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Sample records for leech helobdella stagnalis

  1. First report of freshwater leech Helobdella stagnalis (Rhyncobdellida: Glossiphoniidae as a parasite of an anuran amphibian

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    Rocco Tiberti

    2010-12-01

    Full Text Available The authors describe the first case of parasitism on anuran amphibian, Rana temporaria, by the freshwater leech Helobdella stagnalis, in a mountainous area of northwestern Italy. The presence of skin abrasions and haemorrhages attributable to leech attack discards the hypothesis of a simple phoretic relationship between leech and frog.

  2. A new molecular logic for BMP-mediated dorsoventral patterning in the leech Helobdella.

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    Kuo, Dian-Han; Weisblat, David A

    2011-08-09

    Bone morphogenetic protein (BMP) signaling is broadly implicated in dorsoventral (DV) patterning of bilaterally symmetric animals [1-3], and its role in axial patterning apparently predates the birth of Bilateria [4-7]. In fly and vertebrate embryos, BMPs and their antagonists (primarily Sog/chordin) diffuse and interact to generate signaling gradients that pattern fields of cells [8-10]. Work in other species reveals diversity in essential facets of this ancient patterning process, however. Here, we report that BMP signaling patterns the DV axis of segmental ectoderm in the leech Helobdella, a clitellate annelid (superphylum Lophotrochozoa) featuring stereotyped developmental cell lineages, but the detailed mechanisms of DV patterning in Helobdella differ markedly from fly and vertebrates. In Helobdella, BMP2/4s are expressed broadly, rather than in dorsal territory, whereas a dorsally expressed BMP5-8 specifies dorsal fate by short-range signaling. A BMP antagonist, gremlin, is upregulated by BMP5-8 in dorsolateral, rather than ventral territory, and yet the BMP-antagonizing activity of gremlin is required for normal ventral cell fates. Gremlin promotes ventral fates without disrupting dorsal fates by selectively inhibiting BMP2/4s, not BMP5-8. Thus, DV patterning in the development of the leech revealed unexpected evolutionary plasticity of the conserved BMP patterning system, presumably reflecting its adaptation to different modes of embryogenesis. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Differential expression of conserved germ line markers and delayed segregation of male and female primordial germ cells in a hermaphrodite, the leech helobdella.

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    Cho, Sung-Jin; Vallès, Yvonne; Weisblat, David A

    2014-02-01

    In sexually reproducing animals, primordial germ cells (PGCs) are often set aside early in embryogenesis, a strategy that minimizes the risk of genomic damage associated with replication and mitosis during the cell cycle. Here, we have used germ line markers (piwi, vasa, and nanos) and microinjected cell lineage tracers to show that PGC specification in the leech genus Helobdella follows a different scenario: in this hermaphrodite, the male and female PGCs segregate from somatic lineages only after more than 20 rounds of zygotic mitosis; the male and female PGCs share the same (mesodermal) cell lineage for 19 rounds of zygotic mitosis. Moreover, while all three markers are expressed in both male and female reproductive tissues of the adult, they are expressed differentially between the male and female PGCs of the developing embryo: piwi and vasa are expressed preferentially in female PGCs at a time when nanos is expressed preferentially in male PGCs. A priori, the delayed segregation of male and female PGCs from somatic tissues and from one another increases the probability of mutations affecting both male and female PGCs of a given individual. We speculate that this suite of features, combined with a capacity for self-fertilization, may contribute to the dramatically rearranged genome of Helobdella robusta relative to other animals.

  4. Isolation, characterization, and expression of Le-msx, a maternally expressed member of the msx gene family from the glossiphoniid leech, Helobdella.

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    Master, V A; Kourakis, M J; Martindale, M Q

    1996-12-01

    The msx gene family is one of the most highly conserved of the nonclustered homeobox-containing genes. We have isolated an msx homolog (Le-msx) from the glossiphoniid leech, Helobdella robusta, and characterized its pattern of expression by whole mount in situ hybridization. In situ expression and reverse transcription polymerase chain reaction (RT-PCR) data results show that Le-msx is a maternal transcript initially uniformly distributed in the cortex of immature oocytes that becomes asymmetrically localized to the polar regions of the uncleaved zygote. This is the earliest reported expression for the msx gene family and the first maternally expressed homeodomain-containing transcription factor reported in annelids. During embryonic development, Le-msx is expressed in all 10 embryonic stem cells and their segmental founder cell descendants. At midembryonic stages, Le-msx is expressed in the expanding germinal plate. Le-msx is confined to the central nervous system and nephridia at late (stage 9) stages and subsequently disappears from nephridia. In addition, we present a phylogenetic hypothesis for the evolution of the msx gene family, including the identification of a putative C. elegans msx homolog and the realignment of the sponge msx homolog to the NK class of homeodomain genes.

  5. A new leech species of Helobdella (Hirudinea, Glossiphoniidae from San Carlos de Bariloche, Río Negro, Argentina Una especie nueva de sanguijuela del género Helobdella (Hirudinea, Glossiphoniidae de San Carlos de Bariloche, Río Negro, Argentina

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    Bettina S. Gullo

    2009-04-01

    Full Text Available A new freshwater leech species Helobdella fantasmae n. sp. is described. This description is based on the examination of 12 specimens collected in Laguna Fantasma, Bariloche (41° 05'S 71° 28'W, during December 2002. Leeches were found attached to submerged plants. They were relaxed with gradual addition of 70% ethanol, fixed in 10% formalin, stored in 70% ethanol and stained with borax carmine. Examination of external morphology, dissections and microphotographs were accomplished with a Leica Wild M3Z stereo microscope aided with an Olympus C-4000 digital camera. H. fantasmae n. sp. differs from other species of the genus by the presence of 1 pair of eyes on somite III, crop without gastric chambers, digitiform caeca and postcaeca., short sperm ducts reaching the back of somite XV, atrium pyriform, short ovisacs reaching somite XIII. This is the first record of leeches from an ephemeral wetland in North Patagonia. This finding expands current knowledge of the biodiversity of Hirudinea in South America, increasing the number of known Helobdella spp. from the Río Negro province (North Patagonia to 10 species.Se describe una especie de sanguijuela dulceacuícola Helobdella fantasmae n. sp. Esta descripción se basa en el examen de 12 ejemplares recolectados en la Laguna Fantasma, Bariloche (41° 05'S 71° 28'O durante diciembre de 2002. Los individuos se hallaron asociados a la vegetación sumergida. Fueron relajados con la adición gradual de etanol 70%, fijados en formalina al 10%, preservados en etanol 70% y teñidos con carmín borácico. El examen de la morfología externa, disecciones y microfotografías fueron realizados con la ayuda de un estereomicroscopio Leica Wild M3Z con cámara digital Olympus C-4000. H. fantasmae n. sp. difiere de otras especies del género por los siguientes caracteres: un par de ojos en el somito III, estómago recto sin cámaras, ciegos laterales ni postciegos, espermiductos cortos que descienden hasta el

  6. Medical leech therapy (Hirudotherapy

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    Uwe Wollina

    2016-01-01

    Full Text Available Leeches have been used in medicine long time before BC. In recent years medical leech therapy has gained increasing interest in reconstructive surgery and pain management and other medical fields. The possible indications and success rates of this treatment are discussed. There is a special interest in salvage of flaps and grafts by the use of medical leeches. Retrospective analysis indicates a success rate of >80%. Randomized controlled trials have been performed in osteoarthritis. Case reports and smaller series are available for the treatment of chronic wounds, post-phlebitic syndrome and inflammatory skin diseases. The most common adverse effects are prolonged bleeding and infection by saprophytic intestinal bacteria of leeches. Medical leech therapy is a useful adjunct to other measures wound management.

  7. When Leeches reveal Biodiversity

    DEFF Research Database (Denmark)

    Schnell, Ida Bærholm

    to provide information about vertebrate biodiversity. This thesis covers the development of a monitoring method based on iDNA extracted from terrestrial haematophagous leeches, a continuation of the work presented in Schnell et al., 2012. The chapters investigate and/or discuss different subjects regarding...

  8. Ocular leech infestation

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    Lee YC

    2015-02-01

    Full Text Available Yueh-Chang Lee, Cheng-Jen Chiu Department of Ophthalmology, Buddhist Tzu-Chi General Hospital, Hualien, Taiwan, ROC Abstract: This case report describes a female toddler with manifestations of ocular leech infestation. A 2-year-old girl was brought to our outpatient clinic with a complaint of irritable crying after being taken to a stream in Hualien 1 day previous, where she played in the water. The parents noticed that she rubbed her right eye a lot. Upon examination, the girl had good fix and follow in either eye. Slit-lamp examination showed conjunctival injection with a moving dark black–brown foreign body partly attached in the lower conjunctiva. After applying topical anesthetics, the leech, measuring 1 cm in length, was extracted under a microscope. The patient began using topical antibiotic and corticosteroid agents. By 1 week after extraction, the patient had no obvious symptoms or signs, except for a limited subconjunctival hemorrhage, and no corneal/scleral involvement was observed. Keywords: leech, ocular foreign body, conjunctival reaction, pediatric ophthalmology

  9. Ciprofloxacin-Resistant Aeromonas hydrophila Cellulitis following Leech Therapy

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    Giltner, Carmen L.; Bobenchik, April M.; Uslan, Daniel Z.; Deville, Jaime G.

    2013-01-01

    We report a case of surgical site infection with ciprofloxacin-resistant Aeromonas hydrophila following leech therapy. Antimicrobial and genetic analyses of leech and patient isolates demonstrated that the resistant isolates originated from the leech gut microbiota. These data suggest that ciprofloxacin monotherapy as a prophylaxis regimen prior to leech therapy may not be effective in preventing infection. PMID:23363826

  10. Internal contamination with leech in a turkey

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    Mahmoud Bahmani

    2015-02-01

    Full Text Available Leech enters to mouth and nose through water. Nose and nasopharynx mucosa are the most preferred places for leech attachment with epistaxis and respiratory distress symptoms. But the leeches may rarely stick deeper to trachea or esophagus which could cause hematemesis, hemoptysis and severe respiratory distress. Leech infestation can cause gastrointestinal, respiratory and genital bleeding in rare cases. Various animals such as ruminants, single-toed and carnivores, are easily infected with leeches. In May 2014, a 2-year-old turkey infected with leeches through the contaminated drinking water was referred to a veterinarian with respiratory distress symptoms, anxiety, bleeding from the mouth in Maze-Abdali Village located at 17 km from Dehloran City of Ilam Province in the west of Iran. After physical observations, a moving dark green particle was seen. Limnatis nilotica were detected after separation from the oral cavity of turkey. Respiratory distress and oral cavity bleeding should be regarded in the areas where spring and flooded water were infested with leeches. Untreated and contaminated waters consumption should be prohibited.

  11. Leeches as a source of mammalian viral DNA and RNA - a study in medicinal leeches

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    Kampmann, Marie-Louise; Schnell, Ida Bærholm; Jensen, Randi Holm

    2017-01-01

    V]) from nucleic acids extracted from medicinal leeches fed with blood spiked with each virus. All viruses except BHV showed a gradual decline in concentration from day 1 to 50, and all except BHV were detectable in at least half of the samples even after 50 days. BHV exhibited a rapid decline at day 27...... and was undetectable at day 50. Our findings in medicinal leeches indicate that leeches collected in the wild might be an untapped resource for detecting vertebrate viruses and could provide new opportunities to study wildlife viral diseases of rare species in challenging environments, where capturing and handling...

  12. An overview of leech and its therapeutic applications

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    Parimannan Sivachandran

    2015-05-01

    Full Text Available Hirudotherapy has a broad spectrum of therapeutic application in the medical field ranging from cardiology, gynaecology, ophthalmology, plastic and reconstructive surgeries. In medieval and early modern medicine, leeches were used to remove blood from patients in an attempt to balance the biological humours. Leeches are widely used to treat venous congestion in microvascular replantation, free and conventional flap surgery and traumatology. Recently, Food and Drug Administration has approved the usage of live leeches as medical device for therapeutic applications. Presently, some of the leech species have declined dramatically in its population due to the over utilization of leech for medicinal purposes and also due to pollution in several parts of the world particularly in European and Asian countries. This review presents an overview of leech including the history, biology, classification, and its application as medical device. Further, it also covers the controversies and misconception related to leech species identification and complications of post hirudotherapy.

  13. The literature review of Leech therapy

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    Jang Hyo-kil

    2010-03-01

    Full Text Available Objective : To review the trend of the study related to Leech therapy and to establish the hereafter direction for the study on Leech therapy. Methods : I reviewed and analyzed all the theses published in Domestic and Foreign research institution from 1990 to 2009. Results : The following results were obtained in this study. 1. Analyzed number of theses published, there was no significance per year. 2. Classified by theme of journal, journals related to surgery were most(41 journals, 75.92% among 54 kinds. 3. Classified by theses by research method and thesis types, case report accounted for nearly twothirds (52 pieces, 68.42% of all theses and consideration of document was next(9 pieces, 11.84%. 4. With the most case of venous congestion after plastic and reconstructive surgery(33 pieces, 63.46%, leech therapy was effective on illnesses such as haematoma, macroglossia, purpura, varicous vein, avulsion injury, neurovascular compression, diabetic neuropathy, penoscrotal oedema, buerger's disease, rheumatoid arthritis. 5. Two most appeared adverse effects were anemia and infection. Immediate blood transfusion was done for recovering anemia and prophylactic 3rd generation antibiotics to infection were emphasized in more than half of case reports. 6. All of consideration of documents was retrospective study of cases related leech therapy and 3 pieces of them emphasized prophyratic antibiotic treatment for preventing infection. 7. The study of clinical trail type started first in 2002 and osteoarthritis of knee and carpometacarpal joint were main target. As see above result, Leech therapy was effective cure and could be used in disease induced by venous congestion. And I think that it is necessary to perform additional study related to solution of problems about leech therapy and protocol for using in clinical practice.

  14. Leech in urinary bladder causing hematuria.

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    Alam, Shadrul; Das Choudhary, Mrigen Kumar; Islam, Kabirul

    2008-02-01

    To estimate efficacy of normal saline in the management of hematuria caused by accidental entry of a leech per urethra into the urinary bladder. An intervention study was carried out in the Department of Pediatric Surgery of Sylhet MAG Osmani Medical College between January 1998 and December 2003. A total of 43 boys (mean age 8 years, SD+/-2.6) were enrolled. In all cases, a leech had entered the urinary bladder through the urethra causing hematuria. All patients were equipped with a self-retaining Foley catheter. They were managed by infusing 50ml of normal saline into the urinary bladder through the catheter that was then clamped for 3h. After removing the catheter, in all cases the whole leech was spontaneously expelled intact, dead or alive, within 2-24h during the subsequent act of micturition. Hematuria gradually diminished to a clear flow within the next 6h in 27 cases, 12h in 14 cases and 24h in two cases. All patients were followed up for 2 weeks, and none developed recurrent hematuria. Catheterization and irrigation of the urinary bladder with normal saline is a relatively simple, safe and inexpensive method of removing the leech and controlling hematuria.

  15. Construction of a medicinal leech transcriptome database and its application to the identification of leech homologs of neural and innate immune genes

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    Wincker Patrick

    2010-06-01

    evolutionarily conserved sequences, representing all known pathways involved in these important functions. Conclusions The sequences obtained for Hirudo transcripts represent the first major database of genes expressed in this important model system. Comparison of translated open reading frames (ORFs with the other openly available leech datasets, the genome and transcriptome of Helobdella robusta, shows an average identity at the amino acid level of 58% in matched sequences. Interestingly, comparison with other available Lophotrochozoans shows similar high levels of amino acid identity, where sequences match, for example, 64% with Capitella capitata (a polychaete and 56% with Aplysia californica (a mollusk, as well as 58% with Schistosoma mansoni (a platyhelminth. Phylogenetic comparisons of putative Hirudo innate immune response genes present within the Hirudo transcriptome database herein described show a strong resemblance to the corresponding mammalian genes, indicating that this important physiological response may have older origins than what has been previously proposed.

  16. Construction of a medicinal leech transcriptome database and its application to the identification of leech homologs of neural and innate immune genes.

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    Macagno, Eduardo R; Gaasterland, Terry; Edsall, Lee; Bafna, Vineet; Soares, Marcelo B; Scheetz, Todd; Casavant, Thomas; Da Silva, Corinne; Wincker, Patrick; Tasiemski, Aurélie; Salzet, Michel

    2010-06-25

    , representing all known pathways involved in these important functions. The sequences obtained for Hirudo transcripts represent the first major database of genes expressed in this important model system. Comparison of translated open reading frames (ORFs) with the other openly available leech datasets, the genome and transcriptome of Helobdella robusta, shows an average identity at the amino acid level of 58% in matched sequences. Interestingly, comparison with other available Lophotrochozoans shows similar high levels of amino acid identity, where sequences match, for example, 64% with Capitella capitata (a polychaete) and 56% with Aplysia californica (a mollusk), as well as 58% with Schistosoma mansoni (a platyhelminth). Phylogenetic comparisons of putative Hirudo innate immune response genes present within the Hirudo transcriptome database herein described show a strong resemblance to the corresponding mammalian genes, indicating that this important physiological response may have older origins than what has been previously proposed.

  17. Medicinal leech therapy-an overall perspective.

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    Sig, Ali K; Guney, Mustafa; Uskudar Guclu, Aylin; Ozmen, Erkan

    2017-12-01

    Complementary medicine methods have a long history, but modern medicine has just recently focused on their possible modes of action. Medicinal leech therapy (MLT) or hirudotherapy, an old technique, has been studied by many researchers for possible effects on various diseases such as inflammatory diseases, osteoarthritis, and after different surgeries. Hirudo medicinalis has widest therapeutic usage among the leeches, but worldwide, many different species were tested and studied. Leeches secrete more than 20 identified bioactive substances such as antistasin, eglins, guamerin, hirudin, saratin, bdellins, complement, and carboxypeptidase inhibitors. They have analgesic, anti-inflammatory, platelet inhibitory, anticoagulant, and thrombin regulatory functions, as well as extracellular matrix degradative and antimicrobial effects, but with further studies, the spectrum of effects may widen. The technique is cheap, effective, easy to apply, and its modes of action have been elucidated for certain diseases. In conclusion, for treatment of some diseases, MLT is not an alternative, but is a complementary and/or integrative choice. MLT is a part of multidisciplinary treatments, and secretes various bioactive substances. These substances vary among species and different species should be evaluated for both treatment capability and their particular secreted molecules. There is huge potential for novel substances and these could be future therapeutics.

  18. External auditory canal leech: a rare case report of paediatric ...

    African Journals Online (AJOL)

    Leeches are blood sucking organism feed on human blood. While human bites are common, they rarely cause human internal infestation. We describe a rare case of a parasitic leech infestation of the External Auditory Canal (EAC). A two month old child presented to the Emergency department with a seven day history of ...

  19. Hunting leeches in the dense forests of Madagascar

    DEFF Research Database (Denmark)

    Bohmann, Kristine

    2013-01-01

    Identifying DNA from prey blood stored inside leeches reveals which animals the leeches have preyed on. This can be used to monitor wildlife. To find out whether this new wildlife screening method might be able to aid conservation efforts in Madagascar, the Centre for GeoGenetics has undertaken...

  20. MARINE LEECH ANTICOAGULANT DIVERSITY AND EVOLUTION.

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    Tessler, Michael; Marancik, David; Champagne, Donald; Dove, Alistair; Camus, Alvin; Siddall, Mark E; Kvist, Sebastian

    2018-03-16

    Leeches (Annelida: Hirudinea) possess powerful salivary anticoagulants and, accordingly, are frequently employed in modern, authoritative medicine. Members of the almost exclusively marine family Piscicolidae account for 20% of leech species diversity, and feed on host groups (e.g., sharks) not encountered by their freshwater and terrestrial counterparts. Moreover, some species of Ozobranchidae feed on endangered marine turtles and have been implicated as potential vectors for the tumor-associated turtle herpesvirus. In spite of their ecological importance and unique host associations, there is a distinct paucity of data regarding the salivary transcriptomes of either of these families. Using next generation sequencing, we profiled transcribed, putative anticoagulants and other salivary bioactive compounds that have previously been linked to bloodfeeding from 7 piscicolid species (3 elasmobranch-feeders; 4 non-cartilaginous fish-feeders) and 1 ozobranchid species (2 samples). In total, 149 putative anticoagulants and bioactive loci were discovered in varying constellations throughout the different samples. The putative anticoagulants showed a broad spectrum of described antagonistic pathways, such as inhibition of factor Xa and platelet aggregation, that likely have similar bioactive roles in marine fish and turtles. A transcript with homology to ohanin, originally isolated from king cobras, was found in Cystobranchus vividus but is otherwise unknown from leeches. Estimation of selection pressures for the putative anticoagulants recovered evidence for both positive and purifying selection along several isolated branches in the gene trees and positive selection was also estimated for a few select codons in a variety of marine species. Similarly, phylogenetic analyses of the amino acid sequences for several anticoagulants indicated divergent evolution.

  1. Respiratory adaptations to oxygen lack in three species of Glossiphoniidae (Hirudinea) in Lake Esrom, Denmark

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    Pohle, B. D.; Hamburger, K.

    2005-01-01

    The weight-specific respiration rate (µl O2 mg-1 AFDW h-1) of three species of leech from Lake Esrom, Denmark, Glossiphonia concolor, G. complanata and Helobdella stagnalis was measured in a closed stirred chamber with a micro electrode. At declining oxygen concentration (mg O2 l-1) all three spe...... at 10 and 20 °C, respectively. The results were discussed in relation to habitat and spatial distribution of the three species in the lake....

  2. Alternative leech vectors for frog and turtle trypanosomes.

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    Siddall, M E; Desser, S S

    1992-06-01

    Trypanosoma pipientis infections were achieved by exposing laboratory-raised bullfrog tadpoles (Rana catesbeiana) to the leech Desserobdella picta that had fed on infected frogs. Likewise, a laboratory-raised snapping turtle (Chelydra serpentina) was infected with Trypanosoma chrysemydis following exposure to infected Placobdella ornata. Transmission of the trypanosomes by these leeches constitutes new vector records for the parasites. The biology of D. picta and P. ornata suggests that they are more important in transmitting these flagellates than the species of leech previously reported as vectors.

  3. Prolonged bleeding on the neck in leech therapy: Case report

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    Atakan Savrun

    2015-12-01

    Full Text Available Superficial skin bleeding can usually be stopped by applying short-time compression, unless the patient suffers from coagulation disorders or uses anticoagulant. Because of the anticoagulant component of leech saliva, a leech bite may cause long-time bleeding, which cannot be stopped via compression. In this study, the case of a patient who applied leech therapy on her neck for the treatment of migraine has been presented. [Arch Clin Exp Surg 2015; 4(4.000: 234-237

  4. effect of physico-chemical parameters of water containing leech

    African Journals Online (AJOL)

    PROF EKWUEME

    analysis. Prior to the collection of the water, the temperature, pH conductivity were measured in situ, using the appropriate .... temperate climates were the ecological factors support ... leeches show endogenous rhythm of activity controlled.

  5. Clinical efficacy of Jalaukawacharana (leech application) in Thrombosed piles.

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    Bhagat, Pradnya J; Raut, Subhash Y; Lakhapati, Arun M

    2012-04-01

    'Arsha' (hemorrhoids) is an ailment that affects all economical groups of population. Though the disease is within the limits of management, it has its own complications like severe hemorrhage, inflammation, and thrombosis, by which a patient gets severe pain and is unable to continue his routine work. Prior to surgical treatment of hemorrhoids, associated conditions like inflammation, strangulation, thrombosis, etc. need to be managed. Thrombosed piles possibly occur due to high venous pressure associated with severe anal pain. Leech (Hirudina medicanalis) application is found to be effective in reducing pain. In thrombosed piles, leech application has shown thrombolytic action, which contributes in re-establishment of circulation. It is observed in the study that, pus and mucous discharge have been reduced after leech application; which may be due to antimicrobial and mucolytic properties of leech. This method of treatment is found to be effective and increase the quality of life in patients suffering with thrombosed piles.

  6. Chemosensitivity of the osphradium of the pond snail Lymnaea stagnalis

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    Wedemeyer; Schild

    1995-01-01

    The osphradium of the pond snail Lymnaea stagnalis was studied to determine the stimuli to which this organ responds. The following stimuli were tested: hypoxia, hypercapnia, a mixture of amino acids, a mixture of citralva and amyl acetate and a mixture of lyral, lilial and ethylvanillin. The mean nerve activity consistently increased with elevated PCO2, whereas hypoxia produced variable effects. The nerve activity became rhythmic upon application of citralva and amyl acetate, but it increased in a non-rhythmic way upon application of the other two odorant mixtures tested. Whole-cell patch-clamp recordings were made from a group of 15 neurones that lay next to the issuing osphradial nerve, to determine whether ganglion cells were involved in olfactory signal processing. All neurones tested responded to at least one of the three mixtures of odorants. Both excitatory and inhibitory responses occurred. Our results indicate that the osphradium of the pond snail Lymnaea stagnalis is sensitive to elevated PCO2 as well as to three different classes of odorants. In addition, at least some neurones within the osphradium are involved in the processing of olfactory information.

  7. A clinical trial for evaluation of leech application in the management of Vicarcikā (Eczema

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    K M Pratap Shankar

    2014-01-01

    Conclusion : Leech application gives significant relief for the symptoms of eczema. The life quality of the patient also improved significantly after leech therapy. No adverse reactions were reported during the entire course of study.

  8. Anti-leech activity of Scutellaria baicalensis and Morinda citrifolia extracts against Piscicola geometra

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    Rizky, P. N.; Cheng, T. C.; Nursyam, H.

    2018-04-01

    Piscicola geometra leeches are naturally infecting cobia juvenile. The leeches attach to cobia by sucking and biting its surface and provide the gate of second infection. Water extracts of Scutellaria baicalensis root and Morinda citrifolia leaves were used to be tested through In Vitro method to look for the anti-leeches activity against Piscicola geometra. In this study, a total number of 800 leeches from infected cobia were prepared. The anti-leech activity from water extract of S. baicalensis root and M. citrifolia leaves were compared in different dilutions of plant extracts for 96 hours. Significant anti-leech activity was observed with M. citrifolia leaves with 80% mortality of leeches. S. baicalensis root showed higher anti-leech activity with 100% mortality of leeches. The average time was needed for S.baicalensis root to paralyzing and kill the leeches were 8h, 40h, 48h, 72h, and 96h in various dilutions of S. baicalensis root. This study indicated that S. baicalensis water extract had a potent for new anti-leeches agent.

  9. Clinical uses of the medicinal leech: A practical review

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    B S Porshinsky

    2011-01-01

    Full Text Available The medicinal leech, Hirudo medicinalis, is an excellent example of the use of invertebrates in the treatment of human disease. Utilized for various medical indications since the ancient times, the medicinal leech is currently being used in a narrow range of well-defined and scientifically-grounded clinical applications. Hirudotherapy is most commonly used in the setting of venous congestion associated with soft tissue replantations and free flap-based reconstructive surgery. This is a comprehensive review of current clinical applications of hirudotherapy, featuring a comprehensive search of all major medical search engines (i.e. PubMed, Google Scholar, ScientificCommons and other cross-referenced sources. The authors focus on indications, contraindications, practical application/handling of the leech, and therapy-related complications.

  10. Bronchial Leech Infestation in a 15-Year-Old Female.

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    Moslehi, Mohammad Ashkan; Imanieh, Mohammad Hadi; Adib, Ali

    2016-01-01

    Foreign body aspiration (FBA) is a common incidence in young children. Leeches are rarely reported as FBA at any age. This study describes a 15-year-old female who presented with hemoptysis, hematemesis, coughs, melena, and anemia seven months prior to admission. Chest X-ray showed a round hyperdensity in the right lower lobe. A chest computed tomography (CT) demonstrated an area of consolidation and surrounding ground glass opacities in the right lower lobe. Hematological investigations revealed anemia. Finally, bronchoscopy was performed and a 5 cm leech was found within the right B 7-8 bronchus and removed by forceps and a Dormia basket.

  11. Some Biological Activities of Malaysian Leech Saliva Extract

    OpenAIRE

    Abdualrahman M. Abdualkader; Ahmed Merzouk; Abbas Mohammed Ghawi; and Mohammed Alaama

    2011-01-01

    Leeches were fed on the phagostimulatory solution through parafilm membrane. The satiated leeches were forced to regurgitate the solution by soaking them in an ice-container. The anticoagulant activity was ascertained using thrombin time assay (TT). The result revealed that the saliva concentration which increases TT by 100% (IC100) is 43.205µg/ml plasma. The antimicrobial activity of the saliva was tested against several bacterial spp. (E.coli, P.aeruginosa, B.cereus, Sal.typhi and S...

  12. Use of the mechanical leech for successful zone I replantation.

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    Kim, Sang Wha; Han, Hyun Ho; Jung, Sung-No

    2014-01-01

    Replantation of zone I finger injuries remains a challenge, particularly if the fingertip was previously scarred or atrophied, which makes it difficult to secure a suitable vein at the amputation site. In cases of artery-only anastomosis, we propose using a mechanical leech technique to maintain sufficient venous outflow until the internal circulation regenerates. We applied this procedure to eight patients who had zone 1 amputations without veins that were suitable for anastomosis. Emergent surgery was performed and an artery-only anastomosis was created. As there were no veins available, we cut a branch of the central artery and anastomosed it with a 24-gauge angioneedle, which served as a conduit for venous drainage. The overall survival rate for zone I replantation using mechanical leech was 87.5% and the average time to maintain the mechanical leech was 5 days. The mechanical leech technique may serve as an alternative option for the management of venous congestion when no viable veins are available.

  13. Use of the Mechanical Leech for Successful Zone I Replantation

    Directory of Open Access Journals (Sweden)

    Sang Wha Kim

    2014-01-01

    Full Text Available Replantation of zone I finger injuries remains a challenge, particularly if the fingertip was previously scarred or atrophied, which makes it difficult to secure a suitable vein at the amputation site. In cases of artery-only anastomosis, we propose using a mechanical leech technique to maintain sufficient venous outflow until the internal circulation regenerates. We applied this procedure to eight patients who had zone 1 amputations without veins that were suitable for anastomosis. Emergent surgery was performed and an artery-only anastomosis was created. As there were no veins available, we cut a branch of the central artery and anastomosed it with a 24-gauge angioneedle, which served as a conduit for venous drainage. The overall survival rate for zone I replantation using mechanical leech was 87.5% and the average time to maintain the mechanical leech was 5 days. The mechanical leech technique may serve as an alternative option for the management of venous congestion when no viable veins are available.

  14. Control of aquatic leeches (Lymnatis nilotica) us- ing Phytolacca ...

    African Journals Online (AJOL)

    also caused mortality of tadpoles, frogs and round worms found in streams while it doesn't cause any visible toxicity to .... immature age died of leech infestation. About 50 calves that were watered at .... vary depending on the type of water medium (Getachew Tilahun et al., 2002) and in cases where higher doses are ...

  15. Isolation and Analytical Characterization of Local Malaysian Leech Saliva

    Directory of Open Access Journals (Sweden)

    Mohamed Alaama

    2011-12-01

    Full Text Available Leech saliva contains biologically active compounds that are mainly proteins and peptides. In this study a modified and smooth extraction method of saliva was used without leeches' scarification. UV and Bradford Assay protein methods showed that the saliva extract contains high concentrations of proteins. RP-HPLC chromatogram revealed that more than 30 different peaks were observed in leech saliva extract. Gel electrophoresis revealed the existence of proteins and peptides with different molecular weights. The gel showed up to 25 different bands. Comparison of gel electrophoresis data with protein database revealed the closeness of four molecular weights to known proteins from Hirudinaria leech family. Other proteins detected by gel electrophoresis may be related to completely new biologically active proteins and peptides in the saliva extract or to a modification (isoforms of the existing ones or finally to a mixture of both.ABSTRAK: Air liur pacat secara biologinya mengandungi sebahagian besar campuran aktif protein dan peptida. Dalam kajian ini, kaedah pengestrakan air liur pacat yang telah diubah suai digunakan tanpa perlu membunuh pacat. Kaedah protein Cerakin UV dan Bradford menunjukkan air liur pacat yang diekstrak mengandungi konsentrasi protein yang tinggi. Kromatogram RP-HPLC memperlihatkan lebih daripada 30 puncak berbeza diperolehi semasa air liur pacat diekstrak. Gel elektroforesis memperlihatkan kewujudan protein dan peptida dengan berat molekul yang berbeza. Gel menunjukkan hingga 25 jalur yang berbeza. Perbandingan data menggunakan gel elektroforesis seiring dengan pangkalan data protein memperlihatkan persamaan empat berat molekul, dengan protein yang yang dikenali daripada keluarga pacat Hirudinaria. Jenis protein lain yang dikesan dengan menggunakan gel elektrofosis mungkin juga berkait secara biologinya dengan protein dan peptida aktif yang baru, dalam ekstrak air liur atau pengubahsuaian (beberapa jenis yang berbeza daripada

  16. Leech management before application on patient: a nationwide survey of practices in French university hospitals

    Directory of Open Access Journals (Sweden)

    Delphine Grau

    2018-02-01

    Full Text Available Abstract Background Leech therapy in plastic/reconstructive microsurgery significantly improves a successful outcome of flap salvage but the drawback is a risk of severe infection that results in a drop of the salvage rates from 70-80% to below 30%. We report the results of a national survey conducted in all the French university hospitals to assess the current extent of use of leech for medical practices in the hospital and to investigate maintenance, delivery practices and prevention of the risk of infection. Methods Data concerning conditions of storage, leech external decontamination, microbiological controls, mode of delivery and antibiotic prophylaxis were collected from all the French university hospitals in practicing leech therapy, on the basis of a standardized questionnaire. Results Twenty-eight of the 32 centers contacted filled the questionnaire, among which 23 practiced leech therapy, mostly with a centralized storage in the pharmacy; 39.1% of the centers declared to perform leech external decontamination and only 2 centers recurrent microbiological controls of the water storage. Leech delivery was mostly nominally performed (56.5%, but traceability of the leech batch number was achieved in only 39.1% of the cases. Only 5 centers declared that a protocol of antibiotic prophylaxis was systematically administered during leech therapy: either quinolone (2, sulfamethoxazole/trimethoprim (2 or amoxicillin/clavulanic acid (1. Conclusions Measures to prevent infectious complications before application to patient have to be better applied and guidelines of good practices are necessary.

  17. Peptidergic modulation of male sexual behavior in Lymnaea stagnalis: structural and functional characterization of -FVamide neuropeptides

    NARCIS (Netherlands)

    Smit, A.B.; van Kesteren, R.E.; van Minnen, J.; van Golen, F.A.; Jimenez, C.R.; Li, K.W.

    2003-01-01

    In the simultaneous hermaphrodite snail Lymnaea stagnalis, copulation as a male is controlled by neurons that send axons to the male copulatory organs via a single penis nerve. Using direct mass spectrometry of a penis nerve sample, we show that one of the molecular ions has a mass corresponding to

  18. An improved anti-leech mechanism based on session identifier

    Science.gov (United States)

    Zhang, Jianbiao; Zhu, Tong; Zhang, Han; Lin, Li

    2012-01-01

    With the rapid development of information technology and extensive requirement of network resource sharing, plenty of resource hotlinking phenomenons appear on the internet. The hotlinking problem not only harms the interests of legal websites but also leads to a great affection to fair internet environment. The anti-leech technique based on session identifier is highly secure, but the transmission of session identifier in plaintext form causes some security flaws. In this paper, a proxy hotlinking technique based on session identifier is introduced firstly to illustrate these security flaws; next, this paper proposes an improved anti-leech mechanism based on session identifier, the mechanism takes the random factor as the core and detects hotlinking request using a map table that contains random factor, user's information and time stamp; at last the paper analyzes the security of mechanism in theory. The result reveals that the improved mechanism has the merits of simple realization, high security and great flexibility.

  19. Leeches as Sensor-bioindicators of River Contamination by PCBs

    Directory of Open Access Journals (Sweden)

    Gorzyslaw Poleszczuk

    2009-03-01

    Full Text Available The aim of the study was to evaluate the use of leeches of the genus Erpobdella as a means of assessing polychlorinated biphenyl contamination of watercourses. The River Skalice, heavily contaminated with PCBs, was selected as a model. The source of contamination was a road gravel processing factory in Rožmitál pod Třemšínem from which an estimated 1 metric ton of PCBs leaked in 1986. Levels of PCB were measured in leeches collected between 1992 to 2003 from 11 sites covering about 50 km of the river (the first sampling site upstream to the source of contamination and 10 sites downstream. The PCB indicator congeners IUPA no. 28, 52, 101, 118, 138, 153, and 180 were measured. Levels were highest at the four sampling sites nearest the source of pollution. The highest values of PCB congeners were found in 1992. PCB content decreased from 1992 to 2003 and with distance from the source. The study indicated that leeches of the genus Erpobdella are a suitable bioindicator of contamination in the surface layer of river sediments.

  20. Baseline growth and reproductive parameters in Lymnaea stagnalis for OECD test guideline development: optimization of diets and culturing conditions

    DEFF Research Database (Denmark)

    Holbech, Henrik; Hutchinson, Tom

    laboratories in Denmark, Germany and the UK for the OECD pre-validation work to date. Laboratory cultures of L. stagnalis are traditionally fed fresh (preferably organic) lettuce; however, interrupted supplies of fresh lettuce in some countries in 2011 highlighted a potential problem for the draft OECD test...... of a mollusc reproduction test guideline. An ad hoc mollusc expert group has been formed in Europe to validate methods that can meet this need. Currently, a key species for use in this context is the freshwater gastropod Lymnaea stagnalis. An important aspect of this work is to first develop a specific...... pathogen free defined strain of L. stagnalis and second to establish a historical database of growth and reproductive rates under defined culturing conditions. A mass culture of the RENILYS® strain of L. stagnalis have been established at INRA (France) since 2002 and has been distributed to research...

  1. An Array of Opportunities: Building a Sustainable Future at Leech Lake Tribal College

    Science.gov (United States)

    Buckland, Hannah

    2018-01-01

    With support from Leech Lake Tribal College (LLTC) in Cass Lake, Minnesota, solar energy infrastructure--as well as specialized training and well-paying jobs--are coming to the Leech Lake Nation. Rather than power LLTC's facilities, a 40- kilowatt solar garden installed on the college's campus during the 2017 fall semester, along with four similar…

  2. Occurrence of three leech species (Annelida: Hirudinida) on fishes in the Kentucky River

    Science.gov (United States)

    Leeches were collected from six fish species distributed among four of ten sites sampled. The leech species observed were Myzobdella reducta (Meyer, 1940) and Myzobdella lugubris Leidy, 1851 of the family Piscicolidae and Placobdella pediculata Hemingway, 1908 of the family Gloss...

  3. Chemical speciation and bioavailability of transuranics for a freshwater snail (Lymnaea stagnalis L.)

    International Nuclear Information System (INIS)

    Thiels, G.M.; Murray, C.N.; Rade, J.

    1981-01-01

    It is now becoming clear that the determination of the physico-chemical forms of transuranic elements is an important step in assessing their behaviour at very low environmental levels. Data from both simulated environmental systems as well as in-situ investigations have shown the necessity of understanding the source term of contamination, which probably plays a major role in the long-term distribution of these elements. In the present paper an experimental procedure is outlined, which allows a more extensive investigation into some aspects of the biogeochemical behaviour of two transuranics: 237 Pu and 241 Am. Two chemical methods were applied to a study of the freshwater snail Lymnaea stagnalis L.. Data were obtained on the uptake and retention patterns of different oxidation states of 237 Pu and 241 Am at the organ and cellular levels of the pond snail. An attempt was made to relate the environmental chemistry of both radionuclides to the fixation in L. stagnalis. (author)

  4. Optimizing the design of a reproduction toxicity test with the pond snail Lymnaea stagnalis

    DEFF Research Database (Denmark)

    Charles, Sandrine; Ducrot, Virginie; Azam, Didier

    2016-01-01

    This paper presents the results from two ring-tests addressing the feasibility, robustness and reproducibility of a reproduction toxicity test with the freshwater gastropod Lymnaea stagnalis (RENILYS strain). Sixteen laboratories (from inexperienced to expert laboratories in mollusc testing) from...... nine countries participated in these ring-tests. Survival and reproduction were evaluated in L. stagnalis exposed to cadmium, tributyltin, prochloraz and trenbolone according to an OECD draft Test Guideline. In total, 49 datasets were analysed to assess the practicability of the proposed experimental...... protocol, and to estimate the between-laboratory reproducibility of toxicity endpoint values. The statistical analysis of count data (number of clutches or eggs per individual-day) leading to ECx estimation was specifically developed and automated through a free web-interface. Based on a complementary...

  5. Assessment of anoxia tolerance and photoperiod dependence of GABAergic polarity in the pond snail Lymnaea stagnalis.

    Science.gov (United States)

    Buck, Leslie T; Bond, Hilary C; Malik, Aqsa

    2017-01-01

    The pond snail Lymnaea stagnalis is reported to be anoxia-tolerant and if the tolerance mechanism is similar to that of the anoxia-tolerant painted turtle, GABA should play an important role. A potentially confounding factor investigating the role of GABA in anoxia tolerance are reports that GABA has both inhibitory and excitatory effects within L. stagnalis central ganglion. We therefore set out to determine if seasonality or photoperiod has an impact on: 1) the anoxia-tolerance of the intact pond snail, and 2) the response of isolated neuroganglia cluster F neurons to exogenous GABA application. L. stagnalis maintained on a natural summer light cycle were unable to survive any period of anoxic exposure, while those maintained on a natural winter light cycle survived a maximum of 4h. Using intracellular sharp electrode recordings from pedal ganglia cluster F neurons we show that there is a photoperiod dependent shift in the response to GABA. Snails exposed to a 16h:8h light:dark cycle in an environmental chamber (induced summer phenotype) exhibited hyperpolarizing inhibitory responses and those exposed to a 8h:16h light:dark cycle (induced winter phenotype) exhibited depolarizing excitatory responses to GABA application. Using gramicidin-perforated patch recordings we also found a photoperiod dependent shift in the reversal potential for GABA. We conclude that the opposing responses of L. stagnalis central neurons to GABA results from a shift in intracellular chloride concentration that is photoperiod dependent and is likely mediated through the relative efficacy of cation chloride co-transporters. Although the physiological ramifications of the photoperiod dependent shift are unknown this work potentially has important implications for the impact of artificial light pollution on animal health. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Optimizing the design of a reproduction toxicity test with the pond snail Lymnaea stagnalis.

    Science.gov (United States)

    Charles, Sandrine; Ducrot, Virginie; Azam, Didier; Benstead, Rachel; Brettschneider, Denise; De Schamphelaere, Karel; Filipe Goncalves, Sandra; Green, John W; Holbech, Henrik; Hutchinson, Thomas H; Faber, Daniel; Laranjeiro, Filipe; Matthiessen, Peter; Norrgren, Leif; Oehlmann, Jörg; Reategui-Zirena, Evelyn; Seeland-Fremer, Anne; Teigeler, Matthias; Thome, Jean-Pierre; Tobor Kaplon, Marysia; Weltje, Lennart; Lagadic, Laurent

    2016-11-01

    This paper presents the results from two ring-tests addressing the feasibility, robustness and reproducibility of a reproduction toxicity test with the freshwater gastropod Lymnaea stagnalis (RENILYS strain). Sixteen laboratories (from inexperienced to expert laboratories in mollusc testing) from nine countries participated in these ring-tests. Survival and reproduction were evaluated in L. stagnalis exposed to cadmium, tributyltin, prochloraz and trenbolone according to an OECD draft Test Guideline. In total, 49 datasets were analysed to assess the practicability of the proposed experimental protocol, and to estimate the between-laboratory reproducibility of toxicity endpoint values. The statistical analysis of count data (number of clutches or eggs per individual-day) leading to ECx estimation was specifically developed and automated through a free web-interface. Based on a complementary statistical analysis, the optimal test duration was established and the most sensitive and cost-effective reproduction toxicity endpoint was identified, to be used as the core endpoint. This validation process and the resulting optimized protocol were used to consolidate the OECD Test Guideline for the evaluation of reproductive effects of chemicals in L. stagnalis. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Sub-lethal cadmium exposure increases phytochelatin concentrations in the aquatic snail Lymnaea stagnalis

    Energy Technology Data Exchange (ETDEWEB)

    SF, Gonçalves [Department of Biology & CESAM, Centre for Environmental and Marine Studies, University of Aveiro, 3810-193 Aveiro (Portugal); SK, Davies [Department of Surgery and Cancer, Imperial College London, Sir Alexander Fleming Building, London SW7 2AZ (United Kingdom); Bennett, M. [Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, London SW7 2AZ (United Kingdom); Raab, A.; Feldmann, J. [TESLA, Department of Chemistry, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE, Scotland (United Kingdom); Kille, P. [Cardiff School of Biosciences, Cardiff University, Park Place, Cardiff CF10 3US (United Kingdom); Loureiro, S. [Department of Biology & CESAM, Centre for Environmental and Marine Studies, University of Aveiro, 3810-193 Aveiro (Portugal); DJ, Spurgeon [Centre for Ecology and Hydrology, Maclean Building, Benson Lane, Wallingford OX10 8BB (United Kingdom); JG, Bundy, E-mail: j.bundy@imperial.ac.uk [Department of Surgery and Cancer, Imperial College London, Sir Alexander Fleming Building, London SW7 2AZ (United Kingdom)

    2016-10-15

    Phytochelatins are metal-binding metabolites found in almost all plant species and some animal groups, including nematodes and annelids, where they can play an important role in detoxifying metals such as cadmium. Species from several other taxa contain a phytochelatin synthase (PCS) gene orthologue, including molluscs, indicating they may have the potential to synthesize phytochelatins. However, the presence of a gene alone does not demonstrate that it plays a functional role in metal detoxification. In the present study, we show that the aquatic snail Lymnaea stagnalis produced both penta- and heptapeptide phytochelatins (i.e. phytochelatin-2 and phytochelatin-3), and their levels increased in response to sub-lethal levels of cadmium. - Highlights: • Little is known about the role of phytochelatins in metal detoxification in animals. • We detected phytochelatins (PC{sub 2} and PC{sub 3}) in a mollusc species, Lymnaea stagnalis. • Phytochelatins increased in Lymnaea stagnalis when exposed to cadmium. • Future research on phytochelatin responses in molluscs would be valuable.

  8. [A rare case report of laryngeal leech infestation in a 70-year-old man].

    Science.gov (United States)

    Anajar, Said; Tatari, Mohammed; Hassnaoui, Jawad; Abada, Reda; Rouadi, Sami; Roubal, Mohammed; Mahtar, Mohammed

    2017-01-01

    Foreign bodies in the upper respiratory tract are one of the most difficult otolaryngological emergencies; leeches are a very rare foreign bodies in the world. We report the case of a 70-year-old man with no past medical history presenting with laryngeal dyspnea associated with low abundant paroxysmal hemoptysis. The patient underwent nasofibroscopy showing the presence of a living and mobile organism at the subglottic level evoking a leech. Extraction was carried out under local anesthesia using laryngoscope and Magill forceps. The presence of a leech as a foreign body in the upper respiratory tract should be suspected in patients with a recent history of consumption of non-potable water.

  9. Determining the appropriate number and duration of leech therapy in congested tissues using tissue spectrophotometry and laser Doppler flowmetry.

    Science.gov (United States)

    Rothenberger, Jens; Petersen, Wiebke; Schaller, Hans-Eberhard; Held, Manuel

    2016-11-01

    A universal protocol determining the number of leeches and their application time does not exist. The aim of this study, therefore, is to quantify perfusion dynamics in venous congested tissues after leech application to get more detailed information about changes due to leech-induced skin microcirculation and to evaluate the usability of the Oxygen to See (O2C) device in terms of determining the appropriate number of leeches and the duration of therapy. Twelve patients with the need for leech therapy participated in the study. Perfusion dynamics of the congested tissue was assessed using the O2C device, which determines blood flow (BF), the relative amount of hemoglobin (rHB), and the oxygen saturation (SO2). Measurements were carried out before leech application and on various intervals like 10 minutes, one hour, and three hours after leech application. The leech application effectuated after 10 minutes a nonsignificant perfusion improvement, which further increased after one hour with a significant reduction of the relative amount of hemoglobin and a significant increase of blood flow and oxygen saturation (BF= +56.7%; rHB= -25.5%; SO2= +53.7%). After three hours, the values returned to the levels before leech administration. In two cases, in which further administration of leeches within the measurement period was necessary, no substantial perfusion changes were obtained. The results of this study forms a more precise pattern of microcirculatory changes of leech therapy in congested tissues. According to our measurements a venous drainage improvement can be expected in congested tissue one hour after leech administration. The O2C seems to be a useful method to determine the appropriate number and duration of leech therapy. © 2016 by the Wound Healing Society.

  10. The Leech with a taste for oranges / Merje Järv-Griffiths

    Index Scriptorium Estoniae

    Järv-Griffiths, Merje

    2007-01-01

    Rockansamblist Leech (kontserdid 23. nov. klubis Rockstar's Tallinnas, 30. nov. Lutsu Teatris Tartus ja 21. dets. festivalil Green Christmas Rakveres), heliplaadist "Tram-O-Gram" (vt. www.leechband.net)

  11. Tyrannobdella rex n. gen. n. sp. and the evolutionary origins of mucosal leech infestations.

    Directory of Open Access Journals (Sweden)

    Anna J Phillips

    Full Text Available BACKGROUND: Leeches have gained a fearsome reputation by feeding externally on blood, often from human hosts. Orificial hirudiniasis is a condition in which a leech enters a body orifice, most often the nasopharyngeal region, but there are many cases of leeches infesting the eyes, urethra, vagina, or rectum. Several leech species particularly in Africa and Asia are well-known for their propensity to afflict humans. Because there has not previously been any data suggesting a close relationship for such geographically disparate species, this unnerving tendency to be invasive has been regarded only as a loathsome oddity and not a unifying character for a group of related organisms. PRINCIPAL FINDINGS: A new genus and species of leech from Perú was found feeding from the nasopharynx of humans. Unlike any other leech previously described, this new taxon has but a single jaw with very large teeth. Phylogenetic analyses of nuclear and mitochondrial genes using parsimony and Bayesian inference demonstrate that the new species belongs among a larger, global clade of leeches, all of which feed from the mucosal surfaces of mammals. CONCLUSIONS: This new species, found feeding from the upper respiratory tract of humans in Perú, clarifies an expansion of the family Praobdellidae to include the new species Tyrannobdella rex n. gen. n. sp., along with others in the genera Dinobdella, Myxobdella, Praobdella and Pintobdella. Moreover, the results clarify a single evolutionary origin of a group of leeches that specializes on mucous membranes, thus, posing a distinct threat to human health.

  12. Comparison of effect of nicotine and levamisole and ivermectin on mortality of leech

    Directory of Open Access Journals (Sweden)

    Mahmoud Bahmani

    2014-02-01

    Full Text Available Objective: To study the effect of different doses of nicotine on Limnatis in comparison with levamisole and ivermectin. Methods: In this interventional experimental study in July 2012, the amount of 61 mature leeches of Limnatis nilotica species were collected and anti-parasitic effects of drug treatments using anti-leech method were assessed. So that, a leech was placed in the dishes with 600 mL spring water and leech's paralysis and death time were recorded accurately for 720 min. A total of 9 replicates were considered for each treatment. Six drug treatments were considered. Pharmacological treatments include nicotine (5, 1 0 and 20 mg doses, levamisole (1 0 mg, ivermectin (10 mg and distilled water. Data were analyzed using the Sigma ASA 2 software and pair t-test method with less than 0.05 confidence levels. Results: The results of present study show that doses of 5, 10 and 20 mg of nicotine, with time average of 2.44依0.52, 1.88依0.78 and 1.55依0.72 min cause to death of leeches. Ivermectin and levamisole cause to death of leeches, averaging 7.44依1.12 and 14.66依5.09 min, respectively. Distilled water treatment has been reported as an ineffective group. Data analysis showed that the group receiving 5 mg nicotine, had minimum time of death and there are statistical differences among all groups (P>0.05, but there are not significant differences between treatments receiving 10 mg nicotine, with 5 and 20 mg nicotine treatments. Conclusions: It appears that nicotine compound as the effective substance of tobacco plant has the strong anti-leech effect on Limnatis nilotica species and can be used as leech purposes in the future.

  13. Cleft lip surgery in Anglo-Saxon Britain: the Leech Book (circa A.D. 920).

    Science.gov (United States)

    Vrebos, J

    1986-05-01

    The Leech Book, the oldest known Anglo-Saxon herbarium, probably written in Winchester, circa A.D. 920, by Cyril Bald or at his special request, contains a short chapter on the surgical treatment of the cleft lip; this chapter apparently represents the first record in a medical manuscript of this treatment. The original Anglo-Saxon text is presented together with transcriptions into more modern English. The general value of the Leech Book is briefly studied.

  14. Leech therapy- a holistic approach of treatment in unani (greeko-arab) medicine.

    Science.gov (United States)

    Lone, Azad Hussain; Ahmad, Tanzeel; Anwar, Mohd; Habib, Shahida; Sofi, Gh; Imam, Hashmat

    2011-07-01

    The Unani System of Medicine also known as Greeko-Arab medicine, founded by Hippocrates is based on the concept of equilibrium and balance of natural body humours (blood, bile, black bile and phlegm). The imbalance in the quality and quantity of these humours leads to diseases whereas restoration of this balance maintains health of a person. The treatment methodology of diseases is based on four therapeutic modalities viz. Regimental therapy, Dieto-therapy, Pharmacotherapy and surgery. Irsale Alaq (Leech or Hirudo therapy) is one of the most important and widely practised methods of regimental therapy used for local evacuation of morbid humours. It is a procedure of treatment with the use of medicinal leeches. It has been suggested and successfully practised by Greeko-Arab physicians in the management of musculoskeletal diseases, gynaecological disorders, chronic skin diseases, thromboembolic diseases, varicose veins, ENT disorders etc since long. According to Unani doctrine, the efficacy of leech therapy is attributed to the analgesic and resolvent activities of leeches. However, from modern perspective, the saliva of leech contains about 100 pharmacologically active biological substances like Hirudin, hyaluronidase, vasodilators, anesthetics, antibacterial, fibrinases, collagenase etc. These substances are injected into human body while sucking of the blood and are responsible for the analgesic, anti inflammatory and anesthetic effects of leech therapy.

  15. The Leech method for diagnosing constipation: intra- and interobserver variability and accuracy

    International Nuclear Information System (INIS)

    Lorijn, Fleur de; Voskuijl, Wieger P.; Taminiau, Jan A.; Benninga, Marc A.; Rijn, Rick R. van; Henneman, Onno D.F.; Heijmans, Jarom; Reitsma, Johannes B.

    2006-01-01

    The data concerning the value of a plain abdominal radiograph in childhood constipation are inconsistent. Recently, positive results have been reported of a new radiographic scoring system, ''the Leech method'', for assessing faecal loading. To assess intra- and interobserver variability and determine diagnostic accuracy of the Leech method in identifying children with functional constipation (FC). A total of 89 children (median age 9.8 years) with functional gastrointestinal disorders were included in the study. Based on clinical parameters, 52 fulfilled the criteria for FC, six fulfilled the criteria for functional abdominal pain (FAP), and 31 for functional non-retentive faecal incontinence (FNRFI); the latter two groups provided the controls. To assess intra- and interobserver variability of the Leech method three scorers scored the same abdominal radiograph twice. A Leech score of 9 or more was considered as suggestive of constipation. ROC analysis was used to determine the diagnostic accuracy of the Leech method in separating patients with FC from control patients. Significant intraobserver variability was found between two scorers (P=0.005 and P<0.0001), whereas there was no systematic difference between the two scores of the other scorer (P=0.89). The scores between scorers differed systematically and displayed large variability. The area under the ROC curve was 0.68 (95% CI 0.58-0.80), indicating poor diagnostic accuracy. The Leech scoring method for assessing faecal loading on a plain abdominal radiograph is of limited value in the diagnosis of FC in children. (orig.)

  16. Evidence of trophic transfer of microcystins from the gastropod Lymnaea stagnalis to the fish Gasterosteus aculeatus.

    Science.gov (United States)

    Lance, Emilie; Petit, Anais; Sanchez, Wilfried; Paty, Christelle; Gérard, Claudia; Bormans, Myriam

    2014-01-01

    According to our previous results the gastropod Lymnaea stagnalis exposed to MC-producing cyanobacteria accumulates microcystins (MCs) both as free and covalently bound forms in its tissues, therefore representing a potential risk of MC transfer through the food web. This study demonstrates in a laboratory experiment the transfer of free and bound MCs from L. stagnalis intoxicated by MC-producing Planktothrix agardhii ingestion to the fish Gasterosteus aculeatus. Fish were fed during five days with digestive glands of L. stagnalis containing various concentrations of free and bound MCs, then with toxin-free digestive glands during a 5-day depuration period. MC accumulation was measured in gastropod digestive gland and in various fish organs (liver, muscle, kidney, and gills). The impact on fish was evaluated through detoxification enzyme (glutathion-S-transferase, glutathion peroxydase and superoxyde dismutase) activities, hepatic histopathology, and modifications in gill ventilation, feeding and locomotion. G. aculeatus ingestion rate was similar with intoxicated and toxin-free diet. Fish accumulated MCs (up to 3.96±0.14μgg -1 DW) in all organs and in decreasing order in liver, muscle, kidney and gills. Hepatic histopathology was moderate. Glutathion peroxydase was activated in gills during intoxication suggesting a slight reactive oxygen species production, but without any impact on gill ventilation. Intoxication via ingestion of MC-intoxicated snails impacted fish locomotion. Intoxicated fish remained significantly less mobile than controls during the intoxication period possibly due to a lower health condition, whereas they showed a greater mobility during the depuration period that might be related to an acute foraging for food. During depuration, MC elimination was total in gills and kidney, but partial in liver and muscle. Our results assess the MC transfer from gastropods to fish and the potential risk induced by bound MCs in the food web. Copyright

  17. Some Biological Activities of Malaysian Leech Saliva Extract

    Directory of Open Access Journals (Sweden)

    Abdualrahman M. Abdualkader

    2011-12-01

    Full Text Available Normal 0 21 false false false MS X-NONE AR-SA Leeches were fed on the phagostimulatory solution through parafilm membrane. The satiated leeches were forced to regurgitate the solution by soaking them in an ice-container. The anticoagulant activity was ascertained using thrombin time assay (TT. The result revealed that the saliva concentration which increases TT by 100% (IC100 is 43.205µg/ml plasma. The antimicrobial activity of the saliva was tested against several bacterial spp. (E.coli, P.aeruginosa, B.cereus, Sal.typhi and S.aureus  and fungi spp. (C.albicans and C.neoformans. It was found that saliva has an inhibition activity against Sal.typhi (minimal inhibitory concentration MIC 78.253µg/ml, S.aureus (MIC 78.253µg/ml and E.coli (MIC 121.256µg/ml.ABSTRAK: Pacat-pacat diberi makan larutan phagostimulatory menerusi membran parafilem. Pacat-pacat yang kekenyangan itu dipaksa memuntahkan larutan tersebut dengan direndam di dalam bekas berisi ais. Aktiviti antigumpal ditentukan menggunakan cerakin masa trombin (TT. Keputusan menunjukkan kepekatan air liur pacat menyebabkan pertambahan TT sebanyak 100% (IC100 iaitu 43.205µg/ml plasma. Aktiviti antimikrob air liur telah diuji dengan pelbagai jenis bakteria (E.coli, P.aeruginosa, B.cereus, Sal.typhi dan S.aureus dan pelbagai jenis kulat (C.albicans and C.neoformans. Didapati air liur menghasilkan aktiviti perencatan terhadap Sal.typhi (kepekatan perencat minima (Minimal inhibitory concentration - MIC 78.253µg/ml, S.aureus (MIC 78.253µg/ml dan E.coli (MIC 121.256µg/ml.

  18. Rapid colonisation of Lymnaea stagnalis by larval trematodes in eutrophic ponds in central Europe

    Czech Academy of Sciences Publication Activity Database

    Soldánová, Miroslava; Kostadinova, Aneta

    2011-01-01

    Roč. 41, č. 9 (2011), 981-990 ISSN 0020-7519 R&D Projects: GA ČR GAP505/10/1562; GA ČR GD206/09/H026; GA MŠk LC522 Institutional research plan: CEZ:AV0Z60220518 Keywords : Lymnaea stagnalis * Freshwater pulmonate snail * Larval trematodes * Colonisation and extinction * Competition-colonisation trade-off * Eutrophic ponds * Central Europe Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 3.393, year: 2011

  19. Investigating apical adverse effects of four endocrine active substances in the freshwater gastropod Lymnaea stagnalis.

