=0.05), superficial cutaneous necrosis (p=0.006), and digital gangrene (p=0.02). There is strong link between some pulmonary and skin manifestations in PAPS patients, suggesting complexity and evolutionary nature of APS. The presence of skin manifestations may be a high risk factor for several types of serious pulmonary manifestations in PAPS. Certain aPL types are associated with distinct pulmonary and skin manifestation, suggesting their predictive role.

  14. Pulmonary manifestations of granulomatosis with polyangiitis.

    Science.gov (United States)

    Gómez-Gómez, Alejandro; Martínez-Martínez, Marco Ulises; Cuevas-Orta, Enrique; Bernal-Blanco, Juan Mario; Cervantes-Ramírez, Daniel; Martínez-Martínez, Raúl; Abud-Mendoza, Carlos

    2014-01-01

    To describe the clinical and laboratory data, with special emphasis on thoracic imaging findings, in 14 patients with a definitive diagnosis of granulomatosis with polyangiitis (GPA). The clinical and tomographic data of 14 patients with a definitive diagnosis of GPA are presented. Patients with thoracic manifestations suggestive of GPA were evaluated in 3 hospitals from 2000 to 2012. All patients had a sputum analysis and bronchoalveolar lavage for bacterial, mycobacterial and fungal stains and cultures; antineutrophil cytoplasmic antibodies, antinuclear-antibodies, rheumatoid factor, and a biopsy of involved organs. A total of 13 patients had at least two organs involved. The most frequent thoracic findings were pulmonary nodules, ground glass opacities and patches of consolidation; other abnormalities were tracheal stenosis, diffuse alveolar hemorrhage, lung masses with organized pneumonia. More than three-quarters (78%) of patients had positive antineutrophil cytoplasmic antibodies (ANCA). Ten patients had respiratory tissue biopsy (8 open lung, one tracheal, and one nasal). In 4 patients the diagnosis was made with the classic organ involvement in GPA, positive ANCA, and renal or skin biopsy, and response to treatment on follow-up. At 6-12 months all patients showed clinical and radiological improvement, with 54% showing a recurrence of disease. The majority of thoracic findings described in GPA are presented in this study. A complete diagnostic approach with invasive diagnostic procedures to rule out other more prevalent respiratory diseases with similar thoracic manifestations must be performed. The positivity of ANCA in this study was high, and the recurrence of the disease was frequent. Copyright © 2013 Elsevier España, S.L.U. All rights reserved.

  15. Nocturia as a manifestation of systemic disease.

    Science.gov (United States)

    Gulur, Dev Mohan; Mevcha, Amit M; Drake, Marcus J

    2011-03-01

    Nocturia is commonly referred to urologists, but the mechanisms underlying the problem, together with the appropriate clinical assessment and management, may lie outside the ordinary scope of the specialty. Some serious conditions may manifest nocturia as an early feature, often as a consequence of nocturnal polyuria (NP). Voiding frequency is influenced by rate of urine output, reservoir capacity of the bladder, lower urinary tract (LUT) sensation and psychological response. Polyuria can result from polydipsia or endocrine dysfunction. NP can result from endogenous fluid and solute shifts, cardiovascular and autonomic disease, obstructive sleep apnoea, and chronic kidney disease. Nocturia without polyuria occurs in the presence of LUT pathology, pelvic masses and sleep disturbance. Drug intake can contribute to, or counteract, each of these problems. In assessing nocturia, clinicians need to consider an undiagnosed serious condition that may manifest nocturia as an early feature, or suboptimal management of a known condition. The frequency-volume chart is a key tool in categorizing the basis of nocturia, identifying those patients with global polyuria or NP, for whom involvement of other specialties is often necessary for assessment and management. Treatment should be directed at the cause of the problem, with a view to improving long-term health and health-related quality of life. Simple steps should be undertaken by all patients, including improvement of the sleep environment and behaviour modification. Evaluation of treatment response requires objective data to corroborate subjective impressions. Some mechanisms of nocturia do not reliably improve with treatment, leading to refractory symptoms. © 2010 THE AUTHORS. BJU INTERNATIONAL © 2010 BJU INTERNATIONAL.

  16. [Osteo-articular manifestations of sarcoidosis].

    Science.gov (United States)

    Alaoui, Fatima-Zohra; Talaoui, Maha; Benamour, Saida

    2005-01-15

    Osteo-articular sarcoidosis may be evoked in the presence of peripheral articular manifestations or bone lesions that are sometimes asymptomatic. The aim of this work is to describe clinical and progressive features of sarcoidosis with osteo-articular involvement. Our retrospective study concerned 18 patients presenting with osteo-articular sarcoidosis from 1985 to 1999. We included patients with clinical diagnosis suggestive of sarcoidosis and with at least one positive biopsy. Among 35 cases of sarcoidosis, 18 patients had an osteo-articular manifestation (51.42%), which revealed the disease in 2 patients. The female sex was predominant (sex ratio M/F of 0.12), the mean age was 47 years and the time before diagnosis was 3.6 years. Articular involvement was the most frequent. Inflammatory joint pains were present in 11 cases, a Lofgren syndrome in 2 cases, a chronic arthritis in 4 cases and acute monoarthritis of the elbow in 1 case. A female patient exhibited a probable association with a spondylarthropathy. The bone involvement, revealing the disease in 1 case, was also noted in 5 cases, located exclusively on hands; this sarcoidosal dactyly was represented in 2 cases in the form of phalangeal geodes, in wired form (2 cases) and in large bulla form (1 case). The bone biopsy when it was performed was positive in all 3 cases. The patients responded well to corticosteroids. The osteo-articular involvement of sarcoidosis is polymorphic and can reveal the disease or may appear during the course of its progression.

  17. Late Devonian (Frasnian) bivalves from the Nocedo Formation: the results of Wilhelm Kegel’s 1927 field trip to northern Spain

    NARCIS (Netherlands)

    Amler, M.R.W.

    2010-01-01

    During a field trip to the Peña-Corada Unit of the southernmost Esla region of the Cantabrian Mountains in 1927, the German stratigrapher Wilhelm Kegel sampled brachiopods and bivalves from a section in the Laoz valley near La Ercina. The stratigraphic position is believed to be part of the Nocedo

  18. Description of the Bivalve Littigiella pacifica n. sp. (Heterodonta: Galeommatoidea: Lasaeidae), Commensal with the Sipunculan Sipunculus nudus from the Ryukyu Islands, Japan

    DEFF Research Database (Denmark)

    Lützen, Jørgen; Kosuge, Takeharu

    2006-01-01

    In the Ryukyu Islands, Japan, Litigiella pacifica n. sp. lives attached to the body of the burrowing sipunculan Sipunculus nudus. The morphology of the shell and the soft parts are described and compared with other bivalve commensal with the same sipunculan. The new species is hermaphroditic...

  19. Predation on O-group and older year classes of the bivalve Macoma balthica : interaction of size selection and intertidal distribution of epibenthic predators

    NARCIS (Netherlands)

    Hiddink, JG; Marijnissen, SAE; Troost, K; Wolff, WJ

    2002-01-01

    The bivalve Macoma balthica is a common species in the Wadden Sea and North Sea. Juveniles temporarily use nurseries in the high intertidal. To explain this nursery use, predation pressure was examined for both juvenile and adult Macoma at low and high tidal flats. The study was carried out in the

  20. Systematics, functional morphology and distribution of a bivalve (Apachecorbula muriatica gen. et sp. nov.) from the rim of the 'Valdivia Deep' brine pool in the Red Sea

    KAUST Repository

    Oliver, Pere Graham

    2014-11-11

    The deep brine pools of the Red Sea comprise extreme, inhospitable habitats yet house microbial communities that potentially may fuel adjacent fauna. We here describe a novel bivalve from a deep-sea (1525 m) brine pool in the Red Sea, where conditions of high salinity, lowered pH, partial anoxia and high temperatures are prevalent. Remotely operated vehicle (ROV) footage showed that the bivalves were present in a narrow (20 cm) band along the rim of the brine pool, suggesting that it is not only tolerant of such extreme conditions but is also limited to them. The bivalve is a member of the Corbulidae and named Apachecorbula muriatica gen. et sp. nov. The shell is atypical of the family in being modioliform and thin. The semi-infaunal habit is seen in ROV images and reflected in the anatomy by the lack of siphons. The ctenidia are large and typical of a suspension feeding bivalve, but the absence of \\'guard cilia\\' and the greatly reduced labial palps suggest that it is non-selective as a response to low food availability. It is proposed that the low body mass observed is a consequence of the extreme habitat and low food availability. It is postulated that the observed morphology of Apachecorbula is a result of paedomorphosis driven by the effects of the extreme environment on growth but is in part mitigated by the absence of high predation pressures. © Marine Biological Association of the United Kingdom, 2014.