    Science.gov (United States)

    Giusti, Arnaud; Lagadic, Laurent; Barsi, Alpar; Thomé, Jean-Pierre; Joaquim-Justo, Célia; Ducrot, Virginie

    2014-09-15

    The hermaphroditic gastropod Lymnaea stagnalis is proposed as a candidate species for the development of OECD guidelines for testing of the reprotoxicity of chemicals, including endocrine active substances (EASs). Up to now, only a few putative EASs have been tested for their reproductive toxicity in this species. In this study, we investigate the effects of four EASs with different affinities to the vertebrate estrogen and androgen receptors (chlordecone as an estrogen; cyproterone acetate, fenitrothion and vinclozolin as anti-androgens) on the reproduction of L. stagnalis in a 21-day semi-static test. Testosterone and 17α-ethinylestradiol (EE2) were used as the reference compounds. The tested EASs had no significant effect on growth and survival at the tested concentration ranges (ng to μg/L). Classical reproduction endpoints (i.e., oviposition and fecundity) were not responsive to the tested chemicals, except for chlordecone and 17α-ethinylestradiol, which hampered reproduction from 19.6 μg/L and 17.6 μg/L, respectively. The frequency of polyembryonic eggs, used as an additional endpoint, demonstrated the effects of all compounds except EE2. The molecular pathways, which are involved in such reproduction impairments, remain unknown. Our results suggest that egg quality is a more sensitive endpoint as compared to other reproductive endpoints commonly assessed in mollusk toxicity tests. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Reproductive impacts of tributyltin (TBT) and triphenyltin (TPT) in the hermaphroditic freshwater gastropod Lymnaea stagnalis.

    Science.gov (United States)

    Giusti, Arnaud; Barsi, Alpar; Dugué, Maël; Collinet, Marc; Thomé, Jean-Pierre; Joaquim-Justo, Célia; Roig, Benoit; Lagadic, Laurent; Ducrot, Virginie

    2013-07-01

    Tributyltin (TBT) and triphenyltin (TPT) are emblematic endocrine disruptors, which have been mostly studied in gonochoric prosobranchs. Although both compounds can simultaneously occur in the environment, they have mainly been tested separately for their effects on snail reproduction. Because large discrepancies in experimental conditions occurred in these tests, the present study aimed to compare the relative toxicity of TBT and TPT under similar laboratory conditions in the range of 0 ng Sn/L to 600 ng Sn/L. Tests were performed on the simultaneous hermaphrodite Lymnaea stagnalis, a freshwater snail in which effects of TPT were unknown. Survival, shell length, and reproduction were monitored in a 21-d semistatic test. Frequency of abnormal eggs was assessed as an additional endpoint. Triphenyltin hampered survival while TBT did not. Major effects on shell solidity and reproduction were observed for both compounds, reproductive outputs being more severely hampered by TBT than by TPT. Considering the frequency of abnormal eggs allowed increasing test sensitivity, because snail responses to TBT could be detected at concentrations as low as 19 ng Sn/L. However, the putative mode of action of the 2 compounds could not be deduced from the structure of the molecules or from the response of apical endpoints. Sensitivity of L. stagnalis to TBT and TPT was compared with the sensitivity of prosobranch mollusks with different habitats and different reproductive strategies. Copyright © 2013 SETAC.

  1. Diet quality affects chemical tolerance in the freshwater snail Lymnaea stagnalis.

    Science.gov (United States)

    Fidder, Bridgette N; Reátegui-Zirena, Evelyn G; Salice, Christopher J

    2018-04-01

    Organisms generally select high-quality diets to obtain maximal energy while devoting the least amount of time and energy. Diets, however, can vary in natural systems. In ecotoxicological testing, the effect of diet type on organismal responses to toxicants has not been explored despite the potential for dietary effects to influence toxicological endpoints. We first evaluated diet quality using growth rate and sensitivity to the fungicide pyraclostrobin of Lymnaea stagnalis fed lettuce (common laboratory diet), turtle pellets (high nutrient composition), and a combination diet of both food items. We also measured the macronutrient content of snails raised on the multiple diets to determine how diet may have impacted energy allocation patterns. Finally, we evaluated whether snails discernibly preferred a particular diet. Snails fed high-nutrient and combination diets grew larger overall than snails fed a lettuce-only diet. Snails fed the high-nutrient and combination diets, both juvenile and adult, were significantly more tolerant to pyraclostrobin than snails fed lettuce. When measured for macronutrient content, snails raised on high-nutrient and combination diets had significantly higher carbohydrate content than snails fed lettuce. Despite the strong effects of diet type, snails did not exhibit a clear diet choice in preference trials. Dietary composition clearly influences growth rate, sensitivity, and macronutrient content of Lymnaea stagnalis. These results suggest that the nutritional environment has potentially strong impacts on toxicant sensitivity. Environ Toxicol Chem 2018;37:1158-1167. © 2017 SETAC. © 2017 SETAC.

  2. Allium sativum L.: the anti-immature leech (Limnatis nilotica) activity compared to Niclosomide.

    Science.gov (United States)

    Bahmani, Mahmoud; Abbasi, Javad; Mohsenzadegan, Ava; Sadeghian, Sirous; Ahangaran, Majid Gholami

    2013-03-01

    This study was carried out to determine the effects of methanolic extracts of Allium sativum L. on Limnatis nilotica compared with Niclosomide. In this experimental study in September 2010, a number of leeches (70 in total) from the southern area of Ilam province were prepared, and the effects of methanolic extract of A. sativum L. with Niclosomide as the control drug were compared and distilled water was evaluated as the placebo group which investigated L. nilotica using anti-leech assay. The average time of paralysis and death of L. nilotica for Niclosomide (1,250 mg/kg) and the methanol extract of A. sativum L. (600 μg/ml) were 6.22 ± 2.94 and 68.44 ± 28.39 min, respectively. Distilled water and garlic tablets at a dose of 400 mg were determined as the inert group. In this research, the attraction time of the leeches' death among different treatments is significant. In this study, it was determined that Niclosomide, with an intensity of 4+, and methanolic extracts of A. sativum L., with an intensity of 3+, have a good anti-leech effect and can be shown to be effective in cases of leech biting, while distilled water was negative.

  3. Intranasal leech (hirudiniasis) common mode of presentation and sites of lodgment

    International Nuclear Information System (INIS)

    Khan, K.A.; Rafique, A.; Rafique, A.; Babur, S.

    2013-01-01

    Objective: To assess the common mode of presentation and sites of lodgment in cases of nasal leech infestation. Design: Descriptive study. Place and Duration of Study: This study was conducted in the ENT Department of Shaikh Khalifa Bin Zayed Al Nahyan Hospital (CMH) Muzaffarabad from 10th Jan 2010 to 15th Feb 2012. Patients and Methods: After getting informed consent, total of 70 cases that fulfilled the inclusion criteria i.e patients irrespective of age and gender with a positive history of epistaxis and use of spring water for daily utilities and especially after exclusion of other known causes for epistaxis were included in this study. A thorough history followed by ENT examination including nasal endoscopy was carried out in each case and site of lodgment of leech documented. This was followed by removal of leech from nose. Results: The commonest mode of presentation of nasal leech was epistaxis (54.28%) and the commonest site of lodgment of leech was under the inferior turbinate (inferior meatus) (82.86%). Conclusion: This rare cause of epistaxis should be kept in mind once all other common causes are excluded especially if the patient belongs to low socioeconomic group and using fresh spring water for their consumption. A thorough search in the region of inferior meatus should be under taken aided by nasal endoscope if available. (author)

  4. Local (Malaysian Leech as Alternative Healing Treatment and an Islamic Perspective

    Directory of Open Access Journals (Sweden)

    ZULHISYAM, A. K.

    2016-12-01

    Full Text Available The therapy is known from the time of extreme antiquity, dating back more than 2,500 years ago and still being practiced nowadays. This fact testifies to its efficiency in various health problems. In some cases, traditional medical practitioners use leeches for therapeutic healing treatment which is known as ‘cupping’. Such remedial method is quickly gaining acceptance amongst the local folks which is now becoming a thriving business. Some have made this treatment as their main business even though the therapy is quite recent for people in this country. This article discusses the process of cupping by using leech in the Islamic perspective and also the uniqueness of the hirudin protein in leeches respectively.

  5. Transmitter-induced glycogenolysis and gluconeogenesis in leech segmental ganglia.

    Science.gov (United States)

    Pennington, A J; Pentreath, V W

    1987-01-01

    1. The utilization and control of glycogen stores were studied in the isolated segmental ganglia of the horse leech, Haemopis sanguisuga. The glycogen in the ganglia was extracted and assayed fluorimetrically and its cellular localization and turnover studied by autoradiography in conjunction with [3H] glucose. 2. The glycogen levels were measured after incubation with different neurotransmitters for 60 min at 28 degrees C. The results for each experimental ganglion were compared to a paired control ganglion, and the results analysed by paired t-tests. 3. Several transmitter substances (5-HT, octopamine, dopamine, noradrenaline, histamine) produced reductions in glycogen (glycogenolysis); other transmitters (glutamate, GABA) produced increases in glycogen (gluconeogenesis); others (adenosine, glycine) produced reductions or increases, depending on concentration. Acetylcholine had no effect on the glycogen levels. 4. Most of the glycogen in the ganglia is localized in the packet glial cells, which surround the neuron perikarya. Autoradiographic analysis demonstrated that the effects of histamine and dopamine were principally on the glycogen in the glial cells. 5. Adenylate cyclase was demonstrated by electron microscope histochemistry to be localized on the plasma membranes of the glial cells, and to a lesser extent on the neuronal membranes. 6. It is concluded that the changes in glycogen in the glial cells may be party controlled by transmitters via adenylate cyclase. This may provide a sensitive mechanism for coupling neuronal activity with energy metabolism.

  6. Probabilistic Seismic Hazard Analysis of Victoria, British Columbia, Canada: Considering an Active Leech River Fault

    Science.gov (United States)

    Kukovica, J.; Molnar, S.; Ghofrani, H.

    2017-12-01

    The Leech River fault is situated on Vancouver Island near the city of Victoria, British Columbia, Canada. The 60km transpressional reverse fault zone runs east to west along the southern tip of Vancouver Island, dividing the lithologic units of Jurassic-Cretaceous Leech River Complex schists to the north and Eocene Metchosin Formation basalts to the south. This fault system poses a considerable hazard due to its proximity to Victoria and 3 major hydroelectric dams. The Canadian seismic hazard model for the 2015 National Building Code of Canada (NBCC) considered the fault system to be inactive. However, recent paleoseismic evidence suggests there to be at least 2 surface-rupturing events to have exceeded a moment magnitude (M) of 6.5 within the last 15,000 years (Morell et al. 2017). We perform a Probabilistic Seismic Hazard Analysis (PSHA) for the city of Victoria with consideration of the Leech River fault as an active source. A PSHA for Victoria which replicates the 2015 NBCC estimates is accomplished to calibrate our PSHA procedure. The same seismic source zones, magnitude recurrence parameters, and Ground Motion Prediction Equations (GMPEs) are used. We replicate the uniform hazard spectrum for a probability of exceedance of 2% in 50 years for a 500 km radial area around Victoria. An active Leech River fault zone is then added; known length and dip. We are determining magnitude recurrence parameters based on a Gutenberg-Richter relationship for the Leech River fault from various catalogues of the recorded seismicity (M 2-3) within the fault's vicinity and the proposed paleoseismic events. We seek to understand whether inclusion of an active Leech River fault source will significantly increase the probabilistic seismic hazard for Victoria. Morell et al. 2017. Quaternary rupture of a crustal fault beneath Victoria, British Columbia, Canada. GSA Today, 27, doi: 10.1130/GSATG291A.1

  7. The Leech method for diagnosing constipation: intra- and interobserver variability and accuracy

    Energy Technology Data Exchange (ETDEWEB)

    Lorijn, Fleur de; Voskuijl, Wieger P.; Taminiau, Jan A.; Benninga, Marc A. [Emma Children' s Hospital, Department of Paediatric Gastroenterology and Nutrition, Amsterdam (Netherlands); Rijn, Rick R. van; Henneman, Onno D.F. [Academic Medical Centre, Department of Radiology, Amsterdam (Netherlands); Heijmans, Jarom [Emma Children' s Hospital, Department of Paediatric Gastroenterology and Nutrition, Amsterdam (Netherlands); Academic Medical Centre, Department of Radiology, Amsterdam (Netherlands); Reitsma, Johannes B. [Academic Medical Centre, Department of Clinical Epidemiology and Biostatistics, Amsterdam (Netherlands)

    2006-01-01

    The data concerning the value of a plain abdominal radiograph in childhood constipation are inconsistent. Recently, positive results have been reported of a new radiographic scoring system, ''the Leech method'', for assessing faecal loading. To assess intra- and interobserver variability and determine diagnostic accuracy of the Leech method in identifying children with functional constipation (FC). A total of 89 children (median age 9.8 years) with functional gastrointestinal disorders were included in the study. Based on clinical parameters, 52 fulfilled the criteria for FC, six fulfilled the criteria for functional abdominal pain (FAP), and 31 for functional non-retentive faecal incontinence (FNRFI); the latter two groups provided the controls. To assess intra- and interobserver variability of the Leech method three scorers scored the same abdominal radiograph twice. A Leech score of 9 or more was considered as suggestive of constipation. ROC analysis was used to determine the diagnostic accuracy of the Leech method in separating patients with FC from control patients. Significant intraobserver variability was found between two scorers (P=0.005 and P<0.0001), whereas there was no systematic difference between the two scores of the other scorer (P=0.89). The scores between scorers differed systematically and displayed large variability. The area under the ROC curve was 0.68 (95% CI 0.58-0.80), indicating poor diagnostic accuracy. The Leech scoring method for assessing faecal loading on a plain abdominal radiograph is of limited value in the diagnosis of FC in children. (orig.)

  8. Genetic assessment of leech species from yak (Bos grunniens) in the tract of Northeast India.

    Science.gov (United States)

    Chatterjee, Nilkantha; Dhar, Bishal; Bhattarcharya, Debasis; Deori, Sourabh; Doley, Juwar; Bam, Joken; Das, Pranab J; Bera, Asit K; Deb, Sitangshu M; Devi, Ningthoujam Neelima; Paul, Rajesh; Malvika, Sorokhaibam; Ghosh, Sankar Kumar

    2018-01-01

    Yak is an iconic symbol of Tibet and high altitudes of Northeast India. It is highly cherished for milk, meat, and skin. However, yaks suffer drastic change in milk production, weight loss, etc, when infested by parasites. Among them, infestation by leeches is a serious problem in the Himalayan belt of Northeast India. The parasite feeds on blood externally or from body orifices, like nasopharynx, oral, rectum, etc. But there has been limited data about the leech species infesting the yak in that region because of the difficulties in morphological identification due to plasticity of the body, changes in shape, and surface structure and thus, warrants for the molecular characterization of leech. In anticipation, this study would be influential in proper identification of leech species infesting yak track and also helpful in inventorying of leech species in Northeast India. Here, we investigated, through combined approach of molecular markers and morphological parameters for the identification of leech species infesting yak. The DNA sequences of COI barcode fragment, 18S and 28S rDNA, were analyzed for species identification. The generated sequences were subjected to similarity match in global database and analyzed further through Neighbour-Joining, K2P distance based as well as ML approach. Among the three markers, only COI was successful in delineating species whereas the 18S and 28S failed to delineate the species. Our study confirmed the presence of the species from genus Hirudinaria, Haemadipsa, Whitmania, and one species Myxobdella annandalae, which has not been previously reported from this region.

  9. Microsurgical replantation and postoperative leech treatment of a large severed nasal segment

    DEFF Research Database (Denmark)

    Stemann Andersen, Peter; Elberg, Jens Jørgen

    2012-01-01

    The survival of a microsurgically replanted segment of nose in a 41-year-old woman was facilitated by the assistance of the medicinal leech Hirudo medicinalis. An arterial microanastomosis was made to a severed partial segment of nose with no possibility of recreating a venous anastomosis. The re....... The resulting venous congestion was treated with nine days of treatment with a medical leech until venous neovascularisation had been achieved. At follow-up six months after discharge there was a well-heeled nasal segment and a satisfying functional - as well as cosmetic - result....

  10. Medicinal Leech Therapy for Glans Penis Congestion After Primary Bladder Exstrophy-Epispadias Repair in an Infant: A Case Report.

    Science.gov (United States)

    Wagenheim, Gavin N; Au, Jason; Gargollo, Patricio C

    2016-01-01

    Many postoperative complications have been reported after repair of classic bladder exstrophy. We present a case of medicinal leech therapy for glans penis congestion following exstrophy repair in an infant. A 2-week-old male with classic bladder exstrophy underwent complete primary repair. On postoperative day 1, he developed rapidly worsening glans penis venous congestion. Medicinal leech therapy was instituted with antibiotics and blood transfusions to maintain a hematocrit >30%. After 24 hours, venous congestion improved and therapy was discontinued. The patient's remaining hospital course was uncomplicated. Medicinal leeches are an effective therapy to relieve glans penis venous congestion. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Hydrogeology and ground-water quality of glacial-drift aquifers, Leech Lake Indian Reservation, north-central Minnesota

    Science.gov (United States)

    Lindgren, R.J.

    1996-01-01

    Among the duties of the water managers of the Leech Lake Indian Reservation in north-central Minnesota are the development and protection of the water resources of the Reservation. The U.S. Geological Survey, in cooperation with the Leech Lake Indian Reservation Business Committee, conducted a three and one half-year study (1988-91) of the ground-water resources of the Leech Lake Indian Reservation. The objectives of this study were to describe the availability and quality of ground water contained in glacial-drift aquifers underlying the Reservation.

  12. The leech nervous system: a valuable model to study the microglia involvement in regenerative processes.

    Science.gov (United States)

    Le Marrec-Croq, Françoise; Drago, Francesco; Vizioli, Jacopo; Sautière, Pierre-Eric; Lefebvre, Christophe

    2013-01-01

    Microglia are intrinsic components of the central nervous system (CNS). During pathologies in mammals, inflammatory processes implicate the resident microglia and the infiltration of blood cells including macrophages. Functions of microglia appear to be complex as they exhibit both neuroprotective and neurotoxic effects during neuropathological conditions in vivo and in vitro. The medicinal leech Hirudo medicinalis is a well-known model in neurobiology due to its ability to naturally repair its CNS following injury. Considering the low infiltration of blood cells in this process, the leech CNS is studied to specify the activation mechanisms of only resident microglial cells. The microglia recruitment is known to be essential for the usual sprouting of injured axons and does not require any other glial cells. The present review will describe the questions which are addressed to understand the nerve repair. They will discuss the implication of leech factors in the microglial accumulation, the identification of nerve cells producing these molecules, and the study of different microglial subsets. Those questions aim to better understand the mechanisms of microglial cell recruitment and their crosstalk with damaged neurons. The study of this dialog is necessary to elucidate the balance of the inflammation leading to the leech CNS repair.

  13. The Leech Nervous System: A Valuable Model to Study the Microglia Involvement in Regenerative Processes

    Directory of Open Access Journals (Sweden)

    Françoise Le Marrec-Croq

    2013-01-01

    Full Text Available Microglia are intrinsic components of the central nervous system (CNS. During pathologies in mammals, inflammatory processes implicate the resident microglia and the infiltration of blood cells including macrophages. Functions of microglia appear to be complex as they exhibit both neuroprotective and neurotoxic effects during neuropathological conditions in vivo and in vitro. The medicinal leech Hirudo medicinalis is a well-known model in neurobiology due to its ability to naturally repair its CNS following injury. Considering the low infiltration of blood cells in this process, the leech CNS is studied to specify the activation mechanisms of only resident microglial cells. The microglia recruitment is known to be essential for the usual sprouting of injured axons and does not require any other glial cells. The present review will describe the questions which are addressed to understand the nerve repair. They will discuss the implication of leech factors in the microglial accumulation, the identification of nerve cells producing these molecules, and the study of different microglial subsets. Those questions aim to better understand the mechanisms of microglial cell recruitment and their crosstalk with damaged neurons. The study of this dialog is necessary to elucidate the balance of the inflammation leading to the leech CNS repair.

  14. The Physiology and Mechanics of Undulatory Swimming: A Student Laboratory Exercise Using Medicinal Leeches

    Science.gov (United States)

    Ellerby, David J.

    2009-01-01

    The medicinal leech is a useful animal model for investigating undulatory swimming in the classroom. Unlike many swimming organisms, its swimming performance can be quantified without specialized equipment. A large blood meal alters swimming behavior in a way that can be used to generate a discussion of the hydrodynamics of swimming, muscle…

  15. Land Leeches of the g. Haemadipsa (Haemadipsoidea: Haemadipsidae). I. Conditions Essential to Laboratory Colonization.

    Science.gov (United States)

    1982-05-01

    minutes (44). Engorged haemadipsid leeches exhibit such obvious distension of their body that some observers have compared their appearance to...34 Jaws are muscular ridges set in the oral cavity, some armed with teeth, which incise the integument of the host to engorge on blood; one family

  16. Leech presence on Iberian Brown Frog, Rana iberica, (Amphibia: Anura: Ranidae from north-western Spain

    Directory of Open Access Journals (Sweden)

    César Ayres

    2008-12-01

    Full Text Available The authors describe a case of parasitism on Rana iberica by two species of leeches, Batracobdella sp. and Hirudo medicinalis, in a mountainous area of north-western Spain. Conservation implications of high parasite load on small and isolated populations are discussed.

  17. An unusual cause of severe dyspnea: A laryngeal live leech: Case report.

    Science.gov (United States)

    Anajar, Said; Ansari, Rachid; Hassnaoui, Jawad; Abada, Reda; Roubal, Mohammed; Mahtar, Mohammed

    2017-01-01

    Foreign bodies in the upper airways are one of the most challenging otolaryngology emergencies, leeches present a very rare cause of airway foreign bodies around the world. A 6-year-old girl was referred to our otolaryngology department at a tertiary university hospital with a severe dyspnea and hemoptysis. Nasofibroscopy revealed a dark living leech in the supraglottic area which extends to the glottis. The patient was urgently admitted to the operating room, the leech was grasped and removed with a foreign body forceps with a full length of more than 6cm. All symptoms were relieved post operatively and she was discharged one day later. Leeches should be suspected as an airway foreign body in patients with a recent history of drinking from stream water. Prevention remains the best treatment for such cases based simply on hygiene measures like not drinking stream water directly and filtering drinking water before it is used. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  18. Behavioral choice across leech species: chacun à son goût.

    Science.gov (United States)

    Gaudry, Q; Ruiz, N; Huang, T; Kristan, W B; Kristan, W B

    2010-04-01

    At any one time, animals are simultaneously bombarded with many sensory stimuli, but they typically choose to respond to only a few of them. We used multidimensional analysis to determine the behavioral responses of six species of leeches to stimulation, as the responses are affected by species identity, diet, behavioral state and stimulus location. Our results show that each of the species tested while not feeding displayed remarkably similar behaviors in response to tactile stimulation of the surface of the body. When not feeding, stimulus location was the most reliable factor in determining behavioral response. While feeding, the three sanguivorous (bloodsucking) species tested ignored stimulation, whereas the three carnivorous leeches abandoned feeding in favor of locomotory responses, regardless of phylogenetic relationships. In the sanguivorous leeches, feeding abolished all mechanically elicited responses and mechanical stimulation in turn had no effect on feeding. We also show that the behavioral hierarchy of leeches was fixed and unchanging even in species that can consume both a carnivorous and a sanguivorous diet.

  19. Field evidence for leech-borne transmission of amphibian Ichthyophonus sp.

    Science.gov (United States)

    Raffel, Thomas R; Dillard, James R; Hudson, Peter J

    2006-12-01

    Parasites have been implicated in mass mortality events and population declines of amphibians around the world. One pathogen associated with mortality events in North America is an Ichthyophonus sp.-like organism that affects red-spotted newts (Notophthalmus viridescens) and several frog species, yet little is known about the distribution of this pathogen in wild populations or the mechanism of transmission. In an effort to identify factors influencing the distribution and abundance of this pathogen, we measured Ichthyophonus sp. prevalence and a series of factors that could contribute to transmission in 16 newt populations during spring 2004. In contrast to our initial hypotheses of trophic transmission, several lines of evidence suggested a role for the amphibian leech (Placobdella picta) in Ichthyophonus sp. transmission. We propose the mechanistic hypothesis that a leech acquires Ichthyophonus sp. infection when inserting its proboscis into the muscles beneath the skin of infected newts and transmits the infection to other newts in subsequent feeding bouts. We also found effects of host sex, body mass, and breeding condition on Ichthyophonus sp. prevalence and the number of attached leeches. The number of leeches attached to newts was strongly related to the proportion of newt habitat containing emergent vegetation, suggesting that anthropogenic eutrophication might lead to more frequent or severe outbreaks of Ichthyophonus sp. infection in amphibians.

  20. An unusual cause of severe dyspnea: A laryngeal live leech: Case report

    Directory of Open Access Journals (Sweden)

    Said Anajar

    2017-01-01

    Conclusion: Leeches should be suspected as an airway foreign body in patients with a recent history of drinking from stream water. Prevention remains the best treatment for such cases based simply on hygiene measures like not drinking stream water directly and filtering drinking water before it is used.

  1. Intracellular recording, sensory field mapping, and culturing identified neurons in the leech, Hirudo medicinalis.

    Science.gov (United States)

    Titlow, Josh; Majeed, Zana R; Nicholls, John G; Cooper, Robin L

    2013-11-04

    The freshwater leech, Hirudo medicinalis, is a versatile model organism that has been used to address scientific questions in the fields of neurophysiology, neuroethology, and developmental biology. The goal of this report is to consolidate experimental techniques from the leech system into a single article that will be of use to physiologists with expertise in other nervous system preparations, or to biology students with little or no electrophysiology experience. We demonstrate how to dissect the leech for recording intracellularly from identified neural circuits in the ganglion. Next we show how individual cells of known function can be removed from the ganglion to be cultured in a Petri dish, and how to record from those neurons in culture. Then we demonstrate how to prepare a patch of innervated skin to be used for mapping sensory or motor fields. These leech preparations are still widely used to address basic electrical properties of neural networks, behavior, synaptogenesis, and development. They are also an appropriate training module for neuroscience or physiology teaching laboratories.

  2. Proteomic Analysis of the Reproductive Organs of the Hermaphroditic Gastropod Lymnaea stagnalis Exposed to Different Endocrine Disrupting Chemicals

    Science.gov (United States)

    Giusti, Arnaud; Leprince, Pierre; Mazzucchelli, Gabriel; Thomé, Jean-Pierre; Lagadic, Laurent; Ducrot, Virginie; Joaquim-Justo, Célia

    2013-01-01

    Many studies have reported perturbations of mollusc reproduction following exposure to low concentrations (ng/L range) of endocrine disrupting chemicals (EDCs). However, the mechanisms of action of these molecules on molluscs are still poorly understood. Investigation of the modifications of protein expression in organisms exposed to chemicals using proteomic methods can provide a broader and more comprehensive understanding of adverse impacts of pollution on organisms than conventional biochemical biomarkers (e.g., heat-shock proteins, metallothioneins, GST, EROD). In this study we have investigated the impacts of four chemicals, which exhibit different endocrine disrupting properties in vertebrates, on the proteome of the hermaphroditic freshwater pulmonate gastropod Lymnaea stagnalis after 21 days of exposure. Testosterone, tributyltin, chlordecone and cyproterone acetate were chosen as tested compounds as they can induce adverse effects on the reproduction of this snail. The 2D-DIGE method was used to identify proteins whose expression was affected by these compounds. In addition to modifying the expression of proteins involved in the structure and function of the cytoskeleton, chemicals had impacts on the expression of proteins involved in the reproduction of L. stagnalis. Exposure to 19.2 µg/L of chlordecone increased the abundance of ovipostatin, a peptide transmitted during mating through seminal fluid, which reduces oviposition in this species. The expression of yolk ferritin, the vitellogenin equivalent in L. stagnalis, was reduced after exposure to 94.2 ng Sn/L of tributyltin. The identification of yolk ferritin and the modification of its expression in snails exposed to chemicals were refined using western blot analysis. Our results showed that the tested compounds influenced the abundance of yolk ferritin in the reproductive organs. Alteration in proteins involved in reproductive pathways (e.g., ovipostatin and yolk ferritin) could constitute relevant

  3. Proteomic analysis of the reproductive organs of the hermaphroditic gastropod Lymnaea stagnalis exposed to different endocrine disrupting chemicals.

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    Arnaud Giusti

    Full Text Available Many studies have reported perturbations of mollusc reproduction following exposure to low concentrations (ng/L range of endocrine disrupting chemicals (EDCs. However, the mechanisms of action of these molecules on molluscs are still poorly understood. Investigation of the modifications of protein expression in organisms exposed to chemicals using proteomic methods can provide a broader and more comprehensive understanding of adverse impacts of pollution on organisms than conventional biochemical biomarkers (e.g., heat-shock proteins, metallothioneins, GST, EROD. In this study we have investigated the impacts of four chemicals, which exhibit different endocrine disrupting properties in vertebrates, on the proteome of the hermaphroditic freshwater pulmonate gastropod Lymnaea stagnalis after 21 days of exposure. Testosterone, tributyltin, chlordecone and cyproterone acetate were chosen as tested compounds as they can induce adverse effects on the reproduction of this snail. The 2D-DIGE method was used to identify proteins whose expression was affected by these compounds. In addition to modifying the expression of proteins involved in the structure and function of the cytoskeleton, chemicals had impacts on the expression of proteins involved in the reproduction of L. stagnalis. Exposure to 19.2 µg/L of chlordecone increased the abundance of ovipostatin, a peptide transmitted during mating through seminal fluid, which reduces oviposition in this species. The expression of yolk ferritin, the vitellogenin equivalent in L. stagnalis, was reduced after exposure to 94.2 ng Sn/L of tributyltin. The identification of yolk ferritin and the modification of its expression in snails exposed to chemicals were refined using western blot analysis. Our results showed that the tested compounds influenced the abundance of yolk ferritin in the reproductive organs. Alteration in proteins involved in reproductive pathways (e.g., ovipostatin and yolk ferritin could

  4. Genetic variation of Lymnaea stagnalis tolerance to copper: A test of selection hypotheses and its relevance for ecological risk assessment

    International Nuclear Information System (INIS)

    Côte, Jessica; Bouétard, Anthony; Pronost, Yannick; Besnard, Anne-Laure; Coke, Maïra; Piquet, Fabien; Caquet, Thierry; Coutellec, Marie-Agnès

    2015-01-01

    The use of standardized monospecific testing to assess the ecological risk of chemicals implicitly relies on the strong assumption that intraspecific variation in sensitivity is negligible or irrelevant in this context. In this study, we investigated genetic variation in copper sensitivity of the freshwater snail Lymnaea stagnalis, using lineages stemming from eight natural populations or strains found to be genetically differentiated at neutral markers. Copper-induced mortality varied widely among populations, as did the estimated daily death rate and time to 50% mortality (LT50). Population genetic divergence in copper sensitivity was compared to neutral differentiation using the Q ST -F ST approach. No evidence for homogenizing selection could be detected. This result demonstrates that species-level extrapolations from single population studies are highly unreliable. The study provides a simple example of how evolutionary principles could be incorporated into ecotoxicity testing in order to refine ecological risk assessment. - Highlights: • Genetic variation in copper tolerance occurs between Lymnaea stagnalis populations. • We used the Q ST -F ST approach to test evolutionary patterns in copper tolerance. • No evidence for uniform selection was found. • Results suggest that extrapolations to the species level are not safe. • A method is proposed to refine ecological risk assessment using genetic parameters. - Genetic variation in copper tolerance occurs in Lymnaea stagnalis. A method is proposed for considering evolutionary parameters in ecological risk assessment

  5. Infections following the application of leeches: two case reports and review of the literature

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    Maetz Benjamin

    2012-10-01

    Full Text Available Abstract Introduction Since the 1980s, leeches have been ingeniously used in the management of venous flap congestion. The presence of anticoagulative substances in their saliva improves the blood drainage. Their digestive tract contains several bacterial species, the main ones being Aeromonas hydrophila and Aeromonas veronii biovar sobria, which contribute to the digestion of ingested blood. These bacteria can be the cause of infections. Case presentation We report two cases of septicemia related to Aeromonas veronii biovar sobria that presented after leeches had been applied to congested transverse rectus abdominis myocutaneous flaps for delayed mammary reconstructions. Patient number 1 was a 55-year-old Caucasian woman who underwent a delayed breast reconstruction procedure. On the sixth postoperative day she showed a clinical presentation of septicemia. Aeromonas veronii biovar sobria was identified in the patient’s skin and blood bacteriological samples. Her fever ceased after 4 days of antibiotic treatment. Patient number 2 was a 56-year-old Caucasian woman who underwent a delayed breast reconstruction procedure. On the seventh postoperative day we noticed that she showed a clinical presentation of septicemia. Aeromonas veronii biovar sobria was identified in the patient’s blood cultures and local bacteriological samples. An antibiogram showed resistance to amoxicillin/clavulanic acid. Her fever ceased on the eleventh postoperative day after 4 days of antibiotic treatment. Conclusion The rate of infection after application of leeches is not negligible. The concentration of Aeromonas inside the digestive tracts of leeches largely decreases when the patient is under antibiotic therapy. These germs are sensitive to third-generation cephalosporins and fluoroquinolones and resistant to amoxicillin/clavulanic acid. We recommend preventive treatment based on classical measures of asepsis and on oral antibioprophylaxy with a fluoroquinolone

  6. A comparison study on the anti-leech effects of onion (Allium cepa L and ginger (Zingiber officinale with levamisole and triclabendazole

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    Bahmani Mahmoud

    2013-01-01

    Full Text Available Introduction: Leech may indwell in mucosa of the pharynx, tonsil, esophagus, nose, nasopharyngeal and rarely in larynx of hosts, however, the effective drugs against this parasite is scarce. This study was aimed to evaluate and compare the anti-leech effect of methanolic extract of onion (Allium cepa L and ginger (Zingiber officinale with levamisole and triclabendazole. Materials and Methods: In this study, 60 leeches (Limnatis nilotica were collected from south of Ilam. The anti-leech effect of methanolic extract of onion and ginger in comparison with levamisole and triclabendazole drugs (positive controls were evaluated. Distilled water was used as negative control. Paralysis and death of leeches were recorded in 720 minutes. Results: Lethal effect of methanolic extract of ginger against Limnatis nilotica was equal to levamisole and more than triclabendazole and methanolic extract of onion. Conclusion: Ginger equal to levamisole has anti-leech activity and its methanolic extract might be used against Limnatis nilotica.

  7. Protein kinase C mediates memory consolidation of taste avoidance conditioning in Lymnaea stagnalis.

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    Takigami, Satoshi; Sunada, Hiroshi; Lukowiak, Ken; Kuzirian, Alan M; Alkon, Daniel L; Sakakibara, Manabu

    2014-05-01

    In Lymnaea stagnalis, in order to obtain a 10 min short-term memory (STM) of taste avoidance conditioning (TAC) at least 10 paired presentations of a conditioned stimulus (CS), sucrose, and an unconditioned stimulus (US), tactile stimulation to the animal's head, are required. Pre-exposure of snails to the protein kinase C (PKC) α and ε activator bryostatin (Bryo) facilitated STM formation in that only 5 paired CS-US trials were required. Typically 20 paired presentations of the CS-US are required for formation of STM and LTM. However, 20 paired presentations do not result in STM or LTM if snails are pre-incubated with a PKC inhibitor, Ro-32-0432. We also found that LTM lasting longer than 48 h was acquired with Bryo incubation for 45 min even after termination of the conditioning paradigm. These data suggest that activation of the α and ε isozymes of PKC is crucially involved in the formation of LTM and provide further support for a mechanism that has been conserved across the evolution of species ranging from invertebrate molluscs to higher mammals. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Crystal structures of Lymnaea stagnalis AChBP in complex with neonicotinoid insecticides imidacloprid and clothianidin.

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    Ihara, Makoto; Okajima, Toshihide; Yamashita, Atsuko; Oda, Takuma; Hirata, Koichi; Nishiwaki, Hisashi; Morimoto, Takako; Akamatsu, Miki; Ashikawa, Yuji; Kuroda, Shun'ichi; Mega, Ryosuke; Kuramitsu, Seiki; Sattelle, David B; Matsuda, Kazuhiko

    2008-06-01

    Neonicotinoid insecticides, which act on nicotinic acetylcholine receptors (nAChRs) in a variety of ways, have extremely low mammalian toxicity, yet the molecular basis of such actions is poorly understood. To elucidate the molecular basis for nAChR-neonicotinoid interactions, a surrogate protein, acetylcholine binding protein from Lymnaea stagnalis (Ls-AChBP) was crystallized in complex with neonicotinoid insecticides imidacloprid (IMI) or clothianidin (CTD). The crystal structures suggested that the guanidine moiety of IMI and CTD stacks with Tyr185, while the nitro group of IMI but not of CTD makes a hydrogen bond with Gln55. IMI showed higher binding affinity for Ls-AChBP than that of CTD, consistent with weaker CH-pi interactions in the Ls-AChBP-CTD complex than in the Ls-AChBP-IMI complex and the lack of the nitro group-Gln55 hydrogen bond in CTD. Yet, the NH at position 1 of CTD makes a hydrogen bond with the backbone carbonyl of Trp143, offering an explanation for the diverse actions of neonicotinoids on nAChRs.

  9. Sensory mediation of memory blocking stressors in the pond snail Lymnaea stagnalis.

    Science.gov (United States)

    Dalesman, Sarah; Karnik, Vikram; Lukowiak, Ken

    2011-08-01

    The great pond snail, Lymnaea stagnalis, is commonly used as a model species to study how stress affects the ability to form long-term memory (LTM); however, we still have little information about how the snail senses stressful stimuli. The osphradium is an external sensory organ that demonstrates electrophysiological responses to a variety of external chemical stimuli. We examined the role, if any, played by the osphradium in sensing two environmental stressors, crowding and low environmental calcium, both known to block LTM in intact animals. We severed the osphradial nerve, blocking external sensory input from this organ to the central nervous system, and then exposed the snails to low environmental calcium or crowding stress to assess whether these stressors continued to block LTM formation. When exposed to low environmental calcium, snails with their osphradial nerve severed responded as if they were maintained in our standard calcium environment. That is, they did not respond to low calcium as a stressor blocking LTM; therefore, the osphradium plays a crucial role in mediating how snails respond to this stressor. However, following crowding, LTM formation was blocked in both control groups and snails that had the osphradial nerve severed, indicating that sensory information from the osphradium is not required to sense crowded conditions. Together these data show that two stressors that result in the same behavioural phenotype, blocking LTM formation, do so via two distinct sensory pathways.

  10. Exotic Homoclinic Surface of a Saddle-Node Limit Cycle in a Leech Neuron Model

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    Yooer, Chi-Feng; Wei, Fang; Xu, Jian-Xue; Zhang, Xin-Hua

    2011-03-01

    We carry out numerical and theoretical investigations on the global unstable invariant set (manifold) of a saddle-node limit cycle in a leech heart interneuron model. The corresponding global bifurcation is accompanied by an explosion of secondary bifurcations of limit cycles and the emergence of loop-shaped bifurcation structures. The dynamical behaviors of the trajectories of the invariant set are very complicated and can only be partially explained by existing theories.

  11. A new lineage of trypanosomes from Australian vertebrates and terrestrial bloodsucking leeches (Haemadipsidae).

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    Hamilton, P B; Stevens, J R; Gidley, J; Holz, P; Gibson, W C

    2005-04-01

    Little is known about the trypanosomes of indigenous Australian vertebrates and their vectors. We surveyed a range of vertebrates and blood-feeding invertebrates for trypanosomes by parasitological and PCR-based methods using primers specific to the small subunit ribosomal RNA (SSU rRNA) gene of genus Trypanosoma. Trypanosome isolates were obtained in culture from two common wombats, one swamp wallaby and an Australian bird (Strepera sp.). By PCR, blood samples from three wombats, one brush-tailed wallaby, three platypuses and a frog were positive for trypanosome DNA. All the blood-sucking invertebrates screened were negative for trypanosomes both by microscopy and PCR, except for specimens of terrestrial leeches (Haemadipsidae). Of the latter, two Micobdella sp. specimens from Victoria and 18 Philaemon sp. specimens from Queensland were positive by PCR. Four Haemadipsa zeylanica specimens from Sri Lanka and three Leiobdella jawarerensis specimens from Papua New Guinea were also PCR positive for trypanosome DNA. We sequenced the SSU rRNA and glycosomal glyceraldehyde phosphate dehydrogenase (gGAPDH) genes in order to determine the phylogenetic positions of the new vertebrate and terrestrial leech trypanosomes. In trees based on these genes, Australian vertebrate trypanosomes fell in several distinct clades, for the most part being more closely related to trypanosomes outside Australia than to each other. Two previously undescribed wallaby trypanosomes fell in a clade with Trypanosoma theileri, the cosmopolitan bovid trypanosome, and Trypanosoma cyclops from a Malaysian primate. The terrestrial leech trypanosomes were closely related to the wallaby trypanosomes, T. cyclops and a trypanosome from an Australian frog. We suggest that haemadipsid leeches may be significant and widespread vectors of trypanosomes in Australia and Asia.

  12. Human recombinant RNASET2-induced inflammatory response and connective tissue remodeling in the medicinal leech.

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    Baranzini, Nicolò; Pedrini, Edoardo; Girardello, Rossana; Tettamanti, Gianluca; de Eguileor, Magda; Taramelli, Roberto; Acquati, Francesco; Grimaldi, Annalisa

    2017-05-01

    In recent years, several studies have demonstrated that the RNASET2 gene is involved in the control of tumorigenicity in ovarian cancer cells. Furthermore, a role in establishing a functional cross-talk between cancer cells and the surrounding tumor microenvironment has been unveiled for this gene, based on its ability to act as an inducer of the innate immune response. Although several studies have reported on the molecular features of RNASET2, the details on the mechanisms by which this evolutionarily conserved ribonuclease regulates the immune system are still poorly defined. In the effort to clarify this aspect, we report here the effect of recombinant human RNASET2 injection and its role in regulating the innate immune response after bacterial challenge in an invertebrate model, the medicinal leech. We found that recombinant RNASET2 injection induces fibroplasias, connective tissue remodeling and the recruitment of numerous infiltrating cells expressing the specific macrophage markers CD68 and HmAIF1. The RNASET2-mediated chemotactic activity for macrophages has been further confirmed by using a consolidated experimental approach based on injection of the Matrigel biomatrice (MG) supplemented with recombinant RNASET2 in the leech body wall. One week after injection, a large number of CD68 + and HmAIF-1 + macrophages massively infiltrated MG sponges. Finally, in leeches challenged with lipopolysaccharides (LPS) or with the environmental bacteria pathogen Micrococcus nishinomiyaensis, numerous macrophages migrating to the site of inoculation expressed high levels of endogenous RNASET2. Taken together, these results suggest that RNASET2 is likely involved in the initial phase of the inflammatory response in leeches.

  13. Multiple changes in peptide and lipid expression associated with regeneration in the nervous system of the medicinal leech.

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    Céline Meriaux

    2011-04-01

    Full Text Available The adult medicinal leech central nervous system (CNS is capable of regenerating specific synaptic circuitry after a mechanical lesion, displaying evidence of anatomical repair within a few days and functional recovery within a few weeks. In the present work, spatiotemporal changes in molecular distributions during this phenomenon are explored. Moreover, the hypothesis that neural regeneration involves some molecular factors initially employed during embryonic neural development is tested.Imaging mass spectrometry coupled to peptidomic and lipidomic methodologies allowed the selection of molecules whose spatiotemporal pattern of expression was of potential interest. The identification of peptides was aided by comparing MS/MS spectra obtained for the peptidome extracted from embryonic and adult tissues to leech transcriptome and genome databases. Through the parallel use of a classical lipidomic approach and secondary ion mass spectrometry, specific lipids, including cannabinoids, gangliosides and several other types, were detected in adult ganglia following mechanical damage to connected nerves. These observations motivated a search for possible effects of cannabinoids on neurite outgrowth. Exposing nervous tissues to Transient Receptor Potential Vanilloid (TRPV receptor agonists resulted in enhanced neurite outgrowth from a cut nerve, while exposure to antagonists blocked such outgrowth.The experiments on the regenerating adult leech CNS reported here provide direct evidence of increased titers of proteins that are thought to play important roles in early stages of neural development. Our data further suggest that endocannabinoids also play key roles in CNS regeneration, mediated through the activation of leech TRPVs, as a thorough search of leech genome databases failed to reveal any leech orthologs of the mammalian cannabinoid receptors but revealed putative TRPVs. In sum, our observations identify a number of lipids and proteins that may

  14. Experimental Investigation on the Morphology and Adhesion Mechanism of Leech Posterior Suckers.

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    Huashan Feng

    Full Text Available The posterior sucker of a leech represents a fascinating natural system that allows the leech to adhere to different terrains and substrates. However, the mechanism of adhesion and desorption has not yet to be elucidated. In order to better understand how the adhesion is performed, we analyzed the surface structure, adsorption movements, the muscles' distribution, physical characteristics, and the adsorption force of the leech posterior suckers by experimental investigation. Three conclusions can be drawn based on the obtained experimental results. First, the adhesion by the posterior sucker is wet adhesion, because the surface of the posterior sucker is smooth and the sealing can only be achieved on wet surfaces. Second, the deformation texture, consisting of soft collagen tissues and highly ductile epidermal tissues, plays a key role in adhering to rough surfaces. Finally, the adhesion and desorption is achieved by the synergetic operation of six muscle fibers working in different directions. Concrete saying, directional deformation of the collagen/epithermal interface driven by spatially-distributed muscle fibers facilitates the excretion of fluids in the sucker venter, thus allowing liquid sealing. Furthermore, we found that the adhesion strength is directly related to the size of the contact surface which is generated and affected by the sucker deformation. Such an underlying physical mechanism offers potential cues for developing innovative bio-inspired artificial adhesion systems.

  15. Interactions between cyanobacteria and gastropods II. Impact of toxic Planktothrix agardhii on the life-history traits of Lymnaea stagnalis.

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    Lance, Emilie; Paty, Chrystelle; Bormans, Myriam; Brient, Luc; Gérard, Claudia

    2007-03-30

    Hepatotoxins are frequently produced by many cyanobacterial species. Microcystins (MCs) are the most frequent and widely studied hepatotoxins, with potentially hazardous repercussions on aquatic organisms. As a ubiquitous herbivore living in eutrophic freshwaters, the snail Lymnaea stagnalis (Gastropoda: Pulmonata) is particularly exposed to cyanobacteria. The toxic filamentous Planktothrix agardhii is common in temperate lakes and is therefore, a potential food resource for gastropods. In the first part of this study, we demonstrated the ingestion of toxic P. agardhii by L. stagnalis during a 5 weeks exposure, with concomitant accumulation of, on average, 60% of total MCs ingested. After 3 weeks of non-toxic food (lettuce), approximately 90% of MCs were eliminated from tissues. Here, we investigate the impact of toxic P. agardhii consumption on the life-history traits (survival, growth and fecundity), locomotion and the structure of digestive and genital glands of juvenile and adult L. stagnalis. We observed a decrease of growth regardless of age, although this was more marked in juveniles, and a reduction of fecundity in adults. Survival and locomotion were not affected. Reduction of growth and fecundity continued to be observed even after feeding of non-toxic food for 3 weeks. The structure of the digestive gland was altered during the intoxication period but not irreversibly as cells tended to recover a normal status after the 3-week detoxification period. No histopathological changes occurred in the genital gland and oocytes, and spermatozoids were present in the gonadic acini. The density of cyanobacterial suspensions used in this study was comparable to those regularly observed in lakes, particularly in eutrophic waters. These results are discussed in terms of the negative impact of toxic cyanobacteria on natural communities of freshwater gastropods, and potential cascading effects on the equilibrium and functioning of the ecosystem.

  16. Does water chemistry affect the dietary uptake and toxicity of silver nanoparticles by the freshwater snail Lymnaea stagnalis?

    International Nuclear Information System (INIS)

    Oliver, Ana López-Serrano; Croteau, Marie-Noële; Stoiber, Tasha L.; Tejamaya, Mila; Römer, Isabella; Lead, Jamie R.; Luoma, Samuel N.

    2014-01-01

    Silver nanoparticles (AgNPs) are widely used in many applications and likely released into the aquatic environment. There is increasing evidence that Ag is efficiently delivered to aquatic organisms from AgNPs after aqueous and dietary exposures. Accumulation of AgNPs through the diet can damage digestion and adversely affect growth. It is well recognized that aspects of water quality, such as hardness, affect the bioavailability and toxicity of waterborne Ag. However, the influence of water chemistry on the bioavailability and toxicity of dietborne AgNPs to aquatic invertebrates is largely unknown. Here we characterize for the first time the effects of water hardness and humic acids on the bioaccumulation and toxicity of AgNPs coated with polyvinyl pyrrolidone (PVP) to the freshwater snail Lymnaea stagnalis after dietary exposures. Our results indicate that bioaccumulation and toxicity of Ag from PVP-AgNPs ingested with food are not affected by water hardness and by humic acids, although both could affect interactions with the biological membrane and trigger nanoparticle transformations. Snails efficiently assimilated Ag from the PVP-AgNPs mixed with diatoms (Ag assimilation efficiencies ranged from 82 to 93%). Rate constants of Ag uptake from food were similar across the entire range of water hardness and humic acid concentrations. These results suggest that correcting regulations for water quality could be irrelevant and ineffective where dietary exposure is important. - Highlights: • AgNP coated with polyvinyl pyrrolidone (PVP), PVP-AgNP were efficiently assimilated by Lymnaea stagnalis. • Water chemistry has no influence on the dietary uptake of PVP-AgNP by snails. - L. Stagnalis assimilated PVP-AgNPs efficiently from food and water chemistry had no influence on their uptake and toxicity

  17. On the Ultrastructure and Function of Rhogocytes from the Pond Snail Lymnaea stagnalis.

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    Maria Kokkinopoulou

    Full Text Available Rhogocytes, also termed "pore cells", occur as solitary or clustered cells in the connective tissue of gastropod molluscs. Rhogocytes possess an enveloping lamina of extracellular matrix and enigmatic extracellular lacunae bridged by cytoplasmic bars that form 20 nm diaphragmatic slits likely to act as a molecular sieve. Recent papers highlight the embryogenesis and ultrastructure of these cells, and their role in heavy metal detoxification. Rhogocytes are the site of hemocyanin or hemoglobin biosynthesis in gastropods. Based on electron microscopy, we recently proposed a possible pathway of hemoglobin exocytosis through the slit apparatus, and provided molecular evidence of a common phylogenetic origin of molluscan rhogocytes, insect nephrocytes and vertebrate podocytes. However, the previously proposed secretion mode of the respiratory proteins into the hemolymph is still rather hypothetical, and the possible role of rhogocytes in detoxification requires additional data. Although our previous study on rhogocytes of the red-blooded (hemoglobin-containing freshwater snail Biomphalaria glabrata provided much new information, a disadvantage was that the hemoglobin molecules were not unequivocally defined in the electron microscope. This made it difficult to trace the exocytosis pathway of this protein. Therefore, we have now performed a similar study on the rhogocytes of the blue-blooded (hemocyanin-containing freshwater snail Lymnaea stagnalis. The intracellular hemocyanin could be identified in the electron microscope, either as individual molecules or as pseudo-crystalline arrays. Based on 3D-electron microscopy, and supplemented by in situ hybridization, immunocytochemistry and stress response experiments, we provide here additional details on the structure and hemocyanin biosynthesis of rhogocytes, and on their response in animals under cadmium and starvation stress. Moreover, we present an advanced model on the release of synthesized

  18. Sensory input from the osphradium modulates the response to memory-enhancing stressors in Lymnaea stagnalis.

    Science.gov (United States)

    Karnik, Vikram; Braun, Marvin; Dalesman, Sarah; Lukowiak, Ken

    2012-02-01

    In the freshwater environment species often rely on chemosensory information to modulate behavior. The pond snail, Lymnaea stagnalis, is a model species used to characterize the causal mechanisms of long-term memory (LTM) formation. Chemical stressors including crayfish kairomones and KCl enhance LTM formation (≥24 h) in Lymnaea; however, how these stressors are sensed and the mechanism by which they affect the electrophysiological properties of neurons necessary for memory formation are poorly understood. Here, we assessed whether the osphradium, a primary chemosensory organ in Lymnaea, modulates LTM enhancement. To test this we severed the osphradial nerve proximal to the osphradium, using sham-operated animals as controls, and assessed the behavioral and electrophysiological response to crayfish kairomones and KCl. We operantly conditioned aerial respiratory behavior in intact, sham and osphradially cut animals, and tested for enhanced memory formation after exposure to the chemical stressors. Sham-operated animals displayed the same memory enhancement as intact animals but snails with a severed osphradial nerve did not show LTM enhancement. Extracellular recordings made from the osphradial nerve demonstrate that these stressors evoked afferent sensory activity. Intracellular recordings from right pedal dorsal 1 (RPeD1), a neuron necessary for LTM formation, demonstrate that its electrophysiological activity is altered by input from the osphradium following exposure to crayfish kairomones or KCl in sham and intact animals but no response is seen in RPeD1 in osphradially cut animals. Therefore, sensory input from the osphradium is necessary for LTM enhancement following exposure to these chemical stressors.

  19. Silver nanoparticles alter learning and memory formation in an aquatic organism, Lymnaea stagnalis.

    Science.gov (United States)

    Young, Austin; Protheroe, Amy; Lukowiak, Ken

    2017-06-01

    We tested the effect of silver nanoparticles (AgNPs) on the ability of the pond snail, Lymnaea stagnalis, to learn and form long-term memory (LTM) following operant conditioning of aerial respiration. We hypothesized that the AgNPs would act as a stressor and prevent learning and LTM formation. We tested snails exposed for either 72 h or only during training and testing for memory (i.e. 0.5 h) and found no difference between those treatments. We found that at a low concentration of AgNPs (5 μg/L) neither learning and nor memory formation were altered. When we increased the concentration of AgNPs (10 μg/L) we found that memory formation was enhanced. Finally, at a higher concentration (50 μg/L) memory formation was blocked. To determine if the disassociation of Ag + from the AgNPs caused the effects on memory we performed similar experiments with AgNO 3 and found similar concentration-dependent results. Finally, we found that snails perceive the AgNPs differently from Ag+ as there was context specific memory. That is, snails trained in AgNPs did not show memory when tested in Ag + and vice-versa. We believe that changes in memory formation may be a more sensitive determination of AgNPs on aquatic organisms than the determination of a LC 50 . Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  20. Coordination of locomotor and cardiorespiratory networks of Lymnaea stagnalis by a pair of identified interneurones.

    Science.gov (United States)

    Syed, N I; Winlow, W

    1991-07-01

    1. The morphology and electrophysiology of a newly identified bilateral pair of interneurones in the central nervous system of the pulmonate pond snail Lymnaea stagnalis is described. 2. These interneurones, identified as left and right pedal dorsal 11 (L/RPeD11), are electrically coupled to each other as well as to a large number of foot and body wall motoneurones, forming a fast-acting neural network which coordinates the activities of foot and body wall muscles. 3. The left and right sides of the body wall of Lymnaea are innervated by left and right cerebral A cluster neurones. Although these motoneurones have only ipsilateral projections, they are indirectly electrically coupled to their contralateral homologues via their connections with L/RPeD11. Similarly, the activities of left and right pedal G cluster neurones, which are known to be involved in locomotion, are also coordinated by L/RPeD11. 4. Selective ablation of both neurones PeD11 results in the loss of coordination between the bilateral cerebral A clusters. 5. Interneurones L/RPeD11 are multifunctional. In addition to coordinating motoneuronal activity, they make chemical excitatory connections with heart motoneurones. They also synapse upon respiratory motoneurones, hyperpolarizing those involved in pneumostome opening (expiration) and depolarizing those involved in pneumostome closure (inspiration). 6. An identified respiratory interneurone involved in pneumostome closure (visceral dorsal 4) inhibits L/RPeD11 together with all their electrically coupled follower cells. 7. Both L/RPeD11 have strong excitatory effects on another pair of electrically coupled neurones, visceral dorsal 1 and right parietal dorsal 2, which have previously been shown to be sensitive to changes in the partial pressure of environmental oxygen (PO2). 8. Although L/RPeD11 participate in whole-body withdrawal responses, electrical stimulation applied directly to these neurones was not sufficient to induce this behaviour.

  1. Comparative and evaluation of anti-leech (Limnatis Nilotica effect of Olive (Olea Europaea L. with Levamisol and Tiabendazole

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    Majid Gholami-Ahangaran

    2012-05-01

    Full Text Available Objective: Until now, there is no registered drug for treatment of complications with leech in the world. According to the available scientific evidence, Olive is an effective anti-parasitic plant. Hence, in the present experiment we studied the inhibitory and killing effect of Olive methanolic extract on Limnatis nilotica. Methods: In this study, 100 leeches (Limnatis nilotica were collected from some wells in western area of Iran (south region in Ilam province and evaluated the antileech effects of Olive methanolic extract (Olea europaea L. in comparison with levamisole and tinidazole. Results: The results indicated no effect of tinidasole and distilled water on killing or mortality rate of the leeches but Olea europaea L. plant and levamisole have more effect on the L. nilotica. The mean death time of leech for levamisole and Olive determined 10依0.98 and 210依 24.1 minutes, respectively. Conclusions: The results showed that treatments of Olive methanolic extract and levamisole have the most effects on leeches and could be used as natural anti-L. nilotica. However it is necessary to achieve further studies for confirm of this subject.

  2. Reciprocal immune benefit based on complementary production of antibiotics by the leech Hirudo verbana and its gut symbiont Aeromonas veronii.

    Science.gov (United States)

    Tasiemski, Aurélie; Massol, François; Cuvillier-Hot, Virginie; Boidin-Wichlacz, Céline; Roger, Emmanuel; Rodet, Franck; Fournier, Isabelle; Thomas, Frédéric; Salzet, Michel

    2015-12-04

    The medicinal leech has established a long-term mutualistic association with Aeromonas veronii, a versatile bacterium which can also display free-living waterborne and fish- or human-pathogenic lifestyles. Here, we investigated the role of antibiotics in the dynamics of interaction between the leech and its gut symbiont Aeromonas. By combining biochemical and molecular approaches, we isolated and identified for the first time the antimicrobial peptides (AMPs) produced by the leech digestive tract and by its symbiont Aeromonas. Immunohistochemistry data and PCR analyses evidenced that leech AMP genes are induced in the gut epithelial cells when Aeromonas load is low (starved animals), while repressed when Aeromonas abundance is the highest (post blood feeding). The asynchronous production of AMPs by both partners suggests that these antibiotic substances (i) provide them with reciprocal protection against invasive bacteria and (ii) contribute to the unusual simplicity of the gut microflora of the leech. This immune benefit substantially reinforces the evidence of an evolutionarily stable association between H. verbana and A. veronii. Altogether these data may provide insights into the processes making the association with an Aeromonas species in the digestive tract either deleterious or beneficial.

  3. Polar localization of plasma membrane Ca2+/Mg2+ ATPase correlates with the pattern of steady ionic currents in eggs of Lymnaea stagnalis and Bithynia tentaculata (Mollusca)

    NARCIS (Netherlands)

    D. Zivkovic (Dana); R. Créton (Robbert); G. Zwaan (Gideon); W.C. de Bruijn (Wim); M.R. Dohmen (M.René)

    1990-01-01

    textabstractDuring extrusion of the first polar body in eggs of Lymnaea stagnalis and Bithynia tentaculata a localized Ca2+ /Mg2+ ATPase activity was detected, using Ando's enzyme-cytochemical method for electron microscopy [Ando et al. (1981) Acta Histochem Cytochem 14:705-726]. The enzyme activity

  4. A homologous form of human interleukin 16 is implicated in microglia recruitment following nervous system injury in leech Hirudo medicinalis.