  1. Biomonitoring of Heavy metals using the bivalve molluscs in sunderban mangrove wetland, Northeast Coast of Bay of bengal (india): possible risks to Human health

    Energy Technology Data Exchange (ETDEWEB)

    Cabral, Henrique; Cardoso, Ines [Departamento de Biologia Animal/Instituto de Oceanografia, Campo Grande, Lisboa (Portugal); Chatterjee, Mousumi; Kumar Bhattacharya, Asok; Aftab Alam, Mohammad [Department of Marine Science, University of Calcutta, Calcutta (India); Kanta Satpathy, Kamala [Indira Gandhi Centre for Atomic Research, Environmental and Industrial Safety Section, Safety Group, Kalpakkam, Tamil Nadu (India); Kumar Sarkar, Santosh

    2008-02-15

    The suitability of using four bivalve molluscs (Sanguinolaria acuminata, Anadara granosa, Meretrix meretrix, and Pelecyora trigona) in biomonitoring of heavy metals (Cu, Pb, Cd, Zn, and Hg) collected from intertidal regions of the Sunderban mangrove wetland, northeastern part of the Bay of Bengal, were evaluated. Both speciesdependent variability and temporal variations were pronounced. A high degree of organ specificity was evident in the bivalves where gill and mantle exhibited higher metal accumulation due to ion exchange property of the mucous layer covering these organs while shells represent very poor accumulation. Elevated values of Zn and Cu reflect high potential for biomagnification through marine food chain. Metal concentrations in different body size groups of the bivalves do not follow uniform trend. Correlation coefficient between different metal couplings as tested statistically revealed significant coupling for Pb-Zn, Pb-Cu, Zn-Cu, and Hg-Cu. Concentrations of all the metals in specific organs (visceral mass, mantle and gill) of the bivalves exceeded the safe levels according to the international standards for metals compiled by Food and Agricultural Organization of the United Nations and would be of great risk for human consumption. It is concluded that the mussel and clam are suitable biomonitors to employ in programs designed to assess changes in metal pollution in the Sunderban mangrove wetland. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

  2. Paleoecology and paleoenvironments of Permian bivalves of the Serra Alta Formation, Brazil: Ordinary suspension feeders or Late Paleozoic Gondwana seep organisms?

    Science.gov (United States)

    Matos, Suzana Aparecida; Warren, Lucas Verissimo; Fürsich, Franz Theodor; Alessandretti, Luciano; Assine, Mario Luis; Riccomini, Claudio; Simões, Marcello Guimarães

    2017-08-01

    This is the first record of a Permian seep deposit and an associated, morphologically bizarre, bivalve-dominated fauna from the Passa Dois Group, Paraná Basin, Brazil. Shales of the outer-shelf facies of the Serra Alta Formation preserve a low-diversity but high-abundant, large-sized bivalve fauna with unusual morphologies inside discoidal carbonate concretions. The bivalves are about ten times larger than tiny bivalves found scattered in laterally equivalent mudstones of the same unit. Intercalated between two concretion-bearing horizons, a cm-thick, sheet-like, disrupted, ;brecciated;, partially silicified carbonate layer with microbially-induced lamination is recorded. In some areas, the carbonate layer shows vertical structures formed by injections of mud mixed with white limestone clasts and microbial linings. Immediately above this, silicified mudstones preserve small domal structures (= mounds) with a slightly depressed center. Monospecific concentrations of closed articulated shells of Tambaquyra camargoi occur at the base of these domes. Carbon-isotope (δ13C) values from the shells, ;brecciated; carbonates, and fossil-rich concretions are all depleted (negative values ∼ -6.1 to -7.6‰). Combined taphonomic, sedimentological, petrographic, geochemical and paleontological data suggest that the disrupted, ;brecciated; carbonate and associated fauna and domes may have formed by an exudation system. Indeed, this interval of the Serra Alta Formation is ∼8.7 m above the contact with the underlying, oil-rich Irati Formation. This unit has very high total organic carbon (up to 23%) values and high sulphur contents, supporting the interpretation of the lithological and paleontological features as result of seepage of organic compounds at the seafloor. Where the gases and hydrocarbons escaped, the seabed was colonized by, at least facultatively, chemosymbiotic bivalves. The species above belong to a highly endemic group of pachydomids that were shallow

  3. Short- and long-term consequences of larval stage exposure to constantly and ephemerally elevated carbon dioxide for marine bivalve populations

    Directory of Open Access Journals (Sweden)

    C. J. Gobler

    2013-04-01

    Full Text Available While larval bivalves are highly sensitive to ocean acidification, the basis for this sensitivity and the longer-term implications of this sensitivity are unclear. Experiments were performed to assess the short-term (days and long-term (months consequences of larval stage exposure to varying CO2 concentrations for calcifying bivalves. Higher CO2 concentrations depressed both calcification rates assessed using 45Ca uptake and RNA : DNA ratios in Mercenaria mercenaria and Argopecten irradians larvae with RNA : DNA ratios being highly correlated with larval growth rates (r2>0.9. These findings suggested that high CO2 has a cascading negative physiological impact on bivalve larvae stemming in part from lower calcification rates. Exposure to elevated CO2 during the first four days of larval development significantly depressed A. irradians larval survival rates, while a 10-day exposure later in larval development did not, demonstrating the extreme CO2 sensitivity of bivalve larvae during first days of development. Short- (weeks and long-term (10 month experiments revealed that individuals surviving exposure to high CO2 during larval development grew faster when exposed to normal CO2 as juveniles compared to individuals reared under ambient CO2 as larvae. These increased growth rates could not, however, overcome size differences established during larval development, as size deficits of individuals exposed to even moderate levels of CO2 as larvae were evident even after 10 months of growth under normal CO2 concentrations. This "legacy effect" emphasizes the central role larval stage CO2 exposure can play in shaping the success of modern-day bivalve populations.