    Science.gov (United States)

    Croq, Françoise; Vizioli, Jacopo; Tuzova, Marina; Tahtouh, Muriel; Sautiere, Pierre-Eric; Van Camp, Christelle; Salzet, Michel; Cruikshank, William W; Pestel, Joel; Lefebvre, Christophe

    2010-11-01

    In contrast to mammals, the medicinal leech Hirudo medicinalis can completely repair its central nervous system (CNS) after injury. This invertebrate model offers unique opportunities to study the molecular and cellular basis of the CNS repair processes. When the leech CNS is injured, microglial cells migrate and accumulate at the site of lesion, a phenomenon known to be essential for the usual sprouting of injured axons. In the present study, we demonstrate that a new molecule, designated HmIL-16, having functional homologies with human interleukin-16 (IL-16), has chemotactic activity on leech microglial cells as observed using a gradient of human IL-16. Preincubation of microglial cells either with an anti-human IL-16 antibody or with anti-HmIL-16 antibody significantly reduced microglia migration induced by leech-conditioned medium. Functional homology was demonstrated further by the ability of HmIL-16 to promote human CD4+ T cell migration which was inhibited by antibody against human IL-16, an IL-16 antagonist peptide or soluble CD4. Immunohistochemistry of leech CNS indicates that HmIL-16 protein present in the neurons is rapidly transported and stored along the axonal processes to promote the recruitment of microglial cells to the injured axons. To our knowledge, this is the first identification of a functional interleukin-16 homologue in invertebrate CNS. The ability of HmIL-16 to recruit microglial cells to sites of CNS injury suggests a role for HmIL-16 in the crosstalk between neurons and microglia in the leech CNS repair.

  5. Evidence for a novel chemotactic C1q domain-containing factor in the leech nerve cord.

    Science.gov (United States)

    Tahtouh, Muriel; Croq, Françoise; Vizioli, Jacopo; Sautiere, Pierre-Eric; Van Camp, Christelle; Salzet, Michel; Daha, Mohamed R; Pestel, Joël; Lefebvre, Christophe

    2009-02-01

    In vertebrates, central nervous system (CNS) protection is dependent on many immune cells including microglial cells. Indeed, activated microglial cells are involved in neuroinflammation mechanisms by interacting with numerous immune factors. Unlike vertebrates, some lophotrochozoan invertebrates can fully repair their CNS following injury. In the medicinal leech Hirudo medicinalis, the recruitment of microglial cells at the lesion site is essential for sprouting of injured axons. Interestingly, a new molecule homologous to vertebrate C1q was characterized in leech, named HmC1q (for H. medicinalis) and detected in neurons and glial cells. In chemotaxis assays, leech microglial cells were demonstrated to respond to human C1q. The chemotactic activity was reduced when microglia was preincubated with signaling pathway inhibitors (Pertussis Toxin or wortmannin) or anti-human gC1qR antibody suggesting the involvement of gC1qR in C1q-mediated migration in leech. Assays using cells preincubated with NO chelator (cPTIO) showed that C1q-mediated migration was associated to NO production. Of interest, by using anti-HmC1q antibodies, HmC1q released in the culture medium was shown to exhibit a similar chemotactic effect on microglial cells as human C1q. In summary, we have identified, for the first time, a molecule homologous to mammalian C1q in leech CNS. Its chemoattractant activity on microglia highlights a new investigation field leading to better understand leech CNS repair mechanisms.

  6. Occurrence of the Leech, Pontobdella muricata Linnaeus, on Elasmobranch Species in the Northern and Central Adriatic Sea.

    Science.gov (United States)

    Bolognini, Luca; Leoni, Simone; Polidori, Piero; Grati, Fabio; Scarcella, Giuseppe; Pellini, Giulio; Domenichetti, Filippo; Ferrà, Carmen; Fabi, Gianna

    2016-12-01

    This study provides a parasitological analysis of the elasmobranch species caught in the northern and central Adriatic Sea. Sixty-two marine leeches were recorded on 747 individuals of Raja clavata Linnaeus, 1758 (thornback ray), Myliobatis aquila Linnaeus, 1758 (common eagle ray), and Torpedo marmorata Risso, 1810 (marbled torpedo ray) caught in 56 hauls over a 5 yr period. All leeches were identified as Pontobdella muricata, which is a typical ectoparasite of benthic elasmobranchs. The prevalence of infection ranged from 7.11% on R. clavata to 12.00% on M. aquila. The intensity of infection, the preferential sites of attachment to the host, and the periodicity of infection were evaluated.

  7. A new glossiphoniid leech from Catemaco Lake, Veracruz, México.

    Science.gov (United States)

    Oceguera-Figueroa, Alejandro

    2008-04-01

    Haementeria acuecueyetzin n. sp. from Catemaco Lake, Veracruz, Mexico, is described based on the examination of 6 specimens. This new hematophagous leech species resembles other members of the genus in the number and position of the eyespots, number of compact salivary glands, and in the presence of 2 pairs of spheroidal mycetomes, but it is distinguished from the other species by having 6 rows of longitudinal smooth white papillae in the dorsal surface and numerous tubercles in dorsal and ventral surfaces. This new species represents the third species of Haementeria in the Northern Hemisphere of the Americas.

  8. Leech Therapy For The Treatment Of Venous Congestion In Flaps, Digital Re-Plants And Revascularizations - A Two-Year Review From A Regional Centre.

    Science.gov (United States)

    Butt, Ahsan Masood; Ismail, Amir; Lawson-Smith, Matthew; Shahid, Muhammad; Webb, Jill; Chester, Darren L

    2016-01-01

    Leeches are a well-recognized treatment for congested tissue. This study reviewed the efficacy of leech therapy for salvage of venous congested flaps and congested replanted or revascularized hand digits over a 2-year period. All patients treated with leeches between 1 Oct 2010 and 30 Sep 2012 (two years) at Queen Elizabeth Hospital, Birmingham, UK were included in the study. Details regarding mode of injury requiring reconstruction, surgical procedure, leech therapy duration, subsequent surgery requirement and tissue salvage rates were recorded. Twenty tissues in 18 patients required leeches for tissue congestion over 2 years: 13 men and 5 women. The mean patient age was 41 years (range 17-79). The defect requiring reconstruction was trauma in 16 cases, following tumour resection in two, and two miscellaneous causes. Thirteen cases had flap reconstruction and seven digits in six patients had hand digit replantations or revascularisation. Thirteen of 20 cases (65%) had successful tissue salvage following leech therapy for congestion (77% in 10 out of 13 flaps, and 43% in 3 of 7 digits). The rate of tissue salvage in pedicled flaps was good 6/6 (100%) and so was in digital revascularizations 2/3 (67%), but poor in digital re-plants 1/4 (25%) and free flaps 0/2 (0%). Leeches are a helpful tool for congested tissue salvage and in this study, showed a greater survival benefit for pedicled flaps than for free flaps or digital replantations.

  9. Genetic variation of Lymnaea stagnalis tolerance to copper: A test of selection hypotheses and its relevance for ecological risk assessment.

    Science.gov (United States)

    Côte, Jessica; Bouétard, Anthony; Pronost, Yannick; Besnard, Anne-Laure; Coke, Maïra; Piquet, Fabien; Caquet, Thierry; Coutellec, Marie-Agnès

    2015-10-01

    The use of standardized monospecific testing to assess the ecological risk of chemicals implicitly relies on the strong assumption that intraspecific variation in sensitivity is negligible or irrelevant in this context. In this study, we investigated genetic variation in copper sensitivity of the freshwater snail Lymnaea stagnalis, using lineages stemming from eight natural populations or strains found to be genetically differentiated at neutral markers. Copper-induced mortality varied widely among populations, as did the estimated daily death rate and time to 50% mortality (LT50). Population genetic divergence in copper sensitivity was compared to neutral differentiation using the QST-FST approach. No evidence for homogenizing selection could be detected. This result demonstrates that species-level extrapolations from single population studies are highly unreliable. The study provides a simple example of how evolutionary principles could be incorporated into ecotoxicity testing in order to refine ecological risk assessment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Correlated conductance parameters in leech heart motor neurons contribute to motor pattern formation.

    Science.gov (United States)

    Lamb, Damon G; Calabrese, Ronald L

    2013-01-01

    Neurons can have widely differing intrinsic membrane properties, in particular the density of specific conductances, but how these contribute to characteristic neuronal activity or pattern formation is not well understood. To explore the relationship between conductances, and in particular how they influence the activity of motor neurons in the well characterized leech heartbeat system, we developed a new multi-compartmental Hodgkin-Huxley style leech heart motor neuron model. To do so, we evolved a population of model instances, which differed in the density of specific conductances, capable of achieving specific output activity targets given an associated input pattern. We then examined the sensitivity of measures of output activity to conductances and how the model instances responded to hyperpolarizing current injections. We found that the strengths of many conductances, including those with differing dynamics, had strong partial correlations and that these relationships appeared to be linked by their influence on heart motor neuron activity. Conductances that had positive correlations opposed one another and had the opposite effects on activity metrics when perturbed whereas conductances that had negative correlations could compensate for one another and had similar effects on activity metrics.

  11. The effect of ammonium chloride concentrationson the content of carotenoid pigments in the body of Lymnaea stagnalis

    Directory of Open Access Journals (Sweden)

    G. E. Kyrychuk

    2015-09-01

    Full Text Available The paper deals with the peculiarities of distribution of β-carotene and xanthophylls in the body of Lymnaea stagnalis (Linnaeus, 1758 (Pulmonata, Lymnaeidae in the normal conditions and under the action of different concentrations of NH4Cl, depending on duration of exposure (2, 7, 14 and 21 days. L. stagnalis (300 copies were collected in September 2013–2014 (in Zhytomyr region. Toxicant NH4Cl was used in concentrations corresponding to 0.5, 2, 5 and 10 MAC. The content of β-carotene and xanthophylls was determined by the Taylor method. 2400 biochemical analyses were carried out. The article shows that under the action of 0.5 MPC NH4Cl adaptive processes are stimulated in the body of L. stagnalis and total antioxidant activity is activated, as evidenced by changes in the content of β-carotene and xanthophylls in the organs (hepatopancreas, pallium and foot and tissues (hemolymph of the mollusks under study. The research proves that the action of concentration discussed above during 2, 14 and 21 days causes the increase in the content of β-carotene in hepatopancreas (1.63–5.73 times, pallium (1.68–5.37 times and foot (1.81–3.89 times of animals. Incubation of mollusks in solutions of NH4Cl (0.5 MAC for 7 days resulted in the decrease of figures in these organs by 23,6–38,8% relatively to control. It should be noted that from the overall dynamics hemolymph is somewhat distracting; for it 1.35–1.46 times’ decrease in the content of β-carotene after short-term action of the toxicant (2 and 7 days and β-carotene increase by 2.79–7.38 times under conditions of prolonged exposure (14 and 21 days is recorded. The content of xanthophylls correlates with the content of β-carotene on the 2nd, 7th and 14th day of toxic action, but by increasing the time of contact with toxic substances to 21 days the decrease in figures by 20,9–40,7% in foot and pallium is recorded. When the toxicant concentration is increased to 2 MAC (with 2

  12. Rediscovery of two rare butterflies Papilio elephenor Doubleday, 1845 and Shijimia moorei Leech, 1889 from proposed Ripu-Chirang Wildlife Sanctuary, Assam, India

    Directory of Open Access Journals (Sweden)

    K. Choudhury

    2010-04-01

    Full Text Available Two rare butterflies Papilio elephenor Doubleday, 1886 and Moore’s Cupid Shijimia moorei Leech, 1889 were rediscovered from the proposed Ripu-Chirang Wildlife Sanctuary, Assam, India.

  13. Larval trematodes (Digenea) of the great pond snail, Lymnaea stagnalis (L.), (Gastropoda, Pulmonata) in Central Europe: a survey of species and key to their identification

    Czech Academy of Sciences Publication Activity Database

    Faltýnková, Anna; Našincová, Vanda; Kablásková, Lenka

    2007-01-01

    Roč. 14, č. 1 (2007), s. 39-51 ISSN 1252-607X R&D Projects: GA AV ČR IAA6022404; GA ČR GP524/07/P086; GA ČR GD524/03/H133; GA MŠk LC522 Institutional research plan: CEZ:AV0Z60220518 Keywords : Trematoda * Mollusca * cercaria * metacercaria * Lymnaea stagnalis Subject RIV: EG - Zoology Impact factor: 0.713, year: 2007

  14. From the Worm in a Bottle of Mezcal: iDNA Confirmation of a Leech Parasitizing the Antillean Manatee.

    Science.gov (United States)

    Pérez-Flores, J; Rueda-Calderon, H; Kvist, S; Siddall, M E; Oceguera-Figueroa, A

    2016-10-01

    Invertebrate-derived ingested DNA (iDNA) is quickly proving to be a valuable, non-invasive tool for monitoring vertebrate species of conservation concern. Using the DNA barcoding locus, we successfully identified both the blood-feeding leech Haementeria acuecueyetzin and its blood meal-the latter is shown to be derived from the Caribbean manatee, Trichechus manatus . DNA amplification was successful despite the fact that the specimen was fixed in Mezcal (a beverage distilled from agave). We report the first confirmed case of a leech feeding on a manatee, the first record of H. acuecueyetzin for the State of Chiapas and, to our knowledge, the first case of successful DNA amplification of a biological sample fixed in Mezcal other than the caterpillar "worms" more commonly found in that beverage.

  15. The use of medicinal leeches in fingertip replantation without venous anastomosis - case report of a 4-year-old patient.

    Science.gov (United States)

    Streit, L; Dvořák, Z; Novák, O; Stiborová, S; Veselý, J

    2014-01-01

    Replantation of amputated fingertip is a technical challenge to the microsurgeons. The success rate depends directly on the availability and the size of preserved vessels and on the degree of their damage. In distal digital amputations, veins are usually not easily recovered or even absent, and thus high number of replantation procedures fails because of the venous congestion. The use of medicinal leeches is a treatment option for venous congestion of replanted fingers. A case report of a 4-year-old patient after fingertip replantation without venous anastomosis when temporary venous drainage was provided by an application of medicinal leeches is reported together with literature review. We observed an unusually short duration of venous congestion (48 hours) and there was no need of blood transfusion.

  16. Modelling effects of diquat under realistic exposure patterns in genetically differentiated populations of the gastropod Lymnaea stagnalis.

    Science.gov (United States)

    Ducrot, Virginie; Péry, Alexandre R R; Lagadic, Laurent

    2010-11-12

    Pesticide use leads to complex exposure and response patterns in non-target aquatic species, so that the analysis of data from standard toxicity tests may result in unrealistic risk forecasts. Developing models that are able to capture such complexity from toxicity test data is thus a crucial issue for pesticide risk assessment. In this study, freshwater snails from two genetically differentiated populations of Lymnaea stagnalis were exposed to repeated acute applications of environmentally realistic concentrations of the herbicide diquat, from the embryo to the adult stage. Hatching rate, embryonic development duration, juvenile mortality, feeding rate and age at first spawning were investigated during both exposure and recovery periods. Effects of diquat on mortality were analysed using a threshold hazard model accounting for time-varying herbicide concentrations. All endpoints were significantly impaired at diquat environmental concentrations in both populations. Snail evolutionary history had no significant impact on their sensitivity and responsiveness to diquat, whereas food acted as a modulating factor of toxicant-induced mortality. The time course of effects was adequately described by the model, which thus appears suitable to analyse long-term effects of complex exposure patterns based upon full life cycle experiment data. Obtained model outputs (e.g. no-effect concentrations) could be directly used for chemical risk assessment.

  17. Does water chemistry affect the dietary uptake and toxicity of silver nanoparticles by the freshwater snail Lymnaea stagnalis?

    Science.gov (United States)

    López-Serrano Oliver, Ana; Croteau, Marie-Noële; Stoiber, Tasha L.; Tejamaya, Mila; Römer, Isabella; Lead, Jamie R.; Luoma, Samuel N.

    2014-01-01

    Silver nanoparticles (AgNPs) are widely used in many applications and likely released into the aquatic environment. There is increasing evidence that Ag is efficiently delivered to aquatic organisms from AgNPs after aqueous and dietary exposures. Accumulation of AgNPs through the diet can damage digestion and adversely affect growth. It is well recognized that aspects of water quality, such as hardness, affect the bioavailability and toxicity of waterborne Ag. However, the influence of water chemistry on the bioavailability and toxicity of dietborne AgNPs to aquatic invertebrates is largely unknown. Here we characterize for the first time the effects of water hardness and humic acids on the bioaccumulation and toxicity of AgNPs coated with polyvinyl pyrrolidone (PVP) to the freshwater snail Lymnaea stagnalis after dietary exposures. Our results indicate that bioaccumulation and toxicity of Ag from PVP-AgNPs ingested with food are not affected by water hardness and by humic acids, although both could affect interactions with the biological membrane and trigger nanoparticle transformations. Snails efficiently assimilated Ag from the PVP-AgNPs mixed with diatoms (Ag assimilation efficiencies ranged from 82 to 93%). Rate constants of Ag uptake from food were similar across the entire range of water hardness and humic acid concentrations. These results suggest that correcting regulations for water quality could be irrelevant and ineffective where dietary exposure is important.

  18. Metabolomics to Explore Imidacloprid-Induced Toxicity in the Central Nervous System of the Freshwater Snail Lymnaea stagnalis.

    Science.gov (United States)

    Tufi, Sara; Stel, Jente M; de Boer, Jacob; Lamoree, Marja H; Leonards, Pim E G

    2015-12-15

    Modern toxicology is seeking new testing methods to better understand toxicological effects. One of the most concerning chemicals is the neonicotinoid pesticide imidacloprid. Although imidacloprid is designed to target insects, recent studies have shown adverse effects on nontarget species. Metabolomics was applied to investigate imidacloprid-induced sublethal toxicity in the central nervous system of the freshwater snail Lymnaea stagnalis. The snails (n = 10 snails) were exposed for 10 days to increasing imidacloprid concentrations (0.1, 1, 10, and 100 μg/L). The comparison between control and exposure groups highlighted the involvement and perturbation of many biological pathways. The levels of several metabolites belonging to different metabolite classes were significantly changed by imidacloprid exposure. A change in the amino acids and nucleotide metabolites like tryptophan, proline, phenylalanine, uridine, and guanosine was found. Many fatty acids were down-regulated, and the levels of the polyamines, spermidine and putrescine, were found to be increased which is an indication of neuron cell injury. A turnover increase between choline and acetylcholine led us to hypothesize an increase in cholinergic gene expression to overcome imidacloprid binding to the nicotinic acetylcholine receptors. Metabolomics revealed imidacloprid induced metabolic changes at low and environmentally relevant concentration in a nontarget species and generated a novel mechanistic hypothesis.

  19. Metallothionein and glutathione in Lymnaea stagnalis determine the specificity of responses to the effects of ionising radiation

    International Nuclear Information System (INIS)

    Gnatyshyna, L.; Falfushynska, H.; Stoliar, O.; Bodilovska, O.; Oleynik, O.; Golubev, A.

    2012-01-01

    The aim of our study was to distinguish the stress-related molecular response of the pulmonate mollusc Lymnaea stagnalis from the Chernobyl area in comparison with the consequences of other harmful effects, including the short-term effects of radiation and heating. Specimens inhabiting ponds near the Chernobyl nuclear power plant, the cooling channel of the electric power station and the soil reclamation channel (groups R, T and C, correspondingly), and specimens adapted to laboratory conditions (a control group (CL), a disposable group exposed to 2 mGy X-ray radiation over the body (RL), and a group exposed to 25 deg. C for 4 days (TL)) were compared. Despite high variability of responses, Principle Component Analysis distinctly separated the laboratory and feral groups into two sets. In the feral groups, low levels of the stress-related and metal-binding protein metallothionein (MT), protein carbonyls and lactate dehydrogenase in the digestive gland were indicated. The main separating criteria selected by classification and regression tree analysis were the protein carbonyls, cholinesterase and MT. Molluscs from group R were clearly distinguished by the lowest levels of MT, Mn-superoxide dismutase and lactate dehydrogenase, and the highest level of glutathione, demonstrating that the oppression of the gene-determined stress-related response and its partially metabolic compensation can be possible markers for chronic environmental effects of irradiation. (authors)

  20. leech infestation

    African Journals Online (AJOL)

    GB

    2013-03-01

    Mar 1, 2013 ... fish, amphibians, and mammals. Infestation occurs by drinking infested water from quiet streams, pools and springs. They attach to their hosts ... trauma, foreign body ingestion, throat pain, fever, dysphagia and drug intake. He has no malena, haematuria, epistaxis or ecchymotic spots on the body. He had ...

  1. Conversion of recombinant hirudin to the natural form by in vitro tyrosine sulfation. Differential substrate specificities of leech and bovine tyrosylprotein sulfotransferases.

    Science.gov (United States)

    Niehrs, C; Huttner, W B; Carvallo, D; Degryse, E

    1990-06-05

    Hirudin, a tyrosine-sulfated protein secreted by the leech Hirudo medicinalis, is one of the most potent anticoagulants known. The hirudin cDNA has previously been cloned and has been expressed in yeast, but the resulting recombinant protein was found to be produced in the unsulfated form, which is known to have an at least 10 times lower affinity for thrombin than the naturally occurring tyrosine-sulfated hirudin. Here we describe the in vitro tyrosine sulfation of recombinant hirudin by leech and bovine tyrosylprotein sulfotransferase (TPST). With both enzymes, in vitro sulfation of recombinant hirudin occurred at the physiological site (Tyr-63) and rendered the protein biochemically and biologically indistinguishable from natural hirudin. However, leech TPST had an over 20-fold lower apparent Km value for recombinant hirudin than bovine TPST. Further differences in the catalytic properties of leech and bovine TPSTs were observed when synthetic peptides were tested as substrates. Moreover, a synthetic peptide corresponding to the 9 carboxyl-terminal residues of hirudin (which include Tyr-63) was sulfated by leech TPST with a similar apparent Km value as full length hirudin, indicating that structural determinants residing in the immediate vicinity of Tyr-63 are sufficient for sulfation to occur.

  2. Development of partial life-cycle experiments to assess the effects of endocrine disruptors on the freshwater gastropod Lymnaea stagnalis: a case-study with vinclozolin.

    Science.gov (United States)

    Ducrot, Virginie; Teixeira-Alves, Mickaël; Lopes, Christelle; Delignette-Muller, Marie-Laure; Charles, Sandrine; Lagadic, Laurent

    2010-10-01

    Long-term effects of endocrine disruptors (EDs) on aquatic invertebrates remain difficult to assess, mainly due to the lack of appropriate sensitive toxicity test methods and relevant data analysis procedures. This study aimed at identifying windows of sensitivity to EDs along the life-cycle of the freshwater snail Lymnaea stagnalis, a candidate species for the development of forthcoming test guidelines. Juveniles, sub-adults, young adults and adults were exposed for 21 days to the fungicide vinclozolin (VZ). Survival, growth, onset of reproduction, fertility and fecundity were monitored weekly. Data were analyzed using standard statistical analysis procedures and mixed-effect models. No deleterious effect on survival and growth occurred in snails exposed to VZ at environmentally relevant concentrations. A significant impairment of the male function occurred in young adults, leading to infertility at concentrations exceeding 0.025 μg/L. Furthermore, fecundity was impaired in adults exposed to concentrations exceeding 25 μg/L. Biological responses depended on VZ concentration, exposure duration and on their interaction, leading to complex response patterns. The use of a standard statistical approach to analyze those data led to underestimation of VZ effects on reproduction, whereas effects could reliably be analyzed by mixed-effect models. L. stagnalis may be among the most sensitive invertebrate species to VZ, a 21-day reproduction test allowing the detection of deleterious effects at environmentally relevant concentrations of the fungicide. These results thus reinforce the relevance of L. stagnalis as a good candidate species for the development of guidelines devoted to the risk assessment of EDs.

  3. Polar localization of plasma membrane Ca2+/Mg2+ ATPase correlates with the pattern of steady ionic currents in eggs of Lymnaea stagnalis and Bithynia tentaculata (Mollusca)

    OpenAIRE

    Zivkovic, Dana; Créton, Robbert; Zwaan, Gideon; Bruijn, Wim; Dohmen, M.René

    1990-01-01

    textabstractDuring extrusion of the first polar body in eggs of Lymnaea stagnalis and Bithynia tentaculata a localized Ca2+ /Mg2+ ATPase activity was detected, using Ando's enzyme-cytochemical method for electron microscopy [Ando et al. (1981) Acta Histochem Cytochem 14:705-726]. The enzyme activity was distributed in a polar fashion, along the cytoplasmic face of the plasma membrane. In the eggs of Lymnaea it was found only in the vegetal hemisphere, whereas in Bithynia eggs it was localized...

  4. The bioavailability of the transuranic elements 237Pu and 241Am for the pond snail, Lymnaea stagnalis L., and their behaviour in selected natural surface waters

    International Nuclear Information System (INIS)

    Thiels, G.M.

    1983-01-01

    An attempt was made to characterise the bioavailability of 237 Pu and 241 Am for the pond snail Lymnaea stagnalis L. in selected surface waters. The uptake, distribution and retention patterns were studied through the contamination route water-snail. The effects of a number of parameters, such as seasonal variation, water type (pH, conductivity, ionic composition) and presence of food, on the bioavailability of the transuranics were evaluated. Finally, an assessment was made concerning the chemical speciation of plutonium and americium in the selected freshwaters

  5. The Ozobranchus leech is a candidate mechanical vector for the fibropapilloma-associated turtle herpesvirus found latently infecting skin tumors on Hawaiian green turtles (Chelonia mydas)

    International Nuclear Information System (INIS)

    Greenblatt, Rebecca J.; Work, Thierry M.; Balazs, George H.; Sutton, Claudia A.; Casey, Rufina N.; Casey, James W.

    2004-01-01

    Fibropapillomatosis (FP) of marine turtles is a neoplastic disease of ecological concern. A fibropapilloma-associated turtle herpesvirus (FPTHV) is consistently present, usually at loads exceeding one virus copy per tumor cell. DNA from an array of parasites of green turtles (Chelonia mydas) was examined with quantitative PCR (qPCR) to determine whether any carried viral loads are sufficient to implicate them as vectors for FPTHV. Marine leeches (Ozobranchus spp.) were found to carry high viral DNA loads; some samples approached 10 million copies per leech. Isopycnic sucrose density gradient/qPCR analysis confirmed that some of these copies were associated with particles of the density of enveloped viruses. The data implicate the marine leech Ozobranchus as a mechanical vector for FPTHV. Quantitative RT-PCR analysis of FPTHV gene expression indicated that most of the FPTHV copies in a fibropapilloma have restricted DNA polymerase expression, suggestive of latent infection

  6. Clinical report of still-birth in a goat due to leech infestation

    Directory of Open Access Journals (Sweden)

    Y Gharedaghi

    2010-08-01

    At autumn 2009 a four year old pregnant white indigenous female goat was referred to the veterinary clinic located in Sarab. At initial examinations clinical symptoms such as cachexia, sever pains of parturition, rest less and provocation was seen and as the result of these sever pains tachycardia, tachy pnea, teeth grinding and grades of anemia was seen at mucous membranes and the animal could not stand. The fetus had entered the pelvic canal with flexion of the metacarpus and following correction of this position, it was extracted manually. The newly born kid had anasarcus and generalized edema in the forelimbs, hindlimbs and skull. During manual extraction of the fetus, 20 worms about 10–12 cm in length were discharged from the goats vagina. Isolated parasitic samples from the animal were fixed in %10 formalin and were referred to the parasitological laboratory of veterinary faculty of Islamic Azad university- Tabriz Branch. After further examinations they were identified as limnatis nilotica leeches. The kid goat died hours after birth because of respiratory difficulties.

  7. [Leeches, phytotherapy and physiotherapy in osteo-arthrosis of the knee--a geriatric case study].

    Science.gov (United States)

    Teut, Michael; Warning, Albrecht

    2008-10-01

    Chronic pain is a serious problem for geriatric patients. Conventional pharmacotherapy with nonsteroidal anti-inflammatory drugs or opiates is often accompanied by serious side effects. An 87-year-old woman with severe joint pain due to osteoarthritis of the knee presented with side effects from fentanyl therapy. She was subsequently treated in an inpatient setting with leeches, phytotherapy, physiotherapy and three single doses of metamizol. Prospective single-case study. Pain reduction was assessed with a numeric rating scale (0-10; 0 = minimum; 10 = maximum), mobility by walking distance, and activities of daily living by Barthel index. The association between complementary therapy and the changes observed in the patient under treatment were evaluated using cognition-based medicine. Under complementary therapy, the patient experienced a clear reduction in pain (from 8 to 3 points on the numeric rating scale); regained the ability to walk (increase in walking distance from 0 to 70 m); and showed improvements in activities of daily living (increase in Barthel index from 45 to 65). An association between pain reduction and the complementary treatment setting seems likely. The role of complementary pain therapy in geriatric patients should be evaluated systematically. 2008 S. Karger AG, Basel

  8. Aptitude of Lymnaea palustris and L. stagnalis to Fasciola hepatica larval development through the infection of several successive generations of 4-mm-high snails.

    Science.gov (United States)

    Vignoles, P; Rondelaud, D; Dreyfuss, G

    2016-06-01

    Bimiracidial infections of Lymnaea palustris and Lymnaea stagnalis (shell height at exposure, 4 mm) with Fasciola hepatica were carried out during six successive snail generations to determine if prevalence and intensity of snail infection increased over time through descendants issuing from eggs laid by parents already exposed to this digenean. Controls were constituted by a French population of Galba truncatula (a single generation) infected according to the same protocol. In a first experiment performed with the F1 to F5 generations of L. palustris, the prevalence and intensity of F. hepatica infection in snails progressively increased. Immature rediae and a few cercariae-containing rediae of the digenean were observed in L. stagnalis from the F3 generation, but no free cercaria was noted in the bodies of this lymnaeid from the F4 to F6 generations. In another experiment carried out with the F6 generation of L. palustris, the prevalence of F. hepatica infection and the number of shed cercariae were significantly lower in L. palustris than in G. truncatula. This mode of snail infection suggests an explanation for cases of human fasciolosis occurring in central France after the collection of wild watercress from beds where L. palustris was the sole lymnaeid.

  9. Larval trematodes (Digenea of the great pond snail, Lymnaea stagnalis (L., (Gastropoda, Pulmonata in Central Europe: a survey of species and key to their identification

    Directory of Open Access Journals (Sweden)

    Faltýnková A.

    2007-03-01

    Full Text Available A survey of cercariae and metacercariae (Trematoda, Digenea from the great pond snail (Lymnaea stagnalis in Central Europe (Austria, Czech Republic, South-East Germany, Poland and Slovak Republic is presented, based on a study of 3,628 snails examined from 1998 to 2005. A total of 953 (26.3% L. stagnalis were infected with 24 trematode species comprising 19 species of cercariae and 11 species of metacercariae (six species occurred both as cercarie and metacercarie of eight families. The dominant cercariae were those of Opisthioglyphe ranae (159 hosts infected, Plagiorchis elegans (141 (both family Plagiorchiidae and Echinoparyphium aconiatum (153 (Echinostomatidae; 14 double infections were found. The most frequent metacercariae were those of Neoglyphe locellus (71 (Omphalometridae, E. aconiatum (66, Echinostoma sp. (59 and Moliniella anceps (48 (Echinostomatidae. In the previous studies carried out in Central Europe, a very similar spectrum of nine trematode families of 22 cercariae determined to species level and 43 types of cercariae reported under generic or provisional names, which can be in many cases conspecific with the previous taxa, were found. A simple key to identification of cercariae and metacercariae, together with their illustrations, is provided.

  10. Effect of low potassium concentration on cadmium induced epileptiform activity of leech retzius neurons

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    Milićević Nebojša

    2016-01-01

    Full Text Available Epilepsies have a large significance and require detailed investigation of cellular mechanisms that lead to this disorder. Environmental, especially industrial, toxins are having increasingly more prominent role in these investigations. The aim of our research was to investigate the significance of Cd2+ in generation of epileptiform electrical activity of neurons, and the role of Na+/K+ pump in mechanisms that lead to cessation of this activity. Experiments were performed on Retzius nerve cells of the leech Haemopis sanguisuga. Intracellularly placed microelectrodes were used to measure membrane potential changes upon administration of Cd2+ (100 µmol/l, and the same concentration of Cd2+ in low K+ (1 mmol/l solution. In our experiments Cd2+ led to generation of rhythmic repetitive oscillatory activity. This activity closely resembles paroxysmal depolarizing shifts (PDS which represent the cellular basis of epilepsy. Cd2+ induced epileptiform activity had the following characteristics: frequency of 3.9±0.8 PDS/minute, PDS duration of 4.0±0.3 s, and PDS amplitude of 8.1±0.7 mV. Cd2+ induces effects similar to those of Ni2+ and Co2+, but in 30 times smaller concentration. Application of Cd2+ in low K+ solution led to a significant reduction of PDS frequency (by 2.34±0.55 PDS/minute, p<0.05, Student's t-test, highly significant increase in PDS duration (by 2.84±0.23 s, p<0.01, Student's t-test and highly significant reduction in PDS amplitude (by 1.91±0.33 mV, p=0.01, Student's t-test. Our results show that Cd2+ is a potent initiator of epileptiform activity, and that Na+/K+ pump significantly affects this activity and has a potentially important role in mechanisms that lead to its cessation.

  11. Propensity for Bistability of Bursting and Silence in the Leech Heart Interneuron

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    Tatiana Dashevskiy

    2018-02-01

    Full Text Available The coexistence of neuronal activity regimes has been reported under normal and pathological conditions. Such multistability could enhance the flexibility of the nervous system and has many implications for motor control, memory, and decision making. Multistability is commonly promoted by neuromodulation targeting specific membrane ionic currents. Here, we investigated how modulation of different ionic currents could affect the neuronal propensity for bistability. We considered a leech heart interneuron model. It exhibits bistability of bursting and silence in a narrow range of the leak current parameters, conductance (gleak and reversal potential (Eleak. We assessed the propensity for bistability of the model by using bifurcation diagrams. On the diagram (gleak, Eleak, we mapped bursting and silent regimes. For the canonical value of Eleak we determined the range of gleak which supported the bistability. We use this range as an index of propensity for bistability. We investigated how this index was affected by alterations of ionic currents. We systematically changed their conductances, one at a time, and built corresponding bifurcation diagrams in parameter planes of the maximal conductance of a given current and the leak conductance. We found that conductance of only one current substantially affected the index of propensity; the increase of the maximal conductance of the hyperpolarization-activated cationic current increased the propensity index. The second conductance with the strongest effect was the conductance of the low-threshold fast Ca2+ current; its reduction increased the propensity index although the effect was about two times smaller in magnitude. Analyzing the model with both changes applied simultaneously, we found that the diagram (gleak, Eleak showed a progressively expanded area of bistability of bursting and silence.

  12. Development and validation of an OECD reproductive toxicity test guideline with the pond snail Lymnaea stagnalis (Mollusca, Gastropoda).

    Science.gov (United States)

    Ducrot, Virginie; Askem, Clare; Azam, Didier; Brettschneider, Denise; Brown, Rebecca; Charles, Sandrine; Coke, Maïra; Collinet, Marc; Delignette-Muller, Marie-Laure; Forfait-Dubuc, Carole; Holbech, Henrik; Hutchinson, Thomas; Jach, Arne; Kinnberg, Karin L; Lacoste, Cédric; Le Page, Gareth; Matthiessen, Peter; Oehlmann, Jörg; Rice, Lynsey; Roberts, Edward; Ruppert, Katharina; Davis, Jessica Elphinstone; Veauvy, Clemence; Weltje, Lennart; Wortham, Ruth; Lagadic, Laurent

    2014-12-01

    The OECD test guideline development program has been extended in 2011 to establish a partial life-cycle protocol for assessing the reproductive toxicity of chemicals to several mollusk species, including the great pond snail Lymnaea stagnalis. In this paper, we summarize the standard draft protocol for a reproduction test with this species, and present inter-comparison results obtained in a 56-day prevalidation ring-test using this protocol. Seven European laboratories performed semi-static tests with cultured snails of the strain Renilys® exposed to nominal concentrations of cadmium chloride (from 53 to 608μgCdL(-1)). Cd concentrations in test solutions were analytically determined to confirm accuracy in the metal exposure concentrations in all laboratories. Physico-chemical and biological validity criteria (namely dissolved oxygen content >60% ASV, water temperature 20±1°C, control snail survival >80% and control snail fecundity >8 egg-masses per snail over the test period) were met in all laboratories which consistently demonstrated the reproductive toxicity of Cd in snails using the proposed draft protocol. Effect concentrations for fecundity after 56days were reproducible between laboratories (68

  13. The efficacy and safety of medical leech therapy for osteoarthritis of the knee: A meta-analysis of randomized controlled trials.

    Science.gov (United States)

    Wang, Haixia; Zhang, Jing; Chen, Liyan

    2018-06-01

    It is controversial on whether medical leech therapy is effective in improving pain and functional outcome in patients with knee osteoarthritis (OA). Therefore, we perform a meta-analysis from randomized controlled trials (RCTs) to evaluate the efficacy and safety of medical leech therapy in patients with knee OA. The PubMed, EMBASE, ScienceDirect, and Cochrane Library databases were systematically searched for literature up to January 2018. RCTs involving medical leech therapy in patients with knee OA were included. Two independent reviewers performed independent data abstraction. The I 2 statistic was used to assess heterogeneity. A fixed or random effects model was adopted for meta-analysis. All meta-analyses were performed by using STATA 12.0. Four RCTs with 264 patients were included in this meta-analysis. The current meta-analysis showed that there were significant differences in terms of visual analogue scale (VAS) scores and WOMAC scores at 1 week, 4weeks and 7 weeks compared with control groups. However, leech therapy was associated with a significantly higher incidence of adverse events. The overall evidence quality is moderate, which means that further research is likely to significantly change confidence in the effect estimate but may change the estimate. Medical leech therapy was associated with a significantly improved outcome in pain relief and functional recovery in patients with symptomatic knee OA. However, given the inherent limitations in the included studies, this conclusion should be interpreted cautiously. Copyright © 2018 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

  14. Accumulation and detoxication responses of the gastropod Lymnaea stagnalis to single and combined exposures to natural (cyanobacteria) and anthropogenic (the herbicide RoundUp(®) Flash) stressors.

    Science.gov (United States)

    Lance, Emilie; Desprat, Julia; Holbech, Bente Frost; Gérard, Claudia; Bormans, Myriam; Lawton, Linda A; Edwards, Christine; Wiegand, Claudia

    2016-08-01

    Freshwater gastropods are increasingly exposed to multiple stressors in the field such as the herbicide glyphosate in Roundup formulations and cyanobacterial blooms either producing or not producing microcystins (MCs), potentially leading to interacting effects. Here, the responses of Lymnaea stagnalis to a 21-day exposure to non-MC or MC-producing (33μgL(-1)) Planktothrix agardhii alone or in combination with the commercial formulation RoundUp(®) Flash at a concentration of 1μgL(-1) glyphosate, followed by 14days of depuration, were studied via i) accumulation of free and bound MCs in tissues, and ii) activities of anti-oxidant (catalase CAT) and biotransformation (glutathione-S-transferase GST) enzymes. During the intoxication, the cyanobacterial exposure induced an early increase of CAT activity, independently of the MC content, probably related to the production of secondary cyanobacterial metabolites. The GST activity was induced by RoundUp(®) Flash alone or in combination with non MC-producing cyanobacteria, but was inhibited by MC-producing cyanobacteria with or without RoundUp(®) Flash. Moreover, MC accumulation in L. stagnalis was 3.2 times increased when snails were concomitantly exposed to MC-producing cyanobacteria with RoundUp(®), suggesting interacting effects of MCs on biotransformation processes. The potent inhibition of detoxication systems by MCs and RoundUp(®) Flash was reversible during the depuration, during which CAT and GST activities were significantly higher in snails previously exposed to MC-producing cyanobacteria with or without RoundUp(®) Flash than in other conditions, probably related to the oxidative stress caused by accumulated MCs remaining in tissues. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. RELIABILITY OF BARR, LEECH, AND BLETHYN SCORE IN USING OF PLAIN RADIOGRAPHY IN DETERMINING FECAL IMPACTION IN CHILDREN WITH AND WITHOUT CONSTIPATION

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    Afshin REZAZADEH

    Full Text Available ABSTRACT Background - Several scoring was developed for evaluation of children with fecal retention using plain radiograph. There are controversies about specificity and sensitivity of these scoring system. Objectives - The aim of this study was to evaluate Barr, Blethyn, and Leech score in evaluation of fecal load in plain radiograph. Methods - This case control study was conducted on children aged 2-14 years old with abdominal pain who visited Abuzar children's Hospital of Ahvaz University of Medical Sciences. This study was conducted in fall season. Children with history of previous abdominal surgery, any systemic illness including sickle cell anemia were excluded. Children with constipation were placed in case group. Subjects without constipation were placed in control group. Subjects without exclusion criteria were examined by physician who is blind to aim of the study. Careful history and physical examination was done. Demographic features, history of gastrointestinal problem, duration of abdominal pain, defecation habit, stool consistency (loose, hard, and results of physical examination were recorded. Rome III criteria was used for definition of constipation. Abdominal x-ray was ordered for each patients. Abdominal radiography was reviewed by radiologist. Barr, Leach, and Blethyn scores were calculated for each case. Results - In this study 102 children with functional constipation and 102 children without constipation as a control were included. Mean ±SD for case and control group was 68.39±34.88 and 69.46±32.60 (P=0.82.Leech score (mean ±SD was 11.05±2.177 and 5.67±3.228 for case and control group respectively (P<0.0001. Barr score (mean ±SD was 14.86±3.54 and 7.16±5.59 for case and control group respectively (P=<0.0001. Blethyn (mean ±SD score was 1.97±0.667 and 1.04±0.900 for case and control group respectively (P=0.000. Sensitivity and specificity of Barr score was 83% and 79% respectively. Sensitivity and specificity of

  16. Interaction of HmC1q with leech microglial cells: involvement of C1qBP-related molecule in the induction of cell chemotaxis

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    Tahtouh Muriel

    2012-02-01

    Full Text Available Abstract Background In invertebrates, the medicinal leech is considered to be an interesting and appropriate model to study neuroimmune mechanisms. Indeed, this non-vertebrate animal can restore normal function of its central nervous system (CNS after injury. Microglia accumulation at the damage site has been shown to be required for axon sprouting and for efficient regeneration. We characterized HmC1q as a novel chemotactic factor for leech microglial cell recruitment. In mammals, a C1q-binding protein (C1qBP alias gC1qR, which interacts with the globular head of C1q, has been reported to participate in C1q-mediated chemotaxis of blood immune cells. In this study, we evaluated the chemotactic activities of a recombinant form of HmC1q and its interaction with a newly characterized leech C1qBP that acts as its potential ligand. Methods Recombinant HmC1q (rHmC1q was produced in the yeast Pichia pastoris. Chemotaxis assays were performed to investigate rHmC1q-dependent microglia migration. The involvement of a C1qBP-related molecule in this chemotaxis mechanism was assessed by flow cytometry and with affinity purification experiments. The cellular localization of C1qBP mRNA and protein in leech was investigated using immunohistochemistry and in situ hybridization techniques. Results rHmC1q-stimulated microglia migrate in a dose-dependent manner. This rHmC1q-induced chemotaxis was reduced when cells were preincubated with either anti-HmC1q or anti-human C1qBP antibodies. A C1qBP-related molecule was characterized in leech microglia. Conclusions A previous study showed that recruitment of microglia is observed after HmC1q release at the cut end of axons. Here, we demonstrate that rHmC1q-dependent chemotaxis might be driven via a HmC1q-binding protein located on the microglial cell surface. Taken together, these results highlight the importance of the interaction between C1q and C1qBP in microglial activation leading to nerve repair in the medicinal

  17. Interaction of HmC1q with leech microglial cells: involvement of C1qBP-related molecule in the induction of cell chemotaxis.

    Science.gov (United States)

    Tahtouh, Muriel; Garçon-Bocquet, Annelise; Croq, Françoise; Vizioli, Jacopo; Sautière, Pierre-Eric; Van Camp, Christelle; Salzet, Michel; Nagnan-le Meillour, Patricia; Pestel, Joël; Lefebvre, Christophe

    2012-02-22

    In invertebrates, the medicinal leech is considered to be an interesting and appropriate model to study neuroimmune mechanisms. Indeed, this non-vertebrate animal can restore normal function of its central nervous system (CNS) after injury. Microglia accumulation at the damage site has been shown to be required for axon sprouting and for efficient regeneration. We characterized HmC1q as a novel chemotactic factor for leech microglial cell recruitment. In mammals, a C1q-binding protein (C1qBP alias gC1qR), which interacts with the globular head of C1q, has been reported to participate in C1q-mediated chemotaxis of blood immune cells. In this study, we evaluated the chemotactic activities of a recombinant form of HmC1q and its interaction with a newly characterized leech C1qBP that acts as its potential ligand. Recombinant HmC1q (rHmC1q) was produced in the yeast Pichia pastoris. Chemotaxis assays were performed to investigate rHmC1q-dependent microglia migration. The involvement of a C1qBP-related molecule in this chemotaxis mechanism was assessed by flow cytometry and with affinity purification experiments. The cellular localization of C1qBP mRNA and protein in leech was investigated using immunohistochemistry and in situ hybridization techniques. rHmC1q-stimulated microglia migrate in a dose-dependent manner. This rHmC1q-induced chemotaxis was reduced when cells were preincubated with either anti-HmC1q or anti-human C1qBP antibodies. A C1qBP-related molecule was characterized in leech microglia. A previous study showed that recruitment of microglia is observed after HmC1q release at the cut end of axons. Here, we demonstrate that rHmC1q-dependent chemotaxis might be driven via a HmC1q-binding protein located on the microglial cell surface. Taken together, these results highlight the importance of the interaction between C1q and C1qBP in microglial activation leading to nerve repair in the medicinal leech.

  18. Crystalline Repository Project: Review and comment of the Leech Lake Reservation Business Committee: Draft area recommendation report

    International Nuclear Information System (INIS)

    1986-09-01

    The Leech Lake Reservation Business Committee (LLRBC) has reviewed five documents related to the US Department of Energy's Crystalline Repository Project (CRP). They are the ''National Survey of Crystalline Rocks,'' ''General Guidelines for the Recommendation of Sites for the Nuclear Waste Repositories;' Final Siting Guidelines (10 CFR Part 960),'' ''Regional Characterization Reports for the North Central Region,'' the ''Region to Area Screening Methodology Document'' (SMD) and the ''Draft Area Recommendation Report'' (DARR). The comments and discussions of issues contained in this review will be considered in the preparation of the Final Area Recommendation Report, which will formally identify potentially acceptable sites for a second national repository for the permanent disposal of high level nuclear waste. Following a review of the above referenced documents, the LLRBC has concluded that the identification of potentially acceptable sites in the Draft Area Recommendation Report is based upon inferior and incomplete technical information being applied to a flawed screening process which, among other deficiencies, pays little attention to the importance of hydrological factors in the siting process. Although the DOE prefers that comments from states and tribes be directed at the Draft Area Recommendation Report alone, the Leech Lake Reservation Business Committee is extremely concerned about inadequacies in the ''National Survey of Crystalline Rocks'' (ORCD-1), which serves as the foundation for all siting work done to date. The national survey was conducted utilizing little of the time or staffing required for this important phase of the Crystalline Repository Program. As a result, the national survey is based upon out-of-date scientific literature, exaggerates certain screening variables that favor the selection of regions in the eastern US and arbitrarily eliminated the few western crystalline rock bodies that passed the questionable screening process utilized

  19. La sanguijuela, un gusano en la historia de la salud The leeches, a worm in the history of health

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    María Pilar Manrique Sáez

    2008-12-01

    Full Text Available El uso de sanguijuelas ha sido una terapia que ha venido usándose desde las antiguas civilizaciones hasta principios del siglo XX como tratamiento indispensable para diversas dolencias, cayendo en desuso como consecuencia del gran avance científico y considerándose un tratamiento sin valor, atrasado y decadente. El presente articulo pretende dar a conocer la terapia con sanguijuelas, su auge desde la antigüedad, su decadencia y el nuevo renacer actual en el postoperatorio de la microcirugía plástica reconstructiva para prevenir el éxtasis venoso, así como en traumatología en el tratamiento de las artrosis. Dicha terapia se está aplicando en numerosos países, incluyendo España en donde su uso es una realidad en Hospitales y servicios muy concretos.The use of leeches is a medical therapy which has been used since ancient civilizations until the first decades of the XXth century. It is an irreplaceable remedy to treat many types of illness, however, it fell into disuse due to the increasing confidence in scientific development and because it became considered old-fashioned, obsolete and valueless. The present paper tries to release the therapy with leeches, its peak in the ancient times, its later disuse and the recent reappearance in the post-operative of plastic microsurgical reconstruction in order to prevent the poisoning ecstasy and also in the degenerative osteoarthritis treatment. This therapy is being applied to numerous countries, Spain included, where it is being used at hospitals in particular medical services.

  20. Evolutionary Origin of Body Axis Segmentation in Annelids and Arthropods

    Science.gov (United States)

    Shankland, S. Martin

    2003-01-01

    During the period of this report, we have made a number of important discoveries. To date this work has led to 4 peer-reviewed publications in primary research journals plus 1 minireview and 1 chapter in the proceedings of a meeting. Publications resulting from this grant support are enumerated at the end of the report. Two additional, on-going studies also described. 1. Using laser cell ablation, we have obtained evidence that an annelid - the leech Helobdella robusta - patterns the anteroposterior (AP) polarity of its nascent segment primordia independent of cell interactions oriented along the AP axis. 2. We cloned a Helobdella homologue (hro-hh) of the Drosophila segment polarity gene hedgehog, and used in situ hybridization and northern blots to characterize its expression in the embryo. 3. We have used laser cell ablations to examine the possible role of cell interactions during the developmental patterning of the 4 rostralmost "head" segments of the leech Helobdella robusta.

  1. First record of Stibarobdella moorei (Annelida, Hirudinea, Piscicolidae a marine leech parasitizing Octopus bimaculatus (Mollusca: Octopodidae from the Mexican Pacific coast

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    López-Peraza D. J.

    2017-12-01

    Full Text Available The occurrence of the parasitic marine leech Stibarobdella moorei (Oka, 1910 (Hirudinea: Piscicolidae along the northwest Mexican Pacific coast is described for the first time. This ectoparasite was collected from the skin of the Octopus bimaculatus (Verril, 1983 (Mollusca: Octopodidae. Stibarobdella loricata (Hardig, 1924 is synonymized with S. moorei as this species resembles other species of the genus based on tubercle patterns and the presence of papillae and a marginal fringe on the oral sucker. The present finding throws new light on the biodiversity and host preference of the ectoparasite and suggests a successful migration to unusual host. The coast of the Pacific Ocean, particularly in the Bay of Los Angeles, Baja California, Mexico is a new geographical distribution area for S. moorei, and O. bimaculatus is a new host reported for this leech. The morphology of this ectoparasite is briefly described.

  2. First record of Stibarobdella moorei (Annelida, Hirudinea, Piscicolidae) a marine leech parasitizing Octopus bimaculatus (Mollusca: Octopodidae) from the Mexican Pacific coast

    OpenAIRE

    López-Peraza D. J.; Hernández-Rodríguez M.; Barón-Sevilla B.; Bückle-Ramírez L. F.; Grano-Maldonado M. I.

    2017-01-01

    The occurrence of the parasitic marine leech Stibarobdella moorei (Oka, 1910) (Hirudinea: Piscicolidae) along the northwest Mexican Pacific coast is described for the first time. This ectoparasite was collected from the skin of the Octopus bimaculatus (Verril, 1983) (Mollusca: Octopodidae). Stibarobdella loricata (Hardig, 1924) is synonymized with S. moorei as this species resembles other species of the genus based on tubercle patterns and the presence of papillae and a marginal fringe on the...

  3. Mechanism of ammonia excretion in the freshwater leech Nephelopsis obscura: characterization of a primitive Rh protein and effects of high environmental ammonia

    Science.gov (United States)

    Quijada-Rodriguez, Alex R.; Treberg, Jason R.

    2015-01-01

    Remarkably little is known about nitrogenous excretion in freshwater invertebrates. In the current study, the nitrogen excretion mechanism in the carnivorous ribbon leech, Nephelopsis obscura, was investigated. Excretion experiments showed that the ribbon leech is ammonotelic, excreting 166.0 ± 8.6 nmol·grams fresh weight (gFW)−1·h−1 ammonia and 14.7 ± 1.9 nmol·gFW−1·h−1 urea. Exposure to high and low pH hampered and enhanced, respectively, ammonia excretion rates, indicating an acid-linked ammonia trapping mechanism across the skin epithelia. Accordingly, compared with body tissues, the skin exhibited elevated mRNA expression levels of a newly identified Rhesus protein and at least in tendency the Na+/K+-ATPase. Pharmacological experiments and enzyme assays suggested an ammonia excretion mechanism that involves the V-ATPase, Na+/K+-ATPase, and carbonic anhydrase, but not necessarily a functional microtubule system. Most importantly, functional expression studies of the identified Rh protein cloned from leech skin tissue revealed an ammonia transport capability of this protein when expressed in yeast. The leech Rh-ammonia transporter (NoRhp) is a member of the primitive Rh protein family, which is a sister group to the common ancestor of vertebrate ammonia-transporting Rh proteins. Exposure to high environmental ammonia (HEA) caused a new adjustment of body ammonia, accompanied with a decrease in NoRhp and Na+/K+-ATPase mRNA levels, but unaltered ammonia excretion rates. To our knowledge, this is only the second comprehensive study regarding the ammonia excretion mechanisms in a freshwater invertebrate, but our results show that basic processes of ammonia excretion appear to also be comparable to those found in freshwater fish, suggesting an early evolution of ionoregulatory mechanisms in freshwater organisms. PMID:26180186

  4. Infections of Hypostomus spp. by Trypanosoma spp. and leeches: a study of hematology and record of these hirudineans as potential vectors of these hemoflagellates

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    Lincoln Lima Corrêa

    Full Text Available Abstract Among Kinetoplastida, the Trypanosoma is the genus with the highest occurrence infecting populations of marine fish and freshwater in the world, with high levels of prevalence, causing influences fish health and consequent economic losses, mainly for fish populations in situation stress. This study investigated infections of Hypostomus spp. by Trypanosoma spp. and leeches, as well as blood parameters of this host in the network of tributaries of the Tapajós River in the state of Pará, in the eastern Amazon region in Brazil. Of the 47 hosts examined, 89.4% were parasitized by Trypanosoma spp. and 55.4% also had leeches attached around the mouth. The intensity of Trypanosoma spp. increased with the size of the host, but the body conditions were not influenced by the parasitism. The number of red blood cells, and hemoglobin, mean corpuscular volume (MCV, mean corpuscular hemoglobin concentration (MCHC, mean corpuscular hemoglobin (MCH, total number of leukocytes and thrombocytes showed variations and negative correlation with the intensity of Trypanosoma spp. in the blood of the hosts. The results suggest that the leeches were vectors of Trypanosoma spp. in Hypostomus spp.

  5. Antibiotic susceptibility of body surface and gut micro flora of two aquatic leech species (Hirudinaria manillensis and Hirudinaria javanica in Malaysia

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    Parimannan Sivachandran

    2013-08-01

    Full Text Available Objective: To elucidate the antibiotic susceptibility of body surface and gut associated microflora of two local aquatic leech species Hirudinaria manillensis and Hirudinaria javanica. Methods: Four commercially available antibiotics (doxycycline, chloramphenicol, tetracycline and ciprofloxacin were used in this study. A total of 13 isolated gut and two surface micro flora from Hirudinaria manillensis and two gut and two surface micro flora from Hirudinaria javanica were tested for their antibiotic susceptibility. Results: Based on the susceptibility, it was observed that all the isolated bacteria were found to be susceptible to at least three of the antibiotics except Microbacterium resistens, Serratia marcescens and Morganella morganii. This study also found that the bacterial species Bacillus fusiformis has displayed resistance against tetracycline and Tsukamurella inchonensis against chloramphenicol. Conclusions: Among all the antibiotics tested, ciprofloxacin was found to be the best bactericidal agent. The immersion of leeches in ciprofloxacin before the application to the patient may be beneficial to prevent invasive infection of the patient. Further study is needed to sterilize the live leech by immersion/oral mode of administration for the tested antibiotics.

  6. Impact of the redox-cycling herbicide diquat on transcript expression and antioxidant enzymatic activities of the freshwater snail Lymnaea stagnalis

    Energy Technology Data Exchange (ETDEWEB)

    Bouetard, Anthony, E-mail: anthony.bouetard@rennes.inra.fr [INRA, UMR INRA-Agrocampus Ouest ESE 0985, Equipe Ecotoxicologie et Qualite des Milieux Aquatiques, 65 rue de Saint-Brieuc, 35042 Rennes cedex (France); Besnard, Anne-Laure; Vassaux, Daniele; Lagadic, Laurent; Coutellec, Marie-Agnes [INRA, UMR INRA-Agrocampus Ouest ESE 0985, Equipe Ecotoxicologie et Qualite des Milieux Aquatiques, 65 rue de Saint-Brieuc, 35042 Rennes cedex (France)

    2013-01-15

    The presence of pesticides in the environment results in potential unwanted effects on non-target species. Freshwater organisms inhabiting water bodies adjacent to agricultural areas, such as ditches, ponds and marshes, are good models to test such effects as various pesticides may reach these habitats through several ways, including aerial drift, run-off, and drainage. Diquat is a non-selective herbicide used for crop protection or for weed control in such water bodies. In this study, we investigated the effects of diquat on a widely spread aquatic invertebrate, the holarctic freshwater snail Lymnaea stagnalis. Due to the known redox-cycling properties of diquat, we studied transcript expression and enzymatic activities relative to oxidative and general stress in the haemolymph and gonado-digestive complex (GDC). As diquat is not persistent, snails were exposed for short times (5, 24, and 48 h) to ecologically relevant concentrations (22.2, 44.4, and 222.2 {mu}g l{sup -1}) of diquat dibromide. RT-qPCR was used to quantify the transcription of genes encoding catalase (cat), a cytosolic superoxide dismutase (Cu/Zn-sod), a selenium-dependent glutathione peroxidase (gpx), a glutathione reductase (gred), the retinoid X receptor (rxr), two heat shock proteins (hsp40 and hsp70), cortactin (cor) and the two ribosomal genes r18S and r28s. Enzymatic activities of SOD, Gpx, Gred and glutathione S-transferase (GST) were investigated in the GDC using spectrophoto/fluorometric methods. Opposite trends were obtained in the haemolymph depending on the herbicide concentration. At the lowest concentration, effects were mainly observed after 24 h of exposure, with over-transcription of cor, hsp40, rxr, and sod, whereas higher concentrations down-regulated the expression of most of the studied transcripts, especially after 48 h of exposure. In the GDC, earlier responses were observed and the fold-change magnitude was generally much higher: transcription of all target genes increased

  7. Reversal of age-related learning deficiency by the vertebrate PACAP and IGF-1 in a novel invertebrate model of aging: the pond snail (Lymnaea stagnalis).

    Science.gov (United States)

    Pirger, Zsolt; Naskar, Souvik; László, Zita; Kemenes, György; Reglődi, Dóra; Kemenes, Ildikó

    2014-11-01

    With the increase of life span, nonpathological age-related memory decline is affecting an increasing number of people. However, there is evidence that age-associated memory impairment only suspends, rather than irreversibly extinguishes, the intrinsic capacity of the aging nervous system for plasticity (1). Here, using a molluscan model system, we show that the age-related decline in memory performance can be reversed by administration of the pituitary adenylate cyclase activating polypeptide (PACAP). Our earlier findings showed that a homolog of the vertebrate PACAP38 and its receptors exist in the pond snail (Lymnaea stagnalis) brain (2), and it is both necessary and instructive for memory formation after reward conditioning in young animals (3). Here we show that exogenous PACAP38 boosts memory formation in aged Lymnaea, where endogenous PACAP38 levels are low in the brain. Treatment with insulin-like growth factor-1, which in vertebrates was shown to transactivate PACAP type I (PAC1) receptors (4) also boosts memory formation in aged pond snails. Due to the evolutionarily conserved nature of these polypeptides and their established role in memory and synaptic plasticity, there is a very high probability that they could also act as "memory rejuvenating" agents in humans. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America.

  8. Crystal structure of Lymnaea stagnalis AChBP complexed with the potent nAChR antagonist DHβE suggests a unique mode of antagonism.