  4. Cephalic and limb anatomy of a new Isoxyid from the Burgess Shale and the role of "stem bivalved arthropods" in the disparity of the frontalmost appendage.

    Science.gov (United States)

    Aria, Cédric; Caron, Jean-Bernard

    2015-01-01

    We herein describe Surusicaris elegans gen. et sp. nov. (in Isoxyidae, amended), a middle (Series 3, Stage 5) Cambrian bivalved arthropod from the new Burgess Shale deposit of Marble Canyon (Kootenay National Park, British Columbia). Surusicaris exhibits 12 simple, partly undivided biramous trunk limbs with long tripartite caeca, which may illustrate a plesiomorphic "fused" condition of exopod and endopod. We construe also that the head is made of five somites (= four segments), including two eyes, one pair of anomalocaridid-like frontalmost appendages, and three pairs of poorly sclerotized uniramous limbs. This fossil may therefore be a candidate for illustrating the origin of the plesiomorphic head condition in euarthropods, and questions the significance of the "two-segmented head" in, e.g., fuxianhuiids. The frontalmost appendage in isoxyids is intriguingly disparate, bearing similarities with both dinocaridids and euarthropods. In order to evaluate the relative importance of bivalved arthropods, such as Surusicaris, in the hypothetical structuro-functional transition between the dinocaridid frontal appendage and the pre-oral-arguably deutocerebral-appendage of euarthropods, we chose a phenetic approach and computed morphospace occupancy for the frontalmost appendages of 36 stem and crown taxa. Results show different levels of evolutionary decoupling between frontalmost appendage disparity and body plans. Variance is greatest in dinocaridids and "stem bivalved" arthropods, but these groups do not occupy the morphospace homogeneously. Rather, the diversity of frontalmost appendages in "stem bivalved" arthropods, distinct in its absence of clear clustering, is found to link the morphologies of "short great appendages," chelicerae and antennules. This find fits the hypothesis of an increase in disparity of the deutocerebral appendage prior to its diversification in euarthropods, and possibly corresponds to its original time of development. The analysis of this

  5. New lucinid bivalves from shallow and deeper water of the Indian and West Pacific Oceans (Mollusca, Bivalvia, Lucinidae

    Directory of Open Access Journals (Sweden)

    John Taylor

    2013-08-01

    Full Text Available Four new species and a new genus of lucinid bivalves are described from shallow and deeper waters in the Indian and West Pacific Oceans. The new genus Scabrilucina (subfamily Lucininae includes the little-known S. victorialis (Melvill, 1899 from the Arabian Sea and S. vitrea (Deshayes, 1844 from the Andaman Sea as well as a new species S. melvilli from the Torres Strait off northeastern Australia. Ferrocina brunei new species (Lucininae was recovered from 60 m near oil drilling activities off Borneo; its anatomy confirmed the presence of symbiotic bacteria. Two unusual deeper water species of Leucosphaerinae are described, both species included in on-going molecular analyses; Gonimyrtea ferruginea from 400–650 m in the southwest Pacific and Myrtina reflexa from 200–825 m off Zanzibar and Madagascar.

  6. The vertical distribution and abundance of gastropods and bivalves from rocky beaches of Cuastecomate Bay, Jalisco. México

    Directory of Open Access Journals (Sweden)

    M. C Esqueda

    2000-12-01

    Full Text Available The vertical distribution and abundance of conspicuous gastropod and bivalve species were studied at five rocky beaches in Cuastecomate Bay, Jalisco. Sampling was done from September, 1993 through March, 1994 with 0.75 m2 quadrants placed along replicate transect lines (10 m long in the supralittoral and mesolittoral (upper, middle and lower intertidal zones. A total of 6 643 mollusks were collected. Gastropods dominated the samples (6 272 individuals, 44 species; the bivalves were less abundant and diverse (371 individuals, five species. Seventeen species comprised 89.8% of all individuals collected. The gastropods Nodilittorina aspera and Nerita scabricosta were the most abundant with 637.8 and 71.43 individuals/m2, respectively. The most abundant bivalves were Brachidontes adamsianus and Chloromytilus palliopunctatus with 60.7 and 61.3 individuals/m2 respectively. The abundance of gastropods decreased from the supralittoral to the lower tidal zones while the number of species increased in the same direction. The number of species of bivalves also increased from the supralittoral to the lower intertidal zone; the abundance of individuals was higher at the middle intertidal zone. Affinities between groups of species among sampling stations were identified by computing Pearson’s correlation coefficient using abundance values (ind./m2 and Jaccard's dissimilarity index using species presence or absence in the lower intertidal zone. Affinity among stations was not dependent upon their vicinity but on the high dominance of few species, the occurrence of many secondary species and beach characteristics.Se presenta la distribución y abundancia de las especies conspicuas de gastrópodos y bivalvos encontradas en cinco playas rocosas de la Bahía Cuatecomate, Jalisco. El muestreo se realizó desde septiembre de 1993 hasta marzo de 1994 usando cuadrantes de 0.75 m2 colocados a lo largo de líneas de transectos (longitud = 10 m en réplica, en las