    Directory of Open Access Journals (Sweden)

    Azadeh Shahsavar

    Full Text Available Nicotinic acetylcholine receptors (nAChRs are pentameric ligand-gated ion channels that belong to the Cys-loop receptor superfamily. These receptors are allosteric proteins that exist in different conformational states, including resting (closed, activated (open, and desensitized (closed states. The acetylcholine binding protein (AChBP is a structural homologue of the extracellular ligand-binding domain of nAChRs. In previous studies, the degree of the C-loop radial extension of AChBP has been assigned to different conformational states of nAChRs. It has been suggested that a closed C-loop is preferred for the active conformation of nAChRs in complex with agonists whereas an open C-loop reflects an antagonist-bound (closed state. In this work, we have determined the crystal structure of AChBP from the water snail Lymnaea stagnalis (Ls in complex with dihydro-β-erythroidine (DHβE, which is a potent competitive antagonist of nAChRs. The structure reveals that binding of DHβE to AChBP imposes closure of the C-loop as agonists, but also a shift perpendicular to previously observed C-loop movements. These observations suggest that DHβE may antagonize the receptor via a different mechanism compared to prototypical antagonists and toxins.

  9. Considerations for test design to accommodate energy-budget models in ecotoxicology: a case study for acetone in the pond snail Lymnaea stagnalis.

    Science.gov (United States)

    Barsi, Alpar; Jager, Tjalling; Collinet, Marc; Lagadic, Laurent; Ducrot, Virginie

    2014-07-01

    Toxicokinetic-toxicodynamic (TKTD) modeling offers many advantages in the analysis of ecotoxicity test data. Calibration of TKTD models, however, places different demands on test design compared with classical concentration-response approaches. In the present study, useful complementary information is provided regarding test design for TKTD modeling. A case study is presented for the pond snail Lymnaea stagnalis exposed to the narcotic compound acetone, in which the data on all endpoints were analyzed together using a relatively simple TKTD model called DEBkiss. Furthermore, the influence of the data used for calibration on accuracy and precision of model parameters is discussed. The DEBkiss model described toxic effects on survival, growth, and reproduction over time well, within a single integrated analysis. Regarding the parameter estimates (e.g., no-effect concentration), precision rather than accuracy was affected depending on which data set was used for model calibration. In addition, the present study shows that the intrinsic sensitivity of snails to acetone stays the same across different life stages, including the embryonic stage. In fact, the data on egg development allowed for selection of a unique metabolic mode of action for the toxicant. Practical and theoretical considerations for test design to accommodate TKTD modeling are discussed in the hope that this information will aid other researchers to make the best possible use of their test animals. © 2014 SETAC.

  10. 'Different strokes for different folks': geographically isolated strains of Lymnaea stagnalis only respond to sympatric predators and have different memory forming capabilities.

    Science.gov (United States)

    Orr, Michael V; Hittel, Karla; Lukowiak, Ken

    2009-07-01

    Gaining insight into how natural trait variation is manifest in populations shaped by differential environmental factors is crucial to understanding the evolution, ecology and sensory biology of natural populations. We have demonstrated that lab-reared Lymnaea detect and respond to the scent of a crayfish predator with specific, appropriate anti-predator behavioral responses, including enhanced long-term memory (LTM) formation, and that such predator detection significantly alters the electrophysiological activity of RPeD1, a neuron that is a necessary site for LTM formation. Here we ask: (1) do distinct populations of wild Lymnaea stagnalis respond only to sympatric predators and if so, can these traits be quantified at both the behavioral and neurophysiological levels, and (2) does the presence of a non-sympatric predator elicit anti-predator behaviors including augmentation of LTM? We tested three different populations of wild (i.e. not lab-reared) snails freshly collected from their natural habitat: (1) polders near Utrecht in The Netherlands, (2) six seasonally isolated ponds in the Belly River drainage in southern Alberta, Canada and (3) a 20-year-old human-made dugout pond in southern Alberta. We found strain-specific variations in the ability to form LTM and that only a sympatric predator evoked anti-predatory behaviors, including enhanced LTM formation and changes in RPeD1 activity.

  11. Cell cycle-related fluctuations in transcellular ionic currents and plasma membrane Ca2+/Mg2+ ATPase activity during early cleavages of Lymnaea stagnalis embryos.

    Science.gov (United States)

    Zivkovic, Danica; Créton, Robbert; Dohmen, René

    1991-08-01

    During the first four mitotic division cycles of Lymnaea stagnalis embryos, we have detected cell cycle-dependent changes in the pattern of transcellular ionic currents and membrane-bound Ca 2+ -stimulated ATPase activity. Ionic currents ranging from 0.05 to 2.50 μA/cm 2 have been measured using the vibrating probe technique. Enzyme activity was detected using Ando's cytochemical method (Ando et al. 1981) which reveals Ca 2+ /Mg 2+ ATPase localization at the ultrastructural level, and under high-stringency conditions with respect to calcium availability, it reveals Ca 2+ -stimulated ATPase. The ionic currents and Ca 2+ -stimulated ATPase localization have in common that important changes occur during the M-phase of the cell cycles. Minimal outward current at the vegetal pole coincides with metaphase/anaphase. Maximal inward current at the animal pole coincides with the onset of cytokinesis at that pole. Ca 2+ -stimulated ATPase is absent from one half of the embryo at metaphase/anaphase of the two- and four-cell stage, whereas it is present in all cells during the remaining part of the cell cycle. Since fluctuations of cytosolic free calcium concentrations appear to correlate with both karyokinesis and cytokinesis, we speculate that part of the cyclic pattern of Ca 2+ -stimulated ATPase localization and of the transcellular ionic currents reflects the elevation of cytosolic free calcium concentration during the M-phase.

  12. Accumulation of free and covalently bound microcystins in tissues of Lymnaea stagnalis (Gastropoda) following toxic cyanobacteria or dissolved microcystin-LR exposure

    International Nuclear Information System (INIS)

    Lance, Emilie; Neffling, Milla-Riina; Gerard, Claudia; Meriluoto, Jussi; Bormans, Myriam

    2010-01-01

    Accumulation of free microcystins (MCs) in freshwater gastropods has been demonstrated but accumulation of MCs covalently bound to tissues has never been considered so far. Here, we follow the accumulation of total (free and bound) MCs in Lymnaea stagnalis exposed to i) dissolved MC-LR (33 and 100 μg L -1 ) and ii) Planktothrix agardhii suspensions producing 5 and 33 μg MC-LR equivalents L -1 over a 5-week period, and after a 3-week depuration period. Snails exposed to dissolved MC-LR accumulated up to 0.26 μg total MCs g -1 dry weight (DW), with no detection of bound MCs. Snails exposed to MCs producing P. agardhii accumulated up to 69.9 μg total MCs g -1 DW, of which from 17.7 to 66.7% were bound. After depuration, up to 15.3 μg g -1 DW of bound MCs were detected in snails previously exposed to toxic cyanobacteria, representing a potential source of MCs transfer through the food web. - The study concerns accumulation and elimination of both free and bound microcystins (MCs) in tissues of a gastropod exposed to MCs producing cyanobacteria or dissolved MC-LR.

  13. Accumulation of free and covalently bound microcystins in tissues of Lymnaea stagnalis (Gastropoda) following toxic cyanobacteria or dissolved microcystin-LR exposure.

    Science.gov (United States)

    Lance, Emilie; Neffling, Milla-Riina; Gérard, Claudia; Meriluoto, Jussi; Bormans, Myriam

    2010-03-01

    Accumulation of free microcystins (MCs) in freshwater gastropods has been demonstrated but accumulation of MCs covalently bound to tissues has never been considered so far. Here, we follow the accumulation of total (free and bound) MCs in Lymnaea stagnalis exposed to i) dissolved MC-LR (33 and 100 microg L(-1)) and ii) Planktothrix agardhii suspensions producing 5 and 33 microg MC-LR equivalents L(-1) over a 5-week period, and after a 3-week depuration period. Snails exposed to dissolved MC-LR accumulated up to 0.26 microg total MCs g(-1) dry weight (DW), with no detection of bound MCs. Snails exposed to MCs producing P. agardhii accumulated up to 69.9 microg total MCs g(-1) DW, of which from 17.7 to 66.7% were bound. After depuration, up to 15.3 microg g(-1) DW of bound MCs were detected in snails previously exposed to toxic cyanobacteria, representing a potential source of MCs transfer through the food web. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

  14. Accumulation of free and covalently bound microcystins in tissues of Lymnaea stagnalis (Gastropoda) following toxic cyanobacteria or dissolved microcystin-LR exposure

    Energy Technology Data Exchange (ETDEWEB)

    Lance, Emilie, E-mail: emilie.lance@live.f [UMR CNRS Ecobio 6553, University of Rennes 1, Campus de Beaulieu, 265 Avenue du General Leclerc, 35042 Rennes Cedex (France); Neffling, Milla-Riina [Department of Biochemistry and Pharmacy, Abo Akademi University, Tykistoekatu 6, FI-20520 Turku (Finland); Gerard, Claudia [UMR CNRS Ecobio 6553, University of Rennes 1, Campus de Beaulieu, 265 Avenue du General Leclerc, 35042 Rennes Cedex (France); Meriluoto, Jussi [Department of Biochemistry and Pharmacy, Abo Akademi University, Tykistoekatu 6, FI-20520 Turku (Finland); Bormans, Myriam [UMR CNRS Ecobio 6553, University of Rennes 1, Campus de Beaulieu, 265 Avenue du General Leclerc, 35042 Rennes Cedex (France)

    2010-03-15

    Accumulation of free microcystins (MCs) in freshwater gastropods has been demonstrated but accumulation of MCs covalently bound to tissues has never been considered so far. Here, we follow the accumulation of total (free and bound) MCs in Lymnaea stagnalis exposed to i) dissolved MC-LR (33 and 100 mug L{sup -1}) and ii) Planktothrix agardhii suspensions producing 5 and 33 mug MC-LR equivalents L{sup -1} over a 5-week period, and after a 3-week depuration period. Snails exposed to dissolved MC-LR accumulated up to 0.26 mug total MCs g{sup -1} dry weight (DW), with no detection of bound MCs. Snails exposed to MCs producing P. agardhii accumulated up to 69.9 mug total MCs g{sup -1} DW, of which from 17.7 to 66.7% were bound. After depuration, up to 15.3 mug g{sup -1} DW of bound MCs were detected in snails previously exposed to toxic cyanobacteria, representing a potential source of MCs transfer through the food web. - The study concerns accumulation and elimination of both free and bound microcystins (MCs) in tissues of a gastropod exposed to MCs producing cyanobacteria or dissolved MC-LR.

  15. Energy utilization and gluconeogenesis in isolated leech segmental ganglia: Quantitative studies on the control and cellular localization of endogenous glycogen.

    Science.gov (United States)

    Pennington, A J; Pentreath, V W

    1988-01-01

    The isolated segmental ganglia of the horse leech Haemopis sanguisuga were used as a model system to study the utilization and control of glycogen stores within nervous tissue. The glycogen in the ganglia was extracted and assayed fluorimentrically and its cellular localization and turnover studied by autoradiography in conjunction with [(3)H]glucose. We measured the glycogen after various periods of electrical stimulation and after incubation with K(+), Ca(2+), ouabain and glucose. The results for each experimental ganglion were compared to a paired control ganglion and the results analysed by paired t-tests. Electrical stimulation caused sequential changes in glycogen levels: a reduction of up to 67% (5-10 min); followed by an increase of up to 124% (between 15-50 min); followed by a reduction of up to 63% (60-90 min). Values were calculated for glucose utilization (e.g. 0.53 ?mol glucose/gm wet weight/min after 90 min) and estimates derived for glucose consumption per action potential per neuron (e.g. 0.12 fmol at 90 min). Glucose (1.5-10 mM) increased the amount of glycogen (1.5 mM by 30% at 60 min) and attenuated the effects of electrical stimulation. Ouabain (1 mM) blocked the effect of 5 min electrical stimulation. Nine millimolar K(+) increased glycogen by 27% after 10 min and decreased glycogen by 34% after 60 min; 3 mM Ca(2+) had no effect after 10 or 20 min and decreased glycogen by 29% after 60 min. Other concentrations of K(+) and Ca(2+) reduced glycogen after 60 min. Autoradiographic analysis demonstrated that the effects of elevated K(+) were principally within the glial cells. We conclude that (i) the glycogen stores in the glial cells of leech segmental ganglia provide an endogenous energy source which can support sustained neuronal activity, (ii) both electrical stimulation and elevated K(+) can induce gluconeogenesis within the ganglia, (iii) that electrical activation of neurons produces changes in the glycogen in the glial cells which are

  16. A central pattern generator producing alternative outputs: phase relations of leech heart motor neurons with respect to premotor synaptic input.

    Science.gov (United States)

    Norris, Brian J; Weaver, Adam L; Wenning, Angela; García, Paul S; Calabrese, Ronald L

    2007-11-01

    The central pattern generator (CPG) for heartbeat in leeches consists of seven identified pairs of segmental heart interneurons and one unidentified pair. Four of the identified pairs and the unidentified pair of interneurons make inhibitory synaptic connections with segmental heart motor neurons. The CPG produces a side-to-side asymmetric pattern of intersegmental coordination among ipsilateral premotor interneurons corresponding to a similarly asymmetric fictive motor pattern in heart motor neurons, and asymmetric constriction pattern of the two tubular hearts: synchronous and peristaltic. Using extracellular techniques, we recorded, in 61 isolated nerve cords, the activity of motor neurons in conjunction with the phase reference premotor heart interneuron, HN(4), and another premotor interneuron that allowed us to assess the coordination mode. These data were then coupled with a previous description of the temporal pattern of premotor interneuron activity in the two coordination modes to synthesize a global phase diagram for the known elements of the CPG and the entire motor neuron ensemble. These average data reveal the stereotypical side-to-side asymmetric patterns of intersegmental coordination among the motor neurons and show how this pattern meshes with the activity pattern of premotor interneurons. Analysis of animal-to-animal variability in this coordination indicates that the intersegmental phase progression of motor neuron activity in the midbody in the peristaltic coordination mode is the most stereotypical feature of the fictive motor pattern. Bilateral recordings from motor neurons corroborate the main features of the asymmetric motor pattern.

  17. A central pattern generator producing alternative outputs: pattern, strength, and dynamics of premotor synaptic input to leech heart motor neurons.

    Science.gov (United States)

    Norris, Brian J; Weaver, Adam L; Wenning, Angela; García, Paul S; Calabrese, Ronald L

    2007-11-01

    The central pattern generator (CPG) for heartbeat in medicinal leeches consists of seven identified pairs of segmental heart interneurons and one unidentified pair. Four of the identified pairs and the unidentified pair of interneurons make inhibitory synaptic connections with segmental heart motor neurons. The CPG produces a side-to-side asymmetric pattern of intersegmental coordination among ipsilateral premotor interneurons corresponding to a similarly asymmetric fictive motor pattern in heart motor neurons, and asymmetric constriction pattern of the two tubular hearts, synchronous and peristaltic. Using extracellular recordings from premotor interneurons and voltage-clamp recordings of ipsilateral segmental motor neurons in 69 isolated nerve cords, we assessed the strength and dynamics of premotor inhibitory synaptic output onto the entire ensemble of heart motor neurons and the associated conduction delays in both coordination modes. We conclude that premotor interneurons establish a stereotypical pattern of intersegmental synaptic connectivity, strengths, and dynamics that is invariant across coordination modes, despite wide variations among preparations. These data coupled with a previous description of the temporal pattern of premotor interneuron activity and relative phasing of motor neuron activity in the two coordination modes enable a direct assessment of how premotor interneurons through their temporal pattern of activity and their spatial pattern of synaptic connectivity, strengths, and dynamics coordinate segmental motor neurons into a functional pattern of activity.

  18. New tentacled leech Ceratobdella quadricornuta n. g., n. sp. (Hirudinida: Piscicolidae) parasitic on the starry skate Raja georgiana Norman from the Scotia Sea, Antarctica.

    Science.gov (United States)

    Utevsky, Andrei; Gordeev, Ilya

    2015-07-01

    A new fish leech Ceratobdella quadricornuta n. g., n. sp. (Hirudinida: Piscicolidae), a parasite of the Antarctic skate Raja georgiana Norman (Rajiformes: Rajidae) collected between the Falkland Islands and South Georgia Island in the Scotia Sea, is described and compared with related genera. Ceratobdella quadricornuta is characterised by an uncommon appearance of its anterior sucker bearing four well-developed tentacles and a unique combination of features of the reproductive and digestive systems: crop and intestine equally developed, posterior crop caeca separated; accessory glands, conductive tissue and external copulatory area lacking; common part of ejaculatory ducts (common atrium) voluminous and muscular, male copulatory bursa short, small ovisacs opening into female copulatory bursa (vagina).

  19. Two Strains of Lymnaea stagnalis and the Progeny from Their Mating Display Differential Memory-Forming Ability on Associative Learning Tasks.

    Science.gov (United States)

    Sunada, Hiroshi; Totani, Yuki; Nakamura, Ryota; Sakakibara, Manabu; Lukowiak, Ken; Ito, Etsuro

    2017-01-01

    The pond snail Lymnaea stagnalis learns and forms long-term memory (LTM) following both operant conditioning of aerial respiratory behavior and classical conditioning of taste aversive behavior. In the present study, we examined whether there are interstrain differences in the ability to form LTM following these two types of conditioning. A strain of Lymnaea (TC1) collected in Alberta, Canada exhibits superior memory-forming ability following aerial respiratory operant conditioning compared to a laboratory-reared strain of Lymnaea from Netherlands known as the Dutch strain. We asked whether the offspring of the Canadian TC1 and Dutch snails (i.e., filial 1 (F 1 ) cross snails) would have the superior memory ability and found, rather, that their memory ability was average like the Dutch snails. That is, the Canadian TC1 snails have superior ability for LTM formation following aerial respiratory operant conditioning, but the Dutch and the generated F 1 cross have average ability for memory forming. We next examined the Canadian TC1, Dutch and F 1 cross snails for their ability to learn and form memory following conditioned taste aversion (CTA). All three populations showed similar associative CTA responses. However, both LTM formation and the ratio of good-to-poor performers in the memory retention test were much better in the Dutch snails than the Canadian TC1 and F 1 cross snails. The memory abilities of the Canadian TC1 and F 1 cross snails were average. Our present findings, therefore, suggest that snails of different strains have different memory abilities, and the F 1 cross snails do not inherit the memory ability from the smart strain. To our knowledge, there have been a limited number of studies examining differences in memory ability among invertebrate strains, with the exception of studies using mutant flies.

  20. Two Strains of Lymnaea stagnalis and the Progeny from Their Mating Display Differential Memory-Forming Ability on Associative Learning Tasks

    Directory of Open Access Journals (Sweden)

    Hiroshi Sunada

    2017-09-01

    Full Text Available The pond snail Lymnaea stagnalis learns and forms long-term memory (LTM following both operant conditioning of aerial respiratory behavior and classical conditioning of taste aversive behavior. In the present study, we examined whether there are interstrain differences in the ability to form LTM following these two types of conditioning. A strain of Lymnaea (TC1 collected in Alberta, Canada exhibits superior memory-forming ability following aerial respiratory operant conditioning compared to a laboratory-reared strain of Lymnaea from Netherlands known as the Dutch strain. We asked whether the offspring of the Canadian TC1 and Dutch snails (i.e., filial 1 (F1 cross snails would have the superior memory ability and found, rather, that their memory ability was average like the Dutch snails. That is, the Canadian TC1 snails have superior ability for LTM formation following aerial respiratory operant conditioning, but the Dutch and the generated F1 cross have average ability for memory forming. We next examined the Canadian TC1, Dutch and F1 cross snails for their ability to learn and form memory following conditioned taste aversion (CTA. All three populations showed similar associative CTA responses. However, both LTM formation and the ratio of good-to-poor performers in the memory retention test were much better in the Dutch snails than the Canadian TC1 and F1 cross snails. The memory abilities of the Canadian TC1 and F1 cross snails were average. Our present findings, therefore, suggest that snails of different strains have different memory abilities, and the F1 cross snails do not inherit the memory ability from the smart strain. To our knowledge, there have been a limited number of studies examining differences in memory ability among invertebrate strains, with the exception of studies using mutant flies.

  1. Involvement of insulin-like peptide in long-term synaptic plasticity and long-term memory of the pond snail Lymnaea stagnalis.

    Science.gov (United States)

    Murakami, Jun; Okada, Ryuichi; Sadamoto, Hisayo; Kobayashi, Suguru; Mita, Koichi; Sakamoto, Yuki; Yamagishi, Miki; Hatakeyama, Dai; Otsuka, Emi; Okuta, Akiko; Sunada, Hiroshi; Takigami, Satoshi; Sakakibara, Manabu; Fujito, Yutaka; Awaji, Masahiko; Moriyama, Shunsuke; Lukowiak, Ken; Ito, Etsuro

    2013-01-02

    The pond snail Lymnaea stagnalis is capable of learning taste aversion and consolidating this learning into long-term memory (LTM) that is called conditioned taste aversion (CTA). Previous studies showed that some molluscan insulin-related peptides (MIPs) were upregulated in snails exhibiting CTA. We thus hypothesized that MIPs play an important role in neurons underlying the CTA-LTM consolidation process. To examine this hypothesis, we first observed the distribution of MIP II, a major peptide of MIPs, and MIP receptor and determined the amounts of their mRNAs in the CNS. MIP II was only observed in the light green cells in the cerebral ganglia, but the MIP receptor was distributed throughout the entire CNS, including the buccal ganglia. Next, when we applied exogenous mammalian insulin, secretions from MIP-containing cells or partially purified MIPs, to the isolated CNS, we observed a long-term change in synaptic efficacy (i.e., enhancement) of the synaptic connection between the cerebral giant cell (a key interneuron for CTA) and the B1 motor neuron (a buccal motor neuron). This synaptic enhancement was blocked by application of an insulin receptor antibody to the isolated CNS. Finally, injection of the insulin receptor antibody into the snail before CTA training, while not blocking the acquisition of taste aversion learning, blocked the memory consolidation process; thus, LTM was not observed. These data suggest that MIPs trigger changes in synaptic connectivity that may be correlated with the consolidation of taste aversion learning into CTA-LTM in the Lymnaea CNS.

  2. Pituitary adenylate cyclase activating polypeptide (PACAP) and its receptors are present and biochemically active in the central nervous system of the pond snail Lymnaea stagnalis.

    Science.gov (United States)

    Pirger, Zsolt; Laszlo, Zita; Hiripi, Laszlo; Hernadi, Laszlo; Toth, Gabor; Lubics, Andrea; Reglodi, Dora; Kemenes, Gyorgy; Mark, Laszlo

    2010-11-01

    PACAP is a highly conserved adenylate cyclase (AC) activating polypeptide, which, along with its receptors (PAC1-R, VPAC1, and VPAC2), is expressed in both vertebrate and invertebrate nervous systems. In vertebrates, PACAP has been shown to be involved in associative learning, but it is not known if it plays a similar role in invertebrates. To prepare the way for a detailed investigation into the possible role of PACAP and its receptors in a suitable invertebrate model of learning and memory, here, we undertook a study of their expression and biochemical role in the central nervous system of the pond snail Lymnaea stagnalis. Lymnaea is one of the best established invertebrate model systems to study the molecular mechanisms of learning and memory, including the role of cyclic AMP-activated signaling mechanisms, which crucially depend on the learning-induced activation of AC. However, there was no information available on the expression of PACAP and its receptors in sensory structures and central ganglia of the Lymnaea nervous system known to be involved in associative learning or whether or not PACAP can actually activate AC in these ganglia. Here, using matrix-assisted laser desorption ionization time of flight (MALDI-TOF) and immunohistochemistry, we established the presence of PACAP-like peptides in the cerebral ganglia and the lip region of Lymnaea. The MALDI-TOF data indicated an identity with mammalian PACAP-27 and the presence of a squid-like PACAP-38 highly homologous to vertebrate PACAP-38. We also showed that PACAP, VIP, and maxadilan stimulated the synthesis of cAMP in Lymnaea cerebral ganglion homogenates and that this effect was blocked by the appropriate general and selective PACAP receptor antagonists.

  3. The LEECH Exoplanet Imaging Survey: Characterization of the Coldest Directly Imaged Exoplanet, GJ 504 b, and Evidence for Superstellar Metallicity

    Science.gov (United States)

    Skemer, Andrew J.; Morley, Caroline V.; Zimmerman, Neil T.; Skrutskie, Michael F.; Leisenring, Jarron; Buenzli, Esther; Bonnefoy, Mickael; Bailey, Vanessa; Hinz, Philip; Defrére, Denis; Esposito, Simone; Apai, Dániel; Biller, Beth; Brandner, Wolfgang; Close, Laird; Crepp, Justin R.; De Rosa, Robert J.; Desidera, Silvano; Eisner, Josh; Fortney, Jonathan; Freedman, Richard; Henning, Thomas; Hofmann, Karl-Heinz; Kopytova, Taisiya; Lupu, Roxana; Maire, Anne-Lise; Males, Jared R.; Marley, Mark; Morzinski, Katie; Oza, Apurva; Patience, Jenny; Rajan, Abhijith; Rieke, George; Schertl, Dieter; Schlieder, Joshua; Stone, Jordan; Su, Kate; Vaz, Amali; Visscher, Channon; Ward-Duong, Kimberly; Weigelt, Gerd; Woodward, Charles E.

    2016-02-01

    As gas giant planets and brown dwarfs radiate away the residual heat from their formation, they cool through a spectral type transition from L to T, which encompasses the dissipation of cloud opacity and the appearance of strong methane absorption. While there are hundreds of known T-type brown dwarfs, the first generation of directly imaged exoplanets were all L type. Recently, Kuzuhara et al. announced the discovery of GJ 504 b, the first T dwarf exoplanet. GJ 504 b provides a unique opportunity to study the atmosphere of a new type of exoplanet with a ˜500 K temperature that bridges the gap between the first directly imaged planets (˜1000 K) and our own solar system's Jupiter (˜130 K). We observed GJ 504 b in three narrow L-band filters (3.71, 3.88, and 4.00 μm), spanning the red end of the broad methane fundamental absorption feature (3.3 μm) as part of the LBTI Exozodi Exoplanet Common Hunt (LEECH) exoplanet imaging survey. By comparing our new photometry and literature photometry with a grid of custom model atmospheres, we were able to fit GJ 504 b's unusual spectral energy distribution for the first time. We find that GJ 504 b is well fit by models with the following parameters: Teff = 544 ± 10 K, g Germany. LBT Corporation partners are the University of Arizona on behalf of the Arizona university system; Istituto Nazionale di Astrophisica, Italy; LBT Beteiligungsgesellschaft, Germany, representing the Max-Planck Society, the Astrophysical Institute Potsdam, and Heidelberg University; The Ohio State University, and the Research Corporation, on behalf of the University of Notre Dame, University of Minnesota, and University of Virginia.

  4. Effects of chronic waterborne nickel exposure on growth, ion homeostasis, acid-base balance, and nickel uptake in the freshwater pulmonate snail, Lymnaea stagnalis.

    Science.gov (United States)

    Niyogi, Som; Brix, Kevin V; Grosell, Martin

    2014-05-01

    The freshwater pulmonate snail, Lymnaea stagnalis, is the most sensitive aquatic organism tested to date for Ni. We undertook a series of experiments to investigate the underlying mechanism(s) for this observed hypersensitivity. Consistent with previous experiments, juvenile snail growth in a 21-day exposure was reduced by 48% relative to the control when exposed to 1.3 μg l(-1) Ni (EC20 less than the lowest concentration tested). Ca(2+) homeostasis was significantly disrupted by Ni exposure as demonstrated by reductions in net Ca(2+) uptake, and reductions in Ca(2+) concentrations in the hemolymph and soft tissues. We also observed reduced soft tissue [Mg(2+)]. Snails underwent a significant alkalosis with hemolymph pH increasing from 8.1 to 8.3 and hemolymph TCO2 increasing from 19 to 22 mM in control versus Ni-exposed snails, respectively. Unlike in previous studies with Co and Pb, snail feeding rates were found to be unaffected by Ni at the end of the exposure. Snails accumulated Ni in the soft tissue in a concentration-dependent manner, and Ni uptake experiments with (63)Ni revealed a biphasic uptake profile - a saturable high affinity component at low exposure concentrations (36-189 nM) and a linear component at the high exposure concentrations (189-1,897 nM). The high affinity transport system had an apparent Km of 89 nM Ni(2+) and Vmax of 2.4 nmol g(-1)h(-1). This equates to a logK of 7.1, significantly higher than logK's (2.6-5.2) for any other aquatic organisms evaluated to date, which will have implications for Biotic Ligand Model development. Finally, pharmacological inhibitors that block Ca(2+) uptake pathways in snails did not inhibit Ni uptake, suggesting that the uptake of Ni does not occur via Ca(2+) uptake pathways. As with Cu and Pb, the exact mechanism for the significant disruption in Ca(2+) homeostasis and reduction in juvenile snail growth remains unknown. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. THE LEECH EXOPLANET IMAGING SURVEY: CHARACTERIZATION OF THE COLDEST DIRECTLY IMAGED EXOPLANET, GJ 504 b, AND EVIDENCE FOR SUPERSTELLAR METALLICITY

    Energy Technology Data Exchange (ETDEWEB)

    Skemer, Andrew J.; Leisenring, Jarron; Bailey, Vanessa; Hinz, Philip; Defrére, Denis; Apai, Dániel; Close, Laird; Eisner, Josh [Steward Observatory, University of Arizona, 933 North Cherry Ave. Tucson, AZ 85721 (United States); Morley, Caroline V.; Fortney, Jonathan [University of California, Santa Cruz, 1156 High St. Santa Cruz, CA 95064 (United States); Zimmerman, Neil T.; Buenzli, Esther; Bonnefoy, Mickael; Biller, Beth; Brandner, Wolfgang [Max Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg (Germany); Skrutskie, Michael F. [University of Virginia, 530 McCormick Rd., Charlottesville, VA 22904 (United States); Esposito, Simone [Istituto Nazionale di Astrofisica-Arcetri Astrophysical Observatory, Largo Enrico Fermi 5, 50125, Florence (Italy); Crepp, Justin R. [Notre Dame University, 225 Nieuwland Science Hall, Notre Dame, IN 46556 (United States); De Rosa, Robert J. [Arizona State University, 781 South Terrace Rd, Tempe, AZ 85281 (United States); Desidera, Silvano [Istituto Nazionale di Astrofisica-Padova Astronomical Observatory, Vicolo dell’Osservatorio 5, 35122 Padova (Italy); and others

    2016-02-01

    As gas giant planets and brown dwarfs radiate away the residual heat from their formation, they cool through a spectral type transition from L to T, which encompasses the dissipation of cloud opacity and the appearance of strong methane absorption. While there are hundreds of known T-type brown dwarfs, the first generation of directly imaged exoplanets were all L type. Recently, Kuzuhara et al. announced the discovery of GJ 504 b, the first T dwarf exoplanet. GJ 504 b provides a unique opportunity to study the atmosphere of a new type of exoplanet with a ∼500 K temperature that bridges the gap between the first directly imaged planets (∼1000 K) and our own solar system's Jupiter (∼130 K). We observed GJ 504 b in three narrow L-band filters (3.71, 3.88, and 4.00 μm), spanning the red end of the broad methane fundamental absorption feature (3.3 μm) as part of the LBTI Exozodi Exoplanet Common Hunt (LEECH) exoplanet imaging survey. By comparing our new photometry and literature photometry with a grid of custom model atmospheres, we were able to fit GJ 504 b's unusual spectral energy distribution for the first time. We find that GJ 504 b is well fit by models with the following parameters: T{sub eff} = 544 ± 10 K, g < 600 m s{sup −2}, [M/H] = 0.60 ± 0.12, cloud opacity parameter of f{sub sed} = 2–5, R = 0.96 ± 0.07 R{sub Jup}, and log(L) = −6.13 ± 0.03 L{sub ⊙}, implying a hot start mass of 3–30 M{sub jup} for a conservative age range of 0.1–6.5 Gyr. Of particular interest, our model fits suggest that GJ 504 b has a superstellar metallicity. Since planet formation can create objects with nonstellar metallicities, while binary star formation cannot, this result suggests that GJ 504 b formed like a planet, not like a binary companion.

  6. Na(+)/K(+) pump interacts with the h-current to control bursting activity in central pattern generator neurons of leeches.

    Science.gov (United States)

    Kueh, Daniel; Barnett, William H; Cymbalyuk, Gennady S; Calabrese, Ronald L

    2016-09-02

    The dynamics of different ionic currents shape the bursting activity of neurons and networks that control motor output. Despite being ubiquitous in all animal cells, the contribution of the Na(+)/K(+) pump current to such bursting activity has not been well studied. We used monensin, a Na(+)/H(+) antiporter, to examine the role of the pump on the bursting activity of oscillator heart interneurons in leeches. When we stimulated the pump with monensin, the period of these neurons decreased significantly, an effect that was prevented or reversed when the h-current was blocked by Cs(+). The decreased period could also occur if the pump was inhibited with strophanthidin or K(+)-free saline. Our monensin results were reproduced in model, which explains the pump's contributions to bursting activity based on Na(+) dynamics. Our results indicate that a dynamically oscillating pump current that interacts with the h-current can regulate the bursting activity of neurons and networks.

  7. Comparison of the effects of millimeter wave irradiation, general bath heating, and localized heating on neuronal activity in the leech ganglion

    Science.gov (United States)

    Romanenko, Sergii; Siegel, Peter H.; Wagenaar, Daniel A.; Pikov, Victor

    2013-02-01

    The use of electrically-induced neuromodulation has grown in importance in the treatment of multiple neurological disorders such as Parkinson's disease, dystonia, epilepsy, chronic pain, cluster headaches and others. While electrical current can be applied locally, it requires placing stimulation electrodes in direct contact with the neural tissue. Our goal is to develop a method for localized application of electromagnetic energy to the brain without direct tissue contact. Toward this goal, we are experimenting with the wireless transmission of millimeter wave (MMW) energy in the 10-100 GHz frequency range, where penetration and focusing can be traded off to provide non-contact irradiation of the cerebral cortex. Initial experiments have been conducted on freshly-isolated leech ganglia to evaluate the real-time changes in the activity of individual neurons upon exposure to the MMW radiation. The initial results indicate that low-intensity MMWs can partially suppress the neuronal activity. This is in contrast to general bath heating, which had an excitatory effect on the neuronal activity. Further studies are underway to determine the changes in the state of the membrane channels that might be responsible for the observed neuromodulatory effects.

  8. Na+/K+ pump interacts with the h-current to control bursting activity in central pattern generator neurons of leeches

    Science.gov (United States)

    Kueh, Daniel; Barnett, William H; Cymbalyuk, Gennady S; Calabrese, Ronald L

    2016-01-01

    The dynamics of different ionic currents shape the bursting activity of neurons and networks that control motor output. Despite being ubiquitous in all animal cells, the contribution of the Na+/K+ pump current to such bursting activity has not been well studied. We used monensin, a Na+/H+ antiporter, to examine the role of the pump on the bursting activity of oscillator heart interneurons in leeches. When we stimulated the pump with monensin, the period of these neurons decreased significantly, an effect that was prevented or reversed when the h-current was blocked by Cs+. The decreased period could also occur if the pump was inhibited with strophanthidin or K+-free saline. Our monensin results were reproduced in model, which explains the pump’s contributions to bursting activity based on Na+ dynamics. Our results indicate that a dynamically oscillating pump current that interacts with the h-current can regulate the bursting activity of neurons and networks. DOI: http://dx.doi.org/10.7554/eLife.19322.001 PMID:27588351

  9. The marine leech Stibarobdella loricata (Harding, 1924 (Hirudinea, Piscicolidae, parasitic on the angel shark Squatina spp. and sandtiger shark Carcharias taurus Rafinesque, 1810 (Chondrichthyes: Squatinidae, Carchariidae in Southern Brazilian waters

    Directory of Open Access Journals (Sweden)

    Soto J. M. R.

    2003-01-01

    Full Text Available The presence of the marine leech, Stibarobdella loricata (Harding, 1924 (Hirudinea, Piscicolidae, is reported on the southern coast of Brazil, based on seven lots with 47 specimens, between 71 and 182 mm in total length, collected on the dorsal region of angel sharks, Squatina argentina (Marini, 1930; S. guggenheim Marini, 1936; S. punctata Marini, 1936 (Chondrichthyes, Squatinidae; and on the head of a sandtiger shark, Carcharias taurus Rafinesque, 1810 (Chondrichthyes, Carchariidae. This is the first record of S. loricata in the western Atlantic and of its parasitic association with S. argentina, S. guggenheim, S. punctata, and C. taurus.

  10. Polar localization of plasma membrane Ca2+/Mg2+ ATPase correlates with the pattern of steady ionic currents in eggs ofLymnaea stagnalis andBithynia tentaculata (Mollusca).

    Science.gov (United States)

    Zivkovic, Danica; Créton, Robbert; Zwaan, Gideon; de Bruijn, Willem C; Dohmen, M René

    1990-11-01

    During extrusion of the first polar body in eggs ofLymnaea stagnalis andBithynia tentaculata a localized Ca 2+ /Mg 2+ ATPase activity was detected, using Ando's enzyme-cytochemical method for electron microscopy [Ando et al. (1981) Acta Histochem Cytochem 14:705-726]. The enzyme activity was distributed in a polar fashion, along the cytoplasmic face of the plasma membrane. In the eggs ofLymnaea it was found only in the vegetal hemisphere, whereas inBithynia eggs it was localized both in the vegetal hemisphere and at the animal pole. This pattern of enzyme activity corresponds to the polar pattern of transcellular ionic currents measured with the vibrating probe, which we showed to be partially carried or regulated by calcium [Zivkovic and Dohmen (1989) Biol Bull (Woods Hole) 176 (Suppl):103-109]. The characteristics of the ATPase were studied using a variety of approaches such as ion and substrate depletions and substitutions, addition of specific inhibitors of ATPase activity, treatment with EDTA/EGTA and electron energy-loss spectrometry. The results indicate that, inLymnaea, there are at least two enzymatic entities. The first one is a Ca 2+ /Mg 2+ ATPase localized along the membrane and in the cortex of the vegetal hemisphere. The second one is a Ca 2+ -stimulated ATPase (calcium pump of the plasma membrane) localized in a small region of the membrane at the vegetal pole. We speculate that in the eggs ofLymnaea andBithynia a functional relationship exists between the plasma-membrane-associated ATPase activity and the transcellular ionic currents measured in the same region.

  11. Occurrence of Hirudinea species in a post urban reach of a Patagonian mountain stream

    Directory of Open Access Journals (Sweden)

    M. Laura Miserendino

    2014-09-01

    Full Text Available Temporal (May 2005 to February 2006 and habitat distribution (pools and riffles of Hirudinea species was analyzed at a post urban reach from Esquel stream (Chubut province, Patagonia, Argentina. Site was located 5.7 km downstream a Waste Treatment Plant. Mean values of nutrients: ammonia, nitrates and soluble reactive phosphate, as well water conductivity, turbidity and total suspended solids indicated physical and organic pollution. Leeches assemblage was composed by the glossiphonids: Helobdella scutifera Blanchard, 1900, H. michaelseni (Blanchard, 1900, H. simplex (Moore, 1911, Helobdella sp., H. hyalina Ringuelet, 1942, H. obscura Ringuelet, 1942 and the semiscolecid Patagoniobdella variabilis (Blanchard, 1900. From these H. hyalina and H. obscura are new records for Chubut province. Helobdella hyalina (810 ind.m-2 and H. simplex (465 ind. m-2 clearly dominated the assemblage at the reach. Only H. simplex displayed a spatial preference being significantly more abundant in pools than in riffle habitats (p<0.001. Species recruitment occurred mostly at September, December and March when juveniles were very abundant. Although several species of Helobdella were able to live in the disturbed section of the stream, only H. simplex and H. hyalina sustained large populations at the site and can be considered as tolerant to organic enrichment. This information is valuable to future studies on stream condition assessment in mountainous areas in Patagonia, and in other areas in which these species are present.

  12. Marine leech Ozobranchus margoi parasitizing loggerhead turtle (Caretta caretta in Rio Grande do Sul, Brazil Sanguessugas Ozobranchus margoi parasitando uma tartaruga cabeçuda (Caretta caretta no Rio Grande do Sul, Brasil

    Directory of Open Access Journals (Sweden)

    Carla Rosane Rodenbusch

    2012-09-01

    Full Text Available This paper reports the finding of several Ozobranchus margoi (Annelida: Hirudinea parasitizing a loggerhead turtle (Caretta caretta that was found in the municipality of Tavares, state of Rio Grande do Sul, southern Brazil. Since this parasite is considered to be a vector of chelonid herpesvirus 5 (ChHV-5, the leeches collected were tested for the presence of this virus. All the specimens were negative on PCR analysis. Although O. margoi is considered to be a common sea turtle parasite, this is the first official record describing collection of this parasite from a loggerhead turtle in southern Brazil, within the country's subtropical zone. This finding draws attention to the presence of this parasite and to the risk of leech-borne infectious diseases among turtles found along the coast of southern Brazil.Este artigo relata a descoberta de vários exemplares de Ozobranchus margoi (Annelida Hirudínea parasitando uma tartaruga cabeçuda (Caretta caretta encontrada no município de Tavares, Rio Grande do Sul, sul do Brasil. Uma vez que esse parasito é considerado vetor do chelonid herpesvirus 5 (ChHV 5, as sanguessugas foram testadas para a presença deste vírus. Todas as amostras foram negativas pela análise de PCR. Embora o O. margoi seja considerado um parasito comum de tartarugas marinhas, este é o primeiro registro oficial que descreve a coleta deste parasita em uma tartaruga cabeçuda no sul do Brasil, dentro da zona subtropical do país. Este achado chama a atenção para a presença deste parasita e para o risco de sanguessugas transmitirem doenças infecciosas em tartarugas no litoral sul do Brasil.

  13. Experiências sôbre a transmissão do Trypanosoma cruzi por sanguessugas e de tripanosomas de vertebrados de sangue frio por triatomíneos Experiments of the transmission of Trypanosoma cruzi by leechs and cold blooded vertebrate trypanosomas by triatominae

    Directory of Open Access Journals (Sweden)

    Samuel B. Pessôa

    1969-06-01

    Full Text Available Observou-se que o Trypanosoma cruzi não se multiplica na sanguessuga (Haementeria lutzi Pinto; os tripanosomas sugados degeneram após algum tempo; outros permanecem aparentemente normais, porém 48 horas após a ingestão infectante acabam morrendo. Observou-se ainda que os tripanosomas parasitas da rã (T. rotatorium e T. leptodactyli bem como o T. hogei, parasita da serpente Rachidelus brazili, não se multiplicam no intestino dos triatomíneos. O mais resistente (o T. leptodactyli, permanece vivo até 72 horas após a ingestão infectante, porém as outras duas espécies (T. rotatorium e T. hogei não resistem mais de 24 horas após serem sugadas pelos triatomíneos.Trypanosoma cruzi does not reproduce itself in the leech (Haementerm lutzi Pinto; the ingested trypanosomes degenerate after some time; other organisms remain apparently normal, however dying 48 hours after the feeding of the leechs. The parasite trypanosomas of the frog (T. rotatorium and T. leptodactyli as well as those parasiting the ophidian Rachidelus brazili (T. hogei do not multiply in the intestine of the triatominae. The most resistent species (T. leptocbactyli remains alive 72 hours after the feeding of the triatominae; the other two, however, do not survive more than 24 hours.

  14. 'Infantile convulsions' in the early nineteenth century. Abnormal brain blood flow and leeches, teething and gums' scarification and food and purgatives: the historical contribution of John Clarke (1760-1815).

    Science.gov (United States)

    Brigo, Francesco; Lattanzi, Simona; Trinka, Eugen; Nardone, Raffaele; Bragazzi, Nicola Luigi; Ruggieri, Martino; Vecchio, Ignazio; Martini, Mariano

    2018-03-20

    In this article, we discuss on the role of the British physician and midwifery practitioner John Clarke (1760-1815) in the characterisation of the various types of seizures and epilepsy and related phenomena ('convulsions') occurring in children. In his unfinished work Commentaries on Some of the Most Important Diseases of Children (1815), Clarke discussed the pathophysiology of convulsions and was the first to describe, 12 years before the French neurologist Louis Francois Bravais (1801-1843) and more than 30 years before the Irish-born physician Robert Bentley Todd (1809-1860), the postictal paresis. He believed that convulsions originated from changes in pressure within the ventricles as a consequence of abnormal blood flow to the cerebral vessels. In keeping with the theories of his time (e.g. Baumes 1789, 1805; Brachet 1824), Clarke believed that teething was a major cause of 'infantile convulsions'. His proposed remedies ranged from scarification of the gums to ammonia, application of leeches, cold water, and purgatives. The use of antispasmodics, quite popular at the time, was instead questioned. In his Practical Observations on the Convulsions of Infants (1826), the London practitioner and midwifery John North (1790-1873) deeply criticised Clarke's view that convulsions arise inevitably as a consequence of organic brain lesions. North inferred that the results of autopsies of children who had died of convulsions revealed no brain damages, and claimed that cerebral irritation could also occur as the effect of distant lesions. Other Clarke's contemporaries (e.g. Jean Baptiste Timothée Baumes-1756-1828) inferred that all convulsions reflected a hereditary diathesis, which rendered children (especially those with softer and limper nervous and muscular tissues!) extremely sensitive to all sorts of provocation that could trigger convulsions, including bad digestion (more pronounced at the time of teething), loud noise, and bright light. Although almost every

  15. Duration of sperm storage in the simultaneous hermaphrodite Lymnaea stagnalis

    NARCIS (Netherlands)

    Nakadera, Y.; Blom, C.; Koene, J.M.

    2014-01-01

    Reproductive success is a crucial variable to understand the action of sexual selection, but its quantification is not straightforward because several factors cause nonrandom fertilization success. One of these factors is female sperm storage, which leads to prolonged paternity gain (paternity

  16. Leech as a cause of abnormal vaginal bleeding: Presentation of ...

    African Journals Online (AJOL)

    JOURNAL OF ERITREAN MEDICAL ASSOCIATION JEMA. 59. Introduction ... days, menstrual cycle of <21 days and total menstrual ... were being used as a means of blood letting, a practice ... normal vital signs and a slightly pale conjunctiva.

  17. Case Report: Positive outcome of medical leeches (hirudotherapy ...

    African Journals Online (AJOL)

    been treated for several years for chronic superficial venous insufficiency ... on the left leg. Figure 2: Round-oval erythematous plaques centered by small ulceration ... Psychological impact can be significant and might push cessation of the.

  18. Triassic leech cocoon from Antarctica contains fossil bell animal

    DEFF Research Database (Denmark)

    Bomfleur, Benjamin; Kerp, Hans; Taylor, Thomas N.

    2012-01-01

    . The microfossil consists of a helically contractile stalk that attaches to a main body with a peristomial feeding apparatus and a large C-shaped macronucleus. It agrees in every aspect with the living bell animals, such as Vorticella. Vorticellids and similar peritrichs are vital constituents of aquatic...... ecosystems worldwide, but so far have lacked any fossil record. This discovery offers a glimpse of ancient soft-bodied protozoan biotas, and also highlights the potential of clitellate cocoons as microscopic "conservation traps" comparable to amber....

  19. of Geoffrey Leech's Semantics: the Study of Meaning

    African Journals Online (AJOL)

    ings of units of form (e.g. 'words'), together with rules governing the semantic ... who has before him Harrap's French-English, English-French dictionary as his sale ..... The second distinction is between 'conceptual' ('literal ') and other kinds of ...

  20. Gene expression program of regeneration in Eisenia fetida: a transcriptomics study

    Directory of Open Access Journals (Sweden)

    Aksheev Bhambri

    2017-10-01

    Full Text Available Annelids form a connecting link between segmented and non-segmented organisms.  In other words, phylogenetically, the segmented body pattern starts from Annelida, a phylum that consists of thousands of species, including marine worms, freshwater leeches and earthworms that inhabit deep layers of soil to environmental niches in forests and cultivated land. We are using Eisenia fetida (Indian isolate a top dwelling, vermicomposting worm due to its ability to regenerate its posterior after damage, injury or complete removal. On average, Eisenia fetida has 100-110 segments. We separated the anterior (upto 55-60th segment and posterior of the worm, and allowed it to regenerate.  In this model, only the posterior could be regenerated after injury.  We isolated RNA from the regenerated tissue and the immediate adjacent old tissue at 15 days, 20 days and 30 days during regeneration. We carried out transcriptome sequencing and analysis. With the aim of identifying specific factors which promote nerve regeneration, we have annotated the differentially expressed genes. In all organisms which possess a segmented body, the expression pattern of the Hox cluster is conserved. Hox gene expression, a conserved developmental phenomenon in establishment of body plan has been studied by comparative genomics of other annelids like the marine worm Capitella telleta, the leech Helobdella robusta.  We have used a combination of high-throughput sequencing based techniques and validation through cell and molecular biology to identify key aspects of the gene expression program of regeneration in this worm. Besides the transcriptome, we have also done whole genome sequencing, miRnome and metagenome sequencing of this terrestrial annelid.

  1. High voltage with little current as an unconditional stimulus for taste avoidance conditioning in Lymnaea stagnalis.

    Science.gov (United States)

    Takigami, Satoshi; Sunada, Hiroshi; Lukowiak, Ken; Sakakibara, Manabu

    2013-10-25

    A new and better taste avoidance conditioning paradigm for Lymnaea has been developed that replaces the previously used tactile unconditional stimulus (US) with an brief electrical stimulus (1000V, 80μA), while continuing to use a sucrose application to the lips as the conditional stimulus (CS). With 15 paired CS-US presentations on a single day, we were able to elicit both short-term memory (STM) and long-term memory (LTM). The LTM persisted for at least one week. While STM was elicited with 5, 8, or 10 paired presentations of the CS-US on a single day, LTM was not. The new US used here was more consistent than the previously used US, and this stimulus consistency may explain why 15 paired CS-US presentations now result in LTM formation. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  2. Critical period of memory enhancement during taste avoidance conditioning in Lymnaea stagnalis.

    Science.gov (United States)

    Takahashi, Tomoyo; Takigami, Satoshi; Sunada, Hiroshi; Lukowiak, Ken; Sakakibara, Manabu

    2013-01-01

    The present study investigated the optimal training procedure leading to long-lasting taste avoidance behavior in Lymnaea. A training procedure comprising 5 repeated pairings of a conditional stimulus (CS, sucrose), with an unconditional stimulus (US, a tactile stimulation to the animal's head), over a 4-day period resulted in an enhanced memory formation than 10 CS-US repeated pairings over a 2-day period or 20 CS-US repeated pairings on a single day. Backward conditioning (US-CS) pairings did not result in conditioning. Thus, this taste avoidance conditioning was CS-US pairing specific. Food avoidance behavior was not observed following training, however, if snails were immediately subjected to a cold-block (4°C for 10 min). It was critical that the cold-block be applied within 10 min to block long-term memory (LTM) formation. Further, exposure to the cold-block 180 min after training also blocked both STM and LTM formation. The effects of the cold-block on subsequent learning and memory formation were also examined. We found no long lasting effects of the cold-block on subsequent memory formation. If protein kinase C was activated before the conditioning paradigm, snails could still acquire STM despite exposure to the cold-block.

  3. Reproductive impacts of tributyltin (TBT) and triphenyltin (TPT) in the hermaphroditic freshwater gastropod Lymnaea stagnalis

    OpenAIRE

    Giusti, Arnaud; Barsi, Alpar; Dugue, Mael; Collinet, Marc; Thome, Jean-Pierre; Joaquim-Justo, Celia; Roig, Benoit; Lagadic, Laurent; Ducrot, Virginie

    2013-01-01

    Tributyltin (TBT) and triphenyltin (TPT) are emblematic endocrine disruptors, which have been mostly studied in gonochoric prosobranchs. Although both compounds can simultaneously occur in the environment, they have mainly been tested separately for their effects on snail reproduction. Because large discrepancies in experimental conditions occurred in these tests, the present study aimed at comparing the relative toxicity of TBT and TPT under similar laboratory conditions in the 0–600 ng Sn/L...

  4. Transgenerational endpoints provide increased sensitivity and insight into multigenerational responses of Lymnaea stagnalis exposed to cadmium.

    Science.gov (United States)

    Reátegui-Zirena, Evelyn G; Fidder, Bridgette N; Olson, Adric D; Dawson, Daniel E; Bilbo, Thomas R; Salice, Christopher J

    2017-05-01

    Ecotoxicology provides data to inform environmental management. Many testing protocols do not consider offspring fitness and toxicant sensitivity. Cadmium (Cd) is a well-studied and ubiquitous toxicant but little is known about the effects on offspring of exposed parents (transgenerational effects). This study had three objectives: to identify endpoints related to offspring performance; to determine whether parental effects would manifest as a change in Cd tolerance in offspring and how parental exposure duration influenced the manifestation of parental effects. Adult snails were exposed to Cd 0, 25, 50, 100, 200 and 400 μg Cd/L for eight weeks. There were effects on adult endpoints (e.g., growth, reproduction) but only at the highest concentrations (>100 μg/L). Alternatively, we observed significant transgenerational effects at all Cd concentrations. Surprisingly, we found increased Cd tolerance in hatchlings from all parental Cd exposure concentrations even though eggs and hatchlings were in Cd-free conditions for 6 weeks. Explicit consideration of offspring performance adds value to current toxicity testing protocols. Parental exposure duration has important implications for offspring effects and that contaminant concentrations that are not directly toxic to parents can cause transgenerational changes in resistance that have significant implications for toxicity testing and adaptive responses. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Mating rate influences female reproductive investment in a simultaneous hermaphrodite, Lymnaea stagnalis.

    NARCIS (Netherlands)

    Hoffer, J.N.A.; Schwegler, D.; Ellers, J.; Koene, J.M.

    2012-01-01

    Multiple mating often imposes direct fitness costs on females but can provide indirect benefits such as enhanced genetic diversity and offspring quality. The costs and benefits of multiple mating have been investigated extensively in separate-sex species but less so in simultaneous hermaphrodites,

  6. Critical period of memory enhancement during taste avoidance conditioning in Lymnaea stagnalis.

    Directory of Open Access Journals (Sweden)

    Tomoyo Takahashi

    Full Text Available The present study investigated the optimal training procedure leading to long-lasting taste avoidance behavior in Lymnaea. A training procedure comprising 5 repeated pairings of a conditional stimulus (CS, sucrose, with an unconditional stimulus (US, a tactile stimulation to the animal's head, over a 4-day period resulted in an enhanced memory formation than 10 CS-US repeated pairings over a 2-day period or 20 CS-US repeated pairings on a single day. Backward conditioning (US-CS pairings did not result in conditioning. Thus, this taste avoidance conditioning was CS-US pairing specific. Food avoidance behavior was not observed following training, however, if snails were immediately subjected to a cold-block (4°C for 10 min. It was critical that the cold-block be applied within 10 min to block long-term memory (LTM formation. Further, exposure to the cold-block 180 min after training also blocked both STM and LTM formation. The effects of the cold-block on subsequent learning and memory formation were also examined. We found no long lasting effects of the cold-block on subsequent memory formation. If protein kinase C was activated before the conditioning paradigm, snails could still acquire STM despite exposure to the cold-block.

  7. Statistical refinements for data analysis of mollusc reproduction tests: an example with Lymnaea stagnalis

    DEFF Research Database (Denmark)

    Holbech, Henrik

    -contribution of each individual to the measured response. Furthermore, the combination of a Gamma-Poisson stochastic part with a Weibull concentration-response model allowed accounting for the inter-replicate variability. Second, we checked for the possibility of optimizing the initial experimental design through...... was twofold. First, we refined the statistical analyses of reproduction data accounting for mortality all along the test period. The variable “number of clutches/eggs produced per individual-day” was used for EC x modelling, as classically done in epidemiology in order to account for the time...

  8. Insights into bilaterian evolution from three spiralian genomes

    Energy Technology Data Exchange (ETDEWEB)

    Simakov, Oleg; Marletaz, Ferdinand; Cho, Sung-Jin; Edsinger-Gonzales, Eric; Havlak, Paul; Hellsten, Uffe; Kuo, Dian-Han; Larsson, Tomas; Lv, Jie; Arendt, Detlev; Savage, Robert; Osoegawa, Kazutoyo; de Jong, Pieter; Grimwood, Jane; Chapman, Jarrod A.; Shapiro, Harris; Otillar, Robert P.; Terry, Astrid Y.; Boore, Jeffrey L.; Grigoriev, Igor V.; Lindberg, David R.; Seaver, Elaine C.; Weisblat, David A.; Putnam, Nicholas H.; Rokhsar, Daniel S.; Aerts, Andrea

    2012-01-07

    Current genomic perspectives on animal diversity neglect two prominent phyla, the molluscs and annelids, that together account for nearly one-third of known marine species and are important both ecologically and as experimental systems in classical embryology1, 2, 3. Here we describe the draft genomes of the owl limpet (Lottia gigantea), a marine polychaete (Capitella teleta) and a freshwater leech (Helobdella robusta), and compare them with other animal genomes to investigate the origin and diversification of bilaterians from a genomic perspective. We find that the genome organization, gene structure and functional content of these species are more similar to those of some invertebrate deuterostome genomes (for example, amphioxus and sea urchin) than those of other protostomes that have been sequenced to date (flies, nematodes and flatworms). The conservation of these genomic features enables us to expand the inventory of genes present in the last common bilaterian ancestor, establish the tripartite diversification of bilaterians using multiple genomic characteristics and identify ancient conserved long- and short-range genetic linkages across metazoans. Superimposed on this broadly conserved pan-bilaterian background we find examples of lineage-specific genome evolution, including varying rates of rearrangement, intron gain and loss, expansions and contractions of gene families, and the evolution of clade-specific genes that produce the unique content of each genome.

  9. Cytogenetic and morphophysiological differences in snail Lymnaea stagnalis (Gastropoda, Pulmonata) from reservoirs of the Chernobyl NPP resettling zone

    International Nuclear Information System (INIS)

    Koneva, A.Yu.; Afonin, V.Yu.; Dramashka, S.Ya.; Golubew, A.P.

    2006-01-01

    A cytogenetic analysis of the molluscs obtained from animals of two populations of the Chernobyl NPP zone was carried out. Preservation of the raised number of cells with micronuclei in hemolymph of the molluscs obtained from animals lived under conditions with the highest level of radiation contamination was noted. Interpopulational distinctions in a number of biological parameters were revealed. Away of fertilization which is used for animal production under laboratory conditions affects sensitivity of molluscs to additional acute irradiation was established. (authors)

  10. The Early Worm Catches the Bird? Productivity and Patterns of Trichobilharzia szidati Cercarial Emission from Lymnaea stagnalis

    Czech Academy of Sciences Publication Activity Database

    Soldánová, Miroslava; Selbach, C.; Sures, B.

    2016-01-01

    Roč. 11, č. 2 (2016), č. článku e0149678. E-ISSN 1932-6203 R&D Projects: GA ČR GA15-14198S Institutional support: RVO:60077344 Keywords : living endohelminth stages * Diplostomum spathaceum * Schistosoma mansoni Subject RIV: EG - Zoology Impact factor: 2.806, year: 2016

  11. [Ultrastructural changes in the MP3 neuron of the mollusk Lymnaea stagnalis after cryopreservation of the isolated brain].

    Science.gov (United States)

    Dmitrieva, E V; Moshkov, D A; Gakhova, E N

    2006-01-01

    Investigation of a possibility of long-term storage of frozen (-196 degrees C) viable neurons and nervous tissue is one of the central present day problems. In this study ultrastructural changes in neurons of frozen-thawed snail brain were examined as a function of time. We studied the influence of cryopreservation, cryoprotectant (Me2SO), cooling to 4-6 degrees C, and a prolonged incubation in physiological solution at 4-6 degrees C on dictyosomes of Golgi apparatus, endoplasmic reticulum (ER) cisternae and mitochondria. It has been found that responses of these intracellular structures of cryopreserved neurons to the above influences are similar: dissociation of Golgi dictyosomes, swelling of endoplasmic reticulum cisternae and mitochondrial cristae. Both freezing-thawing and cryoprotectant were seen to cause an increase in the number of lysosomes, liposomes, myelin-like structures, and to form large vacuoles. The structural changes in molluscan neurons caused by cryopreservation with Me2SO (2 M) were reversible.

  12. The propensity to bi-stability of bursting and silence of the leech heart interneuron

    Science.gov (United States)

    Malaschenko, Tatiana; Williams, Diana; Shilnikov, Andrey; Cymbalyuk, Gennady

    2009-11-01

    Bursting is one of primary activity regimes of neurons. Our previous study was focused on determining a generic biophysical mechanism underlying the transition between bursting and silence and the co-existence of these two regimes observed in a neuron model. We show that this co-existence can be explained by the unstable sub-threshold oscillations (USTO) separating silence and bursting. The range of the controlling parameters, where the co-existence is observed, is limited by the critical values of the system at which the Andronov-Hopf and homoclinic bifurcations occur. We investigate how different parameters of the model affect the width of the co-existence area. We study the effects of the variations of maximal conductances of every voltage-dependent current. The influence of each current was tested individually, one at the time. We found that only two of them had a significant effect on the range of co-existence. The increase of the maximal conductance of the hyperpolarization-activated cationic current Ih would expand the area of co-existence. The decrease of the conductance of the LVA fast Ca^2+ current has the opposite effect.