  7. Bivalve fouling of nuclear power plant service-water systems. Volume 2. Current status of biofouling surveillance and control techniques

    International Nuclear Information System (INIS)

    Daling, P.M.; Johnson, K.I.

    1985-03-01

    This report describes the current status of techniques for detection and control of cooling-water system fouling by bivalve mollusks at nuclear power plants. The effectiveness of these techniques is evaluated on the basis of information gathered from a literature review and in interviews with nuclear power plant personnel. Biofouling detection techniques examined in this report include regular maintenance, in-service inspection, and testing. Generally, these methods have been inadequate for detecting biofouling. Recommendations for improving biofouling detection capabilities are presented. Biofouling prevention (or control) methods that are examined in this report include intake screen systems, thermal treatment, preventive maintenance, chemical treatment alternatives, and antifoulant coatings. Recommendations for improving biofouling control methods at operating nuclear power plants are presented. Additional techniques that could be implemented at future power plants or that require further research are also described

  8. Neuro-ophthalmic manifestations of prematurity

    Directory of Open Access Journals (Sweden)

    Preeti Patil Chhablani

    2014-01-01

    Full Text Available Increasing rates of preterm births coupled with better survival of these infants have resulted in higher prevalence of systemic and ocular complications associated with prematurity. In addition to retinopathy of prematurity, infants who are born preterm may suffer from severe visual impairment as a result of hypoxic ischemic encephalopathy, hypoglycemia, and other metabolic imbalances. The effect of these processes on the anterior visual pathway may result in optic atrophy, optic nerve hypoplasia or optic disc cupping and affection of the posterior visual pathway leads to cortical visual impairment (CVI. Other ocular associations include strabismus, nystagmus, and ocular motor abnormalities such as tonic down gaze and defective saccades and pursuits. Cortical and subcortical involvement also manifests as defects in functional vision and these have not yet been completely understood. Children with CVI may have visual field defects, photophobia, defective visual processing, and deficient color vision. Since most of these children also suffer from additional systemic disabilities, evaluation, and management remains a challenge. However, early diagnosis and initiation of rehabilitation therapy can prove to be of significant benefit in these children.

  9. Antimicrobial actions of hexachlorophene: cytological manifestations.

    Science.gov (United States)

    Silvernale, J N; Joswick, H L; Corner, T R; Gerhardt, P

    1971-10-01

    Hexachlorophene is a soap-compatible bisphenol that has been widely used as an antiseptic, yet its mechanism of action is undefined. The relative threshold concentration for bactericidal effect on a susceptible test organism, Bacillus megaterium, was established to be about 10 mug/mg of cell dry weight. At this or at high (>/=100 mug/mg) concentration, adsorptive uptake by cells displayed saturation kinetics. At about 30 mug/mg, the time course of adsorption occurred in three distinct stages. The triphasic pattern was interpreted to represent successive penetration of and adsorption by the cell wall, the protoplast membrane, and the cytoplasm. This interpretation was substantiated by determinations of hexachlorophene adsorption by isolated cell components. Electron microscopy disclosed cytopathology, evidenced as gaps or discontinuities, in the protoplast membrane (but not in the cell wall or cytoplasm) at > 30 mug of hexachlorophene per mg of cell dry weight. Similarly, treatment with > 30 mug/mg allowed a fluorescigenic dye (tolyl-peri acid) to penetrate into the protoplast. However, no detectable cytological manifestations were discerned at the minimum lethal concentration of 10 mug/mg. Apparently, hexachlorophene is physically disruptive at intermediate or high relative concentrations but acts in a more subtle fashion at the minimal lethal concentration.

  10. Antimicrobial Actions of Hexachlorophene: Cytological Manifestations1

    Science.gov (United States)

    Silvernale, J. N.; Joswick, H. L.; Corner, Thomas R.; Gerhardt, Philipp

    1971-01-01

    Hexachlorophene is a soap-compatible bisphenol that has been widely used as an antiseptic, yet its mechanism of action is undefined. The relative threshold concentration for bactericidal effect on a susceptible test organism, Bacillus megaterium, was established to be about 10 μg/mg of cell dry weight. At this or at high (≥100 μg/mg) concentration, adsorptive uptake by cells displayed saturation kinetics. At about 30 μg/mg, the time course of adsorption occurred in three distinct stages. The triphasic pattern was interpreted to represent successive penetration of and adsorption by the cell wall, the protoplast membrane, and the cytoplasm. This interpretation was substantiated by determinations of hexachlorophene adsorption by isolated cell components. Electron microscopy disclosed cytopathology, evidenced as gaps or discontinuities, in the protoplast membrane (but not in the cell wall or cytoplasm) at > 30 μg of hexachlorophene per mg of cell dry weight. Similarly, treatment with > 30 μg/mg allowed a fluorescigenic dye (tolyl-peri acid) to penetrate into the protoplast. However, no detectable cytological manifestations were discerned at the minimum lethal concentration of 10 μg/mg. Apparently, hexachlorophene is physically disruptive at intermediate or high relative concentrations but acts in a more subtle fashion at the minimal lethal concentration. Images PMID:4107813

  11. Hemoglobinopathies: clinical manifestations, diagnosis, and treatment.

    Science.gov (United States)

    Kohne, Elisabeth

    2011-08-01

    Hemoglobinopathies are among the most common inherited diseases around the world. They have become much more common recently in northern and central Europe, including Germany, due to immigration. Selective review of the literature with consideration of national guidelines. The hemoglobinopathies encompass all genetic diseases of hemoglobin. They fall into two main groups: thalassemia syndromes and structural hemoglobin variants (abnormal hemoglobins). α- and β-thalassemia are the main types of thalassemia; the main structural hemoglobin variants are HbS, HbE and HbC. There are many subtypes and combined types in each group. The highly variable clinical manifestations of the hemoglobinopathies range from mild hypochromic anemia to moderate hematological disease to severe, lifelong, transfusion-dependent anemia with multiorgan involvement. Stem-cell transplantation is the preferred treatment for the severe forms of thalassemia. Supportive, rather than curative, treatment consists of periodic blood transfusions for life, combined with iron chelation. Drugs to treat the symptoms of sickle-cell disease include analgesics, antibiotics, ACE inhibitors and hydroxyurea. Blood transfusions should be given only when strictly indicated. More than 90% of patients currently survive into adulthood. Optimally treated patients have a projected life span of 50 to 60 years. Hemoglobinopathies are a public health issue in today's multiethnic German population. Adequate care of the affected patients requires a wide variety of diagnostic and therapeutic measures.

  12. Oral manifestations of AIDS: an overview.

    Science.gov (United States)

    van der Waal, I; Schulten, E A; Pindborg, J J

    1991-02-01

    Infection with the human immunodeficiency virus (HIV) may cause a variety of oral lesions, such as candidiasis, periodontal disease, hairy leukoplakia, Kaposi's sarcoma and a number of miscellaneous lesions and conditions. One hundred HIV-infected patients, including AIDS patients, referred to a University Hospital in Amsterdam, were examined orally. Most patients were initially seen by the Department of Internal Medicine, the oral examination by a well-trained dentist being part of the routine screening of all HIV-infected patients. In 80 per cent of all patients one or more HIV-related lesions of the oral mucosa was recorded. In 6 per cent of those patients the oral lesion was the first manifestation of the HIV infection. Hairy leukoplakia was observed in 15 per cent of all patients. Candidiasis proved to be the most common oral disease. In patients with full-blown AIDS the pseudomembranous form of candidiasis was the most common one, while in HIV-infected patients the erythematous type prevailed. These results emphasize the role of the dentist in making an early diagnosis of HIV infection.

  13. Oroal manifestations in patients with multiple sclerosis

    Directory of Open Access Journals (Sweden)

    Grajales González Hilda María

    2014-07-01

    Full Text Available Multiple sclerosis is a chronic autoimmune inflammatory disease of the central nervous system, characterized by the presence of acute focal inflammatory demyelination, axonal loss and gliosis. It affects predominantly in young adults between 20 and 40 years of age; it is infrequent in the pediatric age. A observational, retrospective and descriptive cohort research was conducted between May 1999 and January 2012 to assess demographic characteristics, and pathological manifestations in the oral cav- ity of children with this condition. Records of 17 patients, under 18 years of age, of either sex were included, who had been evaluated in the Department of Stomatology. Data recorded were age, sex, State of origin, oral and facial pathological features, focal cavity infections and ceod index. There were no patients with trigeminal neuralgia or facial paralysis; a 5.7% ceod index was identified. Most of the patients were under immunopressive treatment. A protocol for stomatological follow-up in patients with multiple sclerosis does not exist. The medical profession must be sensibilized to establish strategies for an integral follow-up in patients with this condition.