  13. Bistability of bursting and silence regimes in a model of a leech heart interneuron

    Science.gov (United States)

    Malashchenko, Tatiana; Shilnikov, Andrey; Cymbalyuk, Gennady

    2011-10-01

    Bursting is one of the primary activity regimes of neurons. Our study is focused on determining a generic biophysical mechanism underlying the coexistence of the bursting and silent regimes observed in a neuron model. We show that the main ingredient for this mechanism is a saddle periodic orbit. The stable manifold of the orbit sets a threshold between the regimes of activity. Thus, the range of the controlling parameters, where the coexistence is observed, is limited by the bifurcations' values at which the saddle orbit appears and disappears. We show that it appears through the subcritical Andronov-Hopf bifurcation, where the equilibrium representing the silent regime loses stability, and disappears at the homoclinic bifurcation. Correspondingly, the bursting regime disappears in close proximity to the homoclinic bifurcation.

  14. The Chameleon as a Leech: The Costs of Mimicry for the Mimickee

    Directory of Open Access Journals (Sweden)

    Kot Sylwia

    2016-04-01

    Full Text Available Mimicry is known to produce benefits for the mimicker such as liking, increased prosocial tendencies (e.g., higher donations, and trust. Little is known about the benefits or costs to the mimickee. The aim of this study is to explore this issue. Participants were mimicked or not by a confederate. The confederate then dropped pens and checked if the participants picked them up (a proxy for prosocial behavior. Finally, questionnaires were administered that assessed each participant’s liking of the confederate and self-liking, and self-esteem. As expected, mimicked participants picked up more pens and liked the mimicker more. Surprisingly, mimicked participants reported significantly lower self-like when compared to non-mimicked participants, and their self-esteem tended towards being lower. This research fills an important theoretical gap showing that there is a great cost to mimicry.

  15. ANATOMY, LIFE HISTORY AND DISTRIBUTION OF THE PARASITIC LEECH OLIGOBDELLA BIANNULATA (MOORE, 1900) (EUHIRUDINEA: GLOSSIPHONIIDAE)

    Science.gov (United States)

    Oligobdella biannulata (Moore, 1900) is a rare, endemic species originally described from a mountain stream near Blowing Rock, North Carolina. Specimens of this species were collected seasonally from fall 1999 to winter 2001 with four new county records in North Carolina (Avery,...

  16. From leeches to personalized medicine: evolving concepts in the management of polycythemia vera

    Science.gov (United States)

    Vannucchi, Alessandro M.

    2017-01-01

    Polycythemia vera is a clonal disorder of hematopoietic stem/progenitor cells. It manifests as an expansion of red cell mass. It is the most common chronic myeloproliferative neoplasm. In virtually all cases, it is characterized by a V617F point mutation in JAK2 exon 14 or less common mutations in exon 12. The landmark discovery of the autonomously activated JAK/STAT signaling pathway paved the way for the clinical development of the first target drug, the JAK1 and JAK2 inhibitor ruxolitinib. This is now approved for patients with resistance or intolerance to hydroxyurea. Phlebotomies and hydroxyurea are still the cornerstone of treatment, and aim to prevent the first appearance or recurrence of cardiovascular events that, together with progression to post-polycythemia vera myelofibrosis and leukemia, represent the main causes of death. Interferon-α is an alternative drug and has been shown to induce molecular remissions. It is currently undergoing phase III trials that might eventually lead to its approval for clinical use. The last few years have witnessed important advances towards an accurate early diagnosis of polycythemia vera, greater understanding of its pathogenesis, and improved patient management. This review will focus on the most recent achievements and will aim to unify the different concepts involved in a personalized approach to the patient with polycythemia vera. In spite of many recent advances in the understanding of its pathogenesis and improved disease management, polycythemia vera remains a life-threatening myeloproliferative neoplasm for which there is no cure. This review will present a critical overview of evolving concepts in diagnosis and treatment of this disease. PMID:27884974

  17. Rediscovery of the Empress, Sasakia funebris Leech (Lepidoptera: Nymphalidae: Nymphalinae: Apaturini after 88 years in India

    Directory of Open Access Journals (Sweden)

    A.P. Singh

    2013-06-01

    Full Text Available The sighting of an Empress, Sasakia funebris, is reported from upper Debang Valley District, Arunachal Pradesh. This is the first record of this butterfly after almost nine decades in India. Observations on the habitat and habits of the species are given.

  18. Predatory leeches (Hirudinida) may contribute to amphibian declines in the Lassen, California.

    Science.gov (United States)

    Stead Jonathan; Karen Pope

    2010-01-01

    Researchers have documented precipitous declines in Cascades Frog (Rana cascadae) populations in the southern portion of the species' range, in the Lassen region of California. Reasons for the declines, however, have not been elucidated. In addition to common, widespread causes, an understanding of local community interactions may be necessary...

  19. A study on nutrition of medicinal leech (Hirudo verbana Carena, 1820: Cannibalism?.

    Directory of Open Access Journals (Sweden)

    Mustafa Ceylan

    2015-12-01

    Full Text Available Bu çalışma ile tıbbi sülük Hirudo verbana’nın yapay koşullarda beslenme esnası ve sonrası davranışlarının araştırılması amaçlanmıştır. Sülükler taze sığır kanı ile beslenmişlerdir ve toplu tartım yöntemiyle beslenme sonrasında %97.74 oranında ağırlık artışı olmuştur. Yeteri kadar beslenememiş bazı sülüklerin, hareket kabiliyetlerini kısmen kaybetmiş olan bazı tok sülüklere saldırdıkları, kanibalistik eğilim sergiledikleri, ancak kanibalizmin net olarak şekillenmediği görülmüştür. Bazı sülüklerin beslenmeden 66. gün sonrasında dahi tükettikleri kanın bir kısmını kustukları görülmüştür. Kusulan kanın bazı bireylerin uyarımına neden olduğu, ancak kanın bulunduğu bölgeye gelen sülüklerin kısa süreli bir incelemenin ardından kana ilgisiz davrandıkları ve bölgeden uzaklaştıkları gözlenmiştir. Yetiştiricilik şartlarında periyodik besleme gruplarının oluşturulması, tüm sülüklerin uyarılarak beslenmeye hazır hale gelmeleri ve beslenme sonrasında tok ile yeterince beslenmemiş bireylerin ayrı ortamlara alınmaları ile tıbbi sülük H. verbana’da potansiyel kanibalizm eğiliminden kaynaklı problemlerin önüne geçilebileceği düşünülmektedir

  20. Infection, specificity and host manipulation of Australapatemon sp (Trematoda, Strigeidae) in two sympatric species of leeches (Hirudinea)

    Czech Academy of Sciences Publication Activity Database

    Karvonen, A.; Faltýnková, Anna; Choo, J. M.; Valtonen, E. T.

    2017-01-01

    Roč. 144, č. 10 (2017), s. 1346-1355 ISSN 0031-1820 Institutional support: RVO:60077344 Keywords : complex life cycle * Digenea * host manipulation * host-parasite relationship * spatiotemporal variation * specificity * Trematoda Subject RIV: EG - Zoology OBOR OECD: Zoology Impact factor: 2.713, year: 2016

  1. THE LEECH EXOPLANET IMAGING SURVEY: ORBIT AND COMPONENT MASSES OF THE INTERMEDIATE-AGE, LATE-TYPE BINARY NO UMa

    Energy Technology Data Exchange (ETDEWEB)

    Schlieder, Joshua E. [NASA Ames Research Center, Space Science and Astrobiology Division, MS 245-6, Moffett Field, CA 94035 (United States); Skemer, Andrew J.; Hinz, Philip; Leisenring, Jarron; Defrère, Denis; Close, Laird M.; Eisner, Josh A. [Steward Observatory, Department of Astronomy, University of Arizona, 933 N. Cherry Avenue, Tucson, AZ 85721 (United States); Maire, Anne-Lise; Desidera, Silvano [INAF—Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, I-35122, Padova (Italy); Skrutskie, Michael F. [Department of Astronomy, University of Virginia, Charlottesville, VA, 22904 (United States); Bailey, Vanessa [Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, Stanford, CA 94305 (United States); Esposito, Simone [INAF—Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50125, Firenze (Italy); Strassmeier, Klaus G.; Weber, Michael [Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16, D-14482, Potsdam (Germany); Biller, Beth A.; Bonnefoy, Mickaël; Buenzli, Esther; Henning, Thomas [Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117, Heidelberg (Germany); Crepp, Justin R. [Department of Physics, University of Notre Dame, 225 Nieuwland Science Hall, Notre Dame, IN, 46556 (United States); Hofmann, Karl-Heinz, E-mail: joshua.e.schlieder@nasa.gov [Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121, Bonn (Germany); and others

    2016-02-10

    We present high-resolution Large Binocular Telescope LBTI/LMIRcam images of the spectroscopic and astrometric binary NO UMa obtained as part of the LBT Interferometer Exozodi Exoplanet Common Hunt exoplanet imaging survey. Our H-, K{sub s}-, and L′-band observations resolve the system at angular separations <0.″09. The components exhibit significant orbital motion over a span of ∼7 months. We combine our imaging data with archival images, published speckle interferometry measurements, and existing spectroscopic velocity data to solve the full orbital solution and estimate component masses. The masses of the K2.0 ± 0.5 primary and K6.5 ± 0.5 secondary are 0.83 ± 0.02 M{sub ⊙} and 0.64 ± 0.02 M{sub ⊙}, respectively. We also derive a system distance of d = 25.87 ± 0.02 pc and revise the Galactic kinematics of NO UMa. Our revised Galactic kinematics confirm NO UMa as a nuclear member of the ∼500 Myr old Ursa Major moving group, and it is thus a mass and age benchmark. We compare the masses of the NO UMa binary components to those predicted by five sets of stellar evolution models at the age of the Ursa Major group. We find excellent agreement between our measured masses and model predictions with little systematic scatter between the models. NO UMa joins the short list of nearby, bright, late-type binaries having known ages and fully characterized orbits.

  2. New Insights to Compare and Choose TKTD Models for Survival Based on an Interlaboratory Study for Lymnaea stagnalis Exposed to Cd.

    Science.gov (United States)

    Baudrot, Virgile; Preux, Sara; Ducrot, Virginie; Pave, Alain; Charles, Sandrine

    2018-02-06

    Toxicokinetic-toxicodynamic (TKTD) models, as the General Unified Threshold model of Survival (GUTS), provide a consistent process-based framework compared to classical dose-response models to analyze both time and concentration-dependent data sets. However, the extent to which GUTS models (Stochastic Death (SD) and Individual Tolerance (IT)) lead to a better fitting than classical dose-response model at a given target time (TT) has poorly been investigated. Our paper highlights that GUTS estimates are generally more conservative and have a reduced uncertainty through smaller credible intervals for the studied data sets than classical TT approaches. Also, GUTS models enable estimating any x% lethal concentration at any time (LC x,t ), and provide biological information on the internal processes occurring during the experiments. While both GUTS-SD and GUTS-IT models outcompete classical TT approaches, choosing one preferentially to the other is still challenging. Indeed, the estimates of survival rate over time and LC x,t are very close between both models, but our study also points out that the joint posterior distributions of SD model parameters are sometimes bimodal, while two parameters of the IT model seems strongly correlated. Therefore, the selection between these two models has to be supported by the experimental design and the biological objectives, and this paper provides some insights to drive this choice.

  3. Considerations for test design to accommodate energy-budget models in ecotoxicology: a case study for acetone in the pond snail lymnaea stagnalis.

    NARCIS (Netherlands)

    Barsi, A.; Jager, T.; Collinet, M.; Lagadic, L.; Ducrot, V.

    2014-01-01

    Toxicokinetic-toxicodynamic (TKTD) modeling offers many advantages in the analysis of ecotoxicity test data. Calibration of TKTD models, however, places different demands on test design compared with classical concentration-response approaches. In the present study, useful complementary information

  4. The Role of Spatial and Temporal Heterogeneity and Competition In Structuring Trematode Communities In the Great Pond Snail, Lymnaea stagnalis (L.)

    Czech Academy of Sciences Publication Activity Database

    Soldánová, Miroslava; Kuris, A. M.; Scholz, Tomáš; Lafferty, K. D.

    2012-01-01

    Roč. 98, č. 3 (2012), s. 460-471 ISSN 0022-3395 R&D Projects: GA ČR GAP505/10/1562; GA ČR GD206/09/H026; GA MŠk LC522 Institutional research plan: CEZ:AV0Z60220518 Keywords : LARVAL TREMATODES * HELISOMA-ANCEPS * INTERSPECIFIC INTERACTIONS * DIPLOSTOMUM-SPATHACEUM * CENTRAL-EUROPE * ANTAGONISM * PARASITES * HOST * PATTERNS * DYNAMICS Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 1.321, year: 2012

  5. Accumulation and detoxication responses of the gastropod Lymnaea stagnalis to single and combined exposures to natural (cyanobacteria) and anthropogenic (the herbicide RoundUp® Flash) stressors

    DEFF Research Database (Denmark)

    Lance, Emilie; Desprat, J.; Holbech, B. F.

    2016-01-01

    , and ii) activities of anti-oxidant (catalase CAT) and biotransformation (glutathione-S-transferase GST) enzymes. During the intoxication, the cyanobacterial exposure induced an early increase of CAT activity, independently of the MC content, probably related to the production of secondary cyanobacterial...

  6. Suckers for Science.

    Science.gov (United States)

    Haugen, Heidi Helene

    2001-01-01

    Introduces an inquiry-based program on leeches that features five components: (1) engagement; (2) exploration; (3) explanation; (4) evaluation; and (5) extension/elaboration. Investigates the anatomy and environmental conditions of leeches. (YDS)

  7. Case report of oral cavity infestation in a 3-year old jackass with Limnatis nilotica from Ilam province, west of Iran

    Directory of Open Access Journals (Sweden)

    Mahmoud Bahmani

    2014-06-01

    Full Text Available Leeches (phylum: Annelida, class: hirudinea could infest wide range of livestock such as cow, buffalo, sheep, goat, horse, mule, ass, dog, pig and even human. In November 2013, a 3-year old jackass from Dehloran county, Ilam province, Iran, was infected through his mouth due to drinking spring water. Symptoms including stress, anxiety and tachycardia were seen. After examining oral cavity of jackass, a leech was observed in upper gum. The leech was measured after separation which was three inches in length. The leech was adult which has dark green with orange lines, and it was identified as Limnatis nilotica species. It seems that using spring, subterranean water, pond etc. is the main causes of livestock infestation with leech. Ranchers could be recommended to decontaminate leech waters to prevent further leech infestation cases.

  8. A new leech species of Semiscolex (Arhynchobdellida: Semiscolecidae from Lake Catemaco, Veracruz, Mexico Especie nueva de sanguijuela del género Semiscolex (Arhynchobdellida: Semiscolecidae del lago de Catemaco, Veracruz, México

    Directory of Open Access Journals (Sweden)

    Alejandro Oceguera-Figueroa

    2006-12-01

    Full Text Available Semiscolex lamothei sp. nov. from Catemaco lake, Veracruz, México, is described based on the examination of 18 specimens. The new species differs from other species of the genus by the presence of 1/2 + 5 + 1/2 annuli between gonopores. The new species has morphological features previously not described for any other member of the genus, such as well-developed ejaculatory bulbs and postcaeca in the posterior part of the crop. This is the first record of the genus and the family in the northern hemisphere of the Americas.Se describe Semiscolex lamothei sp. nov. del lago de Catemaco, Veracruz, México con base en 18 ejemplares. Se diferencia del resto de las especies del género por presentar 1/2 + 5 + 1/2 anillos entre los gonoporos. Esta nueva especie del género Semiscolex presenta características morfológicas no descritas en otros miembros del grupo, como bulbos eyaculadores bien desarrollados y postciegos en la región terminal del buche. Es el primer registro del género y de la familia en el hemisferio norte del continente americano.

  9. A new leech species of Semiscolex (Arhynchobdellida: Semiscolecidae) from Lake Catemaco, Veracruz, Mexico Especie nueva de sanguijuela del género Semiscolex (Arhynchobdellida: Semiscolecidae) del lago de Catemaco, Veracruz, México

    OpenAIRE

    Alejandro Oceguera-Figueroa

    2006-01-01

    Semiscolex lamothei sp. nov. from Catemaco lake, Veracruz, México, is described based on the examination of 18 specimens. The new species differs from other species of the genus by the presence of 1/2 + 5 + 1/2 annuli between gonopores. The new species has morphological features previously not described for any other member of the genus, such as well-developed ejaculatory bulbs and postcaeca in the posterior part of the crop. This is the first record of the genus and the family in the norther...

  10. Genetics and morphology of the genus Tritetrabdella (Hirudinea, Haemadipsidae) from the mountainous rain forests of Sabah, Borneo, reveal a new species with two new subspecies

    NARCIS (Netherlands)

    Kappes, H.

    2013-01-01

    Blood-feeding terrestrial leeches of the family Haemadipsidae are a notorious part of the invertebrate diversity in Asian and Australian rain forests. All hitherto published records of terrestrial leeches of Borneo belong to the genus Haemadipsa. Here, a second, poorly known haemadipsid genus is

  11. Voelt de medicinale bloedzuiger Hirudo medicinalis zich wel zo lekker in Nederland (Hirudinea)?

    NARCIS (Netherlands)

    Felix, R.P.W.H.; Velde, van der G.

    2000-01-01

    Does the medicinal leech Hirudo medicinalis feel well in the Netherlands (Hirudinea)? This paper provides information on the medicinal leech Hirudo medicinalis Linnaeus, 1758 particularly in The Netherlands. Although this species was common in The Netherlands in the 18th century, nowadays it is very

  12. The persistence of hepatitis B antigen in the bloodmeal of the ...

    African Journals Online (AJOL)

    The results are compared with reports on other arthropods which indicate increasing antigen persistence with increasing body size. The findings implicate medicinal leeches as mechanical vectors of HBV and possibly of other medically important viruses, and argue against using leeches of suspect or unknown origin in the ...

  13. Naragh Suburb, Center of Iran; A Natural Habitat of Hirudo medicinalis

    Directory of Open Access Journals (Sweden)

    Dehghani R.1 PhD,

    2014-08-01

    Full Text Available Aims A very common species of leeches has been named as Hirudo medicinalis. Regarding to the application of leeches in medicine and their fast extinction, this study was performed in aquatic habitats of Kashan aimed to determine the distribution of leeches and to provide information about their regional and habitat characteristics. Materials & Methods This descriptive study was conducted during 2008 to 2010 in three periods and 90 samples from 30 sites were collected, totally. 30 lentic and lotic aquatic habitats located in different regions of Naragh were recognized and selected. Leeches were collected initially in 10% ethanol followed by washing and removing mucus and then maintained in 70% ethanol. The identification keys were used for recognizing the species of leeches. Findings According to the identification key of the leech species, 15 samples from the total samples of 30 locations were Hirudo medicinalis. Total Hirudo medicinalis samples were collected just from Naragh River. These species of leeches were relatively large with 7-10cm and their colors were olive green, brown and greenish brown with a red stripe on the sides. Conclusion Naragh River is one of the habitats of Hirudo medicinalis.

  14. Nickel toxicity to benthic organisms: The role of dissolved organic carbon, suspended solids, and route of exposure.

    Science.gov (United States)

    Custer, Kevin W; Hammerschmidt, Chad R; Burton, G Allen

    2016-01-01

    Nickel bioavailability is reduced in the presence of dissolved organic carbon (DOC), suspended solids (TSS), and other complexing ligands; however, no studies have examined the relative importance of Ni exposure through different compartments (water, sediment, food). Hyalella azteca and Lymnaea stagnalis were exposed to Ni-amended water, sediment, and food, either separately or in combination. Both organisms experienced survival and growth effects in several Ni compartment tests. The DOC amendments attenuated L. stagnalis Ni effects (survival, growth, and (62)Ni bioaccumulation), and presence of TSS exposures demonstrated both protective and synergistic effects on H. azteca and L. stagnalis. (62)Ni trophic transfer from food to H. azteca and L. stagnalis was negligible; however, bioaccumulating (62)Ni was attributed to (62)Ni-water ((62)Ni flux from food), (62)Ni-TSS, and (62)Ni-food. Overall, H. azteca and L. stagnalis Ni compartment toxicity increased in the following order: Ni-water > Ni-sediment > Ni-all (water, sediment, food) > Ni-food. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Environ: E00510 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available E00510 Leech Hirudo Crude drug Hirudin Hirudo nipponia [TAX:42736], Whitmania pigra [TAX...:486152], Whitmania acranulata, Whitmania [TAX:307843] ... Hirudidae Hirudo nipponia, Whitmania pigra, Whitmania acranulata ...

  16. Egg predators of an endemic Italian salamander, Salamandrina perspicillata (Savi, 1821

    Directory of Open Access Journals (Sweden)

    Antonio Romano

    2008-05-01

    Full Text Available We report new aquatic predators feeding on Northern spectacled salamander eggs, Salamandrina perspicillata, an endemic Italian species. Eggs were preyed upon by the leech, Trocheta bykowskii, and the trichopteran larvae of Potamophylax cingulatus and Halesus appenninus.

  17. Politeness Strategies in Good-news Business Letters

    Institute of Scientific and Technical Information of China (English)

    毕争; 李纳

    2008-01-01

    This paper analyzes the presentation of politeness in good-news business letters at the lexical,syntactic,and discourse levels based on Leech's Politeness Principle and Brown and Levinson's Face-saving Theory.

  18. Structural and Dynamic Insight into Hirudin Epitopes-HLA- DRB1 ...

    African Journals Online (AJOL)

    It is produced in the salivary glands of the leech Hirudo .... for epitope selection has a specific algorithm and was developed in ..... from Plasmodium falciparum pre-erythrocytic-stage antigens ... Comar M. Identification of a vaccine against.

  19. Voelt de medicinale bloedzuiger Hirudo medicinalis zich wel zo lekker in Nederland (Hirudinea)?

    OpenAIRE

    Felix, R.P.W.H.; Velde, van der, G.

    2000-01-01

    Does the medicinal leech Hirudo medicinalis feel well in the Netherlands (Hirudinea)? This paper provides information on the medicinal leech Hirudo medicinalis Linnaeus, 1758 particularly in The Netherlands. Although this species was common in The Netherlands in the 18th century, nowadays it is very rare. Most animals were found in waters on sandy soil (71%): dune pools (10%) and pleistocene sandy areas (61%), where it inhabits especially soft water moor and heathland pools. About 20% of the ...

  20. A scientific appraisal on hirudotherapy- an evolution in life style disorders

    Directory of Open Access Journals (Sweden)

    Shikha Nayak

    2015-11-01

    Full Text Available Introduction: Hirudotherapy is a treatment with using of medicinal leech. This kind of therapy is known from the time of extreme antiquity and is still alive nowadays.Aims: At the present era when the world is suffering from a number of disorders occurring due to faulty Life style, Hirudotherapy is an evolutionary mode of treatment. Scientifically it has been proved that Substances in Leech saliva can lower the blood sugar levels and improve pancreatic functions, so can use in diabetes and its complications. Scientific research of Hirudo Medicinalis by number of powerful enzymes extracted from leeches salivary gland secretions among them DESTABILASE which in nature can be found only in leeches. This also explains the Atherogenic Effect provided by the leeches, for they lower the level of Cholesterol and Triglycerides in blood.Conclusion:  As Leech Therapy is being used frequently in a number of disorders, the evidence based concept is the need of the hour. The present paper portrays the scientific substantiation of Hirudotherapy.

  1. Which way is up? Asymmetric spectral input along the dorsal-ventral axis influences postural responses in an amphibious annelid.

    Science.gov (United States)

    Jellies, John

    2014-11-01

    Medicinal leeches are predatory annelids that exhibit countershading and reside in aquatic environments where light levels might be variable. They also leave the water and must contend with terrestrial environments. Yet, leeches generally maintain a dorsal upward position despite lacking statocysts. Leeches respond visually to both green and near-ultraviolet (UV) light. I used LEDs to test the hypothesis that ventral, but not dorsal UV would evoke compensatory movements to orient the body. Untethered leeches were tested using LEDs emitting at red (632 nm), green (513 nm), blue (455 nm) and UV (372 nm). UV light evoked responses in 100 % of trials and the leeches often rotated the ventral surface away from it. Visible light evoked no or modest responses (12-15 % of trials) and no body rotation. Electrophysiological recordings showed that ventral sensilla responded best to UV, dorsal sensilla to green. Additionally, a higher order interneuron that is engaged in a variety of parallel networks responded vigorously to UV presented ventrally, and both the visible and UV responses exhibited pronounced light adaptation. These results strongly support the suggestion that a dorsal light reflex in the leech uses spectral comparisons across the dorsal-ventral axis rather than, or in addition to, luminance.

  2. Neuro-endocrine disruption in molluscs

    DEFF Research Database (Denmark)

    Holbech, Henrik; Bech Sanderhoff, Lene; Waller, Stine P.

    The Mollusca phylum is the second largest animal phylum with around 85,000 registered mollusc species and increasing attention to effects of chemicals on the molluscan endocrine system have been given during the last years. This includes initiation of the development of OECD test guidelines (TG...... efficient and fast in vivo system using embryos of the freshwater pulmonate gastropod Lymnaea stagnalis (the great pond snail). It is known that serotonin and dopamine are involved in many reproductive processes in molluscs Incl. egg maturation and spawning and that pedal ciliary activity causing L....... stagnalis embryos to rotate in the eggs is serotonin/dopamine regulated. We have developed a system to quantify embryo rotation and present results of exposure to serotonin, dopamine and different anti-depressive pharmaceuticals (e.g. selective serotonin reuptake inhibitors, SSRI´s) using the L. stagnalis...

  3. Cutaneous leishmaniasis susceptibility mapping using multi-criteria decision-making techniques, analytic hierarchy process (AHP and analytic network process (ANP

    Directory of Open Access Journals (Sweden)

    SEYED VAHID RAZAVI TERMEH

    2018-02-01

    Full Text Available Background & objective:Cutaneous leech is one of the six major diseases and an example of epidemic diseases in tropical regions. Prevalence and spread of this disease is affected by environmental factors and climatic conditions as well as economic, social and cultural issues. In this research, Analytic Hierarchy Process and network analyzes are used to prepare susceptible cutaneous leeches map. Considering high incidence of cutaneous leech in Khuzestan province, Izeh city was selected as a case study.   Materials & Methods: For this purpose, the number of patients affected by this disease in Izeh was obtained from the Provincial Health Center from 2009 to 2014. Information layers of elevation, rainfall, temperature, humidity, distance from river, distance from rural areas and land use were identified as effective parameter and their maps were prepared in GIS environment. Parameters were compared in pairs by using AHP and ANP and weight of each factors determining their impacts was calculated in Expert Choice and Super Decision software. Then these parameters were combined based on their obtained weights in ArcGIS software and the final cutaneous leech map was prepared. Evaluation of these methods was performed using relative operation curve (ROC and 16 points related to leech disease. Result: The results of weighting effective parameters using AHP and ANP showed that the highest weight is related to elevation, temperature and rainfall parameters, respectively. The results of ROC assessment showed that in preparing the map, ANP had an accuracy of 87.8% and AHP had an accuracy of 68.9%. Conclusion:The results of ANP showed that this model had suitable accuracy in preparing susceptible cutaneous leech map and AHP had moderate accuracy in preparing susceptible cutaneous leech map.

  4. Caracterización de la comunidad bacteriana aerobia en sanguijuelas (Hirudinea, Haementeria sp. (Glossiphoniidae y Oxytychus ornatus (Macrobdellidae de El Bagre, Antioquia = Characterization of the aerobic bacterial community in leeches Haementeria sp (Hirudinea: Glossiphoniidae y Oxytychus ornatus (Hirudinea: Macrobdellidae de El Bagre, Antioquia

    Directory of Open Access Journals (Sweden)

    López Isaza, Laura Patricia

    2012-01-01

    Full Text Available Se ha incrementado el uso terapéutico de las sanguijuelas y se ha demostrado que ellas pueden inocular bacterias causantes de infecciones en el 20% de los pacientes. El hallazgo en Antioquia de dos especies de sanguijuelas promisorias para hirudoterapia motivó este estudio para identificar las bacterias en la superficie, la probóscide y el intestino de estos anélidos y evaluar su sensibilidad a antibióticos. Las sanguijuelas estudiadas se identificaron como Haementeria sp., y Oxytychus ornatus. Muestras de la superficie, boca e intestino de ambos anélidos se inocularon en agar sangre, agar sangre con ampicilina y agar eosina azul de metileno. La identificación de las bacterias y su sensibilidad a antibióticos se evaluaron por el método automatizado Vitek (Biomerieux®. Se hicieron en total 26 aislamientos pertenecientes a 12 especies de nueve géneros. Enterobacter cloacae fue la especie más frecuente en ambos anélidos. Las bacterias fueron sensibles a los antibióticos comúnmente empleados en las infecciones causadas por este tipo de microorganismos. Se sugiere hacer profilaxis con antibióticos en los pacientes que reciban terapia con los anélidos investigados e implementar los protocolos estandarizados para el lavado de los animales antes de su uso y para el aseo de los acuarios en donde se los mantenga.

  5. The fate of received sperm in the reproductive tract of a hermaphroditic snail and its implications for fertilisation.

    NARCIS (Netherlands)

    Koene, J.M.; Montagne-Wajer, K; Roelofs, D.; ter Maat, A.

    2009-01-01

    Multiple mating, sperm storage and internal fertilisation enhance sperm competition. The great pond snail can use stored sperm for over three months, and frequently mates with different partners. This hermaphrodite, Lymnaea stagnalis, can also self-fertilise and often produces egg masses containing

  6. On the identity of Dorylaimus robustus de Man

    NARCIS (Netherlands)

    Loof, P.A.A.

    1961-01-01

    The taxonomic position of Dorylaimus robustus de Man, 1876 is fully discussed. It is concluded that D. robustus de Man, 1876 is a synonym of D. stagnalis Dujardin, 1845; also included in this synonymy are D. robustus apud de Man, 1880, apud de Man, 1884 (male, partim) and Labronema robustum (de Man,

  7. Change of hemoagglutinin and hemolysin titers in hemolymph of gastropod molluscs in response to immunization with sheep erythrocytes

    NARCIS (Netherlands)

    Baskakov, AV; Polevshchikov, AV; Harazova, AD; Krasnodembskii, EG

    2000-01-01

    This work deals with analysis of changes of the levels of hemoagglutinins (HA) and hemolysins (HL) in hemolymph of three gastropod species, Planorbius corneus, Lymnea stagnalis, and Achatina fulica, in response to immunization with sheep erythrocytes (ShE). The levels of HA and HL were determined

  8. Cell type-specific sorting of neuropeptides : a mechanism to modulate peptide composition of large dense core vesicles

    NARCIS (Netherlands)

    Klumperman, J.; Spijker, S.; Minnen, J. van; Sharp-Baker, H.; Smit, A.B.; Geraerts, W.P.M.

    1996-01-01

    The CNS of Lymnaea stagnalis contains two populations of egg-laying hormone (ELH)-producing neurons that differ in size and topology. In type I neurons, all peptides located C-terminally from the cleavage site Arg-Ser-Arg-Arg180-183 are sorted into secretory large dense-core vesicles (LDCV), whereas

  9. Avian Schistosomes and Outbreaks of Cercarial Dermatitis

    Czech Academy of Sciences Publication Activity Database

    Horák, P.; Mikeš, L.; Lichtenbergová, L.; Skála, V.; Soldánová, Miroslava; Brant, S. V.

    2015-01-01

    Roč. 28, č. 1 (2015), s. 165-190 ISSN 0893-8512 Institutional support: RVO:60077344 Keywords : fresh water snails * Lymnae stagnalis hemocytes * Trichobilharzia regenti schistosomatidae Subject RIV: FN - Epidemiology, Contagious Diseases ; Clinical Immunology Impact factor: 16.187, year: 2015

  10. Single-cell analysis of peptide expression and electrophysiology of right parietal neurons involved in male copulation behavior of a simultaneous hermaphrodite

    NARCIS (Netherlands)

    El Filali, Z.; de Boer, P.A.C.M.; Pieneman, A.W.; de Lange, R.P.J.; Jansen, R.F.; Ter Maat, A.; van der Schors, R.C.; Li, K.W.; van Straalen, N.M.; Koene, J.M.

    2015-01-01

    Male copulation is a complex behavior that requires coordinated communication between the nervous system and the peripheral reproductive organs involved in mating. In hermaphroditic animals, such as the freshwater snail Lymnaea stagnalis, this complexity increases since the animal can behave both as

  11. Interference microscopy under double-wavelet analysis: A new approach to studying cell dynamics

    DEFF Research Database (Denmark)

    Sosnovtseva, Olga; Pavlov, A.N.; Brazhe, N.A.

    2005-01-01

    This Letter combines a novel experimental approach to the study of intracellular processes with a newly developed technique for multimode time-series analysis. Experiments are performed on isolated pond snail (Lymnaea stagnalis) neurons. Local variations in the cellular refractive index as detect...

  12. Mercury transfer from fish carcasses to scavengers in boreal lakes: the use of stable isotopes of mercury

    International Nuclear Information System (INIS)

    Sarica, Jose; Amyot, Marc; Hare, Landis; Blanchfield, Paul; Bodaly, R.A.; Hintelmann, Holger; Lucotte, Marc

    2005-01-01

    Scavengers play an important role in the flow of energy, matter and pollutants through food webs. For methylmercury (MeHg), which biomagnifies along food chains, the movement of this metal from fish carcasses to aquatic scavengers has never been demonstrated. We measured the transfer of MeHg from fish carcasses to scavenging leeches in two lakes and in the laboratory. The results of a field experiment indicated that leeches were attracted to fish carcasses and that their Hg concentrations increased by as much as a factor of 5 during the time that Hg-rich fish were available for consumption. Under controlled conditions, we exposed leeches to 202 Hg-labelled fish that had been marked in situ following a whole lake 202 Hg addition. Leeches rapidly accumulated Hg from carcasses, and within two weeks assumed the isotopic signature of the carcasses. Necrophagous invertebrates could therefore return Hg from fish carcasses to other trophic levels in lakes. - Scavengers such as leeches accumulate mercury from fish carcasses which then may return into the food web

  13. Dicty_cDB: Contig-U16208-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available H306-1B3, complete sequ... 42 0.001 8 ( EY487360 ) CBBP15754.fwd CBBP Hirudo medicinalis hermaphrodi... 58 0....27 1 ( EY489283 ) CBBP16951.fwd CBBP Hirudo medicinalis hermaphrodi... 50 0.27 1 ( EY385189 ) CAXA5562.fwd ...ev CAWZ Helobdella robusta Primary Late... 42 0.37 2 ( EY485499 ) CBBP14631.fwd CBBP Hirudo medicinalis herm...zias latipes EST, clone M046--B11_093. 38 0.39 3 ( EY490006 ) CBBP17391.fwd CBBP Hirudo medicinalis hermaphr...odi... 44 0.39 2 ( EY485498 ) CBBP14631.rev CBBP Hirudo medicinalis hermaphrodi... 44 0.39 2 ( EY503416 ) CB

  14. Dicty_cDB: Contig-U04975-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 6227.fwd CAWX Helobdella robusta Primary Ear... 34 3.5 2 ( DY542495 ) HPO-N-S01-0370-LF Hematopoietic cDNA library...0.95 2 ( DT742604 ) EST1176453 Aquilegia cDNA library Aquilegia formo... 36 0.95 2 ( AC178959 ) Strongylocentrotus purpuratu...43 ) EST1164393 Aquilegia cDNA library Aquilegia formo... 48 0.037 2 ( AC115684 ) Dictyostelium discoideum c...36815 ) MM2_2_4_C09 Sugar beet 10-week GH root cDNA Beta ... 50 0.087 1 ( CF886656 ) tric084xc11.b1 T.reesei mycelial culture..., Version... 50 0.087 1 ( CB907997 ) tric084xc11 T.reesei mycelial culture

  15. Dicty_cDB: Contig-U16556-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 379 ) Dictyostelium discoideum cDNA clone:dda53n08, 3' ... 42 0.041 2 ( FK757919 ) av01018a06r1.1 Symbioti... DW145191 ) CLVX10263.b1_M22.ab1 CLV(XYZ) lettuce virosa Lact... 48 0.050 2 ( FK759690 ) av02060a20r1.1 Symbiotic...1597 ) CAXA9355.rev CAXA Helobdella robusta Subtracted L... 44 0.053 3 ( FK724153 ) av02100l05r1.1 Symbiot...ic sea anemone (Anemonia vi... 48 0.054 3 ( CL080652 ) CH216-159D22_RM4.1 CH216 Xen

  16. Mothers Perception of Teething in Children

    African Journals Online (AJOL)

    TNHJOURNALPH

    includes blistering, bleeding, placing leeches on the gum, applying cautery to the back of the head and lancing- a method where lancet was used to cut the gum in other for the teeth to appear.7 1t was thought that failure of the teeth to appear was due to lack of a pathway and that this was the cause of death from teething,.

  17. Avoidance responses of some indigenous and exotic freshwater ...

    African Journals Online (AJOL)

    1990-04-17

    Apr 17, 1990 ... Many glossiphoniid leeches feed on the body fluids of ben- thic invertebrates, primarily ..... responsive forms as well as for the smaller size classes of all the snail species .... of Natal) for his assistance and critical review of the.

  18. Systematic assessment of constipation on plain abdominal radiographs in children

    International Nuclear Information System (INIS)

    Bosch, Maurice van den; Graafmans, Doortje; Nievelstein, Rutger; Beek, Erik

    2006-01-01

    Constipation in childhood is common and its clinical assessment is often difficult. Plain abdominal radiography is simple and used to quantify constipation. Three scoring systems, those of Barr et al., Leech et al. and Blethyn et al., have been developed to quantify fecal loading on the abdominal radiograph. In order to determine which method is the most useful in clinical practice, we assessed the reproducibility of the three scoring systems. Plain abdominal radiographs from 40 clinically constipated children were retrospectively reviewed by two paediatric radiologists on two separate occasions. The radiographs were scored according to three different systems developed by Barr et al., Leech et al., Blethyn et al. Intraobserver variability and interobserver reproducibility were determined for each system. Kappa coefficients were calculated as indicators of inter- and intraobserver agreement for categorical outcome variables. The Leech score showed the highest reproducibility: the intraobserver agreement was high for both observers (κ values of 0.88 and 1.00, respectively, P<0.05). Furthermore, the interobserver agreement was also high: κ 0.91 in the first round and 0.84 in the second. The Leech score proved to be a highly reproducible tool for assessment of childhood constipation and is of value in clinical practice for systematic assessment of constipation on plain abdominal radiographs in children. (orig.)

  19. Lexical Bundle Analysis in Mathematics Classroom Discourse: The Significance of Stance

    Science.gov (United States)

    Herbel-Eisenmann, Beth; Wagner, David; Cortes, Viviana

    2010-01-01

    In this article, we introduce the lexical bundle, defined by corpus linguists as a group of three or more words that frequently recur together, in a single group, in a particular register (Biber, Johansson, Leech, Conrad, & Finegan, 2006; Cortes, "English for Specific Purposes" 23:397-423, 2004). Attention to lexical bundles helps to explore…

  20. Hirudin in the treatment of arterial and venous thrombotic diseases: a new perspective

    NARCIS (Netherlands)

    Büller, H. R.

    1993-01-01

    The first description of the anticoagulant action of a water-soluble, heat-resistant substance derived from the salivary glands of leeches (Hirudo medicinales) dates back to 1884. This substance was later called hirudin in 1904. Almost no research was done with this compound until the 1960's. More

  1. Translational semantics: A discussion of the second edition of ...

    African Journals Online (AJOL)

    Translational semantics: A discussion of the second edition of Geoffrey Leech's Semantics: the Study of Meaning. N Love. Abstract. No abstract. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT · http://dx.doi.org/10.5774/11-0-106 · AJOL African Journals ...

  2. Compare and Contrast Inductive and Deductive Research Approaches

    Science.gov (United States)

    Soiferman, L. Karen

    2010-01-01

    This discussion paper compares and contrasts "inductive" and "deductive" research approaches as described by Trochim (2006) and Plano Clark and Creswell (2007). It also examines the "exploratory" and "confirmatory" approaches by Onwueghuzie and Leech (2005) with respect to the assumption each holds about the nature of knowledge. The paper starts…

  3. (BPH) by down-regulating the expression of PCNA, CyclinD1 and ...

    African Journals Online (AJOL)

    hope&shola

    2012-04-12

    Apr 12, 2012 ... important in treatments of BPH, such as Saw palmetto,. Pygeum africanum and Hypoxis rooperi (Boyle et al.,. 2000; Wilt et al., 2000, 2002) which have long been used to treat BPH successfully. Qianliening capsule (QC) is a traditional Chinese medicine formulation consisting of wine rhubarb, leech,.

  4. Abelova cena v roce 2008 udělena za objevy v teorii neabelovských grup

    Czech Academy of Sciences Publication Activity Database

    Křížek, Michal; Somer, L.

    2008-01-01

    Roč. 53, č. 3 (2008), s. 177-187 ISSN 0032-2423 R&D Projects: GA AV ČR(CZ) IAA100190803; GA MŠk 1P05ME749 Institutional research plan: CEZ:AV0Z10190503 Keywords : sporadic groups * monster * Leech lattice Subject RIV: BA - General Mathematics

  5. Collection of Hirudinea submitted by F.M. Chutter (national institute for water research, Pretoria) and the geographical distribution of Hirudinea in South Africa

    CSIR Research Space (South Africa)

    Sciacchitano, I

    1963-08-01

    Full Text Available The leeches collected from the Vaal Barrage and from the streams and rivers of the Vaal dam Catchment Barrage by F.andM. from Chutter, which I have just studied, constitute a collection of 121 specimens. I sincerely thank Mr F. M. Chutter for having...

  6. Trypanoplasma borreli cysteine proteinase activities support a conservation of function with respect to digestion of host proteins in common carp

    NARCIS (Netherlands)

    Ruszczyk, Aleksandra; Forlenza, Maria; Joerink, Maaike; Ribeiro, Carla M. S.; Jurecka, Patrycja; Wiegertjes, Geert F.

    2008-01-01

    Trypanoplasma borreli is an extracellular parasite that is transmitted by a leech vector and is naturally found in the blood of cyprinid fish. High parasitemia and associated severe anemia together with splenomegaly are typical of infection of common carp, Cyprinus carpio L. Papain-like cysteine

  7. DESCRIPTIONS OF LAST INSTAR LARVAE OF THREE ENNOMINAE (LEPIDOPTERA : GEOMETRIDAE) SPECIES FROM KOREA

    Institute of Scientific and Technical Information of China (English)

    Mei-huaPiao; Chan-youngLee; Zhi-gangFang

    2004-01-01

    Morphological features of mature larvae of Petelia rivulosa (Butler), Exangerona prattiaria (Leech) and Culcula panterinaria (Bremer & Grey) of Ennominae are described and illustrated. All specimens examined are deposited in the Insect Collection of Department of Forest Resources Protection, Kangwon National University, Korea.

  8. Analysis of recombinant proteins by isoelectric focusing in immobilized pH gradients

    NARCIS (Netherlands)

    Bischoff, Rainer; Roecklin, D.; Roitsch, C.

    1992-01-01

    Isoelectric focusing in immobilized pH gradients (IEF-IPG) was used to analyze three different recombinant proteins. Recombinant leech hirudin (65 amino acids, three disulfide bonds) expressed in Saccharomyces cerevisiae as a secreted protein and purified by anion-exchange and reversed-phase

  9. Management of recurrent nasal vestibular furunculosis by jalaukāvacaraṇa and palliative treatment

    Directory of Open Access Journals (Sweden)

    Amol Sudhakar Kadu

    2017-01-01

    Full Text Available Nasal vestibular furunculosis is a common bacterial skin infection among the general population mostly affecting adults and children.It is characterized by acute localized infection of hair follicle in the skin lining of the nasal vestibule caused by Staphylococcus aureus. Immunodeficiency also plays an important role in recurrent skin and soft tissue infections (SSTI including Nasal furunculosis. Though, the lesion is small, it is extremely painful and tender. Treatment is mostly conservative which consists of warm compresses, analgesics to relieve pain, topical and systemic antibiotics directed against staphylococcus. With rapidly increasing resistance to antibacterial agents, management of these bacterial infections is becoming increasingly difficult. In Ayurveda, it can be correlated with Nāsāruṇaśikhā (Nasal furunculosis. Morphologically, it appears like pīḍikā (Furuncle which is characterized by Rāgayuktaśotha (inflammation with reddening. Jalaukāvacaraṇa (Leech therapy is one of the ancient and important parasurgical procedures described in Ayurveda for treatment of various diseases. In this case, a leech has been applied at the affected area. After leech treatment, throbbing pain was reduced in its intensity followed by gradual reduction in swelling and reddening in two days.This case suggests the utility of leech application in Nasal vestibular furunculosis.

  10. Qualitative Analysis Techniques for the Review of the Literature

    Science.gov (United States)

    Onwuegbuzie, Anthony J.; Leech, Nancy L.; Collins, Kathleen M. T.

    2012-01-01

    In this article, we provide a framework for analyzing and interpreting sources that inform a literature review or, as it is more aptly called, a research synthesis. Specifically, using Leech and Onwuegbuzie's (2007, 2008) frameworks, we delineate how the following four major source types inform research syntheses: talk, observations,…

  11. Case report

    African Journals Online (AJOL)

    abp

    16 janv. 2017 ... We report the case of a 70-year-old man with no past medical history presenting with laryngeal dyspnea associated with low abundant paroxysmal hemoptysis. The patient underwent nasofibroscopy showing the presence of a living and mobile organism at the subglottic level evoking a leech. Extraction ...

  12. PATTERNS OF SEVEN AND COMPLICATED MALARIA IN CHILDREN

    African Journals Online (AJOL)

    GB

    2015-10-04

    Oct 4, 2015 ... the cervical os. She was admitted with the diagnosis of hypovolumic shock and severe anemia secondary to postmenopausal vaginal bleeding. After the patient was stabilized with intravenous crystalloids, the leech was removed from the vagina. She was then transfused with two units of whole blood and.

  13. Systematic assessment of constipation on plain abdominal radiographs in children

    Energy Technology Data Exchange (ETDEWEB)

    Bosch, Maurice van den; Graafmans, Doortje [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Nievelstein, Rutger; Beek, Erik [Wilhelmina Children' s Hospital, Department of Paediatric Radiology, Utrecht (Netherlands)

    2006-03-15

    Constipation in childhood is common and its clinical assessment is often difficult. Plain abdominal radiography is simple and used to quantify constipation. Three scoring systems, those of Barr et al., Leech et al. and Blethyn et al., have been developed to quantify fecal loading on the abdominal radiograph. In order to determine which method is the most useful in clinical practice, we assessed the reproducibility of the three scoring systems. Plain abdominal radiographs from 40 clinically constipated children were retrospectively reviewed by two paediatric radiologists on two separate occasions. The radiographs were scored according to three different systems developed by Barr et al., Leech et al., Blethyn et al. Intraobserver variability and interobserver reproducibility were determined for each system. Kappa coefficients were calculated as indicators of inter- and intraobserver agreement for categorical outcome variables. The Leech score showed the highest reproducibility: the intraobserver agreement was high for both observers ({kappa} values of 0.88 and 1.00, respectively, P<0.05). Furthermore, the interobserver agreement was also high: {kappa} 0.91 in the first round and 0.84 in the second. The Leech score proved to be a highly reproducible tool for assessment of childhood constipation and is of value in clinical practice for systematic assessment of constipation on plain abdominal radiographs in children. (orig.)

  14. Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Pacific Southwest). Brown Rockfish, Copper Rockfish, and Black Rockfish

    Science.gov (United States)

    1989-09-01

    years (430 mm). 1977). Adults usually remain in one Females may mature at 5 years area, but may travel more than 600 km (300 mm); all are mature by 11...and Miller is primarily pelagic nekton (smelt, 1982). anchovies) and zooplankton such as salps , mysids, and crab megalops Parasites include leeches

  15. Politeness Principle in Cross-Culture Communication

    Science.gov (United States)

    Huang, Yongliang

    2008-01-01

    As we all know, different people hold different views about politeness. To be polite, Leech thinks you should follow "Politeness Principle" while Levinson suggests paying attention to others' "Face Wants". Sometimes what the Chinese people considered to be polite may not be true according to western culture. In order to…

  16. Three-dimensional visualisation of developmental stages of an apicomplexan fish blood parasite in its invertebrate host

    Directory of Open Access Journals (Sweden)

    Hayes Polly M

    2011-11-01

    Full Text Available Abstract Background Although widely used in medicine, the application of three-dimensional (3D imaging to parasitology appears limited to date. In this study, developmental stages of a marine fish haemogregarine, Haemogregarina curvata (Apicomplexa: Adeleorina, were investigated in their leech vector, Zeylanicobdella arugamensis; this involved 3D visualisation of brightfield and confocal microscopy images of histological sections through infected leech salivary gland cells. Findings 3D assessment demonstrated the morphology of the haemogregarine stages, their spatial layout, and their relationship with enlarged host cells showing reduced cellular content. Haemogregarine meronts, located marginally within leech salivary gland cells, had small tail-like connections to the host cell limiting membrane; this parasite-host cell interface was not visible in two-dimensional (2D light micrographs and no records of a similar connection in apicomplexan development have been traced. Conclusions This is likely the first account of the use of 3D visualisation to study developmental stages of an apicomplexan parasite in its invertebrate vector. Elucidation of the extent of development of the haemogregarine within the leech salivary cells, together with the unusual connections between meronts and the host cell membrane, illustrates the future potential of 3D visualisation in parasite-vector biology.

  17. Isolation and Characterization of Antithrombin Peptides from the ...

    African Journals Online (AJOL)

    Purpose: To isolate and characterize the antithrombin compounds of Malaysian leeches' saliva collection (LSC) for use as anticoagulant proteins and peptides. Method: Reversed phase - high performance liquid chromatography (RP-HPLC) was used to isolate all proteins from LSC. All isolated proteins were tested for ...

  18. Fungsi Bahasa Dalam Syair Bidasari: Kajian Sosiopragmatik

    OpenAIRE

    Fauzi, Mohd

    2015-01-01

    This writing deals with language functions which adops Leech concepts who uses five language functions. By using those concepts, this writing analyzes "Syair Bidasari" Sociopragmatically. The result shows that "Syair Bidasari" contains some language functions, they are informational, expressive, directive, aesthetic, andfatic language functions.

  19. GABA-ergic neurons in the leach central nervous system

    International Nuclear Information System (INIS)

    Cline, H.T.

    1985-01-01

    GABA is a candidate for an inhibitory neurotransmitter in the leech central nervous system because of the well-documented inhibitory action of GABA in other invertebrates. To demonstrate that GABA meets the criteria used to identify a substance as a neurotransmitter, the author examined GABA metabolism and synaptic interactions of inhibitory motor neurons in two leech species, Hirudo medicinalis and Haementeria ghilianii. Segmental ganglia of the leech ventral nerve cord and identified inhibitors have the capacity to synthesize GABA when incubated in the presence of the precursor glutamate. Application of GABA to cell bodies of excitatory motor neurons or muscle fibers innervated by the inhibitors hyperpolarizes the membrane potential of the target cell and activates a chloride ion conductance channel, similar to the inhibitory membrane response following intracellular stimulation of the inhibitor. Bicuculline methiodide (5 x 10 -5 M), GABA receptor antagonist, blocks reversibly the response to applied GABA and the inhibitory synaptic inputs onto the postsynaptic neurons or muscle fibers without interfering with their excitatory inputs. Furthermore, the inhibitors are included among approximately 25 neurons per segmental ganglion that take up GABA by a high affinity uptake system, as revealed by 3 H-GABA-autoradiography. The development of the capacities to synthesize and to take up GABA were examined in leech embryos. The embryos are able to synthesize GABA at early stages of the development of the nervous system, before any neurons have extended neutrites

  20. The persistence ofhepatitis B antigen in the bloodtneal of the ...

    African Journals Online (AJOL)

    Samples from both the midgut and the rectum remained positive for the entire test period, although with decreasing strength. The results are compared with reports on other arthropods which indicate increasing antigen per- sistence with increasing body size. The findings implicate medicinal leeches as mechanical vectors.

  1. Untitled

    African Journals Online (AJOL)

    The techniques and contrast pelvis was taken and, under sterile precautions, a media have evolved over the years. The current Leech-Wilkinson uterine canulla was inserted. techniques of hysterosalpingography have about a About 10-20ml of Urograffin contrast medium was. 75% correlation with laparoscopy for accuracy ...

  2. Trypanoplasma borreli cystein proteinase activities support a conservation of function with respect to digestion of host proteins in common carp

    NARCIS (Netherlands)

    Ruszczyk, A.; Forlenza, M.; Joerink, M.; Ribeiro, C.M.S.; Jurecka, P.M.; Wiegertjes, G.F.

    2008-01-01

    Trypanoplasma borreli is an extracellular parasite that is transmitted by a leech vector and is naturally found in the blood of cyprinid fish. High parasitemia and associated severe anemia together with splenomegaly are typical of infection of common carp, Cyprinus carpio L. Papain-like cysteine

  3. Vaginal Bleeding In 6 Years Old Young Female: Diagnostic Challenge

    African Journals Online (AJOL)

    A 6 year old young girl was referred to Mendefera (Zoba Debub Referral) Hospital with vaginal bleeding of 4 days duration. She had a history of swimming in a river prior to the incident. An aquatic leech bloated with blood detached from the vagina after 100 milliliters of normal saline flushing into the vagina. The patient was ...

  4. Untitled

    African Journals Online (AJOL)

    forests. The leechs are classified in phylum Annelida, genera himinatis and the species that commonly affects man is nilotica (1, 2). They usually affect the oropharynx causing epistaxis, hemoptysis and hematemesis. ... Taboratory Methods and Diagnosis. 8th ed. Vol. II., pp- 1578 -. 1582. 7. Kunin C.M. 1907 A Ten Year ...

  5. A Pragmatic Analysis of Igbo Names in Adichie's Half of A Yellow Sun

    African Journals Online (AJOL)

    Using Leech's (1983) Socio-pragmatics and Pragmalinguistics, this paper shows how Chimamanda Ngozi Adichie uses naming to expand and limit the actions of her characters in Half of a Yellow Sun. The paper also shows how she uses naming in Igbo to create conflict, suspense, and foreshadowing. Based on the ...

  6. Predicting High School Completion Using Student Performance in High School Algebra: A Mixed Methods Research Study

    Science.gov (United States)

    Chiado, Wendy S.

    2012-01-01

    Too many of our nation's youth have failed to complete high school. Determining why so many of our nation's students fail to graduate is a complex, multi-faceted problem and beyond the scope of any one study. The study presented herein utilized a thirteen-step mixed methods model developed by Leech and Onwuegbuzie (2007) to demonstrate within a…

  7. Uptake of uranium by native aquatic plants: potential for bioindication and phytoremediation

    Directory of Open Access Journals (Sweden)

    Favas P. J. C.

    2013-04-01

    Full Text Available The work presented here is a part the on going study on the uraniferous geochemical province of Central Portugal in which, the use of aquatic plants as indicators of uranium contamination is being probed using aquatic plants emphasizing their potential use in the emerging phytotechnologies. Even though we have observed very low concentration of U in the fresh waters of the studied sites we found a set of vegetable species with the ability to accumulate U in concentrations which are orders of magnitude higher than the surrounding environment. We have observed that Apium nodiflorum, Callitriche stagnalis, Lemna minor and Fontinalis antipyretica accumulated significant amounts of uranium, whereas Oenanthe crocata excluded U. These results indicate substantial scope for proper radiophytoremediation and phytosociological investigation exploiting the native flora. These species show great potential for phytoremediation because they are endemic and easy to grow in their native conditions. A. nodiflorum and C. stagnalis have high bioproductivity and yield good biomass.

  8. Species diversity of Plagiorchis Luhe, 1899 (Digenea: Plagiorchiidae) in lymnaeid snails from freshwater ecosystems in central Europe revealed by molecules and morphology

    Czech Academy of Sciences Publication Activity Database

    Zikmundová, Jana; Georgieva, Simona; Faltýnková, Anna; Soldánová, Miroslava; Kostadinova, Aneta

    2014-01-01

    Roč. 88, č. 1 (2014), s. 37-54 ISSN 0165-5752 R&D Projects: GA ČR GAP505/10/1562; GA ČR GBP505/12/G112 Institutional support: RVO:60077344 Keywords : larval trematodes digenea * partial lsrDNA sequences * great pond snail * maximum-likelihood * Lymnea stagnalis * life -cycle * platyhelminthes * differentiation * omphalometridae * phylogenies Subject RIV: EH - Ecology, Behaviour Impact factor: 1.336, year: 2014

  9. Consolidation of long-term memory by insulin in Lymnaea is not brought about by changing the number of insulin receptors

    OpenAIRE

    Hatakeyama, Dai; Okuta, Akiko; Otsuka, Emi; Lukowiak, Ken; Ito, Etsuro

    2013-01-01

    The pond snail Lymnaea stagnalis learns taste aversion and consolidates it into long-term memory (LTM). This is referred to as conditioned taste aversion (CTA). The superfusion of molluscan insulin-related peptides (MIPs) over the isolated snail brain causes a long-term enhancement of synaptic input between the cerebral giant cell and the B1 buccal motor neuron. This enhancement is hypothesized to underlie CTA. The synaptic enhancement caused by the superfusion of MIPs can be blocked by the a...

  10. The polarity protein Par6 is coupled to the microtubule network during molluscan early embryogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Homma, Taihei [Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Shimizu, Miho [Kuroda Chiromorphology Team, ERATO-SORST, JST, Komaba, Meguro-ku, Tokyo 153-8902 (Japan); Kuroda, Reiko, E-mail: ckuroda@mail.ecc.u-tokyo.ac.jp [Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Kuroda Chiromorphology Team, ERATO-SORST, JST, Komaba, Meguro-ku, Tokyo 153-8902 (Japan); Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902 (Japan)

    2011-01-07

    Research highlights: {yields} The cDNAs encoding Par6 and aPKC homologues were cloned from the snail Lymnaea stagnalis. {yields} L. stagnalis Par6 directly interacts with tubulin and microtubules and localizes to the microtubule cytoskeleton during the early embryogenesis. {yields} Identical sequence and localization of LsPar6 for the dextral and the sinistral snails exclude the possibility of the gene being the primary determinant of body handedness. -- Abstract: Cell polarity, which directs the orientation of asymmetric cell division and segregation of fate determinants, is a fundamental feature of development and differentiation. Regulators of polarity have been extensively studied, and the critical importance of the Par (partitioning-defective) complex as the polarity machinery is now recognized in a wide range of eukaryotic systems. The Par polarity module is evolutionarily conserved, but its mechanism and cooperating factors vary among different systems. Here we describe the cloning and characterization of a pond snail Lymnaea stagnalis homologue of partitioning-defective 6 (Lspar6). The protein product LsPar6 shows high affinity for microtubules and localizes to the mitotic apparatus during embryonic cell division. In vitro assays revealed direct binding of LsPar6 to tubulin and microtubules, which is the first evidence of the direct interaction between the two proteins. The interaction is mediated by two distinct regions of LsPar6 both located in the N-terminal half. Atypical PKC, a functional partner of Par6, was also found to localize to the mitotic spindle. These results suggest that the L. stagnalis Par complex employs the microtubule network in cell polarity processes during the early embryogenesis. Identical sequence and localization of LsPar6 for the dextral and the sinistral snails exclude the possibility of the gene being the primary determinant of handedness.