  14. CT manifestation of schistosoma haematobium cystitis

    International Nuclear Information System (INIS)

    Wang Yujun; Hu Lirong; Cheng Yougen; Mao Guoqun; Yang Guangzhao; Modya Camara; Mohamed Traore

    2014-01-01

    Objective: To analyze CT manifestation of Schistosoma haematobium cystitis. Methods: Retrospective analysis 32 patients, who were tested for Schistosoma haematobium cystitis using the urine filtration method. CT scan was performed for each patient with contrast enhancement. Results: The vast majority of urinary tract schistomiasis lesions were in the urinary bladder. Calcification of the bladder wall was observed in all patients and mild enhancement in non calcified zone was found after intravenous contrast. Except for 5 patients of bladder cancer, the rest were no abnormality in size of bladder when bladder was filling or emptying. Ureteral wall annular calcification could also be identified in 25 patients. Twenty two patients were companied with ureteric hydronephrosis. Seminal vesicle calcification was seen in 4 patients among 11 male patients, while both uterine and ovarian in female and prostate in men had non calcification. Serious illness can be combined with bladder cancer. In 5 patients of patients with bladder cancer, bladder showed irregular soft tissue mass which was enhanced moderately after post-contrast scan, with vesical calcification in mass medially. Conclusion: Bladder calcification is the most prominent CT feature of Schistosoma haematobium cystitis, which is useful in diagnosis the disease. (authors)

  15. DENGUE WITH ATYPICAL MANIFESTATIONS AND WHO CLASSIFICATION

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    Jayant Mahadeorao

    2015-09-01

    Full Text Available Dengue fever and dengue haemorrhagic fever are important arboviral diseases. Dengue virus belongs to family Flaviviridae , has four serotypes that spread by the bite of infected Aedes mosquitoes . Dengue epidemics can have a significant economic and health t oll. Worldwide, an estimated 3.6 billion people are at risk of infection with about 50 - 100 million new cases each year Illness produced by any of the four dengue virus serotypes varies from mild asymptomatic illness to severe fatal dengue haemorrhagic fe ver/dengue shock syndrome (DHF/DSS. During the early febrile stage clinicians cannot predict which patients will progress to severe disease. Atypical manifestations were reported are associated with high risk of mortality. The existing WHO dengue classific ation scheme and case definitions have some drawbacks. A global strategy to reduce the disease burden using integrated vector management in conjunction with early and accurate diagnosis has been advocated. Antiviral drugs and vaccines that are currently un der development could also make an important contribution to dengue control in the future

  16. [Systemic lupus erythematosus : Unusual cutaneous manifestations].

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    Stockinger, T; Richter, L; Kanzler, M; Melichart-Kotik, M; Pas, H; Derfler, K; Schmidt, E; Rappersberger, K

    2016-12-01

    Various different mucocutaneous symptoms may affect up to 80 % of systemic lupus erythematosus (SLE) patients. To investigate, various unspecific, but otherwise typical clinical symptoms of skin and mucous membranes that arise in SLE patients other than those defined as SLE criteria such as butterfly rash, chronic cutaneous lupus erythematosus, oral ulcers, and increased photosensitivity. Extensive search of peer-reviewed scientific articles was performed, medical histories of several SLE patients seen in our department were analyzed, and the rare disease courses in three SLE patients are presented. Here we present a variety of unspecific but typical mucocutaneous manifestations in SLE patients: periungual erythema, periungual telangiectasia and periungual splinter hemorrhage, papules on the dorsum of the hands, scaling erythema, sometimes associated with necrosis, especially of the ears, along with complement deficiency, and the bizarre necroses of antiphospholipid syndrome. Furthermore, we show the typical clinico-histological features of neutrophilic urticarial dermatosis, as well as those of bullous SLE and finally a severe course of bacterial sepsis with Neisseria flavescens/macacae. Here we show several unspecific but rather typical mucocutaneous symptoms in lupus patients that are indicative of SLE and thus may lead to an early diagnosis. Also, life-threatening bacterial sepsis may occur with microorganisms that are commonly considered "apathogenic", such as Neisseria flavescens/macacae, which exclusively affect immunosuppressed patients.

  17. Skin manifestations associated with kidney cancer.

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    Amin, Asim; Burgess, Earle F

    2016-06-01

    Kidney cancer is a heterogenous disease encompassing several distinct clinicopathologic entities with different underlying molecular aberrations and clinical outcomes. Renal cell carcinoma (RCC) has been shown to evoke immunologic responses that can impact the natural history of disease and clinical presentation. It is important to recognize atypical presentations of disease, including cutaneous manifestations. The incidence of skin metastases from RCC is low, yet needs to be appreciated in the appropriate setting; clinical presentation for these lesions is reviewed briefly. There are several hereditary syndromes that present with well characterized cutaneous lesions and are associated with an increased risk for RCC, including Von Hippel-Lindau and Birt-Hogg-Dubé syndromes. Given that these skin lesions may be the first presenting sign for RCC, timely recognition is of essence and both are discussed in some detail. Several therapeutic options based on immunomodulation are approved for the treatment of advanced RCC. Dermatologic toxicities observed with these agents are also briefly discussed. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Behcet's disease: epidemiology, clinical manifestations, and diagnosis.