  11. The polarity protein Par6 is coupled to the microtubule network during molluscan early embryogenesis

    International Nuclear Information System (INIS)

    Homma, Taihei; Shimizu, Miho; Kuroda, Reiko

    2011-01-01

    Research highlights: → The cDNAs encoding Par6 and aPKC homologues were cloned from the snail Lymnaea stagnalis. → L. stagnalis Par6 directly interacts with tubulin and microtubules and localizes to the microtubule cytoskeleton during the early embryogenesis. → Identical sequence and localization of LsPar6 for the dextral and the sinistral snails exclude the possibility of the gene being the primary determinant of body handedness. -- Abstract: Cell polarity, which directs the orientation of asymmetric cell division and segregation of fate determinants, is a fundamental feature of development and differentiation. Regulators of polarity have been extensively studied, and the critical importance of the Par (partitioning-defective) complex as the polarity machinery is now recognized in a wide range of eukaryotic systems. The Par polarity module is evolutionarily conserved, but its mechanism and cooperating factors vary among different systems. Here we describe the cloning and characterization of a pond snail Lymnaea stagnalis homologue of partitioning-defective 6 (Lspar6). The protein product LsPar6 shows high affinity for microtubules and localizes to the mitotic apparatus during embryonic cell division. In vitro assays revealed direct binding of LsPar6 to tubulin and microtubules, which is the first evidence of the direct interaction between the two proteins. The interaction is mediated by two distinct regions of LsPar6 both located in the N-terminal half. Atypical PKC, a functional partner of Par6, was also found to localize to the mitotic spindle. These results suggest that the L. stagnalis Par complex employs the microtubule network in cell polarity processes during the early embryogenesis. Identical sequence and localization of LsPar6 for the dextral and the sinistral snails exclude the possibility of the gene being the primary determinant of handedness.

  12. Impairing DNA methylation obstructs memory enhancement for at least 24?hours in Lymnaea

    OpenAIRE

    Rothwell, Cailin M.; Lukowiak, Ken D.

    2017-01-01

    ABSTRACT Stressor-induced memory enhancement has previously been shown to involve DNA methylation in the mollusc Lymnaea stagnalis. Specifically, injection of the DNA methylation inhibitor 5-AZA one hour before exposure to a memory-enhancing stressor obstructs memory augmentation. However, the duration of the influence of 5-AZA on this memory enhancement has not yet been examined. In this study, 2 memory-enhancing stressors (a thermal stress and exposure to the scent of a predator) were used ...

  13. Parasites in a man-made landscape: contrasting patterns of trematode flow in a fishpond area in Central Europe

    Czech Academy of Sciences Publication Activity Database

    Soldánová, Miroslava; Faltýnková, Anna; Scholz, Tomáš; Kostadinova, Aneta

    2011-01-01

    Roč. 138, č. 6 (2011), 789-807 ISSN 0031-1820 R&D Projects: GA ČR GAP505/10/1562; GA ČR GD206/09/H026; GA MŠk LC522 Institutional research plan: CEZ:AV0Z60220518 Keywords : Lymnaea stagnalis * trematode community structure * spatial variation * parasite flow * eutrophic fishponds Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.961, year: 2011

  14. Potentiation of zinc stress caused by parastic infection of snails

    Energy Technology Data Exchange (ETDEWEB)

    Guth, D.J. (Univ. of Michigan, Flint); Blankespoor, H.D.; Cairns, J. Jr.

    1977-09-08

    The purpose of this experiment was to determine the effects of parasitism (Schistosomatium douthitti Price and Trichobilharzia sp.) on the tolerance of snails Lymnaea stagnalis (L.) to acutely lethal concentrations of zinc. Significant reduction in tolerance occurred for snails with patent infections at 24 and 75 ppM of Zn/sup + +/. At two selected prepatent levels of parasite development, significant differences occurred at the higher concentration only.

  15. A homolog of the vertebrate pituitary adenylate cyclase-activating polypeptide is both necessary and instructive for the rapid formation of associative memory in an invertebrate

    OpenAIRE

    Pirger, Zsolt; László, Zita; Kemenes, Ildikó; Tóth, Gábor; Reglődi, Dóra; Kemenes, György

    2010-01-01

    Similar to other invertebrate and vertebrate animals, cAMP dependent signaling cascades are key components of long-term memory (LTM) formation in the snail Lymnaea stagnalis, an established experimental model for studying evolutionarily conserved molecular mechanisms of long-term associative memory. Although a great deal is already known about the signaling cascades activated by cAMP, the molecules involved in the learning-induced activation of adenylate cyclase (AC) in Lymnaea remained unkno...

  16. Aquatic dance flies fauna (Diptera, Empididae: Clinocerinae and Hemerodromiinae) of Montenegro

    OpenAIRE

    Ivković, Marija; Mihaljević, Zlatko; Miliša, Marko; Previšić, Ana

    2013-01-01

    Adult aquatic dance flies (Empididae) were collected during July 2012 and July 2013 in Montenegro using sweep nets and by aspirator at 21 sampling sites. From 25 species recorded in this study, 22 species are new to the fauna of Montenegro: Chelifera pyrenaica Vaillant, Hemerodromia laudatoria Collin, Clinocera stagnalis (Haliday), Clinocera wesmaeli (Macquart), Clinocerella sorex (Engel), Dolichocephala guttata (Haliday), Kowarzia barbatula Mik, Kowarzia plectrum Mik, Roederiodes macedonicus...

  17. Habitat stability, predation risk and ‘memory syndromes’

    OpenAIRE

    S. Dalesman; A. Rendle; S.R.X. Dall

    2015-01-01

    Habitat stability and predation pressure are thought to be major drivers in the evolutionary maintenance of behavioural syndromes, with trait covariance only occurring within specific habitats. However, animals also exhibit behavioural plasticity, often through memory formation. Memory formation across traits may be linked, with covariance in memory traits (memory syndromes) selected under particular environmental conditions. This study tests whether the pond snail, Lymnaea stagnalis, demonst...

  18. Predicting dietborne metal toxicity from metal influxes

    Science.gov (United States)

    Croteau, M.-N.; Luoma, S.N.

    2009-01-01

    Dietborne metal uptake prevails for many species in nature. However, the links between dietary metal exposure and toxicity are not well understood. Sources of uncertainty include the lack of suitable tracers to quantify exposure for metals such as copper, the difficulty to assess dietary processes such as food ingestion rate, and the complexity to link metal bioaccumulation and effects. We characterized dietborne copper, nickel, and cadmium influxes in a freshwater gastropod exposed to diatoms labeled with enriched stable metal isotopes. Metal influxes in Lymnaea stagnalis correlated linearly with dietborne metal concentrations over a range encompassing most environmental exposures. Dietary Cd and Ni uptake rate constants (kuf) were, respectively, 3.3 and 2.3 times higher than that for Cu. Detoxification rate constants (k detox) were similar among metals and appeared 100 times higher than efflux rate constants (ke). Extremely high Cu concentrations reduced feeding rates, causing the relationship between exposure and influx to deviate from linearity; i.e., Cu uptake rates leveled off between 1500 and 1800 nmol g-1 day-1. L. stagnalis rapidly takes up Cu, Cd, and Ni from food but detoxifies the accumulated metals, instead of reducing uptake or intensifying excretion. Above a threshold uptake rate, however, the detoxification capabilities of L. stagnalis are overwhelmed.

  19. Bioaccumulation and toxicity of CuO nanoparticles by a freshwater invertebrate after waterborne and dietborne exposures

    Science.gov (United States)

    Croteau, Marie-Noele; Misra, Superb K.; Luoma, Samuel N.; Valsami-Jones, Eugenia

    2014-01-01

    The incidental ingestion of engineered nanoparticles (NPs) can be an important route of uptake for aquatic organisms. Yet, knowledge of dietary bioavailability and toxicity of NPs is scarce. Here we used isotopically modified copper oxide (65CuO) NPs to characterize the processes governing their bioaccumulation in a freshwater snail after waterborne and dietborne exposures. Lymnaea stagnalis efficiently accumulated 65Cu after aqueous and dietary exposures to 65CuO NPs. Cu assimilation efficiency and feeding rates averaged 83% and 0.61 g g–1 d–1 at low exposure concentrations (–1), and declined by nearly 50% above this concentration. We estimated that 80–90% of the bioaccumulated 65Cu concentration in L. stagnalis originated from the 65CuO NPs, suggesting that dissolution had a negligible influence on Cu uptake from the NPs under our experimental conditions. The physiological loss of 65Cu incorporated into tissues after exposures to 65CuO NPs was rapid over the first days of depuration and not detectable thereafter. As a result, large Cu body concentrations are expected in L. stagnalis after exposure to CuO NPs. To the degree that there is a link between bioaccumulation and toxicity, dietborne exposures to CuO NPs are likely to elicit adverse effects more readily than waterborne exposures.

  20. Biogeochemical controls of uranium bioavailability from the dissolved phase in natural freshwaters

    Science.gov (United States)

    Croteau, Marie-Noele; Fuller, Christopher C.; Cain, Daniel J.; Campbell, Kate M.; Aiken, George R.

    2016-01-01

    To gain insights into the risks associated with uranium (U) mining and processing, we investigated the biogeochemical controls of U bioavailability in the model freshwater speciesLymnaea stagnalis (Gastropoda). Bioavailability of dissolved U(VI) was characterized in controlled laboratory experiments over a range of water hardness, pH, and in the presence of complexing ligands in the form of dissolved natural organic matter (DOM). Results show that dissolved U is bioavailable under all the geochemical conditions tested. Uranium uptake rates follow first order kinetics over a range encompassing most environmental concentrations. Uranium uptake rates in L. stagnalis ultimately demonstrate saturation uptake kinetics when exposure concentrations exceed 100 nM, suggesting uptake via a finite number of carriers or ion channels. The lack of a relationship between U uptake rate constants and Ca uptake rates suggest that U does not exclusively use Ca membrane transporters. In general, U bioavailability decreases with increasing pH, increasing Ca and Mg concentrations, and when DOM is present. Competing ions did not affect U uptake rates. Speciation modeling that includes formation constants for U ternary complexes reveals that the aqueous concentration of dicarbonato U species (UO2(CO3)2–2) best predicts U bioavailability to L. stagnalis, challenging the free-ion activity model postulate.

  1. Strain-specific differences of the effects of stress on memory in Lymnaea.

    Science.gov (United States)

    Hughes, Emily; Shymansky, Tamila; Swinton, Erin; Lukowiak, Kai S; Swinton, Cayley; Sunada, Hiroshi; Protheroe, Amy; Phillips, Iain; Lukowiak, Ken

    2017-03-01

    Stress alters the ability to form, recall and maintain memory according to the Yerkes-Dodson/Hebb (YDH) law. The effects of environmentally relevant stressors, such as low environmental calcium and crowding, on learning and memory have previously been described in a laboratory-reared 'average' strain of Lymnaea stagnalis (i.e. the Dutch strain) as well as two strains of freshly collected L . stagnalis with enhanced memory formation abilities (i.e. 'smart' snails). Here, we use L . stagnalis to study the effects of other environmentally relevant stressors on memory formation in two other strains of freshly collected snails, one 'smart' and one 'average'. The stressors we examined are thermal, resource restriction combined with food odour, predator detection and, for the first time, tissue injury (shell damage). We show that the same stressor has significantly different effects on memory formation depending on whether snails are 'smart' or 'average'. Specifically, our data suggest that a stressor or a combination of stressors act to enhance memory in 'average' snails but obstruct memory formation in 'smart' snails. These results are consistent with the YDH law and our hypothesis that 'smart' snails are more easily stressed than 'average' snails. © 2017. Published by The Company of Biologists Ltd.

  2. The Effect of Exercise Training on Skeletal Muscle Glucose Transorter Isoform GLUT4 Concentration in the Obese Zucker Rat

    Science.gov (United States)

    1991-05-01

    Kinesiology as part of an interdisciplinary program with the Department of Chemistry and Biochemistry . The thesis serves to fulfill the requirements for the...degree of Master of Arts in the Department of Chemistry and Biochemistry . I’d like to thank my fellow graduate students in the Exercise Metabolism...epitrochlearis muscle. Am. J. Physiol. 249:C226-C232, 1985. Newsholme, E.A. & Leech, A.R. Biochemistry for the medical sciences. John Wiley & Sons

  3. Endemic Scrub Typhus-like Illness, Chile

    Science.gov (United States)

    2011-09-01

    We report a case of scrub typhus in a 54-year-old man who was bitten by several terrestrial leeches during a trip to Chiloé Island in southern...vectors for murine typhus (R. typhi) and fl ea-borne spotted fever (R. felis), mites as vectors of rickettsialpox (R. akari), and scrub typhus ...rickettsial disease have been reported in this country since 1976 (3). Scrub typhus , caused by O. tsutsugamushi, which is usually transmitted by

  4. Semantic Analysis of Fast Food Advertisement Slogans

    OpenAIRE

    Ginting, Enda Christiani Nora

    2017-01-01

    The aims of this study are to find out the types of meaning,and explain the ways of fast food advertisement slogans. This research is conducted by using descriptive qualitative design. The data are analyze by using The seven types of meaning is conducted by using Semantics (the study of meaning) theory by G. Leech (1983). The data are divided into Seven Types of meaning,they are; Conceptual meaning, Connotative meaning, Social meaning, Affective meaning, Reflected meaning, C...

  5. Naval Medical Research and Development News. Volume 8, Issue 6

    Science.gov (United States)

    2016-06-01

    infection during pregnancy can cause a serious birth defect called microcephaly and other severe fetal brain defects, the CDC says. In May 2015, the...from parasitic diseases like shistosomiasis to alcoholism well into the twentieth century. Venesection or blood-letting was a common practice...application of leeches to the temples. Narcotics like laudanum ( alcoholic solution containing opium), black drop (opium, vinegar, and sugar

  6. Successful microsurgical lip replantation: Monitoring venous congestion by blood glucose measurements in the replanted lip

    OpenAIRE

    Kazufumi Tachi; Masanori Mori; Reiko Tsukuura; Rintaro Hirai

    2018-01-01

    Replantation of an amputated lip using microvascular anastomosis is the best option for restoration of the defect. However, the amputated region often lacks veins with appropriate diameters for microvascular anastomoses and typically necessitates both postoperative exsanguination using medicinal leeches and a blood transfusion. We present a case of the successful replantation of an avulsed lip in which postoperative congestion was evaluated objectively by measuring blood glucose levels in the...

  7. Simbol-simbol Dalam Upacara Minum Teh (Tea Pay) Pada Pernikahan Etnis Tionghoa Di Manado ( Suatu Analisis Semiotik)

    OpenAIRE

    MOCODOMPIS, LISA OCTAVIN

    2016-01-01

    This research is aimed to identify, classify, and analyze the symbols in Tea Ceremony of Chinese Ethnic Marriage in Manado. The data were collected by getting some information from informants. The identification and classification of the data are based on Peirce theory about semiotics in this case symbol, and the analysis used is descriptive method using Leech's meaning theory. The problems in this research what the verbal and non-verbal symbols are and what the meanings of those symbols in T...

  8. A Case Study on the Mortality of Cobia (Rachycentron canadum) Cultured in Traditional Cages

    OpenAIRE

    Chu, Kua Beng; Abdulah, Azila; Abdullah, Siti Zahrah; Bakar, Ramley Abu

    2013-01-01

    The mass mortality of cobia (Rachycentron canadum) within 2–3 days was reported by 3 private farms in Bukit Tambun, Pulau Pinang, in February and March 2007. Only cobia with body weights of 3–4 kg were affected. Most diseased cobia swam on the surface and displayed flashing behaviour. All samples were positive for viral nervous necrosis (VNN) with low to medium levels of infection. Infestations by leeches (Zeylanicobdella arugamensis), body monogeneans (Benedenia sp.) and copepods (Caligus sp...

  9. Nutrition and Physical Performance in Military Environments

    Science.gov (United States)

    1987-12-01

    as in military field trials. 2.0 Selective macronutrient utiliation and exercise Intensity Newsholme and Leech (5) calculated the duration of time...activities which demand short bursts of explosive power for only a few seconds. With regard to specific macronutrients , the availability of carbohydrates...187 g carbohydrate per day. Further support comes from a study by Saltin (17) on two teams of soccer players, one of which exercised hard to become

  10. Differentially expressed genes in Hirudo medicinalis ganglia after acetyl-L-carnitine treatment.

    Directory of Open Access Journals (Sweden)

    Giuseppe Federighi

    Full Text Available Acetyl-L-carnitine (ALC is a naturally occurring substance that, when administered at supra-physiological concentration, is neuroprotective. It is involved in membrane stabilization and in enhancement of mitochondrial functions. It is a molecule of considerable interest for its clinical application in various neural disorders, including Alzheimer's disease and painful neuropathies. ALC is known to improve the cognitive capability of aged animals chronically treated with the drug and, recently, it has been reported that it impairs forms of non-associative learning in the leech. In the present study the effects of ALC on gene expression have been analyzed in the leech Hirudo medicinalis. The suppression subtractive hybridisation methodology was used for the generation of subtracted cDNA libraries and the subsequent identification of differentially expressed transcripts in the leech nervous system after ALC treatment. The method detects differentially but also little expressed transcripts of genes whose sequence or identity is still unknown. We report that a single administration of ALC is able to modulate positively the expression of genes coding for functions that reveal a lasting effect of ALC on the invertebrate, and confirm the neuroprotective and neuromodulative role of the substance. In addition an important finding is the modulation of genes of vegetal origin. This might be considered an instance of ectosymbiotic mutualism.

  11. Differentially expressed genes in Hirudo medicinalis ganglia after acetyl-L-carnitine treatment.

    Science.gov (United States)

    Federighi, Giuseppe; Macchi, Monica; Bernardi, Rodolfo; Scuri, Rossana; Brunelli, Marcello; Durante, Mauro; Traina, Giovanna

    2013-01-01

    Acetyl-L-carnitine (ALC) is a naturally occurring substance that, when administered at supra-physiological concentration, is neuroprotective. It is involved in membrane stabilization and in enhancement of mitochondrial functions. It is a molecule of considerable interest for its clinical application in various neural disorders, including Alzheimer's disease and painful neuropathies. ALC is known to improve the cognitive capability of aged animals chronically treated with the drug and, recently, it has been reported that it impairs forms of non-associative learning in the leech. In the present study the effects of ALC on gene expression have been analyzed in the leech Hirudo medicinalis. The suppression subtractive hybridisation methodology was used for the generation of subtracted cDNA libraries and the subsequent identification of differentially expressed transcripts in the leech nervous system after ALC treatment. The method detects differentially but also little expressed transcripts of genes whose sequence or identity is still unknown. We report that a single administration of ALC is able to modulate positively the expression of genes coding for functions that reveal a lasting effect of ALC on the invertebrate, and confirm the neuroprotective and neuromodulative role of the substance. In addition an important finding is the modulation of genes of vegetal origin. This might be considered an instance of ectosymbiotic mutualism.

  12. Impact of toxic cyanobacteria on gastropods and microcystin accumulation in a eutrophic lake (Grand-Lieu, France) with special reference to Physa (= Physella) acuta

    International Nuclear Information System (INIS)

    Lance, Emilie; Brient, Luc; Carpentier, Alexandre; Acou, Anthony; Marion, Loic; Bormans, Myriam; Gerard, Claudia

    2010-01-01

    Hepatotoxic microcystins (MCs) produced by cyanobacteria are known to accumulate in gastropods following grazing of toxic cyanobacteria and/or absorption of MCs dissolved in water, with adverse effects on life history traits demonstrated in the laboratory. In the field, such effects may vary depending on species, according to their relative sensitivity and ecology. The aims of this study were to i) establish how various intensities of MC-producing cyanobacteria proliferations alter the structure of gastropod community and ii) compare MC tissue concentration in gastropods in the field with those obtained in our previous laboratory experiments on the prosobranch Potamopyrgus antipodarum and the pulmonate Lymnaea stagnalis. We explored these questions through a one-year field study at three stations at Grand-Lieu Lake (France) affected by different intensities of cyanobacteria proliferations. A survey of the community structure and MC content of both cyanobacteria and gastropods was associated with a caging experiment involving P. antipodarum and L. stagnalis. In total, 2592 gastropods belonging to 7 prosobranch and 16 pulmonate species were collected. However, distribution among the stations was unequal with 62% vs 2% of gastropods sampled respectively at the stations with the lowest vs highest concentrations of MC. Irrespective of the station, pulmonates were always more diverse, more abundant and occurred at higher frequencies than prosobranchs. Only the pulmonate Physa acuta occurred at all stations, with abundance and MC tissue concentration (≤ 4.32 μg g DW -1 ) depending on the degrees of MC-producing cyanobacteria proliferations in the stations; therefore, P. acuta is proposed as a potential sentinel species. The caging experiment demonstrated a higher MC accumulation in L. stagnalis (≤ 0.36 μg g DW -1 for 71% of individuals) than in P. antipodarum (≤ 0.02 μg g DW -1 for 12%), corroborating previous laboratory observations. Results are discussed in

  13. A flavonol present in cocoa [(-)epicatechin] enhances snail memory.

    Science.gov (United States)

    Fruson, Lee; Dalesman, Sarah; Lukowiak, Ken

    2012-10-15

    Dietary consumption of flavonoids (plant phytochemicals) may improve memory and neuro-cognitive performance, though the mechanism is poorly understood. Previous work has assessed cognitive effects in vertebrates; here we assess the suitability of Lymnaea stagnalis as an invertebrate model to elucidate the effects of flavonoids on cognition. (-)Epicatechin (epi) is a flavonoid present in cocoa, green tea and red wine. We studied its effects on basic snail behaviours (aerial respiration and locomotion), long-term memory (LTM) formation and memory extinction of operantly conditioned aerial respiratory behaviour. We found no significant effect of epi exposure (15 mg l(-1)) on either locomotion or aerial respiration. However, when snails were operantly conditioned in epi for a single 0.5 h training session, which typically results in memory lasting ~3 h, they formed LTM lasting at least 24 h. Snails exposed to epi also showed significantly increased resistance to extinction, consistent with the hypothesis that epi induces a more persistent LTM. Thus training in epi facilitates LTM formation and results in a more persistent and stronger memory. Previous work has indicated that memory-enhancing stressors (predator kairomones and KCl) act via sensory input from the osphradium and are dependent on a serotonergic (5-HT) signalling pathway. Here we found that the effects of epi on LTM were independent of osphradial input and 5-HT, demonstrating that an alternative mechanism of memory enhancement exists in L. stagnalis. Our data are consistent with the notion that dietary sources of epi can improve cognitive abilities, and that L. stagnalis is a suitable model with which to elucidate neuronal mechanisms.

  14. [Radioecological studies of freshwater mollusks in the Chernobyl accident exclusion zone].

    Science.gov (United States)

    Gudkov, D I; Nazarov, A B; Dziubenko, E V; Kaglian, A E; Klenus, V G

    2009-01-01

    Species-specificity and dynamics of 90Sr, 137Cs and some transuranic elements accumulation in bivalve and gastropod freshwater molluscs of the Chernobyl exclusion zone during 1997-2008 was analyzed. The results of radiation dose and chromosome aberration rate estimation and the analysis of hemolymph composition of freshwater snail (Lymnaea stagnalis L.) was produced. The absorbed dose rate was registered in the range of 0.3-85.0 microGy/h. In closed water bodies the heightened chromosome aberration rate (up to 27%) in embryo tissues, and also the change of haematological indexes for the adult individuals of snails was registered.

  15. Survival and growth of freshwater pulmonate and nonpulmonate snails in 28-day exposures to copper, ammonia, and pentachlorophenol

    Science.gov (United States)

    Besser, John M.; Dorman, Rebecca A.; Hardesty, Douglas K.; Ingersoll, Christopher G.

    2016-01-01

    We performed toxicity tests with two species of pulmonate snails (Lymnaea stagnalis and Physa gyrina) and four taxa of nonpulmonate snails in the family Hydrobiidae (Pyrgulopsis robusta,Taylorconcha serpenticola, Fluminicola sp., and Fontigens aldrichi). Snails were maintained in static-renewal or recirculating culture systems with adults removed periodically to isolate cohorts of offspring for toxicity testing. This method successfully produced offspring for both species of pulmonate snails and for two hydrobiid species, P. robusta and Fluminicola sp. Toxicity tests were performed for 28 days with copper, ammonia, and pentachlorophenol in hard reconstituted water with endpoints of survival and growth. Tests were started with 1-week-old L. stagnalis, 2-week-old P. gyrina, 5- to 13-week-old P. robusta and Fluminicola sp., and older juveniles and adults of several hydrobiid species. For all three chemicals, chronic toxicity values for pulmonate snails were consistently greater than those for hydrobiid snails, and hydrobiids were among the most sensitive taxa in species sensitivity distributions for all three chemicals. These results suggest that the toxicant sensitivity of nonpulmonate snails in the family Hydrobiidae would not be adequately represented by results of toxicity testing with pulmonate snails.

  16. Pharmacological effects of cannabinoids on learning and memory in Lymnaea.

    Science.gov (United States)

    Sunada, Hiroshi; Watanabe, Takayuki; Hatakeyama, Dai; Lee, Sangmin; Forest, Jeremy; Sakakibara, Manabu; Ito, Etsuro; Lukowiak, Ken

    2017-09-01

    Cannabinoids are hypothesized to play an important role in modulating learning and memory formation. Here, we identified mRNAs expressed in Lymnaea stagnalis central nervous system that encode two G-protein-coupled receptors ( Lymnaea CBr-like 1 and 2) that structurally resemble mammalian cannabinoid receptors (CBrs). We found that injection of a mammalian CBr agonist WIN 55,212-2 (WIN 55) into the snail before operant conditioning obstructed learning and memory formation. This effect of WIN 55 injection persisted for at least 4 days following its injection. A similar obstruction of learning and memory occurred when a severe traumatic stimulus was delivered to L. stagnalis In contrast, injection of a mammalian CBr antagonist AM 251 enhanced long-term memory formation in snails and reduced the duration of the effects of the severe traumatic stressor on learning and memory. Neither WIN 55 nor AM 251 altered normal homeostatic aerial respiratory behaviour elicited in hypoxic conditions. Our results suggest that putative cannabinoid receptors mediate stressful stimuli that alter learning and memory formation in Lymnaea This is also the first demonstration that putative CBrs are present in Lymnaea and play a key role in learning and memory formation. © 2017. Published by The Company of Biologists Ltd.

  17. Silver bioaccumulation dynamics in a freshwater invertebrate after aqueous and dietary exposures to nanosized and ionic Ag

    Science.gov (United States)

    le Croteau, Marie-Noe; Misra, Superb K.; Luoma, Samuel N.; Valsami-Jones, Eugenia

    2011-01-01

    We compared silver (Ag) bioavailability and toxicity to a freshwater gastropod after exposure to ionic silver (Ag+) and to Ag nanoparticles (Ag NPs) capped with citrate or with humic acid. Silver form, exposure route, and capping agent influence Ag bioaccumulation dynamics in Lymnaea stagnalis. Snails efficiently accumulated Ag from all forms after either aqueous or dietary exposure. For both exposure routes, uptake rates were faster for Ag+ than for Ag NPs. Snails efficiently assimilated Ag from Ag NPs mixed with diatoms (assimilation efficiency (AE) ranged from 49 to 58%) and from diatoms pre-exposed to Ag+ (AE of 73%). In the diet, Ag NPs damaged digestion. Snails ate less and inefficiently processed the ingested food, which adversely impacted their growth. Loss rates of Ag were faster after waterborne exposure to Ag NPs than after exposure to dissolved Ag+. Once Ag was taken up from diet, whether from Ag+ or Ag NPs, Ag was lost extremely slowly. Large Ag body concentrations are thus expected in L. stagnalis after dietborne exposures, especially to citrate-capped Ag NPs. Ingestion of Ag associated with particulate materials appears as the most important vector of uptake. Nanosilver exposure from food might trigger important environmental risks.

  18. Energetic endpoints provide early indicators of life history effects in a freshwater gastropod exposed to the fungicide, pyraclostrobin

    International Nuclear Information System (INIS)

    Fidder, Bridgette N.; Reátegui-Zirena, Evelyn G.; Olson, Adric D.; Salice, Christopher J.

    2016-01-01

    Organismal energetics provide important insights into the effects of environmental toxicants. We aimed to determine the effects of pyraclostrobin on Lymnaea stagnalis by examining energy allocation patterns and life history traits. Juvenile snails exposed to pyraclostrobin decreased feeding rate and increased apparent avoidance behaviors at environmentally relevant concentrations. In adults, we found that sublethal concentrations of pyraclostrobin did not affect reproductive output, however, there were significant effects on developmental endpoints with longer time to hatch and decreased hatching success in pyraclostrobin-exposed egg masses. Further, there were apparent differences in developmental effects depending on whether mothers were also exposed to pyraclostrobin suggesting this chemical can exert intergenerational effects. Pyraclostrobin also affected protein and carbohydrate content of eggs in mothers that were exposed to pyraclostrobin. Significant effects on macronutrient content of eggs occurred at lower concentrations than effects on gross endpoints such as hatching success and time to hatch suggesting potential value for these endpoints as early indicators of ecologically relevant stress. These results provide important insight into the effects of a common fungicide on important endpoints for organismal energetics and life history. - Highlights: • We exposed a freshwater snail to relevant concentrations of pyraclostrobin. • We monitored energetic and life history endpoints. • Pyraclostrobin affected feeding, hatching success and egg macronutrient content. • Energetic-based endpoints may provide valuable insight to toxic effects. - The fungicide pyraclostrobin at environmentally relevant concentrations effects a range of life history and energetic endpoints in the freshwater snail, Lymnaea stagnalis.

  19. The numbers game: quantitative analysis of Neorickettsia sp. propagation through complex life cycle of its digenean host using real-time qPCR.

    Science.gov (United States)

    Greiman, Stephen E; Tkach, Vasyl V

    2016-07-01

    Bacteria of the genus Neorickettsia are obligate intracellular endosymbionts of parasitic flukes (Digenea) and are passed through the entire complex life cycle of the parasite by vertical transmission. Several species of Neorickettsia are known to cause diseases in domestic animals, wildlife, and humans. Quantitative data on the transmission of the bacteria through the digenean life cycle is almost completely lacking. This study quantified for the first time the abundance of Neorickettsia within multiple stages of the life cycle of the digenean Plagiorchis elegans. Snails Lymnaea stagnalis collected from a pond in North Dakota were screened for the presence of digenean cercariae, which were subsequently tested for the presence of Neorickettsia. Three L. stagnalis were found shedding P. elegans cercariae infected with Neorickettsia. These snails were used to initiate three separate laboratory life cycles and obtain all life cycle stages for bacterial quantification. A quantitative real-time PCR assay targeting the GroEL gene was developed to enumerate Neorickettsia sp. within different stages of the digenean life cycle. The number of bacteria significantly increased throughout all stages, from eggs to adults. The two largest increases in number of bacteria occurred during the period from eggs to cercariae and from 6-day metacercariae to 48-h juvenile worms. These two periods seem to be the most important for Neorickettsia propagation through the complex digenean life cycle and maturation in the definitive host.

  20. Time-delay-induced phase-transition to synchrony in coupled bursting neurons

    Science.gov (United States)

    Adhikari, Bhim Mani; Prasad, Awadhesh; Dhamala, Mukeshwar

    2011-06-01

    Signal transmission time delays in a network of nonlinear oscillators are known to be responsible for a variety of interesting dynamic behaviors including phase-flip transitions leading to synchrony or out of synchrony. Here, we uncover that phase-flip transitions are general phenomena and can occur in a network of coupled bursting neurons with a variety of coupling types. The transitions are marked by nonlinear changes in both temporal and phase-space characteristics of the coupled system. We demonstrate these phase-transitions with Hindmarsh-Rose and Leech-Heart interneuron models and discuss the implications of these results in understanding collective dynamics of bursting neurons in the brain.

  1. [Dental aspects of general symptoms in the 18th century].

    Science.gov (United States)

    Forrai, Judit

    2009-05-24

    In the 18th century, numerous diseases with symptoms of oral cavity were cured by chirurgien-dentist, barber-surgeons, or tooth drawer. The so called "dentitio difficilis" was blamed for the high children mortality, therefore gum cut or use of leeches was advised as a treatment. Both acute and chronic type of gum inflammation was called scurvy. It seems that the mechanical removal of plaque was enough to cure the scurvy as it was written in advertisements from that time. Syphilis was present in the everyday life throughout centuries, and assumed to cause different stigmas in the oral cavity. Today we consider theses stigmas as the toxic signs of mercury treatment.

  2. Gerel Shakeeva, Traditional Medicine

    OpenAIRE

    Churyumova, Elvira

    2016-01-01

    In her childhood Gerel witnessed in Lagan' how sick people were cured with leeches that were collected from the local lake. In Gerel’s native village there is a hydrogen sulphate spring which is good for mosquito bites. But the spring is poisonous and many children in the village suffered from goiter. Gerel says melted butter was widely used in the treatment of many diseases. People smeared their hair with butter, massaged their ailing joints and drank butter with Kalmyk tea (which is believ...

  3. ACETYL-L-CARNITINE AFFECTS THE ELECTRICAL ACTIVITY OF MECHANOSENSORY NEURONS IN HIRUDO MEDICINALIS GANGLIA

    Directory of Open Access Journals (Sweden)

    Giovanna Traina

    2017-04-01

    Full Text Available Was previously discovered that in the leech Hirudo medicinalis, acetyl-l-carnitine (ALC affects forms of non-associative learning, such as sensitization and dishabituation, due to nociceptive stimulation of the dorsal skin in the swim induction behavioural paradigm, likely through modulating the activity of the mechanosensory tactile (T neurons, which initiate swimming. Since was found that ALC impaired sensitization and dishabituation, both of which are mediated by the neurotransmitter serotonin, the present study analyzed how ALC may interfere with the sensitizing response. Was already found that ALC reduced the activity of nociceptive (N neurons, which modulate T cell activity through serotonergic mediation.

  4. Effect of depletion of interstitial hyaluronan on hydraulic conductance in rabbit knee synovium

    Science.gov (United States)

    Coleman, P J; Scott, D; Abiona, A; Ashhurst, D E; Mason, R M; Levick, J R

    1998-01-01

    The hydraulic resistance of the synovial lining to fluid outflow from a joint cavity () is important for the retention of intra-articular lubricant. The resistance has been attributed in part to extracellular glycosaminoglycans, including hyaluronan and chondroitin sulphates. Increased permeability in joints infused with testicular hyaluronidase, which digests both chondroitin sulphates and hyaluronan, supports this view. In this study the importance of interstitial hyaluronan per se was assessed using leech and Streptomyces hyaluronidases, which degrade only hyaluronan. Ringer solution was infused into the knee joint cavity of anaesthetized rabbits for 30 min, with or without hyaluronidase, after which intra-articular pressure (Pj) was raised and the relation between pressure and outflow determined. Treatment with Streptomyces, leech or testicular hyaluronidases increased the fluid escape rates by similar factors, namely 4- to 6-fold. After Streptomyces hyaluronidase treatment the slope d/dPj, which at low pressures represents synovial hydraulic conductance, increased from a control of 0.90 ± 0.20 μl min−1 cmH2O−1 (mean ± s.e.m., n = 6) to 4.52 ± 0.70 μl min−1 cmH2O−1. The slope d/dPj increased to a similar level after testicular hyaluronidase, namely to 4.14 ± 1.06 μl min−1 cmH2O−1 (control, 0.54 ± 0.24 μl min−1 cmH2O−1). Streptomyces and leech hyaluronidases were as effective as testicular hyaluronidase (no statistically significant differences) despite differences in substrate specificity. It was shown using histochemical and immunohistochemical techniques that hyaluronan was removed from the synovium by leech, Streptomyces and testicular hyaluronidases. The binding of antibodies 2-B-6 and 3-B-3 showed that the core proteins of the chondroitin sulphate proteoglycans remained intact after treatment with hyaluronidases, and the binding of 5-D-4 showed that keratan sulphate was unaffected. An azocasein digestion assay confirmed that the

  5. Characterization of purple and green photosynthetic bacteria isolated from the lagoon of Agatti Atoll (Lakshadweep Sea)

    Digital Repository Service at National Institute of Oceanography (India)

    LokaBharathi, P.A.; Chandramohan, D.

    , H. medicinalis. Lastly, the denticles are distinctly sharper and more acute-tipped than those of P. granulosa. The presence of such a denticular curvature and acute tip obviously adds to the sawing efficiency of the jaws of the land-leeches during... around the denticles. In short, a denticle not only pours saliva but is bathed by it also during microincision. A similar intra-denticular salivary discharge has been reported by Damas2 in H. medicinalis. The author is grateful to Dr V. K. Bajpai for help...

  6. An Analysis Of Non-Literal Meaning Used In Reader Digest Magazines Advertisement

    OpenAIRE

    Simanjuntak, Lenni

    2015-01-01

    The object of this study is the Non-literal meaning found in the Reader’s Digest Magazines Advertisements. The objective of the study is to describe the types of non-literal meaning and to expose the meanings of the non-literal meaning in the Reader’s Digest Magazines Advertisement published on July-August 2012, October 2012 and February 2013. The data were analyzed based on the theoretical concept by Leech (1981) and Palmer (1979) which concerned about types and the meanings of non-literal m...

  7. An Analysis of Non-literal Meaning Used in Reader Digest Magazines

    OpenAIRE

    Simanjuntak, Lenni

    2015-01-01

    The object of this study is the Non-literal meaning found in the Reader’s Digest Magazines Advertisements. The objective of the study is to describe the types of non-literal meaning and to expose the meanings of the non-literal meaning in the Reader’s Digest Magazines Advertisement published on July-August 2012, October 2012 and February 2013. The data were analyzed based on the theoretical concept by Leech (1981) and Palmer (1979) which concerned about types and the meanings of non-literal m...

  8. Estádios evolutivos de tripanossomas de Hipostomus punctatus Valenciennes (Osteichthyes, Loricariidae em infecção natural de Batracobdella gemmata Blanchard (Hirudinea, Glossiphoniidae Evolutive stages of tripanosomes of Hipostomus punctatus Valenciennes (Osteichthyes, Loricariidae in natural infection of Batracobdella gemmata Blanchard (Hirudinea, Glossiphoniidae

    Directory of Open Access Journals (Sweden)

    Marta D'Agosto

    1993-01-01

    Full Text Available Seventeen leeches obtained from armoured catfish (Hypostomus punclatus Valenciennes, 1840 infected with Trypanosoma spp. were examined. It was observed the presence of tripomastigotes, epimastigotes and amastigotes forms as well as dividing forms in the proboscis and in the stomach, different from the ones found in the vertebrate host as regards the morfometric features and developing forms. The examination of the contents of rectum did not show tripanosomes. These facts seem to demonstrate that Batracobdella gemmata (Blanchard, 1900 is an invertebrate host of trypanosomes and the transmission is done by means of inoculation.

  9. Bats, Blood-Feeders and Biodiversity

    DEFF Research Database (Denmark)

    Bohmann, Kristine

    DNA metabarcoding of environmental samples has rapidly become a valuable tool for ecological studies such as biodiversity and diet studies. To reveal the diversity in environmental samples such as soil, water, and faeces, this approach principally employs PCR amplification of environmental DNA...... minimising the occurrence of errors. Centered around metabarcoding dietary studies of bat droppings and leech gut contents, this continuous exploration and refinement is reflected in both the work and structure of this thesis. After a thesis introduction and two chapters on environmental DNA and biodiversity...

  10. Hematophagous insects as vectors for frog trypanosomes.

    Science.gov (United States)

    Ramos, B; Urdaneta-Morales, S

    1977-12-01

    Experimental infections of three hematophagous arthropods (Rhodnius prolixus, Aedes aegypti, and Culex pipiens) with a trypanosome of the Trypanosoma rotatorium complex found in the frogs Hyla crepitans and Leptodactylus insularum revealed that A. aegypti is a good host for the flagellate; the course of development in the intestinal tract of the mosquito is described from 15 minutes to 168 hours. C. pipiens showed only low intestinal infections and R. prolixus did not permit development of the parasite. It is postulated that, in addition to the transmission of T. rotatorium by leeches, batrachophilic mosquitoes may transmit the parasite to frogs of more terrestrial habits by being ingested by these anurans.

  11. Worth its salt?

    Science.gov (United States)

    The idea that all underground salt deposits can serve as storage sites for toxic and nuclear waste does not always hold water—literally. According to Daniel Ronen and Brian Berkowitz of Israel's Weizmann Institute of Science and Yoseph Yechieli of the Geological Survey of Israel, some buried salt layers are in fact highly conductive of liquids, suggesting that wastes buried in their confines could easily leech into groundwater and nearby soil.When drilling three wells into a 10,000-year-old salt layer near the Dead Sea, the researchers found that groundwater had seeped into the layer and had absorbed some of its salt.

  12. Giant Glial Cell: New Insight Through Mechanism-Based Modeling

    DEFF Research Database (Denmark)

    Postnov, D. E.; Ryazanova, L. S.; Brazhe, Nadezda

    2008-01-01

    The paper describes a detailed mechanism-based model of a tripartite synapse consisting of P- and R-neurons together with a giant glial cell in the ganglia of the medical leech (Hirudo medicinalis), which is a useful object for experimental studies in situ. We describe the two main pathways...... of the glial cell activation: (1) via IP3 production and Ca2+ release from the endoplasmic reticulum and (2) via increase of the extracellular potassium concentration, glia depolarization, and opening of voltage-dependent Ca2+ channels. We suggest that the second pathway is the more significant...

  13. First record of a digenean from invasive lionfish, Pterois cf. volitans, (Scorpaeniformes: Scorpaenidae) in the northwestern Atlantic Ocean.

    Science.gov (United States)

    Bullard, S A; Barse, A M; Curran, S S; Morris, J A

    2011-10-01

    Adults of Lecithochirium floridense (Digenea: Hemiuridae) parasitized the stomach in each of 22 necropsied lionfish, Pterois cf. volitans (Scorpaeniformes: Scorpaenidae) (prevalence  =  100%, mean intensity  =  11), captured in the northwestern Atlantic Ocean off Beaufort, North Carolina (34°14.83'N, 76°35.25'W). This is the first report of a digenean from the invasive lionfish and that of L. floridense from a species of Pterois. The leech specimen previously identified as Myzobdella lugubris from P. volitans in the northwestern Atlantic Ocean is re-identified as Trachelobdella lubrica based on a study of the original voucher specimen.

  14. Deviation in “Vis and Rāmin” by Fakhruddin As'ad Gurgani

    Directory of Open Access Journals (Sweden)

    Masoud Forouzandeh

    2016-09-01

     Finally, from among all the norm deviations proposed by Leech, temporal, style, written, lexical and, particularly, semantic norm deviations are the ones that can be considered norm deviations to compose poems. It should be said that there were no evidence to indicate the existence of written and style norm deviations in Vis and Ramin. Totally, by analyzing the verses order of occurrence of norm deviations in Vis and Ramin is as follow: syntactic, phonetic, semantic, lexical, temporal and dialectic norm deviations. It is worth mentioning that the poet has observed the elements of conductivity and aesthetic in applying norm deviations.

  15. [Recurrent herpes zoster with neuralgia].

    Science.gov (United States)

    Schwickert, Myriam; Saha, Joyonto

    2006-06-01

    We present the case of a 40-year-old female patient suffering from recurrent herpes zoster and postherpetic neuralgia. Herpes zoster has recurred several times per year for more than 15 years. At admission, rash localised on the right sacral region and accompanied by neuralgia had lasted for 3 months. Standard out-patient treatment remained unsuccessful. A multimodal integrative therapy regimen including fasting, hydrotherapy, leech application and treatment with autologous blood led to rapid healing of herpetic lesions and persistent pain relief. The case is discussed.

  16. Interactions between freshwater snails and tadpoles: competition and facilitation.

    Science.gov (United States)

    Brönmark, Christer; Rundle, Simon D; Erlandsson, Ann

    1991-06-01

    Freshwater snails and anuran tadpoles have been suggested to have their highest population densities in ponds of intermediate size where abiotic disturbance (e.g. desiccation) is low and large predators absent. Both snails and tadpoles feed on periphytic algae and, thus, there should be a large potential for competitive interactions to occur between these two distantly related taxa. In a field experiment we examined the relative strength of competition between two closely related snail species, Lymnaea stagnalis and L. peregra, and between L. stagnalis and tadpoles of the common frog, Rana temporaria. Snail growth and egg production and tadpole size at and time to metamorphosis were determined. Effects on the common food source, periphyton, were monitored with the aid of artificial substrates. Periphyton dry weight was dramatically reduced in the presence of snails and/or tadpoles. There were no competitive effects on growth or egg production of the two snail species when they were coexisting. Mortality of L. peregra was high (95%) after reproduction, but independent of treatment. Growth of L. stagnalis was reduced only at the highest tadpole densities, whereas egg production was reduced both by intraspecific competition and by competition with tadpoles. Differences in egg production were retained after tadpole metamorphosis. Tadpole larval period increased, weight of metamorphosing frogs decreased and growth rate was reduced as a function of increasing tadpole density. However, contrary to expectation, snails had a positive effect on tadpole larval period, weight and growth rate. Further, in experimental containers without snails there was a dense growth of the filamentous green alga Cladophora sp. We suggest that the facilitative effects of snails on tadpoles are due to an "indirect mutualistic" mechanism, involving competition between food sources of different quality (microalgae and Cladophora sp.) and tadpoles being competitively dominant over snails for the

  17. Successful microsurgical lip replantation: Monitoring venous congestion by blood glucose measurements in the replanted lip

    Directory of Open Access Journals (Sweden)

    Kazufumi Tachi

    2018-03-01

    Full Text Available Replantation of an amputated lip using microvascular anastomosis is the best option for restoration of the defect. However, the amputated region often lacks veins with appropriate diameters for microvascular anastomoses and typically necessitates both postoperative exsanguination using medicinal leeches and a blood transfusion. We present a case of the successful replantation of an avulsed lip in which postoperative congestion was evaluated objectively by measuring blood glucose levels in the replanted region. The patient presented to our hospital with an upper lip avulsion that was caused by a dog bite. The lip was replanted by the microvascular anastomoses of one artery and two veins using interposed vein grafts. The replanted lip showed signs of congestion on postoperative day one; exsanguination using medicinal leeches was attempted, while blood glucose levels were measured every three hours. Critical congestion, which did not occur in this patient, was defined as a blood glucose level lower than 40 mg/dL. Lip replantation was successful without any complications in this patient.

  18. THE EFFECT OF IRANIAN FEMALE EFL LEARNERS’ POLITENESS STRATEGIES AWARENESS ON THEIR LETTER WRITING ABILITY

    Directory of Open Access Journals (Sweden)

    Faezeh Yousefian Dastmalchi

    2014-12-01

    Full Text Available This research examines the effect of teaching politeness strategies based on the models proposed by Brown and Levinson (1987 and Leech (1983 to intermediate English learners on their ability in writing more polite letters. The instrumentation includes an IELTS test, used as a placement test, an inventory, used to measure learners’ awareness of politeness strategies, and a letter-writing test, used as a measurement of learners’ ability in using politeness strategies. Among all the participants, twenty of them were put in the control group, and twenty-four of them in the experimental group, who went under the treatment. They were taught how to write politely based on the politeness strategy models proposed by Brown and Levinson (1987 and Leech (1983. After the treatment, learners wrote letters to the same people with the same situations. Comparing the twenty learners in the control group with the twenty-four learners in experimental group, the researchers concluded that the treatment had a significant effect on the learners’ ability in writing more polite letters. They selected to use more formal strategies with those who they saw further distance with, and more informal strategies with more intimate people. Furthermore, the answers the learners provided to the questions of the inventory offered more awareness of politeness strategies. This implies that they were more aware of various choices of polite language that were available for them to use in the given situations.

  19. Therapeutic Response for Functional Abdominal Pain in Children with Occult Constipation: Laxatives versus Prokinetic Drugs.

    Science.gov (United States)

    Ha, Eun Kyo; Jang, Homin; Jeong, Su Jin

    2017-01-01

    The relationship between functional abdominal pain (FAP) and occult constipation (OC) in children who did not meet the Rome III criteria for constipation has rarely been reported. This study aimed to estimate the prevalence of OC in patients with FAP and to compare the effectiveness of prokinetic drugs and laxatives for FAP and OC. Pediatric outpatients (n = 212; aged 4-15 years) who satisfied the Rome III criteria for childhood FAP were divided into 2 groups based on Leech scores: group 1 pain severity was assessed after 2 weeks, 1 month, and 3 months. A total 52.4% (111/212) of patients had OC in this study. More patients who received laxatives had reduced pain scores compared with those who received prokinetic drugs. Those treated with laxatives in group 2 had a better response than those treated with prokinetic drugs throughout the study period (P < 0.001, P < 0.001, and P = 0.002 after 2 weeks, 1 month, and 3 months, respectively). OC was frequently encountered in children with FAP. Laxatives can be more effective than prokinetic drugs for relieving symptoms of FAP in children with a Leech score ≥ 8 and suspected OC.

  20. The use of radiation-induced graft polymerization for obtaining polymeric biomaterial on the basis of preparation 'Piyavit'

    International Nuclear Information System (INIS)

    Kudryavtsev, V.N.; Degtyareva, T.V.; Kabanov, V.Ya.

    1998-01-01

    The purpose of the present study is to obtain hemocompatible polymeric materials. The method of modification of polymer surface have been elaborated using the radiation-induced graft polymerization after which the surface is capable of coupling with the biologically active substances (BAS) produced from the medicinal leeches. At the Biological Department of Lomonosov Moscow State University was created a medicinal preparation 'Piyavit' isolated from the salivary glands secretion of the medicinal leeches (Hirudo medicinalis). It possess a wide spectrum of biological action on the human organism thanks to the presence of an unique complex natural of BAS (enzymes, inhibitors of proteolityc ensymes, prostanoids and et. al) guaranteed the anticoagulating, thrombolytic, antithrombotic, antiphlogistic, antiatherosclerotic, hypotentic effects and et al.. It has several advantages over anticoagulant heparin which is widely used for above mentioned purpose. 'Piyavit' is the multifunctional preparation, has not negative side-effects and is more cheap. The method of obtaining biocompatible polymers (basically polyethylene) with immobilized 'Piyavit' consist of three stages: 1. The modification of polymer surface by the radiation-induced graft polymerization of acrylic acid to obtain grafted chains polyacrylic acid (PAA) with controlled number and length. 2. The treatment of radiation grafted PAA by thionyl chloride that lead to conversion carboxyl groups of PAA in highly reactive acide chloride groups. 3. The covalent immobilization BAS of 'Piyavit' by acylation amino- and hydroxy-groups (functional groups in BAS) by acide chloride of PAA grafted on the polymere. (author)

  1. Development and validation of OECD test guidelines on mollusc reproductive toxicity tests

    DEFF Research Database (Denmark)

    Lagadic, Laurent; Holbech, Henrik; hutchinson, tom

    the comparison of endpoints relevant for reproduction in invertebrates often shows a much higher sensitivity in molluscs vs. e.g. daphnids. The OECD test guideline programme has thus been extended to cover reproduction effects of chemicals in molluscs. Existing mollusc toxicity test protocols have been reviewed...... in an OECD Detailed Review Paper that identifies two relevant candidate species for developing freshwater tests: Potamopyrgus antipodarum and Lymnaea stagnalis. However, this review did not clarify which toxicity test design/conditions are the most appropriate for chemicals assessment. Therefore, a mollusc...... reproduction test guideline will be developed describing partial- and full- life-cycle test protocols in these species, so as to propose a balanced suite of apical mollusc toxicity tests applicable for the assessment of any type of chemical, including endocrine disruptors, as level 4 and 5 assays of the EDTA...

  2. Memory block: a consequence of conflict resolution.

    Science.gov (United States)

    Ito, Etsuro; Yamagishi, Miki; Hatakeyama, Dai; Watanabe, Takayuki; Fujito, Yutaka; Dyakonova, Varvara; Lukowiak, Ken

    2015-06-01

    Food deprivation for 1 day in the pond snail Lymnaea stagnalis before aversive classical conditioning results in optimal conditioned taste aversion (CTA) and long-term memory (LTM) formation, whereas 5-day food deprivation before training does not. We hypothesize that snails do in fact learn and form LTM when trained after prolonged food deprivation, but that severe food deprivation blocks their ability to express memory. We trained 5-day food-deprived snails under various conditions, and found that memory was indeed formed but is overpowered by severe food deprivation. Moreover, CTA-LTM was context dependent and was observed only when the snails were in a context similar to that in which the training occurred. © 2015. Published by The Company of Biologists Ltd.

  3. The Yerkes-Dodson law and appropriate stimuli for conditioned taste aversion in Lymnaea.

    Science.gov (United States)

    Ito, Etsuro; Yamagishi, Miki; Takigami, Satoshi; Sakakibara, Manabu; Fujito, Yutaka; Lukowiak, Ken

    2015-02-01

    The pond snail Lymnaea stagnalis can learn conditioned taste aversion and then consolidate it into long-term memory (LTM). A high-voltage electric shock was used as the unconditioned stimulus, where we have previously used KCl. We varied the strength of both the conditioned and unconditioned stimuli to determine whether the so-called Yerkes-Dodson law prevailed. This is an empirical relationship between the state of arousal and LTM formation, showing that there is an optimal level of arousal leading to memory formation. However, too little or too much arousal results in poorer LTM. We found here that the most appropriate stimuli to use in taste aversion training in Lymnaea were a 10 mmol l(-1) sucrose solution as the conditioned stimulus and a 3 s electric shock as the unconditioned stimulus. © 2015. Published by The Company of Biologists Ltd.

  4. Structural and functional studies of the modulator NS9283 reveal agonist-like mechanism of action at α4β2 nicotinic acetylcholine receptors

    DEFF Research Database (Denmark)

    Olsen, Jeppe A; Ahring, Philip K; Kastrup, Jette Sandholm Jensen

    2014-01-01

    Modulation of Cys loop receptor ion channels is a proven drug discovery strategy, but many underlying mechanisms of the mode of action are poorly understood. We report the x-ray structure of the acetylcholine-binding protein from Lymnaea stagnalis with NS9283, a stoichiometry selective positive...... on efficacy. The shared modulatory profile along with a binding site located in an extracellular subunit interface suggest that modulation via an agonist-like mechanism may be a common mechanism of action that potentially could apply to Cys loop receptors beyond the α4β2 nAChRs....... modulator that targets the α4-α4 interface of α4β2 nicotinic acetylcholine receptors (nAChRs). Together with homology modeling, mutational data, quantum mechanical calculations, and pharmacological studies on α4β2 nAChRs, the structure reveals a modulator binding mode that overlaps the α4-α4 interface...

  5. Mollusc reproductive toxicity tests - Development and validation of test guidelines

    DEFF Research Database (Denmark)

    Ducrot, Virginie; Holbech, Henrik; Kinnberg, Karin Lund

    . Draft standard operating procedures (SOPs) have been designed based upon literature and expert knowledge from project partners. Pre-validation studies have been implemented to validate the proposed test conditions and identify issues in performing the SOPs and analyzing test results. Pre-validation work......The Organisation for Economic Cooperation and Development is promoting the development and validation of mollusc toxicity tests within its test guidelines programme, eventually aiming for the standardization of mollusc apical toxicity tests. Through collaborative work between academia, industry...... and stakeholders, this study aims to develop innovative partial life-cycle tests on the reproduction of the freshwater gastropods Potamopyrgus antipodarum and Lymnaea stagnalis, which are relevant candidate species for the standardization of mollusc apical toxicity tests assessing reprotoxic effects of chemicals...

  6. Reproduction-associated immunoreactive peptides in the nervous systems of prosobranch gastropods.

    Science.gov (United States)

    Ram, J L; Gallardo, C S; Ram, M L; Croll, R P

    1998-12-01

    Antibodies against reproductive peptides of Aplysia and Lymnaea were used to localize homologous immunoreactive peptides in the nervous systems of three prosobranch species: Busycon canaliculatum, Concholepas concholepas, and Tegula atra. Positive control experiments in L. stagnalis demonstrated the broad species range of the anti-egg-laying hormone (anti-ELH) antibody used in this study, and showed binding of anti-alpha-caudodorsal-cell peptide (anti-alpha-CDCP) to the same cells in cerebral and buccal ganglia. Dot immunoassays with synthetic ELH confirmed the reactivity and sensitivity (concholepas and T atra, ELH-like immunoreactivity was found in cerebral ganglia, and in T. atra in fibers in the cerebral ganglia and cerebral-pedal connectives. Thus, cerebral ganglia are the major locus of the ELH-like immunoreactivity in prosobranchs.

  7. Canadian Association of Neurosciences Review: learning at a snail's pace.

    Science.gov (United States)

    Parvez, Kashif; Rosenegger, David; Martens, Kara; Orr, Michael; Lukowiak, Ken

    2006-11-01

    While learning and memory are related, they are distinct processes each with different forms of expression and underlying molecular mechanisms. An invertebrate model system, Lymnaea stagnalis, is used to study memory formation of a non-declarative memory. We have done so because: (1) We have discovered the neural circuit that mediates an interesting and tractable behaviour; (2) This behaviour can be operantly conditioned and intermediate-term and long-term memory can be demonstrated; and (3) It is possible to demonstrate that a single neuron in the model system is a necessary site of memory formation. This article reviews how Lymnaea has been used in the study of behavioural and molecular mechanisms underlying consolidation, reconsolidation, extinction and forgetting.

  8. Annelid Distal-less/Dlx duplications reveal varied post-duplication fates

    Directory of Open Access Journals (Sweden)

    Korchagina Natalia

    2011-08-01

    Full Text Available Abstract Background Dlx (Distal-less genes have various developmental roles and are widespread throughout the animal kingdom, usually occurring as single copy genes in non-chordates and as multiple copies in most chordate genomes. While the genomic arrangement and function of these genes is well known in vertebrates and arthropods, information about Dlx genes in other organisms is scarce. We investigate the presence of Dlx genes in several annelid species and examine Dlx gene expression in the polychaete Pomatoceros lamarckii. Results Two Dlx genes are present in P. lamarckii, Capitella teleta and Helobdella robusta. The C. teleta Dlx genes are closely linked in an inverted tail-to-tail orientation, reminiscent of the arrangement of vertebrate Dlx pairs, and gene conversion appears to have had a role in their evolution. The H. robusta Dlx genes, however, are not on the same genomic scaffold and display divergent sequences, while, if the P. lamarckii genes are linked in a tail-to-tail orientation they are a minimum of 41 kilobases apart and show no sign of gene conversion. No expression in P. lamarckii appendage development has been observed, which conflicts with the supposed conserved role of these genes in animal appendage development. These Dlx duplications do not appear to be annelid-wide, as the polychaete Platynereis dumerilii likely possesses only one Dlx gene. Conclusions On the basis of the currently accepted annelid phylogeny, we hypothesise that one Dlx duplication occurred in the annelid lineage after the divergence of P. dumerilii from the other lineages and these duplicates then had varied evolutionary fates in different species. We also propose that the ancestral role of Dlx genes is not related to appendage development.

  9. Influence of hardness on the bioavailability of silver to a freshwater snail after waterborne exposure to silver nitrate and silver nanoparticles

    Science.gov (United States)

    Stoiber, Tasha L.; Croteau, Marie-Noele; Romer, Isabella; Tejamaya, Mila; Lead, Jamie R.; Luoma, Samuel N.

    2015-01-01

    The release of Ag nanoparticles (AgNPs) into the aquatic environment is likely, but the influence of water chemistry on their impacts and fate remains unclear. Here, we characterize the bioavailability of Ag from AgNO3 and from AgNPs capped with polyvinylpyrrolidone (PVP AgNP) and thiolated polyethylene glycol (PEG AgNP) in the freshwater snail, Lymnaea stagnalis, after short waterborne exposures. Results showed that water hardness, AgNP capping agents, and metal speciation affected the uptake rate of Ag from AgNPs. Comparison of the results from organisms of similar weight showed that water hardness affected the uptake of Ag from AgNPs, but not that from AgNO3. Transformation (dissolution and aggregation) of the AgNPs was also influenced by water hardness and the capping agent. Bioavailability of Ag from AgNPs was, in turn, correlated to these physical changes. Water hardness increased the aggregation of AgNPs, especially for PEG AgNPs, reducing the bioavailability of Ag from PEG AgNPs to a greater degree than from PVP AgNPs. Higher dissolved Ag concentrations were measured for the PVP AgNPs (15%) compared to PEG AgNPs (3%) in moderately hard water, enhancing Ag bioavailability of the former. Multiple drivers of bioavailability yielded differences in Ag influx between very hard and deionized water where the uptake rate constants (kuw, l g-1 d-1 ± SE) varied from 3.1 ± 0.7 to 0.2 ± 0.01 for PEG AgNPs and from 2.3 ± 0.02 to 1.3 ± 0.01 for PVP AgNPs. Modeling bioavailability of Ag from NPs revealed that Ag influx into L. stagnalis comprised uptake from the NPs themselves and from newly dissolved Ag.

  10. Transmission rates of the bacterial endosymbiont, Neorickettsia risticii, during the asexual reproduction phase of its digenean host, Plagiorchis elegans, within naturally infected lymnaeid snails.

    Science.gov (United States)

    Greiman, Stephen E; Tkach, Vasyl V; Vaughan, Jefferson A

    2013-10-22

    Neorickettsia are obligate intracellular bacterial endosymbionts of digenean parasites present in all lifestages of digeneans. Quantitative information on the transmission of neorickettsial endosymbionts throughout the complex life cycles of digeneans is lacking. This study quantified the transmission of Neorickettsia during the asexual reproductive phase of a digenean parasite, Plagiorchis elegans, developing within naturally parasitized lymnaeid pond snails. Lymnaea stagnalis snails were collected from 3 ponds in Nelson County, North Dakota and screened for the presence of digenean cercariae. Cercariae were identified to species by PCR and sequencing of the 28S rRNA gene. Neorickettsia infections were initially detected using nested PCR and sequencing of a partial 16S rRNA gene of pooled cercariae shed from each parasitized snail. Fifty to 100 single cercariae or sporocysts were isolated from each of six parasitized snails and tested for the presence of Neorickettsia using nested PCR to estimate the efficiency at which Neorickettsia were transmitted to cercariae during asexual development of the digenean. A total of 616 L. stagnalis were collected and 240 (39%) shed digenean cercariae. Of these, 18 (8%) were Neorickettsia-positive. Six Neorickettsia infections were selected to determine the transmission efficiency of Neorickettsia from mother to daughter sporocyst and from daughter sporocyst to cercaria. The prevalence of neorickettsiae in cercariae varied from 11 to 91%. The prevalence of neorickettsiae in sporocysts from one snail was 100%. Prevalence of Neorickettsia infection in cercariae of Plagiorchis elegans was variable and never reached 100%. Reasons for this are speculative, however, the low prevalence of Neorickettsia observed in some of our samples (11 to 52%) differs from the high prevalence of other, related bacterial endosymbionts, e.g. Wolbachia in Wolbachia-dependent filariid nematodes, where the prevalence among progeny is universally 100

  11. High dietary quality of non-toxic cyanobacteria for a benthic grazer and its implications for the control of cyanobacterial biofilms.

    Science.gov (United States)

    Groendahl, Sophie; Fink, Patrick

    2017-05-18

    Mass occurrences of cyanobacteria frequently cause detrimental effects to the functioning of aquatic ecosystems. Consequently, attempts haven been made to control cyanobacterial blooms through naturally co-occurring herbivores. Control of cyanobacteria through herbivores often appears to be constrained by their low dietary quality, rather than by the possession of toxins, as also non-toxic cyanobacteria are hardly consumed by many herbivores. It was thus hypothesized that the consumption of non-toxic cyanobacteria may be improved when complemented with other high quality prey. We conducted a laboratory experiment in which we fed the herbivorous freshwater gastropod Lymnaea stagnalis single non-toxic cyanobacterial and unialgal diets or a mixed diet to test if diet-mixing may enable these herbivores to control non-toxic cyanobacterial mass abundances. The treatments where L. stagnalis were fed non-toxic cyanobacteria and a mixed diet provided a significantly higher shell and soft-body growth rate than the average of all single algal, but not the non-toxic cyanobacterial diets. However, the increase in growth provided by the non-toxic cyanobacteria diets could not be related to typical determinants of dietary quality such as toxicity, nutrient stoichiometry or essential fatty acid content. These results strongly contradict previous research which describes non-toxic cyanobacteria as a low quality food resource for freshwater herbivores in general. Our findings thus have strong implications to gastropod-cyanobacteria relationships and suggest that freshwater gastropods may be able to control mass occurrences of benthic non-toxic cyanobacteria, frequently observed in eutrophied water bodies worldwide.

  12. Previous motor activity affects the transition from uncertainty to decision making in snails.

    Science.gov (United States)

    Korshunova, Tatiana A; Vorontsov, Dmitry D; Dyakonova, Varvara E

    2016-11-15

    One of the most widely accepted benefits of enhanced physical activity is an improvement in the symptoms of depression, including the facilitation of decision making. Up until now, these effects have been shown in rodents and humans only. Little is known about their evolutionary origin or biological basis, and the underlying cellular mechanisms also remain relatively elusive. Here, we demonstrate for the first time that preceding motor activity accelerates decision making in an invertebrate, the pond snail Lymnaea stagnalis To investigate decision making in a novel environment, snails, which normally live in water, were placed on a flat dry surface to simulate the potentially threatening consequence of being in an arid environment. This stimulus initiated two distinct phases in snail behaviour: slow circular movements, followed by intense locomotion in a chosen direction. The first phase was prolonged when the test arena was symmetrically lit, compared with one with an apparent gradient of light. However, forced muscular locomotion for 2 h prior to the test promoted the transition from random circular motions to a directional crawl, accompanied by an increase in crawling speed but with no effect on the choice of direction. Intense locomotion for 2 h also produced a strong excitatory effect on the activity of serotonergic neurons in L. stagnalis Our results suggest that the beneficial effects of physical exercise on cognitive performance in mammals might have deep roots in evolution, granting the opportunity to unravel the origins of such effects at the single-neuron and network levels. © 2016. Published by The Company of Biologists Ltd.

  13. Isotopically modified silver nanoparticles to assess nanosilver bioavailability and toxicity at environmentally relevant exposures

    Science.gov (United States)

    Croteau, Marie-Noële; Dybowska, Agnieszka D.; Luoma, Samuel N.; Misra, Superb K.; Valsami-Jones, Eugenia

    2014-01-01

    A major challenge in understanding the environmental implications of nanotechnology lies in studying nanoparticle uptake in organisms at environmentally realistic exposure concentrations. Typically, high exposure concentrations are needed to trigger measurable effects and to detect accumulation above background. But application of tracer techniques can overcome these limitations. Here we synthesised, for the first time, citrate-coated Ag nanoparticles using Ag that was 99.7 % 109Ag. In addition to conducting reactivity and dissolution studies, we assessed the bioavailability and toxicity of these isotopically modified Ag nanoparticles (109Ag NPs) to a freshwater snail under conditions typical of nature. We showed that accumulation of 109Ag from 109Ag NPs is detectable in the tissues of Lymnaea stagnalis after 24-h exposure to aqueous concentrations as low as 6 ng L–1 as well as after 3 h of dietary exposure to concentrations as low as 0.07 μg g–1. Silver uptake from unlabelled Ag NPs would not have been detected under similar exposure conditions. Uptake rates of 109Ag from 109Ag NPs mixed with food or dispersed in water were largely linear over a wide range of concentrations. Particle dissolution was most important at low waterborne concentrations. We estimated that 70 % of the bioaccumulated 109Ag concentration in L. stagnalis at exposures –1 originated from the newly solubilised Ag. Above this concentration, we predicted that 80 % of the bioaccumulated 109Ag concentration originated from the 109Ag NPs. It was not clear if agglomeration had a major influence on uptake rates.

  14. Feedback Signal from Motoneurons Influences a Rhythmic Pattern Generator.

    Science.gov (United States)

    Rotstein, Horacio G; Schneider, Elisa; Szczupak, Lidia

    2017-09-20

    Motoneurons are not mere output units of neuronal circuits that control motor behavior but participate in pattern generation. Research on the circuit that controls the crawling motor behavior in leeches indicated that motoneurons participate as modulators of this rhythmic motor pattern. Crawling results from successive bouts of elongation and contraction of the whole leech body. In the isolated segmental ganglia, dopamine can induce a rhythmic antiphasic activity of the motoneurons that control contraction (DE-3 motoneurons) and elongation (CV motoneurons). The study was performed in isolated ganglia where manipulation of the activity of specific motoneurons was performed in the course of fictive crawling ( crawling ). In this study, the membrane potential of CV was manipulated while crawling was monitored through the rhythmic activity of DE-3. Matching behavioral observations that show that elongation dominates the rhythmic pattern, the electrophysiological activity of CV motoneurons dominates the cycle. Brief excitation of CV motoneurons during crawling episodes resets the rhythmic activity of DE-3, indicating that CV feeds back to the rhythmic pattern generator. CV hyperpolarization accelerated the rhythm to an extent that depended on the magnitude of the cycle period, suggesting that CV exerted a positive feedback on the unit(s) of the pattern generator that controls the elongation phase. A simple computational model was implemented to test the consequences of such feedback. The simulations indicate that the duty cycle of CV depended on the strength of the positive feedback between CV and the pattern generator circuit. SIGNIFICANCE STATEMENT Rhythmic movements of animals are controlled by neuronal networks that have been conceived as hierarchical structures. At the basis of this hierarchy, we find the motoneurons, few neurons at the top control global aspects of the behavior (e.g., onset, duration); and within these two ends, specific neuronal circuits control

  15. Fingertip replantation without venous anastomosis.

    Science.gov (United States)

    Chen, Yi-Chieh; Chan, Fuan Chiang; Hsu, Chung-Chen; Lin, Yu-Te; Chen, Chien-Tzung; Lin, Chih-Hung

    2013-03-01

    Replantation of amputated fingertips is a technical challenge, as many salvage procedures fail because no suitable vein in the fingertip is available for anastomosis. In this study, we examined our experience in fingertip replantation in cases without venous anastomosis with our established fingertip replantation treatment protocol. Between August 2002 and August 2010, a retrospective study examined all patients who had undergone fingertip replantation at Chang-Gung Memorial Hospital. All the patients (n = 24) suffered from complete digital amputations at or distal to the interphalangeal joint of the thumb, or distal to distal interphalangeal joint of the fingers. A total of 30 fingertips that were salvaged by microsurgical anastomosis of the digital arteries but not of digital veins were included in this study. On satisfactory arterial anastomosis, a 2-mm incision was made over the fingertip with a number 11 Scalpel blade, and 0.1 to 0.2 mL heparin (5000 IU/mL) was injected subcutaneously around the incision immediately and once per day thereafter to ensure continuous blood drainage from the replanted fingertip. None of the replanted nail plate was removed, and no medical leeches were used. The perfusion of the replanted digits and patient's hemoglobin level were closely monitored. The wound bleeding was maintained until physiologic venous outflow was restored. Of 30 fingertips, 27 (90%) replanted fingertips survived. The average length needed for maintaining external bleeding by chemical leech was 6.8 days (range, 5-10 days). Twelve patients (including a 2-year-old child) received blood transfusions. The average amount of blood transfusion in the 23 adults was 4.0 units (range, 0-16 units) for each patient or 3.29 units (range, 0-14 units) for each digit. A 2-year-old child received 100 mL blood transfusion or 50 mL for each digit. This study showed that a protocol that promotes controlled bleeding from the fingertip is essential to achieve consistent high

  16. Spikes matter for phase-locked bursting in inhibitory neurons

    Science.gov (United States)

    Jalil, Sajiya; Belykh, Igor; Shilnikov, Andrey

    2012-03-01

    We show that inhibitory networks composed of two endogenously bursting neurons can robustly display several coexistent phase-locked states in addition to stable antiphase and in-phase bursting. This work complements and enhances our recent result [Jalil, Belykh, and Shilnikov, Phys. Rev. EPLEEE81539-375510.1103/PhysRevE.81.045201 81, 045201(R) (2010)] that fast reciprocal inhibition can synchronize bursting neurons due to spike interactions. We reveal the role of spikes in generating multiple phase-locked states and demonstrate that this multistability is generic by analyzing diverse models of bursting networks with various fast inhibitory synapses; the individual cell models include the reduced leech heart interneuron, the Sherman model for pancreatic beta cells, and the Purkinje neuron model.

  17. TINDAK TUTUR SANTUN DALAM KISAH NABI YUSUF

    Directory of Open Access Journals (Sweden)

    Oka Putra Pratama

    2017-12-01

    Full Text Available This study aimed to describe the form of speech acts used in the Surah Yûsuf. When having a dialogue Yûsuf adjusts what form of speech acts will be used for the intended purpose to the interlocutor, and in accordance with the situation and circumstances when the speech occurs. What Yûsuf intends when speaking is different from his formal form of speech. First, the formal form of declarative aimed to request, clarify, convince, inform, warn, defend, and be grateful. Second, the formal form is imperative but can serve to honor, reject, recognition, defense, command. Third, its formal form is interrogative but can serve to resist and ask. Additionally, the Surah Yûsuf obeys Grice’s maxims of principles of cooperation and Leech's politeness scale: maxim quality, maxim of quantity, maxim of appreciation, maxim of relevance, maxim of sympathy, maxim of wisdom, maxim of simplicity (humble, maxim of consent, and maxim of generousity.

  18. Blood meal analysis of tabanid fly after it biting the rare Sumatran rhinoceros.

    Science.gov (United States)

    Rovie-Ryan, Jeffrine Japning; Zainuddin, Zainal Zahari; Marni, Wahap; Ahmad, Abdul Hamid; Ambu, Laurentius N; Payne, Junaidi

    2013-02-01

    To demonstrate a noninvasive large mammalian genetic sampling method using blood meal obtained from a tabanid fly. Blood meal was recovered from the abdomen of an engorged tabanid fly (Haematopota sp.) which was captured immediately after biting a Sumatran rhino in captivity. The blood was applied on to a Whatman FTA(®) blood card. Subsequent laboratory work was conducted to extract, amplify and sequence the DNA from the sample. Validation was done by sampling the hair follicles and blood samples from the rhinoceros and subjecting it to the same laboratory process. BLAST search and constructed phylogenetic trees confirmed the blood meal samples were indeed from the rhino. This method could be used in the field application to noninvasively collect genetic samples. Collection of tabanids and other haematophagous arthropods (e.g. mosquitoes and ticks) and other blood-sucking parasites (e.g. leeches and worms) could also provide information on vector-borne diseases.

  19. Introduction to Sporadic Groups

    Directory of Open Access Journals (Sweden)

    Luis J. Boya

    2011-01-01

    Full Text Available This is an introduction to finite simple groups, in particular sporadic groups, intended for physicists. After a short review of group theory, we enumerate the 1+1+16=18 families of finite simple groups, as an introduction to the sporadic groups. These are described next, in three levels of increasing complexity, plus the six isolated ''pariah'' groups. The (old five Mathieu groups make up the first, smallest order level. The seven groups related to the Leech lattice, including the three Conway groups, constitute the second level. The third and highest level contains the Monster group M, plus seven other related groups. Next a brief mention is made of the remaining six pariah groups, thus completing the 5+7+8+6=26 sporadic groups. The review ends up with a brief discussion of a few of physical applications of finite groups in physics, including a couple of recent examples which use sporadic groups.

  20. Pragmatic Failures in Cross-Cultural Communication

    Institute of Scientific and Technical Information of China (English)

    吴西

    2015-01-01

    Pragmatics was only invented in 1973 and its first major theory,Speech Act Theory,did not take shape until the 50s.G.Leech argues that"we cannot really understand the nature of language itself unless we understand pragmatics:how language is used in communication."Therefore,the most important element in pragmatics is the context.According to Thomas,pragmatic failure can be divided into two levels:pragmalinguistic failure and socio-pragmatic failure.Therefore,communicative competence must include pragmalinguistic competence and sociopragmatic competence,if inter-cultural pragmatic problems are to be avoided.The paper aims to analyze the causes of pragmatic failures and solutions to this problem will be presented.

  1. Pragmatic Failures in Cross-Cultural Communication

    Institute of Scientific and Technical Information of China (English)

    吴西

    2015-01-01

    Pragmatics was only invented in 1973 and its first major theory,Speech Act Theory,did not take shape until the 50s. G.Leech argues that“we cannot really understand the nature of language itself unless we understand pragmatics:how language is used in communication.” Therefore,the most important element in pragmatics is the context.According to Thomas,pragmatic failure can be divided into two levels:pragmalinguistic failure and socio-pragmatic failure.Therefore,communicative competence must include pragmalinguistic competence and sociopragmatic competence,if inter-cultural pragmatic problems are to be avoided.The paper aims to analyze the causes of pragmatic failures and solutions to this problem will be presented.

  2. Requirement for tyrosine phosphatase during serotonergic neuromodulation by protein kinase C.

    Science.gov (United States)

    Catarsi, S; Drapeau, P

    1997-08-01

    Tyrosine kinases and phosphatases are abundant in the nervous system, where they signal cellular differentiation, mediate the responses to growth factors, and direct neurite outgrowth during development. Tyrosine phosphorylation can also alter ion channel activity, but its physiological significance remains unclear. In an identified leech mechanosensory neuron, the ubiquitous neuromodulator serotonin increases the activity of a cation channel by activating protein kinase C (PKC), resulting in membrane depolarization and modulation of the receptive field properties. We observed that the effects on isolated neurons and channels were blocked by inhibiting tyrosine phosphatases. Serotonergic stimulation of PKC thus activates a tyrosine phosphatase activity associated with the channels, which reverses their constitutive inhibition by tyrosine phosphorylation, representing a novel form of neuromodulation.

  3. POLITENESS MAXIM OF MAIN CHARACTER IN SECRET FORGIVEN

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    Sang Ayu Isnu Maharani

    2017-06-01

    Full Text Available Maxim of Politeness is an interesting subject to be discussed, since politeness has been criticized from our childhood. We are obliques to be polite to anyone either in speaking or in acting. Somehow we are manage to show politeness in our spoken expression though our intention might be not so polite. For example we must appriciate others opinion although we feel objection toward the opinion. In this article the analysis of politeness is based on maxim proposes by Leech. He proposed six types of politeness maxim. The discussion shows that the main character (Kristen and Kami use all types of maxim in their conversation. The most commonly used are approbation maxim and agreement maxim

  4. Long term changes in atmospheric N and S throughfall deposition and effects on soil solution chemistry in a Scots pine forest in the Netherlands.

    Science.gov (United States)

    Boxman, Andries W; Peters, Roy C J H; Roelofs, Jan G M

    2008-12-01

    In a Scots pine forest the throughfall deposition and the chemical composition of the soil solution was monitored since 1984. (Inter)national legislation measures led to a reduction of the deposition of nitrogen and sulphur. The deposition of sulphur has decreased by approximately 65%. The total mineral-nitrogen deposition has decreased by ca. 25%, which is mainly due to a reduction in ammonium-N deposition (-40%), since nitrate-N deposition has increased (+50%). The nitrogen concentration in the upper mineral soil solution at 10 cm depth has decreased, leading to an improved nutritional balance, which may result in improved tree vitality. In the drainage water at 90 cm depth the fluxes of NO3(-) and SO4(2-) have decreased, resulting in a reduced leeching of accompanying base cations, thus preserving nutrients in the ecosystem. It may take still several years, however, before this will meet the prerequisite of a sustainable ecosystem.

  5. Stylistic Analysis of the Short Story ‘The Last Word’ by Dr. A. R. Tabassum

    Directory of Open Access Journals (Sweden)

    Abdul Bari Khan

    2015-06-01

    Full Text Available In this article stylistic analysis of short story ‘The Last Word’ by Dr. A. R. Tabassum is performed.  The formative elements of the story, such as point of view, characters and allegorical element, are discussed in detail so as to give a better insight of the story. The story is analyzed stylistically in terms of figures of speech where grammatical, lexical and phonological schemes are considered, following the checklist of linguistic and stylistic categories proposed by Leech and Short. Features of repetition, parallelism, alliteration, consonance, assonance and rhyme are focused on. Finally, the findings and conclusion is given to sum up the discussion. Keywords: stylistics, analysis, short story, last word, allegory, Tabassum

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

    Energy Technology Data Exchange (ETDEWEB)

    Friedrich, G.; Thome, K.N.

    1976-01-01

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

  7. Determination of recombinant hirudin structural deviants by capillary zone electrophoresis augmented with buffer additives.

    Science.gov (United States)

    Dönges, Reiner; Brazel, Dieter

    2002-12-06

    The polypeptide hirudin is a potent and specific thrombin inhibitor used in anticoagulant therapy and naturally occurring in medicinal leech. Using gene-technology methods, recombinant (r) hirudin can be produced on a large scale. Purity evaluation of the synthesized r-hirudin is essential to monitor co-expressed structural deviants and degradation products before therapeutic use. Although the well established RP-HPLC analysis appears to be the method of choice, in the case of r-hirudin baseline separation of the structural deviants is not necessarily achieved. Capillary zone electrophoresis augmented with buffer additives was used as a complementary technique to separate r-hirudin successfully from several similar species, in order to provide characterization information, as well as performing purity control and stability studies.

  8. KAJIAN PERILAKU PRAGMATIS TERHADAP TINDAK TUTUR SANTRI TERHADAP KYAI DI PONDOK PESANTREN DI WILAYAH KOTA SEMARANG

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    Riris Tiani

    2016-12-01

    Full Text Available The main study is speech of moslem students assessed by using pragmatics approach that is politenes principle. Indicator in every maxim of politenes principle is used as santri having (sermon in front of others santri. The goal of the research is to describe about the implementation of politenes principle maxims and to determine the politenes of santri’s speech delivering their sermon to others santri. The result of data analysis found the applications of tive maxims in Leech politenes principle on santri’s speech of the sermon. Its also found the determinant factor of politenes namely linguistics factors and nonlinguistics factors. Linguistics factors was found diction application and style of santri’s speech. Meanwhile, nonlinguistics factors was found that senior santri’s were more in applicating politenes maxim rather than junior santri’s. In addition, the use foreign language such as Arabic.

  9. Identifying crucial parameter correlations maintaining bursting activity.

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    Anca Doloc-Mihu

    2014-06-01

    Full Text Available Recent experimental and computational studies suggest that linearly correlated sets of parameters (intrinsic and synaptic properties of neurons allow central pattern-generating networks to produce and maintain their rhythmic activity regardless of changing internal and external conditions. To determine the role of correlated conductances in the robust maintenance of functional bursting activity, we used our existing database of half-center oscillator (HCO model instances of the leech heartbeat CPG. From the database, we identified functional activity groups of burster (isolated neuron and half-center oscillator model instances and realistic subgroups of each that showed burst characteristics (principally period and spike frequency similar to the animal. To find linear correlations among the conductance parameters maintaining functional leech bursting activity, we applied Principal Component Analysis (PCA to each of these four groups. PCA identified a set of three maximal conductances (leak current, [Formula: see text]Leak; a persistent K current, [Formula: see text]K2; and of a persistent Na+ current, [Formula: see text]P that correlate linearly for the two groups of burster instances but not for the HCO groups. Visualizations of HCO instances in a reduced space suggested that there might be non-linear relationships between these parameters for these instances. Experimental studies have shown that period is a key attribute influenced by modulatory inputs and temperature variations in heart interneurons. Thus, we explored the sensitivity of period to changes in maximal conductances of [Formula: see text]Leak, [Formula: see text]K2, and [Formula: see text]P, and we found that for our realistic bursters the effect of these parameters on period could not be assessed because when varied individually bursting activity was not maintained.

  10. Variation in motor output and motor performance in a centrally generated motor pattern

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    Norris, Brian J.; Doloc-Mihu, Anca; Calabrese, Ronald L.

    2014-01-01

    Central pattern generators (CPGs) produce motor patterns that ultimately drive motor outputs. We studied how functional motor performance is achieved, specifically, whether the variation seen in motor patterns is reflected in motor performance and whether fictive motor patterns differ from those in vivo. We used the leech heartbeat system in which a bilaterally symmetrical CPG coordinates segmental heart motor neurons and two segmented heart tubes into two mutually exclusive coordination modes: rear-to-front peristaltic on one side and nearly synchronous on the other, with regular side-to-side switches. We assessed individual variability of the motor pattern and the beat pattern in vivo. To quantify the beat pattern we imaged intact adults. To quantify the phase relations between motor neurons and heart constrictions we recorded extracellularly from two heart motor neurons and movement from the corresponding heart segments in minimally dissected leeches. Variation in the motor pattern was reflected in motor performance only in the peristaltic mode, where larger intersegmental phase differences in the motor neurons resulted in larger phase differences between heart constrictions. Fictive motor patterns differed from those in vivo only in the synchronous mode, where intersegmental phase differences in vivo had a larger front-to-rear bias and were more constrained. Additionally, load-influenced constriction timing might explain the amplification of the phase differences between heart segments in the peristaltic mode and the higher variability in motor output due to body shape assumed in this soft-bodied animal. The motor pattern determines the beat pattern, peristaltic or synchronous, but heart mechanics influence the phase relations achieved. PMID:24717348

  11. Bringing up the rear: new premotor interneurons add regional complexity to a segmentally distributed motor pattern

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    Norris, Brian J.; Doloc-Mihu, Anca; Calabrese, Ronald L.

    2011-01-01

    Central pattern generators (CPGs) pace and pattern many rhythmic activities. We have uncovered a new module in the heartbeat CPG of leeches that creates a regional difference in this segmentally distributed motor pattern. The core CPG consists of seven identified pairs and one unidentified pair of heart interneurons of which 5 pairs are premotor and inhibit 16 pairs of heart motor neurons. The heartbeat CPG produces a side-to-side asymmetric pattern of activity of the premotor heart interneurons corresponding to an asymmetric fictive motor pattern and an asymmetric constriction pattern of the hearts with regular switches between the two sides. The premotor pattern progresses from rear to front on one side and nearly synchronously on the other; the motor pattern shows corresponding intersegmental coordination, but only from segment 15 forward. In the rearmost segments the fictive motor pattern and the constriction pattern progress from front to rear on both sides and converge in phase. Modeling studies suggested that the known inhibitory inputs to the rearmost heart motor neurons were insufficient to account for this activity. We therefore reexamined the constriction pattern of intact leeches. We also identified electrophysiologically two additional pairs of heart interneurons in the rear. These new heart interneurons make inhibitory connections with the rear heart motor neurons, are coordinated with the core heartbeat CPG, and are dye-coupled to their contralateral homologs. Their strong inhibitory connections with the rearmost heart motor neurons and the small side-to-side phase difference of their bursting contribute to the different motor and beating pattern observed in the animal's rear. PMID:21775711

  12. Pediatric abdominal radiograph use, constipation, and significant misdiagnoses.

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    Freedman, Stephen B; Thull-Freedman, Jennifer; Manson, David; Rowe, Margot Follett; Rumantir, Maggie; Eltorki, Mohamed; Schuh, Suzanne

    2014-01-01

    To determine the proportion of children diagnosed with constipation assigned a significant alternative diagnosis within 7 days (misdiagnosis), if there is an association between abdominal radiograph (AXR) performance and misdiagnosis, and features that might identify children with misdiagnoses. We conducted a retrospective cohort study of consecutive children constipation were eligible. Misdiagnosis was defined as an alternative diagnosis during the subsequent 7 days that resulted in hospitalization or an outpatient procedure that included a surgical or radiologic intervention. Constipation severity was classified employing text word categorization and the Leech score. 3685 eligible visits were identified. Mean age was 6.6 ± 4.4 years. AXR was performed in 46% (1693/3685). Twenty misdiagnoses (0.5%; 95% CI 0.4, 0.8) were identified (appendicitis [7%], intussusception [2%, bowel obstruction [2%], other [9%]). AXR was performed more frequently in misdiagnosed children (75% vs 46%; P = .01). These children more often had abdominal pain (70% vs 49%; P = .04) and tenderness (60% vs 32%; P =.01). Children in both groups had similar amounts of stool on AXR (P = .38) and mean Leech scores (misdiagnosed = 7.9 ± 3.4; not misdiagnosed = 7.7 ± 2.9; P = .85). Misdiagnoses in children with constipation are more frequent in those in whom an AXR was performed and those with abdominal pain and tenderness. The performance of an AXR may indicate diagnostic uncertainty; in such cases, the presence of stool on AXR does not rule out an alternative diagnosis. Copyright © 2014 Mosby, Inc. All rights reserved.

  13. The life history of Hepatozoon leptodactyli (Lesage, 1908 Pessoa, 1970: a parasite of the common laboratory animal: the frog of the genus Leptodactylus

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    Sylvio Celso Goncalves da Costa

    1973-01-01

    Full Text Available The main object of the present paper is to furnish a brief account to the knowledgement of Protozoa parasitic in common Brazilian frog of the genus Leptodactylus for general students in Zoology and for investigators that use this frog as a laboratory animal. Hepatozoon leptodactyli (Haemogregarina leptodactyli was found in two species of frogs - Leptodactylus ocellatus and L. pentadactylus - in which develop schizogony whereas sporogony occurs in the leech Haementeria lutzi as was obtainded in experimental conditions. Intracellular forms have been found in peripheral circulation, chiefly in erythrocytes, but we have found them in leukocytes too. Tissue stages were found in frog, liver, lungs, spleen, gut, brain and heart. The occurence of hemogregarine in the Central Nervous System was recorded by Costa & al,(13 and Ball (2. Some cytochemical methods were employed in attempt to differentiate gametocytes from trophozoites in the peripheral blood and to characterize the cystic membrane as well. The speorogonic cycle was developed in only one specie of leech. A brief description of the parasite is given.Os autores apresentam uma revisão da hemogregarina parasita de rãs do gênero Leptodactylus. A posisção sistemática sob o ponto de vista genérico fica definida com os estudos do ciclo no vetor Haementeria lutzi, publicados em nota preliminar por um dos autores (Pessoa 24 quando utilizou rãs L. petadactylus em trabalho experimental. Este trabalho experimental continua sendo desenvolvido no Laboratório de Protozoologia do Instituto Oswaldo Cruz, utilizando a rã L. ocellatus e as sanguessugas Haementeria vizuttoi e Haementeria gracilis. Algumas técnicas citoquímicas foram empregadas para melhor caracterização dos esquizontes e das granulações do citoplasma das formas sanguíneas.

  14. Haemoprotozoa: Making biological sense of molecular phylogenies

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    Peter O'Donoghue

    2017-12-01

    Full Text Available A range of protistan parasites occur in the blood of vertebrates and are transmitted by haematophagous invertebrate vectors. Some 48 genera are recognized in bood primarily on the basis of parasite morphology and host specificity; including extracellular kinetoplastids (trypanosomatids and intracellular apicomplexa (haemogregarines, haemococcidia, haemosporidia and piroplasms. Gene sequences are available for a growing number of species and molecular phylogenies often link parasite and host or vector evolution. This review endeavours to reconcile molecular clades with biological characters. Four major trypanosomatid clades have been associated with site of development in the vector: salivarian or stercorarian for Trypanosoma, and supra- or peri-pylorian for Leishmania. Four haemogregarine clades have been associated with acarine vectors (Hepatozoon A and B, Karyolysus, Hemolivia and another two with leeches (Dactylosoma, Haemogregarina sensu stricto. Two haemococcidian clades (Lankesterella, Schellackia using leeches and mosquitoes (as paratenic hosts! were paraphyletic with monoxenous enteric coccidia. Two major haemosporidian clades have been associated with mosquito vectors (Plasmodium from mammals, Plasmodium from birds and lizards, two with midges (Hepatocystis from bats, Parahaemoproteus from birds and two with louse-flies and black-flies (Haemoproteus and Leucocytozoon from birds. Three major piroplasm clades were recognized: one associated with transovarian transmission in ticks (Babesia sensu stricto; one with pre-erythrocytic schizogony in vertebrates (Theileria/Cytauxzoon; and one with neither (Babesia sensu lato. Broad comparative studies with allied groups suggest that trypanosomatids and haemogregarines evolved first in aquatic and then terrestrial environments, as evidenced by extant lineages in invertebrates and their radiation in vertebrates. In contrast, haemosporidia and haemococcidia are thought to have evolved first in

  15. Helminthes and insects: maladies or therapies.

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    El-Tantawy, Nora L

    2015-02-01

    By definition, parasites cause harm to their hosts. But, considerable evidence from ancient traditional medicine has supported the theory of using parasites and their products in treating many diseases. Maggots have been used successfully to treat chronic, long-standing, infected wounds which failed to respond to conventional treatment by many beneficial effects on the wound including debridement, disinfection, and healing enhancement. Maggots are also applied in forensic medicine to estimate time between the death and discovery of a corpse and in entomotoxicology involving the potential use of insects as alternative samples for detecting drugs and toxins in death investigations. Leeches are segmented invertebrates, famous by their blood-feeding habits and used in phlebotomy to treat various ailments since ancient times. Leech therapy is experiencing resurgence nowadays in health care principally in plastic and reconstructive surgery. Earthworms provide a source of medicinally useful products with potential antimicrobial, antiviral, and anticancer properties. Lumbrokinases are a group of fibrinolytic enzymes isolated and purified from earthworms capable of degrading plasminogen-rich and plasminogen-free fibrin and so can be used to treat various conditions associated with thrombotic diseases. Helminth infection has been proved to have therapeutic effects in both animal and human clinical trials with promising evidence in treating many allergic diseases and can block the induction of or reduce the severity of some autoimmune disorders as Crohn's disease or ulcerative colitis. What is more, venomous arthropods such as scorpions, bees, wasps, spiders, ants, centipedes, snail, beetles, and caterpillars. The venoms and toxins from these arthropods provide a promising source of natural bioactive compounds which can be employed in the development of new drugs to treat diseases as cancer. The possibility of using these active molecules in biotechnological processes can

  16. Fauna parasitária de tambaqui Colossoma macropomum (Characidae cultivado em tanque-rede no estado do Amapá, Amazônia oriental Parasitic fauna of tambaqui Colossoma macropomum(Characidae farmed in cages in the State of Amapá, eastern Amazon

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    Evandro Freitas Santos

    2013-03-01

    Full Text Available O objetivo principal deste trabalho foi estudar a parasitofauna e a relação hospedeiro- parasito em tambaqui Colossoma macropomum cultivados em tanques-rede no Rio Matapi, município de Santana, estado do Amapá, região da Amazônia oriental, Brasil. Foram examinados 60 tambaquis, dos quais 96,7% estavam parasitados por protozoários Ichthyophthirius multifiliis (Ciliophora e Piscinoodinium pillulare (Dinoflagellida, monogenoideas Mymarotheciun boegeri e Anacanthorus spathulatus (Dactylogyridae e sanguessugas Glossiiphonidae gen. sp. (Hirudinea. Os maiores níveis de parasitismo foram causados por protozoários I. multifiliis e P. pillulare e os menores por sanguessugas Glossiiphonidae gen. sp. Porém, os índices de infestação não tiveram efeitos na saúde dos peixes hospedeiros, uma vez que o fator de condição relativo (Kn não foi estatisticamente (pThe purpose of this paper was to evaluate the parasitic fauna and the host-parasite relationship in Colossoma macropomum farmed in cages of Matapi River, municipally of Santana, State of Amapá, in eastern Amazon, Brazil. Of 60 specimens of tambaqui examined, 96.7% were parasitized by protozoans Ichthyophthirius multifiliis (Ciliophora and Piscinoodinium pillulare (Dinoflagellida, monogenoideans Mymarotheciun boegeri and Anacanthorus spathulatus (Dactylogyridae, and leeches Glossiphoniidae gen. sp. (Hirudinea. The higher infestation levels were caused by protozoans I. multifiliis and P. pillulare, while the lower infestation levels were caused by leeches. No effects of parasitic infestation rates on fish health were observed. The relative condition factor (Kn was not correlated with the intensity of parasites found. This was the first record of I. multifiliis and P. pillulare in C. macropomum farmed in cages in the Brazilian Amazon.

  17. Standardized protocol for artery-only fingertip replantation.

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    Buntic, Rudolf F; Brooks, Darrell

    2010-09-01

    Artery-only fingertip replantation can be reliable if low-resistance flow through the replant is maintained until venous outflow is restored naturally. Injuring the tip of the replant to promote ongoing bleeding augmented with anticoagulation usually accomplishes this; however, such management results in prolonged hospitalization. In this study, we analyzed the outcomes of artery-only fingertip replantation using a standardized postoperative protocol consisting of dextran-40, heparin, and leech therapy. Between 2001 and 2008, we performed 19 artery-only fingertip replants for 17 patients. All patients had the replanted nail plate removed and received intravenous dextran-40, heparin, and aspirin to promote fingertip bleeding and vascular outflow. Anticoagulation was titrated to promote a controlled bleed until physiologic venous outflow was restored by neovascularization. We used medicinal leeches and mechanical heparin scrubbing for acute decongestion. By postoperative day 6, bleeding was no longer promoted. We initiated fluorescent dye perfusion studies to assess circulatory competence and direct further anticoagulant intervention if necessary. The absence of bleeding associated with an initial rise followed by an appropriate fall in fluorescent dye concentration would trigger a weaning of anticoagulation. All of the 19 replants survived. The average length of hospital stay was 9 days (range, 7-17 d). Eleven patients received blood transfusions. The average transfusion was 1.8 units (range, 0-9 units). All patients were happy with the decision to replant, and the cosmetic result. A protocol that promotes temporary, controlled bleeding from the fingertip is protective of artery-only replants distal to the distal interphalangeal joint until physiologic venous outflow is restored. The protocol described is both safe and reliable. The patient should be informed that such replant attempts may result in the need for transfusions and extended hospital stays, factors that

  18. Multiple venous anastomoses decrease the need for intensive postoperative management in tamai zone I replantations

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    Deok Hyeon Ryu

    2018-01-01

    Full Text Available Background Venous anastomosis is an important component of digital replantation, but is not always feasible, as some cases require external bleeding to treat venous congestion in the replanted tissue. In the present study, we evaluated the relationship between the number of vein anastomoses and the survival rate of Tamai zone I replantations. Methods A retrospective review was performed of all patients who underwent replantation of a fingertip amputation between 2014 and 2016. Patient charts were reviewed for demographic information, the mechanism of injury, the number of venous anastomoses, and the use of anticoagulation, external bleeding, and/or leeches. The cohort was divided into 3 groups depending on the number of venous anastomoses: no veins (group 1, a single vein (group 2, and 2 or more veins (group 3. Survival rates and external bleeding rates were analyzed across the groups. Results The review identified 143 fingertip replantations among 134 patients. The overall survival rate was 94% (135 of 143. Failures were due equally to venous complications (n=4, 50% and to arterial complications (n=4, 50%. Our analysis did not identify any correlation between the number of veins anastomosed and the replant survival rate (P=0.689. However, a greater number of anastomoses was associated with a significantly lower frequency of external bleeding (P=0.017. Conclusions The number of venous anastomoses was not correlated with the survival rate. However, a greater number of venous anastomoses was associated with a decreased need for external bleeding, corresponding to a significant decrease in the need for postoperative monitoring and leech therapy.

  19. Multiple venous anastomoses decrease the need for intensive postoperative management in tamai zone I replantations

    Science.gov (United States)

    Ryu, Deok Hyeon; Roh, Si Young; Kim, Jin Soo; Lee, Dong Chul; Lee, Kyung Jin

    2018-01-01

    Background Venous anastomosis is an important component of digital replantation, but is not always feasible, as some cases require external bleeding to treat venous congestion in the replanted tissue. In the present study, we evaluated the relationship between the number of vein anastomoses and the survival rate of Tamai zone I replantations. Methods A retrospective review was performed of all patients who underwent replantation of a fingertip amputation between 2014 and 2016. Patient charts were reviewed for demographic information, the mechanism of injury, the number of venous anastomoses, and the use of anticoagulation, external bleeding, and/or leeches. The cohort was divided into 3 groups depending on the number of venous anastomoses: no veins (group 1), a single vein (group 2), and 2 or more veins (group 3). Survival rates and external bleeding rates were analyzed across the groups. Results The review identified 143 fingertip replantations among 134 patients. The overall survival rate was 94% (135 of 143). Failures were due equally to venous complications (n=4, 50%) and to arterial complications (n=4, 50%). Our analysis did not identify any correlation between the number of veins anastomosed and the replant survival rate (P=0.689). However, a greater number of anastomoses was associated with a significantly lower frequency of external bleeding (P=0.017). Conclusions The number of venous anastomoses was not correlated with the survival rate. However, a greater number of venous anastomoses was associated with a decreased need for external bleeding, corresponding to a significant decrease in the need for postoperative monitoring and leech therapy. PMID:29076329

  20. Phylogeny and revision of Erpobdelliformes (Annelida, Arhynchobdellida from Mexico based on nuclear and mithochondrial gene sequences. Filogenia y revisión de los Erpobdelliformes (Annelida, Arhynchobdellida de México, con base en secuencias de ADN nuclear y mitocondrial

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    Alejandro Oceguera-Figueroa

    2005-12-01

    Full Text Available The phylogenetic relationships of the suborder Erpobdelliformes, a group of non-sanguivorous leeches, were investigated with the use of mitochondrial cytochrome c oxidase subunit I, mitochondrial 12S rDNA and nuclear 18S rDNA. The resulting hypothesis indicates that Erpobdellidae and Salifidae are monophyletic and each other closest relatives. We detect, for first time in leeches, intra-specific variation of similar amount than inter-specific variation. We formally resurrect the name Erpobdella mexicana, proposed by Dugès for Mexican specimens, and recommend the use of the name Erpobdella ochoterenai rather than Erpobdella microstoma for Mexican specimens. We record an invasive species of the family Salifidae: Barbronia arcana in Mexico, representing the first record of the species outside Australia, first record of the family in Mexico and third in the New World.Se estudian las relaciones filogenéticas del suborden Erpobdelliformes, un grupo de sanguijuelas no hematófagas de vertebrados, con base en secuencias de la subunidad I del citocromo c oxidasa del ADN mitocondrial, 12S ADNr del ADN mitocondrial y 18S ADNr del ADN nuclear. La hipótesis resultante señala que las familias Salifidae y Erpobdellidae son monofiléticas y hermanas entre sí. Se detecta por primera vez en sanguijuelas variación interespecífica de magnitud similar a la variación interespecífica. Formalmente se reslece el nombre empleado por Dugès: Erpobdella mexicana para las formas mexicanas, así como se argumenta sobre el uso del nombre Erpobdella ochoterenai en lugar de Erpobdella microstoma para las formas mexicanas. Se registra a una especie invasora de la familia Salifidae en México: Barbronia arcana, el cual constituye el primer registro de la especie fuera de Australia, primer registro de la familia en México y tercero en el continente americano.

  1. Treatment by bloodletting in the past and present

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    Čolović Nataša

    2016-01-01

    Full Text Available Introduction. Therapeutic bloodletting has been practiced at least 3000 years as one of the most frequent methods of treatment in general, whose value was not questioned until the 19th century, when it was gradually abandoned in Western medicine, while it is still practiced in Arabic and traditional Chinese medicine. Content. In modern medicine bloodletting is practiced for very few indications. Its concept was modeled on the process of menstrual bleeding, for which it was believed to “purge women of bad humours.” Thus, bloodletting was based more on the belief that it helps in the reestablishment of proper balance of body “humours” than on the opinion that it serves to remove excessive amount of blood as well as to remove toxic “pneumas” that accumulate in human body. It was indicated for almost all known diseases, even in the presence of severe anemia. Bloodletting was carried out by scarification with cupping, by phlebotomies (venesections, rarely by arteriotomies, using specific instruments called lancets, as well as leeches. In different periods of history bloodletting was practiced by priests, doctors, barbers, and even by amateurs. In most cases, between one half of liter and two liters of blood used to be removed. Bloodletting was harmful to vast majority of patients and in some of them it is believed that it was either fatal or that it strongly contributed to such outcome. In the 20th century in the “Western” medicine bloodletting was still practiced in the treatment of hypertension and in severe cardiac insufficiency and pulmonary edema, but these indications were later abandoned. Conclusion. Bloodletting is still indicated for a few indications such as polycythemia, haemochromatosis, and porphyria cutanea tarda, while leeches are still used in plastic surgery, replantation and other reconstructive surgery, and very rarely for other specific indications.

  2. The genome sequence of the protostome Daphnia pulex encodes respective orthologues of a neurotrophin, a Trk and a p75NTR: Evolution of neurotrophin signaling components and related proteins in the bilateria

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    Wilson Karen HS

    2009-10-01

    Full Text Available Abstract Background Neurotrophins and their Trk and p75NTR receptors play an important role in the nervous system. To date, neurotrophins, Trk and p75NTR have only been found concomitantly in deuterostomes. In protostomes, homologues to either neurotrophin, Trk or p75NTR are reported but their phylogenetic relationship to deuterostome neurotrophin signaling components is unclear. Drosophila has neurotrophin homologues called Spätzles (Spz, some of which were recently renamed neurotrophins, but direct proof that these are deuterostome neurotrophin orthologues is lacking. Trks belong to the receptor tyrosine kinase (RTK family and among RTKs, Trks and RORs are closest related. Flies lack Trks but have ROR and ROR-related proteins called NRKs playing a neurotrophic role. Mollusks have so far the most similar proteins to Trks (Lymnaea Trk and Aplysia Trkl but the exact phylogenetic relationship of mollusk Trks to each other and to vertebrate Trks is unknown. p75NTR belongs to the tumor necrosis factor receptor (TNFR superfamily. The divergence of the TNFR families in vertebrates has been suggested to parallel the emergence of the adaptive immune system. Only one TNFR representative, the Drosophila Wengen, has been found in protostomes. To clarify the evolution of neurotrophin signaling components in bilateria, this work analyzes the genome of the crustacean Daphnia pulex as well as new genetic data from protostomes. Results The Daphnia genome encodes a neurotrophin, p75NTR and Trk orthologue together with Trkl, ROR, and NRK-RTKs. Drosophila Spz1, 2, 3, 5, 6 orthologues as well as two new groups of Spz proteins (Spz7 and 8 are also found in the Daphnia genome. Searching genbank and the genomes of Capitella, Helobdella and Lottia reveals neurotrophin signaling components in other protostomes. Conclusion It appears that a neurotrophin, Trk and p75NTR existed at the protostome/deuterostome split. In protostomes, a "neurotrophin superfamily" includes

  3. Biogeochemistry of uranium in the soil-plant and water-plant systems in an old uranium mine

    International Nuclear Information System (INIS)

    Favas, Paulo J.C.; Pratas, João; Mitra, Soumita; Sarkar, Santosh Kumar; Venkatachalam, Perumal

    2016-01-01

    The present study highlights the uranium (U) concentrations in water–soil–plant matrices and the efficiency considering a heterogeneous assemblage of terrestrial and aquatic native plant species to act as the biomonitor and phytoremediator for environmental U-contamination in the Sevilha mine (uraniferous region of Beiras, Central Portugal). A total of 53 plant species belonging to 22 families was collected from 24 study sites along with ambient soil and/or water samples. The concentration of U showed wide range of variations in the ambient medium: 7.5 to 557 mg kg"− "1 for soil and 0.4 to 113 μg L"− "1 for water. The maximum potential of U accumulation was recorded in roots of the following terrestrial plants: Juncus squarrosus (450 mg kg"− "1 DW), Carlina corymbosa (181 mg kg"− "1 DW) and Juncus bufonius (39.9 mg kg"− "1 DW), followed by the aquatic macrophytes, namely Callitriche stagnalis (55.6 mg kg"− "1 DW) Lemna minor (53.0 mg kg"− "1 DW) and Riccia fluitans (50.6 mg kg"− "1 DW). Accumulation of U in plant tissues exhibited the following decreasing trend: root > leaves > stem > flowers/fruits and this confirms the unique efficiency of roots in accumulating this radionuclide from host soil/sediment (phytostabilization). Overall, the accumulation pattern in the studied aquatic plants (L. minor, R. fluitans, C. stagnalis and Lythrum portula) dominated over most of the terrestrial counterpart. Among terrestrial plants, the higher mean bioconcentration factor (≈ 1 in roots/rhizomes of C. corymbosa and J. squarrosus) and translocation factor (31 in Andryala integrifolia) were encountered in the representing families Asteraceae and Juncaceae. Hence, these terrestrial plants can be treated as the promising candidates for the development of the phytostabilization or phytoextraction methodologies based on the accumulation, abundance and biomass production. - Highlights: • The uranium (U) accumulation efficiency of terrestrial and aquatic

  4. Biogeochemistry of uranium in the soil-plant and water-plant systems in an old uranium mine

    Energy Technology Data Exchange (ETDEWEB)

    Favas, Paulo J.C., E-mail: pjcf@utad.pt [University of Trás-os-Montes e Alto Douro, UTAD, School of Life Sciences and the Environment, Quinta de Prados, 5000-801 Vila Real (Portugal); MARE, Marine and Environmental Sciences Centre, Faculty of Sciences and Technology, University of Coimbra, 3004-517 Coimbra (Portugal); Pratas, João [MARE, Marine and Environmental Sciences Centre, Faculty of Sciences and Technology, University of Coimbra, 3004-517 Coimbra (Portugal); University of Coimbra, Faculty of Sciences and Technology, Department of Earth Sciences, 3001-401 Coimbra (Portugal); Instituto de Geologia e Petróleo de Timor Leste, Timor-Leste (Country Unknown); Mitra, Soumita; Sarkar, Santosh Kumar [University of Calcutta, Department of Marine Science, 35, Ballygunge Circular Road, Calcutta 700019, West Bengal (India); Venkatachalam, Perumal [Periyar University, Department of Biotechnology, Salem 636 011, TN (India)

    2016-10-15

    The present study highlights the uranium (U) concentrations in water–soil–plant matrices and the efficiency considering a heterogeneous assemblage of terrestrial and aquatic native plant species to act as the biomonitor and phytoremediator for environmental U-contamination in the Sevilha mine (uraniferous region of Beiras, Central Portugal). A total of 53 plant species belonging to 22 families was collected from 24 study sites along with ambient soil and/or water samples. The concentration of U showed wide range of variations in the ambient medium: 7.5 to 557 mg kg{sup −} {sup 1} for soil and 0.4 to 113 μg L{sup −} {sup 1} for water. The maximum potential of U accumulation was recorded in roots of the following terrestrial plants: Juncus squarrosus (450 mg kg{sup −} {sup 1} DW), Carlina corymbosa (181 mg kg{sup −} {sup 1} DW) and Juncus bufonius (39.9 mg kg{sup −} {sup 1} DW), followed by the aquatic macrophytes, namely Callitriche stagnalis (55.6 mg kg{sup −} {sup 1} DW) Lemna minor (53.0 mg kg{sup −} {sup 1} DW) and Riccia fluitans (50.6 mg kg{sup −} {sup 1} DW). Accumulation of U in plant tissues exhibited the following decreasing trend: root > leaves > stem > flowers/fruits and this confirms the unique efficiency of roots in accumulating this radionuclide from host soil/sediment (phytostabilization). Overall, the accumulation pattern in the studied aquatic plants (L. minor, R. fluitans, C. stagnalis and Lythrum portula) dominated over most of the terrestrial counterpart. Among terrestrial plants, the higher mean bioconcentration factor (≈ 1 in roots/rhizomes of C. corymbosa and J. squarrosus) and translocation factor (31 in Andryala integrifolia) were encountered in the representing families Asteraceae and Juncaceae. Hence, these terrestrial plants can be treated as the promising candidates for the development of the phytostabilization or phytoextraction methodologies based on the accumulation, abundance and biomass production

  5. Phospholipase A2 - nexus of aging, oxidative stress, neuronal excitability, and functional decline of the aging nervous system? Insights from a snail model system of neuronal aging and age-associated memory impairment.

    Science.gov (United States)

    Hermann, Petra M; Watson, Shawn N; Wildering, Willem C

    2014-01-01

    The aging brain undergoes a range of changes varying from subtle structural and physiological changes causing only minor functional decline under healthy normal aging conditions, to severe cognitive or neurological impairment associated with extensive loss of neurons and circuits due to age-associated neurodegenerative disease conditions. Understanding how biological aging processes affect the brain and how they contribute to the onset and progress of age-associated neurodegenerative diseases is a core research goal in contemporary neuroscience. This review focuses on the idea that changes in intrinsic neuronal electrical excitability associated with (per)oxidation of membrane lipids and activation of phospholipase A2 (PLA2) enzymes are an important mechanism of learning and memory failure under normal aging conditions. Specifically, in the context of this special issue on the biology of cognitive aging we portray the opportunities offered by the identifiable neurons and behaviorally characterized neural circuits of the freshwater snail Lymnaea stagnalis in neuronal aging research and recapitulate recent insights indicating a key role of lipid peroxidation-induced PLA2 as instruments of aging, oxidative stress and inflammation in age-associated neuronal and memory impairment in this model system. The findings are discussed in view of accumulating evidence suggesting involvement of analogous mechanisms in the etiology of age-associated dysfunction and disease of the human and mammalian brain.

  6. Mitochondrial Insult in a Parkinson's like symptoms model

    Science.gov (United States)

    Carrizales, Julio; Cantu, Manuel; Plas, Daniel; Daniel Plas Lab Team, Dr.

    2014-03-01

    Healthy cells require healthy mitochondria. If these organelles are damaged, many health consequences follow. For example, Parkinson's Disease (PD) is a major neurodegenerative disorder of unknown cause, but much evidence points to the mitochondrion as a key player in the onset of this disease. PD has been studied in animal models challenged with toxins that target the mitochondria. In our work, we have used the pesticide, Rotenone, a known inhibitor of protein Complex I in the mitochondrial electron transport chain. When this toxin is applied to the freshwater mollusk, Lymnaea stagnalis, or pond snail, severe motor deficits ensue. In this project, we are studying the direct effects of this toxin on mitochondrial structure and physiology. We expected that the morphology of the organelle may be altered. In addition, it is likely that the mitochondrial membrane potential necessary for normal function may decrease as the electron transport loses the ability to move protons from the matrix to the intermembrane space. we also are going to use Electrophysiology to compare and Identify the difference of the electrical signaling among healthy and unhealthy neurons. HHMI

  7. Natural selection on immune defense: A field experiment.

    Science.gov (United States)

    Langeloh, Laura; Behrmann-Godel, Jasminca; Seppälä, Otto

    2017-02-01

    Predicting the evolution of phenotypic traits requires an understanding of natural selection on them. Despite its indispensability in the fight against parasites, selection on host immune defense has remained understudied. Theory predicts immune traits to be under stabilizing selection due to associated trade-offs with other fitness-related traits. Empirical studies, however, report mainly positive directional selection. This discrepancy could be caused by low phenotypic variation in the examined individuals and/or variation in host resource level that confounds trade-offs in empirical studies. In a field experiment where we maintained Lymnaea stagnalis snails individually in cages in a lake, we investigated phenotypic selection on two immune defense traits, phenoloxidase (PO)-like activity and antibacterial activity, in hemolymph. We used a diverse laboratory population and manipulated snail resource level by limiting their food supply. For six weeks, we followed immune activity, growth, and two fitness components, survival and fecundity of snails. We found that PO-like activity and growth were under stabilizing selection, while antibacterial activity was under positive directional selection. Selection on immune traits was mainly driven by variation in survival. The form of selection on immune defense apparently depends on the particular trait, possibly due to its importance for countering the present parasite community. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

  8. Weak involvement of octopamine in aversive taste learning in a snail.

    Science.gov (United States)

    Aonuma, Hitoshi; Kaneda, Mugiho; Hatakeyama, Dai; Watanabe, Takayuki; Lukowiak, Ken; Ito, Etsuro

    2017-05-01

    The pond snail Lymnaea stagnalis is capable of learning taste aversion by pairing presentations of a sucrose solution and an electric shock and consolidating it into long-term memory (LTM), which is referred to as conditioned taste aversion (CTA). We asked here if the neurotransmitter octopamine is involved in CTA. We first determined the levels of octopamine and its catabolites in the central nervous system (CNS) of snails with varying degrees of food deprivation, because CTA grades are correlated with degrees of food deprivation. We next manipulated the octopamine signaling using both an agonist and an antagonist of octopamine receptors and correlated their respective effects with CTA grades. We found that snails with the least amount of food-deprivation obtained the best CTA grade and had low levels of octopamine; whereas the most severely food-deprived snails did not form CTA and had the highest CNS octopamine levels. In modestly food-deprived snails, octopamine application increased the basal level of feeding response to a sucrose solution, and it did not obstruct CTA formation. Application of phentolamine, an octopamine receptor antagonist, to the most severely food-deprived snails decreased the basal level of feeding elicited by sucrose, but it did not enhance CTA formation. We conclude that octopamine involvement in CTA formation in Lymnaea is at best weak, and that the changes in CNS octopamine content are an epiphenomenon. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Cerebral Giant Cells are Necessary for the Formation and Recall of Memory of Conditioned Taste Aversion in Lymnaea.

    Science.gov (United States)

    Sunada, Hiroshi; Lukowiak, Ken; Ito, Etsuro

    2017-02-01

    The pond snail Lymnaea stagnalis can acquire conditioned taste aversion (CTA) as a long-term memory. CTA is caused by the temporal pairing of a stimulus, such as sucrose (the conditioned stimulus; CS), with another stimulus, such as electric shock (the unconditioned stimulus; US). Previous studies have demonstrated changes in both cellular and molecular properties in a pair of neurons known as the cerebral giant cells (CGCs), suggesting that these neurons play a key role in CTA. Here we examined the necessity of the pair of CGC somata for the learning, memory formation and memory recall of CTA by using the soma ablation technique. There was no difference in the feeding response elicited by the CS before and after ablation of the CGC somata. Ablation of the CGC somata before taste-aversion training resulted in the learning acquisition, but the memory formation was not observed 24 h later. We next asked whether memory was present when the CGC somata were ablated 24 h after taste-aversion training. The memory was present before performing the somata ablation. However, when we tested snails five days after somata ablation, the memory recall was not present. Together the data show that: 1) the somata of the CGCs are not necessary for learning acquisition; 2) the somata are necessary for memory formation; and 3) the somata are necessary for memory recall. That is, these results demonstrate that the CGCs function in the long-term memory of CTA in Lymnaea.

  10. Consolidation of long-term memory by insulin in Lymnaea is not brought about by changing the number of insulin receptors.

    Science.gov (United States)

    Hatakeyama, Dai; Okuta, Akiko; Otsuka, Emi; Lukowiak, Ken; Ito, Etsuro

    2013-05-01

    The pond snail Lymnaea stagnalis learns taste aversion and consolidates it into long-term memory (LTM). This is referred to as conditioned taste aversion (CTA). The superfusion of molluscan insulin-related peptides (MIPs) over the isolated snail brain causes a long-term enhancement of synaptic input between the cerebral giant cell and the B1 buccal motor neuron. This enhancement is hypothesized to underlie CTA. The synaptic enhancement caused by the superfusion of MIPs can be blocked by the application of human insulin receptor antibody, which recognizes the extracellular domain of human insulin receptor and acts as an antagonist even for MIP receptors. An injection of the human insulin receptor antibody into the abdominal cavity of trained snails blocks the consolidation process leading to LTM, even though the snails acquire taste aversion. Here, we examined whether or not taste-aversion training changes the mRNA expression level of MIP receptor in the snail brain and found that it does not. This result, taken together with previous findings, suggest that the MIPs' effect on synaptic function in the snail brain is attributable to a change in the MIP concentration, and not to a change in the mRNA expression level of MIP receptor, which is thought to reflect the number of MIP receptors.

  11. Function of insulin in snail brain in associative learning.

    Science.gov (United States)

    Kojima, S; Sunada, H; Mita, K; Sakakibara, M; Lukowiak, K; Ito, E

    2015-10-01

    Insulin is well known as a hormone regulating glucose homeostasis across phyla. Although there are insulin-independent mechanisms for glucose uptake in the mammalian brain, which had contributed to a perception of the brain as an insulin-insensitive organ for decades, the finding of insulin and its receptors in the brain revolutionized the concept of insulin signaling in the brain. However, insulin's role in brain functions, such as cognition, attention, and memory, remains unknown. Studies using invertebrates with their open blood-vascular system have the promise of promoting a better understanding of the role played by insulin in mediating/modulating cognitive functions. In this review, the relationship between insulin and its impact on long-term memory (LTM) is discussed particularly in snails. The pond snail Lymnaea stagnalis has the ability to undergo conditioned taste aversion (CTA), that is, it associatively learns and forms LTM not to respond with a feeding response to a food that normally elicits a robust feeding response. We show that molluscan insulin-related peptides are up-regulated in snails exhibiting CTA-LTM and play a key role in the causal neural basis of CTA-LTM. We also survey the relevant literature of the roles played by insulin in learning and memory in other phyla.

  12. The Effect of Diet Mixing on a Nonselective Herbivore.

    Directory of Open Access Journals (Sweden)

    Sophie Groendahl

    Full Text Available The balanced-diet hypothesis states that a diverse prey community is beneficial to consumers due to resource complementarity among the prey species. Nonselective consumer species cannot differentiate between prey items and are therefore not able to actively regulate their diet intake. We thus wanted to test whether the balanced-diet hypothesis is applicable to nonselective consumers. We conducted a laboratory experiment in which a nonselective model grazer, the freshwater gastropod Lymnaea stagnalis, was fed benthic green algae as single species or as a multi-species mixture and quantified the snails' somatic growth rates and shell lengths over a seven-week period. Gastropods fed the mixed diet were found to exhibit a higher somatic growth rate than the average of the snails fed single prey species. However, growth on the multi-species mixture did not exceed the growth rate obtained on the best single prey species. Similar results were obtained regarding the animals' shell height increase over time. The mixed diet did not provide the highest growth rate, which confirms our hypothesis. We thus suggest that the balanced-diet hypothesis is less relevant for non-selective generalist consumers, which needs to be considered in estimates of secondary production.