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    Davatchi, Fereydoun; Chams-Davatchi, Cheyda; Shams, Hormoz; Shahram, Farhad; Nadji, Abdolhadi; Akhlaghi, Massoomeh; Faezi, Tahreh; Ghodsi, Zahra; Sadeghi Abdollahi, Bahar; Ashofteh, Farimah; Mohtasham, Negin; Kavosi, Hoda; Masoumi, Mariam

    2017-01-01

    Behcet's Disease (BD) is classified among vasculitides. The aim of this review was to put together different known reports in order to help the reader to better understand the disease, to avoid the frequent misdiagnosis, and to decide the best treatment. Areas covered: a) Epidemiology: BD is rare, and is seen along the Silk Road, from 20 to 420/100,000 in Turkey and 80/100,000 in Iran, to 0.64/100,000 in the UK. b) Clinical manifestations: oral aphthosis is seen in more than 95% of patients, genital aphthosis (60-90%), skin (pseudofolliculitis/erythema nodosum, 40-90%), eyes (uveitis/retinal vasculitis, 45-90%), gastrointestinal (diarrhea/hemorrhage/perforation/pain, 4-38%), vascular (venous/arterial thrombosis, aneurysm, 2.2-50%), neurological (all kinds, especially meningo-encephalitis, 2.3-38.5%), and articular (arthralgia/arthritis/ankylosing spondylitis, 11.6-93%). c) Pathergy test is positive in some patients: 8.6% (in India) to 70.7% (in China). This data was extracted from the five nationwide surveys and the largest case series from BD conference reports and a Pubmed search. Expert commentary: Diagnosis is clinical but classification/diagnosis criteria may help. The best criteria for BD is the International Criteria for Behcet's Disease (ICBD). BD is a multisystem disease progressing by attacks and remissions. Each attack may resemble the preceding or it may be different in duration, severity, and the systems involved.

  19. INNOVATION – CREATIVE MANIFESTATION WITH ECONOMIC IMPLICATIONS

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    VALENTINA MUNTEANU

    2013-05-01

    Full Text Available The present paper aims at a correct perception of innovation, regarded as a present phenomenon, for which it is necessary to resorts to a series of notions and definitions, as well as to multiple perspectives. Thus, the definition of this phenomenon - in all that it captures in it - suggests dynamism and ease of communication. The complexity of the phenomenon of innovation is the creative capacity, around which there revolve all other matters concerning innovation. The present paper also illustrates the relationship between technology and economy, meaning that technical progress makes the economic system that created it. This, in turn, provides a more consistent support for changing technology. Economic factors play a major role in the development of technology, because they are interested in reducing costs, increasing productivity, sales volume, as well as goals that can be achieved through innovation. Successful entrepreneurs in an increasingly more competitive environment try to assert through value creation rewardingly new and different outputs, a fact which represents a change from what was known at the beginning of the business. In general, innovation and to the same extent technical and technological innovation has always accompanied the development of human society. Innovation has manifesting itself throughout history with different levels of intensity. Technical-scientific revolution, present in all spheres of human activity through the accelerated mutations that produce them, fundamentally influence the way in which orientation and innovation evolve.

  20. Biochemical Manifestation of HIV Lipodystrophy Syndrome.

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    Ihenetu, Kenneth; Mason, Darius

    2012-01-01

    Highly active anti-retroviral therapy (HAART), including protease inhibitors (PI) have led to dramatic improvements in the quality and quantity of life in patients with acquired immunodeficiency syndrome (AIDS). However, a significant number of AIDS patients on HAART develop characteristic changes in body fat redistribution referred to as lipodystrophy syndrome (LDS). Features of LDS include hypertrophy in the neck fat pad (buffalo hump), increased fat in the abdominal region (protease paunch), gynecomastia and loss of fat in the mid-face and extremities. The aim of this paper is to review the current knowledge regarding this syndrome. This article reviews the published investigations on biochemical manifestation of HIV lipodystrophy syndrome. It is estimated that approximately 64% of patients treated with PI will experience this syndrome. Biochemically, these patients have increased triglycerides (Trig), total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C) and extremely low high-density lipoprotein-cholesterol (HDL-C). It is hoped that awareness of this syndrome would aid in early diagnosis and better patient management, possibly leading to a lower incidence of cardiovascular complications among these patients.