  13. Synthesis of isotopically modified ZnO nanoparticles and their potential as nanotoxicity tracers

    Energy Technology Data Exchange (ETDEWEB)

    Dybowska, Agnieszka D., E-mail: a.dybowska@nhm.ac.u [Department of Mineralogy, Natural History Museum London, Cromwell Road, London, SW7 5BD (United Kingdom); Croteau, Marie-Noele [U.S. Geological Survey, 345 Middlefield Road, MS 496, Menlo Park, CA 94025 (United States); Misra, Superb K.; Berhanu, Deborah [Department of Mineralogy, Natural History Museum London, Cromwell Road, London, SW7 5BD (United Kingdom); Luoma, Samuel N. [Department of Mineralogy, Natural History Museum London, Cromwell Road, London, SW7 5BD (United Kingdom); U.S. Geological Survey, 345 Middlefield Road, MS 496, Menlo Park, CA 94025 (United States); Christian, Paul; O' Brien, Paul [School of Chemistry, University of Manchester, M13 9PL, Manchester (United Kingdom); Valsami-Jones, Eugenia [Department of Mineralogy, Natural History Museum London, Cromwell Road, London, SW7 5BD (United Kingdom)

    2011-01-15

    Understanding the behavior of engineered nanoparticles in the environment and within organisms is perhaps the biggest obstacle to the safe development of nanotechnologies. Reliable tracing is a particular issue for nanoparticles such as ZnO, because Zn is an essential element and a common pollutant thus present at elevated background concentrations. We synthesized isotopically enriched (89.6%) with a rare isotope of Zn ({sup 67}Zn) ZnO nanoparticles and measured the uptake of {sup 67}Zn by L. stagnalis exposed to diatoms amended with the particles. Stable isotope technique is sufficiently sensitive to determine the uptake of Zn at an exposure equivalent to lower concentration range (<15 {mu}g g{sup -1}). Without a tracer, detection of newly accumulated Zn is significant at Zn exposure concentration only above 5000 {mu}g g{sup -1} which represents some of the most contaminated Zn conditions. Only by using a tracer we can study Zn uptake at a range of environmentally realistic exposure conditions. - ZnO nanoparticles with distinct isotopic composition can be tailor synthesized to be used as tracers of environmental fate and uptake by organisms.

  14. Synthesis of isotopically modified ZnO nanoparticles and their potential as nanotoxicity tracers.

    Science.gov (United States)

    Dybowska, Agnieszka D; Croteau, Marie-Noele; Misra, Superb K; Berhanu, Deborah; Luoma, Samuel N; Christian, Paul; O'Brien, Paul; Valsami-Jones, Eugenia

    2011-01-01

    Understanding the behavior of engineered nanoparticles in the environment and within organisms is perhaps the biggest obstacle to the safe development of nanotechnologies. Reliable tracing is a particular issue for nanoparticles such as ZnO, because Zn is an essential element and a common pollutant thus present at elevated background concentrations. We synthesized isotopically enriched (89.6%) with a rare isotope of Zn (67Zn) ZnO nanoparticles and measured the uptake of 67Zn by L. stagnalis exposed to diatoms amended with the particles. Stable isotope technique is sufficiently sensitive to determine the uptake of Zn at an exposure equivalent to lower concentration range (<15 μg g(-1)). Without a tracer, detection of newly accumulated Zn is significant at Zn exposure concentration only above 5000 μg g(-1) which represents some of the most contaminated Zn conditions. Only by using a tracer we can study Zn uptake at a range of environmentally realistic exposure conditions. Copyright © 2010 Elsevier Ltd. All rights reserved.

  15. Small-sized euryhaline fish as intermediate hosts of the digenetic trematode Cryptocotyle concavum

    Science.gov (United States)

    Zander, C. D.; Kollra, H.-G.; Antholz, B.; Meyer, W.; Westphal, D.

    1984-03-01

    Cercariae of the trematode Cryptocotyle concavum, which encyst in skin and/or kidney of sticklebacks and gobies, were studied in the Schlei Fjord (western Baltic Sea). Mean incidence of dermal cysts was 48 % in Gasterosteus aculeatus and 37 % in Pungitius pungitius. No cysts were found in the kidneys of sticklebacks. While 97 % of Pomatoschistus microps had encysted metacercariae in the kidneys, only 2 % had cysts in the skin. Pomatoschistus minutus, however, showed hardly any cyst infestation of either skin or kidney. In P. microps the intensity of infestation by metacercariae was frequently more than 50 cysts; in contrast, sticklebacks rarely exhibited more than 5 dermal cysts. Infested fish were larger than 10 mm in total length, the incidence rate increasing with growth. Parasitic infestation depends on ambient salinity: C. concavum was not found at salinities below 4 ‰. In contrast to the high incidence in fish, the first hosts — the snails Hydrobia stagnalis and H. neglecta — showed remarkably low infection rates (3 to 5 %). The findings reported are related to the distribution of C. concavum, the mode of life of infested fish, the feeding habits of the final hosts and the infestation of P. microps by other parasites. Evidently, P. microps represents an optimal second host for C. concavum.

  16. Simultaneous analysis of multiple neurotransmitters by hydrophilic interaction liquid chromatography coupled to tandem mass spectrometry.

    Science.gov (United States)

    Tufi, Sara; Lamoree, Marja; de Boer, Jacob; Leonards, Pim

    2015-05-22

    Neurotransmitters are endogenous metabolites that allow the signal transmission across neuronal synapses. Their biological role is crucial for many physiological functions and their levels can be changed by several diseases. Because of their high polarity, hydrophilic interaction liquid chromatography (HILIC) is a promising tool for neurotransmitter analysis. Due to the large number of HILIC stationary phases available, an evaluation of the column performances and retention behaviors has been performed on five different commercial HILIC packing materials (silica, amino, amide and two zwitterionic stationary phases). Several parameters like the linear correlation between retention and the distribution coefficient (logD), the separation factor k and the column resolution Rs have been investigated and the column performances have been visualized with a heat map and hierarchical clustering analysis. An optimized and validated HILIC-MS/MS method based on the ZIC-cHILIC column is proposed for the simultaneous detection and quantification of twenty compounds consisting of neurotransmitters, precursors and metabolites: 3-methoxytyramine (3-MT), 5-hydroxyindoleacetic acid (5-HIAA), 5-hydroxy-L-tripthophan, acetylcholine, choline, L-3,4-dihydroxyphenylalanine (L-DOPA), dopamine, epinephrine, γ-aminobutyric acid (GABA), glutamate, glutamine, histamine, histidine, L-tryptophan, L-tyrosine, norepinephrine, normetanephrine, phenylalanine, serotonin and tyramine. The method was applied to neuronal metabolite profiling of the central nervous system of the freshwater snail Lymnaea stagnalis. This method is suitable to explore neuronal metabolism and its alteration in different biological matrices. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Synthesis of isotopically modified ZnO nanoparticles and their potential as nanotoxicity tracers

    International Nuclear Information System (INIS)

    Dybowska, Agnieszka D.; Croteau, Marie-Noele; Misra, Superb K.; Berhanu, Deborah; Luoma, Samuel N.; Christian, Paul; O'Brien, Paul; Valsami-Jones, Eugenia

    2011-01-01

    Understanding the behavior of engineered nanoparticles in the environment and within organisms is perhaps the biggest obstacle to the safe development of nanotechnologies. Reliable tracing is a particular issue for nanoparticles such as ZnO, because Zn is an essential element and a common pollutant thus present at elevated background concentrations. We synthesized isotopically enriched (89.6%) with a rare isotope of Zn ( 67 Zn) ZnO nanoparticles and measured the uptake of 67 Zn by L. stagnalis exposed to diatoms amended with the particles. Stable isotope technique is sufficiently sensitive to determine the uptake of Zn at an exposure equivalent to lower concentration range ( -1 ). Without a tracer, detection of newly accumulated Zn is significant at Zn exposure concentration only above 5000 μg g -1 which represents some of the most contaminated Zn conditions. Only by using a tracer we can study Zn uptake at a range of environmentally realistic exposure conditions. - ZnO nanoparticles with distinct isotopic composition can be tailor synthesized to be used as tracers of environmental fate and uptake by organisms.

  18. Fine Mapping of the Pond Snail Left-Right Asymmetry (Chirality) Locus Using RAD-Seq and Fibre-FISH

    Science.gov (United States)

    Han, Jie; Yang, Fengtang; Aboobaker, Aziz; Blaxter, Mark L.; Davison, Angus

    2013-01-01

    The left-right asymmetry of snails, including the direction of shell coiling, is determined by the delayed effect of a maternal gene on the chiral twist that takes place during early embryonic cell divisions. Yet, despite being a well-established classical problem, the identity of the gene and the means by which left-right asymmetry is established in snails remain unknown. We here demonstrate the power of new genomic approaches for identification of the chirality gene, “D”. First, heterozygous (Dd) pond snails Lymnaea stagnalis were self-fertilised or backcrossed, and the genotype of more than six thousand offspring inferred, either dextral (DD/Dd) or sinistral (dd). Then, twenty of the offspring were used for Restriction-site-Associated DNA Sequencing (RAD-Seq) to identify anonymous molecular markers that are linked to the chirality locus. A local genetic map was constructed by genotyping three flanking markers in over three thousand snails. The three markers lie either side of the chirality locus, with one very tightly linked (chirality gene and the variation that underpins sinistral and dextral coiling. More generally, the results also show that combining genomic technologies, such as RAD-Seq and high resolution FISH, is a robust approach for mapping key loci in non-model systems. PMID:23951082

  19. Diaphanous gene mutation affects spiral cleavage and chirality in snails

    Science.gov (United States)

    Kuroda, Reiko; Fujikura, Kohei; Abe, Masanori; Hosoiri, Yuji; Asakawa, Shuichi; Shimizu, Miho; Umeda, Shin; Ichikawa, Futaba; Takahashi, Hiromi

    2016-01-01

    L-R (left and right) symmetry breaking during embryogenesis and the establishment of asymmetric body plan are key issues in developmental biology, but the onset including the handedness-determining gene locus still remains unknown. Using pure dextral (DD) and sinistral (dd) strains of the pond snail Lymnaea stagnalis as well as its F2 through to F10 backcrossed lines, the single handedness-determining-gene locus was mapped by genetic linkage analysis, BAC cloning and chromosome walking. We have identified the actin-related diaphanous gene Lsdia1 as the strongest candidate. Although the cDNA and derived amino acid sequences of the tandemly duplicated Lsdia1 and Lsdia2 genes are very similar, we could discriminate the two genes/proteins in our molecular biology experiments. The Lsdia1 gene of the sinistral strain carries a frameshift mutation that abrogates full-length LsDia1 protein expression. In the dextral strain, it is already translated prior to oviposition. Expression of Lsdia1 (only in the dextral strain) and Lsdia2 (in both chirality) decreases after the 1-cell stage, with no asymmetric localization throughout. The evolutionary relationships among body handedness, SD/SI (spiral deformation/spindle inclination) at the third cleavage, and expression of diaphanous proteins are discussed in comparison with three other pond snails (L. peregra, Physa acuta and Indoplanorbis exustus). PMID:27708420

  20. Impairing DNA methylation obstructs memory enhancement for at least 24 hours in Lymnaea.

    Science.gov (United States)

    Rothwell, Cailin M; Lukowiak, Ken D

    2017-01-01

    Stressor-induced memory enhancement has previously been shown to involve DNA methylation in the mollusc Lymnaea stagnalis . Specifically, injection of the DNA methylation inhibitor 5-AZA one hour before exposure to a memory-enhancing stressor obstructs memory augmentation. However, the duration of the influence of 5-AZA on this memory enhancement has not yet been examined. In this study, 2 memory-enhancing stressors (a thermal stress and exposure to the scent of a predator) were used to examine whether injection of the DNA methylation inhibitor 5-AZA 24 hours before stress exposure would still impair memory enhancement. Indeed, it was observed that memory is still obstructed when 5-AZA is injected 24 hours before exposure to either of these stressors in Lymnaea . Understanding that 5-AZA still effectively impairs memory enhancement after a period of 24 hours is valuable because it indicates that experimental manipulations do not need to be made within one hour after the injection of this DNA methylation inhibitor and can instead be made within one day (i.e. 24 hours). These results will allow for a future examination of the possible involvement of DNA methylation in memory enhancement related to longer-term stressors or environmental changes. This study further elucidates the involvement of epigenetic changes in memory enhancement in Lymnaea , providing insight into the process of memory formation in this mollusc.

  1. Phospholipase A2 - nexus of aging, oxidative stress, neuronal excitability and functional decline of the aging nervous system? Insights from a snail model system of neuronal aging and age-associated memory impairment.

    Directory of Open Access Journals (Sweden)

    Petra Maria Hermann

    2014-12-01

    Full Text Available TThe aging brain can undergo a range of changes varying from subtle structural and physiological changes causing only minor functional decline under healthy normal aging conditions, to severe cognitive or neurological impairment associated with extensive loss of neurons and circuits due to age-associated neurodegenerative disease conditions. Understanding how biological aging processes affect the brain and how they contribute to the onset and progress of age-associated neurodegenerative diseases is a core research goal in contemporary neuroscience. This review focuses on the idea that changes in intrinsic neuronal electrical excitability associated with (peroxidation of membrane lipids and activation of phospholipase A2 (PLA2 enzymes are an important mechanism of learning and memory failure under normal aging conditions. Specifically, in the context of this special issue on the Biology of cognitive aging we (1 portray the opportunities offered by the identifiable neurons and behaviorally characterized neural circuits of the freshwater snail Lymnaea stagnalis in neuronal aging research and (2 recapitulate recent insights indicating a key role of lipid peroxidation-induced PLA2 as instruments of aging, oxidative stress and inflammation in age-associated neuronal and memory impairment in this model system. The findings are discussed in view of accumulating evidence suggesting involvement of analogous mechanisms in the etiology of age-associated dysfunction and disease of the human and mammalian brain.

  2. On the role of water and forage in penetration of some radionuclides into the Limnaea organism

    International Nuclear Information System (INIS)

    Marchyulenene, D.P.; Polikarpov, G.G.; AN Ukrainskoj SSR, Sevastopol. Inst. Biologii Yuzhnykh Morej)

    1976-01-01

    The objective of this work was to study under laboratory conditions the significance of elodea (Elodea canadensis Rich.) and aqueous medium in accumulation of strontium-90, cesium-137, cerium-144 and ruthenium-106 by limnetic gastropods (Limnaea Stagnalis L.). The study revealed that only 2 and 5% of strontium-90 and cerium-144 respectively were accumulated in molluscs shell from radioactive food, and 4 and 26% - in the body. The authors believed that higher accumulation levels of cerium-144 and ruthenium-106 in mollusca body when the molluscs are fed with radioactive elodea were caused by high accumulation coefficients (AC) of radionuclides in food, i.e. elodea, and their accumulation in the gastrointestinal tracts of molluscs. To appreciates the significance of elodea and water as sources of radionuclide accumulation by mollusca, strontium-90 and cerium-144 AC in molluscs were estimated in relation to water and elodea. The results obtained indicated that AC of these radionuclides in mollusca was much lower in relation to food than to water

  3. Single-cell analysis of peptide expression and electrophysiology of right parietal neurons involved in male copulation behavior of a simultaneous hermaphrodite.

    Science.gov (United States)

    El Filali, Z; de Boer, P A C M; Pieneman, A W; de Lange, R P J; Jansen, R F; Ter Maat, A; van der Schors, R C; Li, K W; van Straalen, N M; Koene, J M

    2015-12-01

    Male copulation is a complex behavior that requires coordinated communication between the nervous system and the peripheral reproductive organs involved in mating. In hermaphroditic animals, such as the freshwater snail Lymnaea stagnalis, this complexity increases since the animal can behave both as male and female. The performance of the sexual role as a male is coordinated via a neuronal communication regulated by many peptidergic neurons, clustered in the cerebral and pedal ganglia and dispersed in the pleural and parietal ganglia. By combining single-cell matrix-assisted laser mass spectrometry with retrograde staining and electrophysiology, we analyzed neuropeptide expression of single neurons of the right parietal ganglion and their axonal projections into the penial nerve. Based on the neuropeptide profile of these neurons, we were able to reconstruct a chemical map of the right parietal ganglion revealing a striking correlation with the earlier electrophysiological and neuroanatomical studies. Neurons can be divided into two main groups: (i) neurons that express heptapeptides and (ii) neurons that do not. The neuronal projection of the different neurons into the penial nerve reveals a pattern where (spontaneous) activity is related to branching pattern. This heterogeneity in both neurochemical anatomy and branching pattern of the parietal neurons reflects the complexity of the peptidergic neurotransmission involved in the regulation of male mating behavior in this simultaneous hermaphrodite.

  4. Mercury remediation in wetland sediment using zero-valent iron and granular activated carbon.

    Science.gov (United States)

    Lewis, Ariel S; Huntington, Thomas G; Marvin-DiPasquale, Mark C; Amirbahman, Aria

    2016-05-01

    Wetlands are hotspots for production of toxic methylmercury (MeHg) that can bioaccumulate in the food web. The objective of this study was to determine whether the application of zero-valent iron (ZVI) or granular activated carbon (GAC) to wetland sediment could reduce MeHg production and bioavailability to benthic organisms. Field mesocosms were installed in a wetland fringing Hodgdon Pond (Maine, USA), and ZVI and GAC were applied. Pore-water MeHg concentrations were lower in treated compared with untreated mesocosms; however, sediment MeHg, as well as total Hg (THg), concentrations were not significantly different between treated and untreated mesocosms, suggesting that smaller pore-water MeHg concentrations in treated sediment were likely due to adsorption to ZVI and GAC, rather than inhibition of MeHg production. In laboratory experiments with intact vegetated sediment clumps, amendments did not significantly change sediment THg and MeHg concentrations; however, the mean pore-water MeHg and MeHg:THg ratios were lower in the amended sediment than the control. In the laboratory microcosms, snails (Lymnaea stagnalis) accumulated less MeHg in sediment treated with ZVI or GAC. The study results suggest that both GAC and ZVI have potential for reducing MeHg bioaccumulation in wetland sediment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Synthesis of isotopically modified ZnO nanoparticles and their potential as nanotoxicity tracers

    Science.gov (United States)

    Dybowska, A.D.; Croteau, M.-N.; Misra, S.K.; Berhanu, D.; Luoma, S.N.; Christian, P.; O'Brien, P.; Valsami-Jones, E.

    2011-01-01

    Understanding the behavior of engineered nanoparticles in the environment and within organisms is perhaps the biggest obstacle to the safe development of nanotechnologies. Reliable tracing is a particular issue for nanoparticles such as ZnO, because Zn is an essential element and a common pollutant thus present at elevated background concentrations. We synthesized isotopically enriched (89.6%) with a rare isotope of Zn (67Zn) ZnO nanoparticles and measured the uptake of 67Zn by L. stagnalis exposed to diatoms amended with the particles. Stable isotope technique is sufficiently sensitive to determine the uptake of Zn at an exposure equivalent to lower concentration range (<15 ??g g-1). Without a tracer, detection of newly accumulated Zn is significant at Zn exposure concentration only above 5000 ??g g-1 which represents some of the most contaminated Zn conditions. Only by using a tracer we can study Zn uptake at a range of environmentally realistic exposure conditions. ?? 2010 Elsevier Ltd. All rights reserved.

  6. Octopamine increases the excitability of neurons in the snail feeding system by modulation of inward sodium current but not outward potassium currents

    Directory of Open Access Journals (Sweden)

    Szabó Henriette

    2005-12-01

    Full Text Available Abstract Background Although octopamine has long been known to have major roles as both transmitter and modulator in arthropods, it has only recently been shown to be functionally important in molluscs, playing a role as a neurotransmitter in the feeding network of the snail Lymnaea stagnalis. The synaptic potentials cannot explain all the effects of octopamine-containing neurons on the feeding network, and here we test the hypothesis that octopamine is also a neuromodulator. Results The excitability of the B1 and B4 motoneurons in the buccal ganglia to depolarising current clamp pulses is significantly (P IA current and a sustained IK delayed-rectifier current, but neither was modulated by octopamine in any of these three buccal neurons. The fast inward current was eliminated in sodium – free saline and so is likely to be carried by sodium ions. 10 μM octopamine enhanced this current by 33 and 45% in the B1 and B4 motoneurons respectively (P Conclusion We conclude that octopamine is also a neuromodulator in snails, changing the excitability of the buccal neurons. This is supported by the close relationship from the voltage clamp data, through the quantitative simulation, to the action potential threshold, changing the properties of neurons in a rhythmic network. The increase in inward sodium current provides an explanation for the polycyclic modulation of the feeding system by the octopamine-containing interneurons, making feeding easier to initiate and making the feeding bursts more intense.

  7. The suitability of several aquatic snails as intermediate hosts for Angiostrongylus cantonensis.

    Science.gov (United States)

    Yousif, F; Lämmler, G

    1975-10-16

    Sixteen species of aquatic snails of four families were tested by quantitative technique under standardized conditions for their suitability as intermediate hosts for Angiostrongylus cantonensis. These species were the planorbid snails Biomphalaria glabrata, Biomphalaria alexandrina, Planorbis planorbis, Planorbis intermixtus, Bulinus truncatus, Bulinus contortus, Bulinus africanus, Bulinus tropicus and Helisoma sp.; the lymnaeid snails Lymnaea natalensis, Lymnaea tomentosa, Lymnaea stagnalis, and Stagnicola elodes; the physid snail Physa acuta (an Egyptian and a German strain) and the ampullariid snails Marisa cornuarietis and Lanistes carinatus. All these snail species proved to be susceptible to infection with A. cantonensis, and first stage larvae reached the infective third stage in all of them. However, the rate and intensity of infection varied with different species. B. glabrata was the most susceptible snail species with a 100% infection rate and an average percentage recovery of third stage larvae of 26.1. This was followed by S. elodes and B. africanus, with a 100% infection rate and an average percentage recovery of third stage larvae of 15.6 and 14.6 respectively. The rest of snail species proved to be less susceptible. For comparative evaluation of the suitability of the various snail species as intermediate hosts of A. cantonensis a "Capacity Index" was determined. This index should provide a useful method for the evaluation of the suitability of various snails as intermediate hosts of nematode parasites under standardized conditions in the laboratory.

  8. Habitat stability, predation risk and ‘memory syndromes’

    Science.gov (United States)

    Dalesman, S.; Rendle, A.; Dall, S.R.X.

    2015-01-01

    Habitat stability and predation pressure are thought to be major drivers in the evolutionary maintenance of behavioural syndromes, with trait covariance only occurring within specific habitats. However, animals also exhibit behavioural plasticity, often through memory formation. Memory formation across traits may be linked, with covariance in memory traits (memory syndromes) selected under particular environmental conditions. This study tests whether the pond snail, Lymnaea stagnalis, demonstrates consistency among memory traits (‘memory syndrome’) related to threat avoidance and foraging. We used eight populations originating from three different habitat types: i) laboratory populations (stable habitat, predator-free); ii) river populations (fairly stable habitat, fish predation); and iii) ditch populations (unstable habitat, invertebrate predation). At a population level, there was a negative relationship between memories related to threat avoidance and food selectivity, but no consistency within habitat type. At an individual level, covariance between memory traits was dependent on habitat. Laboratory populations showed no covariance among memory traits, whereas river populations showed a positive correlation between food memories, and ditch populations demonstrated a negative relationship between threat memory and food memories. Therefore, selection pressures among habitats appear to act independently on memory trait covariation at an individual level and the average response within a population. PMID:26013966

  9. Habitat stability, predation risk and 'memory syndromes'.

    Science.gov (United States)

    Dalesman, S; Rendle, A; Dall, S R X

    2015-05-27

    Habitat stability and predation pressure are thought to be major drivers in the evolutionary maintenance of behavioural syndromes, with trait covariance only occurring within specific habitats. However, animals also exhibit behavioural plasticity, often through memory formation. Memory formation across traits may be linked, with covariance in memory traits (memory syndromes) selected under particular environmental conditions. This study tests whether the pond snail, Lymnaea stagnalis, demonstrates consistency among memory traits ('memory syndrome') related to threat avoidance and foraging. We used eight populations originating from three different habitat types: i) laboratory populations (stable habitat, predator-free); ii) river populations (fairly stable habitat, fish predation); and iii) ditch populations (unstable habitat, invertebrate predation). At a population level, there was a negative relationship between memories related to threat avoidance and food selectivity, but no consistency within habitat type. At an individual level, covariance between memory traits was dependent on habitat. Laboratory populations showed no covariance among memory traits, whereas river populations showed a positive correlation between food memories, and ditch populations demonstrated a negative relationship between threat memory and food memories. Therefore, selection pressures among habitats appear to act independently on memory trait covariation at an individual level and the average response within a population.

  10. Effects of 5-HT and insulin on learning and memory formation in food-deprived snails.

    Science.gov (United States)

    Aonuma, Hitoshi; Totani, Yuki; Kaneda, Mugiho; Nakamura, Ryota; Watanabe, Takayuki; Hatakeyama, Dai; Dyakonova, Varvara E; Lukowiak, Ken; Ito, Etsuro

    2018-02-01

    The pond snail Lymnaea stagnalis learns conditioned taste aversion (CTA) and consolidates it into long-term memory (LTM). How well they learn and form memory depends on the degree of food deprivation. Serotonin (5-HT) plays an important role in mediating feeding, and insulin enhances the memory consolidation process following CTA training. However, the relationship between these two signaling pathways has not been addressed. We measured the 5-HT content in the central nervous system (CNS) of snails subjected to different durations of food deprivation. One-day food-deprived snails, which exhibit the best learning and memory, had the lowest 5-HT content in the CNS, whereas 5-day food-deprived snails, which do not learn, had a high 5-HT content. Immersing 1-day food-deprived snails in 5-HT impaired learning and memory by causing an increase in 5-HT content, and that the injection of insulin into these snails reversed this impairment. We conclude that insulin rescues the CTA deficit and this may be due to a decrease in the 5-HT content in the CNS of Lymnaea. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. Efficient Expression of Acetylcholine-Binding Protein from Aplysia californica in Bac-to-Bac System

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    Bo Lin

    2014-01-01

    Full Text Available The Bac-to-Bac baculovirus expression system can efficiently produce recombinant proteins, but the system may have to be optimized to achieve high-level expression for different candidate proteins. We reported here the efficient expression of acetylcholine-binding proteins from sea hares Aplysia californica (Ac-AChBP and a convenient method to monitor protein expression level in this expression system. Three key factors affecting expression of Ac-AChBP were optimized for maximizing the yield, which included the cell density, volume of the infecting baculovirus inoculums, and the culturing time of postinfection. We have found it to reach a high yield of ∼5 mg/L, which needs 55 h incubation after infection at the cell density of 2 × 106 cells/mL with an inoculum volume ratio of 1 : 100. The optimized expression system in this study was also applied for expressing another protein Ls-AChBP from Lymnaea stagnalis successfully. Therefore, this established method is helpful to produce high yields of AChBP proteins for X-ray crystallographic structural and functional studies.

  12. Are sick individuals weak competitors? Competitive ability of snails parasitized by a gigantism-inducing trematode.

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    Otto Seppälä

    Full Text Available Parasitized individuals are often expected to be poor competitors because they are weakened by infections. Many trematode species, however, although extensively exploiting their mollusc hosts, also induce gigantism (increased host size by diverting host resources towards growth instead of reproduction. In such systems, alternatively to reduced competitive ability due to negative effects of parasitism on host performance, larger size could allow more efficient resource acquisition and thus increase the relative competitive ability of host individuals. We addressed this hypothesis by testing the effect of a trematode parasite Diplostomum pseudospathaceum on the competitive ability of its snail host Lymnaea stagnalis. We experimentally examined the growth of snails kept in pairs in relation to their infection status and intensity of resource competition (i.e. food availability. We found that parasitized snails grew faster and their reproduction was reduced compared to unparasitized individuals indicating parasite-induced gigantism. However, growth of the snails was faster when competing with parasitized individuals compared to unparasitized snails indicating reduced competitive ability due to parasitism. The latter effect, however, was relatively weak suggesting that the effects of the parasite on snail physiology may partly override each other in determining competitive ability.

  13. Assessing the Dietary Bioavailability of Metals Associated with Natural Particles: Extending the Use of the Reverse Labeling Approach to Zinc.

    Science.gov (United States)

    Croteau, Marie-Noële; Cain, Daniel J; Fuller, Christopher C

    2017-03-07

    We extend the use of a novel tracing technique to quantify the bioavailability of zinc (Zn) associated with natural particles using snails enriched with a less common Zn stable isotope. Lymnaea stagnalis is a model species that has relatively fast Zn uptake rates from the dissolved phase, enabling their rapid enrichment in 67 Zn during the initial phase of labeling. Isotopically enriched snails were subsequently exposed to algae mixed with increasing amounts of metal-rich particles collected from two acid mine drainage impacted rivers. Zinc bioavailability from the natural particles was inferred from calculations of 66 Zn assimilation into the snail's soft tissues. Zinc assimilation efficiency (AE) varied from 28% for the Animas River particles to 45% for the Snake River particles, indicating that particle-bound, or sorbed Zn, was bioavailable from acid mine drainage wastes. The relative binding strength of Zn sorption to the natural particles was inversely related to Zn bioavailability; a finding that would not have been possible without using the reverse labeling approach. Differences in the chemical composition of the particles suggest that their geochemical properties may influence the extent of Zn bioavailability.

  14. Dietary uptake of Cu sorbed to hydrous iron oxide is linked to cellular toxicity and feeding inhibition in a benthic grazer

    Science.gov (United States)

    Cain, Daniel J.; Croteau, Marie-Noele; Fuller, Christopher C.; Ringwood, Amy H.

    2016-01-01

    Whereas feeding inhibition caused by exposure to contaminants has been extensively documented, the underlying mechanism(s) are less well understood. For this study, the behavior of several key feeding processes, including ingestion rate and assimilation efficiency, that affect the dietary uptake of Cu were evaluated in the benthic grazer Lymnaea stagnalis following 4–5 h exposures to Cu adsorbed to synthetic hydrous ferric oxide (Cu–HFO). The particles were mixed with a cultured alga to create algal mats with Cu exposures spanning nearly 3 orders of magnitude at variable or constant Fe concentrations, thereby allowing first order and interactive effects of Cu and Fe to be evaluated. Results showed that Cu influx rates and ingestion rates decreased as Cu exposures of the algal mat mixture exceeded 104 nmol/g. Ingestion rate appeared to exert primary control on the Cu influx rate. Lysosomal destabilization rates increased directly with Cu influx rates. At the highest Cu exposure where the incidence of lysosomal membrane damage was greatest (51%), the ingestion rate was suppressed 80%. The findings suggested that feeding inhibition was a stress response emanating from excessive uptake of dietary Cu and cellular toxicity.

  15. Energetic endpoints provide early indicators of life history effects in a freshwater gastropod exposed to the fungicide, pyraclostrobin.

    Science.gov (United States)

    Fidder, Bridgette N; Reátegui-Zirena, Evelyn G; Olson, Adric D; Salice, Christopher J

    2016-04-01

    Organismal energetics provide important insights into the effects of environmental toxicants. We aimed to determine the effects of pyraclostrobin on Lymnaea stagnalis by examining energy allocation patterns and life history traits. Juvenile snails exposed to pyraclostrobin decreased feeding rate and increased apparent avoidance behaviors at environmentally relevant concentrations. In adults, we found that sublethal concentrations of pyraclostrobin did not affect reproductive output, however, there were significant effects on developmental endpoints with longer time to hatch and decreased hatching success in pyraclostrobin-exposed egg masses. Further, there were apparent differences in developmental effects depending on whether mothers were also exposed to pyraclostrobin suggesting this chemical can exert intergenerational effects. Pyraclostrobin also affected protein and carbohydrate content of eggs in mothers that were exposed to pyraclostrobin. Significant effects on macronutrient content of eggs occurred at lower concentrations than effects on gross endpoints such as hatching success and time to hatch suggesting potential value for these endpoints as early indicators of ecologically relevant stress. These results provide important insight into the effects of a common fungicide on important endpoints for organismal energetics and life history. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Mercury remediation in wetland sediment using zero-valent iron and granular activated carbon

    Science.gov (United States)

    Lewis, Ariel S.; Huntington, Thomas G.; Marvin-DiPasquale, Mark C.; Amirbahman, Aria

    2016-01-01

    Wetlands are hotspots for production of toxic methylmercury (MeHg) that can bioaccumulate in the food web. The objective of this study was to determine whether the application of zero-valent iron (ZVI) or granular activated carbon (GAC) to wetland sediment could reduce MeHg production and bioavailability to benthic organisms. Field mesocosms were installed in a wetland fringing Hodgdon Pond (Maine, USA), and ZVI and GAC were applied. Pore-water MeHg concentrations were lower in treated compared with untreated mesocosms; however, sediment MeHg, as well as total Hg (THg), concentrations were not significantly different between treated and untreated mesocosms, suggesting that smaller pore-water MeHg concentrations in treated sediment were likely due to adsorption to ZVI and GAC, rather than inhibition of MeHg production. In laboratory experiments with intact vegetated sediment clumps, amendments did not significantly change sediment THg and MeHg concentrations; however, the mean pore-water MeHg and MeHg:THg ratios were lower in the amended sediment than the control. In the laboratory microcosms, snails (Lymnaea stagnalis) accumulated less MeHg in sediment treated with ZVI or GAC. The study results suggest that both GAC and ZVI have potential for reducing MeHg bioaccumulation in wetland sediment.

  17. Evaluation of processed borax as antidote for aconite poisoning.

    Science.gov (United States)

    Sarkar, Prasanta Kumar; Prajapati, Pradeep K; Shukla, Vinay J; Ravishankar, Basavaiah

    2017-06-09

    Aconite root is very poisonous; causes cardiac arrhythmias, ventricular fibrillation and ventricular tachycardia. There is no specific antidote for aconite poisoning. In Ayurveda, dehydrated borax is mentioned for management of aconite poisoning. The investigation evaluated antidotal effect of processed borax against acute and sub-acute toxicity, cardiac toxicity and neuro-muscular toxicity caused by raw aconite. For acute protection Study, single dose of toxicant (35mg/kg) and test drug (22.5mg/kg and 112.5mg/kg) was administered orally, and then 24h survival of animals was observed. The schedule was continued for 30 days in sub-acute protection Study with daily doses of toxicant (6.25mg/kg), test drug (22.5mg/kg and 112.5mg/kg) and vehicle. Hematological and biochemical tests of blood and serum, histopathology of vital organs were carried out. The cardiac activity Study was continued for 30 days with daily doses of toxicant (6.25mg/kg), test drug (22.5mg/kg), processed borax solution (22.5mg/kg) and vehicle; ECG was taken after 1h of drug administration on 1 TB , 15th and on 30th day. For neuro-muscular activity Study, the leech dorsal muscle response to 2.5µg of acetylcholine followed by response of toxicant at 25µg and 50µg doses and then response of test drug at 25µg dose were recorded. Protection index indicates that treated borax gave protection to 50% rats exposed to the lethal dose of toxicant in acute protection Study. Most of the changes in hematological, biochemical parameters and histopathological Study induced by the toxicant in sub-acute protection Study were reversed significantly by the test drug treatment. The ventricular premature beat and ventricular tachyarrhythmia caused by the toxicant were reversed by the test drug indicate reversal of toxicant induced cardio-toxicity. The acetylcholine induced contractions in leech muscle were inhibited by toxicant and it was reversed by test drug treatment. The processed borax solution is found as an

  18. Disintegrins from Hematophagous Sources

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    Ivo M. B. Francischetti

    2012-04-01

    Full Text Available Bloodsucking arthropods are a rich source of salivary molecules (sialogenins which inhibit platelet aggregation, neutrophil function and angiogenesis. Here we review the literature on salivary disintegrins and their targets. Disintegrins were first discovered in snake venoms, and were instrumental in our understanding of integrin function and also for the development of anti-thrombotic drugs. In hematophagous animals, most disintegrins described so far have been discovered in the salivary gland of ticks and leeches. A limited number have also been found in hookworms and horseflies, and none identified in mosquitoes or sand flies. The vast majority of salivary disintegrins reported display a RGD motif and were described as platelet aggregation inhibitors, and few others as negative modulator of neutrophil or endothelial cell functions. This notably low number of reported disintegrins is certainly an underestimation of the actual complexity of this family of proteins in hematophagous secretions. Therefore an algorithm was created in order to identify the tripeptide motifs RGD, KGD, VGD, MLD, KTS, RTS, WGD, or RED (flanked by cysteines in sialogenins deposited in GenBank database. The search included sequences from various blood-sucking animals such as ticks (e.g., Ixodes sp., Argas sp., Rhipicephalus sp., Amblyomma sp., tabanids (e.g., Tabanus sp., bugs (e.g., Triatoma sp., Rhodnius prolixus, mosquitoes (e.g., Anopheles sp., Aedes sp., Culex sp., sand flies (e.g., Lutzomyia sp., Phlebotomus sp., leeches (e.g., Macrobdella sp., Placobdella sp. and worms (e.g., Ancylostoma sp.. This approach allowed the identification of a remarkably high number of novel putative sialogenins with tripeptide motifs typical of disintegrins (>450 sequences whose biological activity remains to be verified. This database is accessible

  19. Trophic structure of the benthic invertebrate community in the littoral zone of a mountain cascade system

    Directory of Open Access Journals (Sweden)

    M. Prus

    2002-02-01

    Full Text Available The cascade of Solina/Myczkowce dam reservoirs situated in the West Carpathian Mts was investigated. The cascade consists of two reservoirs, the upper one built 35 yr ago on the San and Solinka Rivers of 2100 ha area separated from another one, of 190 ha area, with hypolimnion cold water supplied from the upper one.

    The offshore zone was investigated monthly (6 sites of upper, 3 sites of lower reservoir using a tube bottom sampler. Besides numbers, biomass and biodiversity indices, the proportion of predators, plant/detritus-feeders and filter-feeders was assessed.

    In upper reservoir Solina, with a lack of filter-feeders, a clear preponderance of plant-detritus feeders was observed. Predators, consisting mostly of leeches and hydranchnellids were present. In lower reservoir Myczkowce, all three trophic classes were present in the first year of study in almost equal proportions and in 1998 with slight preponderance of plant/detritus feeders was observed.

    The Oligochaeta/Chironomidae index in both reservoirs was low, indicating low degree of eutrophication. Only one site in Solina reservoir (near a fish culture and one in Myczkowce (influenced by tourist activity showed a high value of this index.

  20. An optically stabilized fast-switching light emitting diode as a light source for functional neuroimaging.

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    Daniel A Wagenaar

    Full Text Available Neuroscience research increasingly relies on optical methods for evoking neuronal activity as well as for measuring it, making bright and stable light sources critical building blocks of modern experimental setups. This paper presents a method to control the brightness of a high-power light emitting diode (LED light source to an unprecedented level of stability. By continuously monitoring the actual light output of the LED with a photodiode and feeding the result back to the LED's driver by way of a proportional-integral controller, drift was reduced to as little as 0.007% per hour over a 12-h period, and short-term fluctuations to 0.005% root-mean-square over 10 seconds. The LED can be switched on and off completely within 100 μs, a feature that is crucial when visual stimuli and light for optical recording need to be interleaved to obtain artifact-free recordings. The utility of the system is demonstrated by recording visual responses in the central nervous system of the medicinal leech Hirudo verbana using voltage-sensitive dyes.

  1. The cases of observance and violation of politeness maxims by communicants in the ego-state of natural Child

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    Гульнара Фанзиловна Гизатова

    2014-12-01

    Full Text Available Nowadays, the study of human communication is of great importance in linguistics and psychology. In order to achieve smooth and conflict-free interaction it is necessary not only to respect the rules of politeness, but also to take into account the position of the speaker and the addressee. This explains the need to study many psychological factors in communication. This paper studies the ego-state of Natural Child in speech communication. Investigating the behavior of communicants in the ego-state of Natural Child, we rely on the theory of transactional analysis (E. Bern 1961 . According to this theory, the behavior of the speaker and the addressee in the ego-states of Natural Child varies from curious, inspiring, dreamy, and natural to the selfish, spiteful, shameless and impatient. The material for investigation is the dialogs from British and American fiction of XIX-XXI centuries. The dialogs contain the speaker and addressee’s replicas, meeting the essential requirements of the Principle of Politeness (G. Leech 1983 and the theory of transactional analysis. In our work we have applied hypothetical-deductive method, and methods of definitional and contextual analysis. The anylisis of our material demonstrates that communicants in the ego-state of Natural Child observe the maxims of generosity, tact and agreement, and violate the maxims of approbation, modesty and tact. Thus, the implementation of politeness maxims by communicants in ego-state of Natural Child depends entirely on their behavior.

  2. Development of Hepatozoon caimani (Carini, 1909 Pessôa, De Biasi & De Souza, 1972 in the Caiman Caiman c. crocodilus, the frog Rana catesbeiana and the mosquito Culex fatigans

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    Lainson Ralph

    2003-01-01

    Full Text Available The sporogony of Hepatozoon caimani has been studied, by light microscopy, in the mosquito Culex fatigans fed on specimens of the caiman Caiman c. crocodilus showing gametocytes in their peripheral blood. Sporonts iniciate development in the space between the epithelium of the insect gut and the elastic membrane covering the haemocoele surface of the stomach. Sporulating oocysts are clustered on the gut, still invested by the gut surface membrane. Fully mature oocysts were first seen 21 days after the blood-meal. No sporogonic stages were found in some unidentified leeches fed on an infected caiman, up to 30 days following the blood-meal. When mosquitoes containing mature oocysts were fed to frogs (Leptodactylus fuscus and Rana catesbeiana, cysts containing cystozoites developed in the internal organs, principally the liver. Feeding these frogs to farm-bred caimans resulted in the appearance of gametocytes in their peripheral blood at some time between 59 and 79 days later, and the development of tissue cysts in the liver, spleen, lungs and kidneys. Transmission of the parasite was also obtained by feeding young caimans with infected mosquitoes and it is suggested that both methods occur in nature. The finding of similar cysts containing cystozoites in the semi-aquatic lizard Neusticurus bicarinatus, experimentally fed with infected C. fatigans, suggests that other secondary hosts may be involved.

  3. A preliminary disease survey in the wild Nile crocodile (Crocodylus niloticus population in the Okavango Delta, Botswana

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    A. J. Leslie

    2011-04-01

    Full Text Available The objective of this study was to conduct a preliminary survey of diseases that might be present in the wild Nile crocodile population in the Okavango Delta, Botswana. Blood samples were collected from crocodiles ranging in size from 34.0cmto 463.0cmtotal length. Samples were examined for blood parasites and underwent a haematological analysis. Before release the crocodiles were examined for various clinical abnormalities. Of the 144 crocodiles examined, none were visibly sick or displayed any signs of disease. No antibodies to Mycoplasma crocodyli were detected. Hepatozoon pettiti was present in 55.3 % of blood smears examined, but there was no significant difference in any of the haematological values between the infected and uninfected crocodiles, and a high prevalence of Hepatozoon infection is not uncommon in other species. Only 7.6 % of the examined crocodiles were infested with leeches. Further research is required for several of the crocodilian diseases, in particular to elucidate the role of wild crocodilians as reservoirs of infection.

  4. Conformal field theory, triality and the Monster group

    International Nuclear Information System (INIS)

    Dolan, L.; Goddard, P.; Montague, P.

    1990-01-01

    From an even self-dual N-dimensional lattice, Λ, it is always possible to construct two (chiral) conformal field theories, an untwisted theory H (Λ), and a Z 2 -twisted theory H (Λ), constructed using the reflection twist. (N must be a multiple of 8 and the theories are modular invariant if it is a multiple of 24.) Similarly, from a doubly-even self-dual binary code C, it is possible to construct two even self-dual lattices, an untwisted one Λ C and a twisted one anti Λ C . It is shown that H(Λ C ) always has a triality structure, and that this triality induces first an isomorphism H(anti Λ C )≅H(Λ C ) and, through this, a triality of H(anti Λ C ). In the case where C is the Golay code, anti Λ C is the Leech lattice and the induced triality is the extra symmetry necessary to generate the Monster group from (an extension of) Conway's group. Thus it is demonstrated that triality is a generic symmetry. The induced isomorphism accounts for all 9 of the coincidences between the 48 conformal field theories H(Λ) and H(Λ) with N=24. (orig.)

  5. Mechanisms underlying rhythmic locomotion: body–fluid interaction in undulatory swimming

    Science.gov (United States)

    Chen, J.; Friesen, W. O.; Iwasaki, T.

    2011-01-01

    Swimming of fish and other animals results from interactions of rhythmic body movements with the surrounding fluid. This paper develops a model for the body–fluid interaction in undulatory swimming of leeches, where the body is represented by a chain of rigid links and the hydrodynamic force model is based on resistive and reactive force theories. The drag and added-mass coefficients for the fluid force model were determined from experimental data of kinematic variables during intact swimming, measured through video recording and image processing. Parameter optimizations to minimize errors in simulated model behaviors revealed that the resistive force is dominant, and a simple static function of relative velocity captures the essence of hydrodynamic forces acting on the body. The model thus developed, together with the experimental kinematic data, allows us to investigate temporal and spatial (along the body) distributions of muscle actuation, body curvature, hydrodynamic thrust and drag, muscle power supply and energy dissipation into the fluid. We have found that: (1) thrust is generated continuously along the body with increasing magnitude toward the tail, (2) drag is nearly constant along the body, (3) muscle actuation waves travel two or three times faster than the body curvature waves and (4) energy for swimming is supplied primarily by the mid-body muscles, transmitted through the body in the form of elastic energy, and dissipated into the water near the tail. PMID:21270304

  6. ‘Schamoteren met de grote woorden’

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    Wendy Lemmens

    2016-02-01

    Full Text Available ‘Juggling with big words’: Register variation in Hugo Claus’s De verwondering (1962 The prose of Hugo Claus has been the subject of broad scholarly interest, regarding – amongst other things – intertextuality and allegories. The presence of various, contrasting language registers has been briefly touched upon, but has – mainly because of the lack of an appropriate research method – never been studied in greater detail. This preliminary article analyses some excerpts of De verwondering (1962, the first novel in which Claus experiments with register variation, based on the stylistic methodology developed by Leech and Short (2007. The analyses demonstrate that this methodology is highly applicable to analyse not just ‘the style’ of a text, but also to ‘zoom in’ on various registers. In doing so, numerous aspects that help constitute (but at the same time undermine a certain interpretation come more profoundly to the fore, showing that the study of register variation is promising, especially regarding novels in which different varieties of the same language appear.

  7. Sample limited characterization of a novel disulfide-rich venom peptide toxin from terebrid marine snail Terebra variegata.

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    Prachi Anand

    Full Text Available Disulfide-rich peptide toxins found in the secretions of venomous organisms such as snakes, spiders, scorpions, leeches, and marine snails are highly efficient and effective tools for novel therapeutic drug development. Venom peptide toxins have been used extensively to characterize ion channels in the nervous system and platelet aggregation in haemostatic systems. A significant hurdle in characterizing disulfide-rich peptide toxins from venomous animals is obtaining significant quantities needed for sequence and structural analyses. Presented here is a strategy for the structural characterization of venom peptide toxins from sample limited (4 ng specimens via direct mass spectrometry sequencing, chemical synthesis and NMR structure elucidation. Using this integrated approach, venom peptide Tv1 from Terebra variegata was discovered. Tv1 displays a unique fold not witnessed in prior snail neuropeptides. The novel structural features found for Tv1 suggest that the terebrid pool of peptide toxins may target different neuronal agents with varying specificities compared to previously characterized snail neuropeptides.

  8. Bioinspired Non-iridescent Structural Color from Polymer Blend Thin Films

    Science.gov (United States)

    Nallapaneni, Asritha; Shawkey, Matthew; Karim, Alamgir

    Colors exhibited in biological species are either due to natural pigments, sub-micron structural variation or both. Structural colors thus exhibited can be iridescent (ID) or non-iridescent (NID) in nature. NID colors originate due to interference and coherent scattering of light with quasi-ordered micro- and nano- structures. Specifically, in Eastern Bluebird (Sialia sialis) these nanostructures develop as a result of phase separation of β-keratin from cytoplasm present in cells. We replicate these structures via spinodal blend phase separation of PS-PMMA thin films. Colors of films vary from ultraviolet to blue. Scattering of UV-visible light from selectively leeched phase separated blends are studied in terms of varying domain spacing (200nm to 2 μm) of film. We control these parameters by tuning annealing time and temperature. Angle-resolved spectroscopy studies suggest that the films are weakly iridescent and scattering from phase-separated films is more diffused when compared to well-mixed films. This study offers solutions to several color-based application in paints and coatings industry.

  9. A Corpus-based Study on the Use of Contractions by EFL Learners in Argumentative Essays

    Directory of Open Access Journals (Sweden)

    M. Pınar Babanoğlu

    2017-01-01

    Full Text Available Contraction forms in English are mostly occur in speech and informal writing and they are generally avoided in formal writing types such as academic prose, business reports and journal articles, therefore, most teachers discourage their use in academic essays (Biber, Johansonn, Leech, Conrad and Finegan 1999. Contractions in English have two types; negative contractions (isn’t, haven’t, doesn’t and verb contractions (I’m, they’ve, that’s. This corpus based study attempts to investigate contraction usage in learner and native English speaker essays. Major goal is to examine whether learners consider essay writing rules in respect of contractions which are accepted inappropriate for academic prose style. Five corpora, three learner and two native English, were utilized in order to analyze verb and not-contraction forms. Frequency calculations of contraction forms in each corpus compared via log-likelihood measurement for statistical significance.  Results revealed that learners use considerably more contraction forms, especially negative ones, than native English students in their argumentative essays.

  10. Pediatric medical device development by surgeons via capstone engineering design programs.

    Science.gov (United States)

    Sack, Bryan S; Elizondo, Rodolfo A; Huang, Gene O; Janzen, Nicolette; Espinoza, Jimmy; Sanz-Cortes, Magdalena; Dietrich, Jennifer E; Hakim, Julie; Richardson, Eric S; Oden, Maria; Hanks, John; Haridas, Balakrishna; Hury, James F; Koh, Chester J

    2018-03-01

    There is a need for pediatric medical devices that accommodate the unique physiology and anatomy of pediatric patients that is increasingly receiving more attention. However, there is limited literature on the programs within children's hospitals and academia that can support pediatric device development. We describe our experience with pediatric device design utilizing collaborations between a children's hospital and two engineering schools. Utilizing the academic year as a timeline, unmet pediatric device needs were identified by surgical faculty and matched with an engineering mentor and a team of students within the Capstone Engineering Design programs at two universities. The final prototypes were showcased at the end of the academic year and if appropriate, provisional patent applications were filed. All twelve teams successfully developed device prototypes, and five teams obtained provisional patents. The prototypes that obtained provisional patents included a non-operative ureteral stent removal system, an evacuation device for small kidney stone fragments, a mechanical leech, an anchoring system of the chorio-amniotic membranes during fetal surgery, and a fetal oxygenation monitor during fetoscopic procedures. Capstone Engineering Design programs in partnership with surgical faculty at children's hospitals can play an effective role in the prototype development of novel pediatric medical devices. N/A - No clinical subjects or human testing was performed. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Evaluation of molluscicidal activity of three mangrove species (Avicennia schaueriana, Laguncularia racemosa and Rhizophora mangle) and their effects on the bioactivity of Biomphalaria glabrata Say, 1818

    Science.gov (United States)

    Mendes, Renato Juvino de Aragão; Pereira, Adalberto Alves; Nogueira, Aline de Jesus Lustosa; Araújo, Karla Regina Freitas; França, Clícia Rosane Costa; de Carvalho, Iramar Borba; da Silva, Natale Maria Lindoso; Azevedo, Alexandre Santana; Rosa, Ivone Garros

    2018-01-01

    ABSTRACT Schistosomiasis is a disease of global extent reaching populations in social vulnerability. One of the control measures of this parasitosis is the use of molluscicidal substances that can fight snails of the genus Biomphalaria, intermediate hosts of Schistosoma mansoni. The aim of this work was to study the toxic activity of three mangrove species (Avicennia schaueriana Stapf. & Leech, ex Moldenke, 1939, Laguncularia racemosa (L.) CF Gaertn, 1807 and Rhizophora mangle L. 1753) on the biological activities of snails Biomphalaria glabrata. Hydroalcoholic extracts were prepared from the stem and leaves of each of the three plant species to which mollusks were exposed. The phytochemical analysis of plants showed the presence of important metabolites in the leaves and stems of L. racemosa and R. mangle, such as tannins and saponins, but the absence of these metabolites in A. schaueriana. Leaf and stem extracts of the three plant species showed low molluscicidal activity, not reaching the standards determined by the World Health Organization (WHO, 1983). L. racemosa and R. mangle has interfered with motility, feeding and oviposition of snails, unlike the extracts of A. schaueriana, which had no effect on these activities. PMID:29451595

  12. Optimization of methodology for the assessing of bioaccumulation factors of periphyton metals applying the X-ray fluorescence technique

    International Nuclear Information System (INIS)

    Merced Ch, D.

    2015-01-01

    The Lerma River is one of the most polluted at Mexico, has a high pollutant load and low biodiversity, this aquatic plants and species zoo perifiton presented adaptations to environmental conditions that exist due to dumping of wastewater are developed. In this paper bioaccumulation factors (BAF) of Cr, Mn, Fe, Ni, Cu, Zn and Pb metal on Hydrocotyle ranunculoides zoo perifiton associated with the upper reaches of the Lerma River applying the technique of fluorescence X-rays were evaluated in the form of Total Reflection. The BAF were higher compared to the soluble fraction to the total fraction this because the metal in the soluble phase are in solution and are therefore more available to join aquatic organisms, moreover respect to the BAF sediment were ≤ 1.5 indicate that these organisms have little affinity for incorporating metals from the sediment. Considering the sum of the FBA of all metals in each agency notes that the leech was the biggest bio accumulated metals (42468) followed by the worm to (27958), the arthropod with (10757) and finally the snail with (8421). Overall for this study agencies according to the BAF reported to bio accumulate metals are the following behavior Fe > Zn > Cu > Cr > Ni > Mn > Pb. (Author)

  13. The toxicogenomic multiverse: convergent recruitment of proteins into animal venoms.

    Science.gov (United States)

    Fry, Bryan G; Roelants, Kim; Champagne, Donald E; Scheib, Holger; Tyndall, Joel D A; King, Glenn F; Nevalainen, Timo J; Norman, Janette A; Lewis, Richard J; Norton, Raymond S; Renjifo, Camila; de la Vega, Ricardo C Rodríguez

    2009-01-01

    Throughout evolution, numerous proteins have been convergently recruited into the venoms of various animals, including centipedes, cephalopods, cone snails, fish, insects (several independent venom systems), platypus, scorpions, shrews, spiders, toxicoferan reptiles (lizards and snakes), and sea anemones. The protein scaffolds utilized convergently have included AVIT/colipase/prokineticin, CAP, chitinase, cystatin, defensins, hyaluronidase, Kunitz, lectin, lipocalin, natriuretic peptide, peptidase S1, phospholipase A(2), sphingomyelinase D, and SPRY. Many of these same venom protein types have also been convergently recruited for use in the hematophagous gland secretions of invertebrates (e.g., fleas, leeches, kissing bugs, mosquitoes, and ticks) and vertebrates (e.g., vampire bats). Here, we discuss a number of overarching structural, functional, and evolutionary generalities of the protein families from which these toxins have been frequently recruited and propose a revised and expanded working definition for venom. Given the large number of striking similarities between the protein compositions of conventional venoms and hematophagous secretions, we argue that the latter should also fall under the same definition.

  14. iDNA screening: Disease vectors as vertebrate samplers.

    Science.gov (United States)

    Kocher, Arthur; de Thoisy, Benoit; Catzeflis, François; Valière, Sophie; Bañuls, Anne-Laure; Murienne, Jérôme

    2017-11-01

    In the current context of global change and human-induced biodiversity decline, there is an urgent need for developing sampling approaches able to accurately describe the state of biodiversity. Traditional surveys of vertebrate fauna involve time-consuming and skill-demanding field methods. Recently, the use of DNA derived from invertebrate parasites (leeches and blowflies) was suggested as a new tool for vertebrate diversity assessment. Bloodmeal analyses of arthropod disease vectors have long been performed to describe their feeding behaviour, for epidemiological purposes. On the other hand, this existing expertise has not yet been applied to investigate vertebrate fauna per se. Here, we evaluate the usefulness of hematophagous dipterans as vertebrate samplers. Blood-fed sand flies and mosquitoes were collected in Amazonian forest sites and analysed using high-throughput sequencing of short mitochondrial markers. Bloodmeal identifications highlighted contrasting ecological features and feeding behaviour among dipteran species, which allowed unveiling arboreal and terrestrial mammals of various body size, as well as birds, lizards and amphibians. Additionally, lower vertebrate diversity was found in sites undergoing higher levels of human-induced perturbation. These results suggest that, in addition to providing precious information on disease vector host use, dipteran bloodmeal analyses may represent a useful tool in the study of vertebrate communities. Although further effort is required to validate the approach and consider its application to large-scale studies, this first work opens up promising perspectives for biodiversity monitoring and eco-epidemiology. © 2017 John Wiley & Sons Ltd.

  15. Anuran trypanosomes: phylogenetic evidence for new clades in Brazil.

    Science.gov (United States)

    da S Ferreira, Juliana I G; da Costa, Andrea P; Ramirez, Diego; Roldan, Jairo A M; Saraiva, Danilo; da S Founier, Gislene F R; Sue, Ana; Zambelli, Erick R; Minervino, Antonio H H; Verdade, Vanessa K; Gennari, Solange M; Marcili, Arlei

    2015-05-01

    Trypanosomes of anurans and fish are grouped into the Aquatic Clade which includes species isolated from fish, amphibians, turtles and platypus, usually transmitted by leeches and phlebotomine sand flies. Trypanosomes from Brazilian frogs are grouped within the Aquatic Clade with other anuran trypanosome species, where there seems to be coevolutionary patterns with vertebrate hosts and association to Brazilian biomes (Atlantic Forest, Pantanal and Amazonia Rainforest). We characterised the anuran trypanosomes from two different areas of the Cerrado biome and examined their phylogenetic relationships based on the SSU rRNA gene. A total of 112 anurans of six species was analysed and trypanosome prevalence evaluated through haemoculture was found to be 7% (8 positive frogs). However, only three isolates (2.7%) from two anuran species were recovered and cryopreserved. Analysis including SSU rDNA sequences from previous studies segregated the anuran trypanosomes into six groups, the previously reported An01 to An04, and An05 and An06 reported herein. Clade An05 comprises the isolates from Leptodactylus latrans (Steffen) and Pristimantis sp. captured in the Cerrado biome and Trypanosoma chattoni Mathis & Leger, 1911. The inclusion of new isolates in the phylogenetic analyses provided evidence for a new group (An06) of parasites from phlebotomine hosts. Our results indicate that the diversity of trypanosome species is underestimated since studies conducted in Brazil and other regions of the world are still few.

  16. Chronic Lead Intoxication From Eating Wild-Harvested Game.

    Science.gov (United States)

    Buenz, Eric J; Parry, Gareth J

    2018-05-01

    The purpose of this article is to determine if conversion from eating wild game harvested with lead-based ammunition to nonlead-based ammunition results in lower blood lead levels. Supersonic injection of toxin-leeching frangible projectiles into food is intuitively bad. As much as 95% of the ~13.7 million hunters in the United States choose shrapnel-inducing lead bullets to kill game; in addition, not harvesting meat is an incarcerable crime. A lead ammunition ban on certain federal lands was recently rescinded and the National Rifle Association refutes any risk from eating lead bullet-harvested game. A patient subsisting solely on lead-shot meat was converted to non-lead ammunition and his blood lead level tracked. Concomitant with his conversion to nonlead ammunition, a controlled experiment was performed using the patient's bullets to determine his daily lead intake from lead-shot meat. While eating lead-shot meat, the patient was consuming 259.3 ± 235.6 µg of lead daily and his blood lead level was 74.7 µg/dL. Conversion to nonlead ammunition was associated with a reduced blood lead level. Unsafe blood lead levels can occur from eating game harvested with lead ammunition. Physicians should warn hunting patients of this potential risk and counsel them about the availability of nonlead ammunition alternatives. Copyright © 2018 Elsevier Inc. All rights reserved.

  17. The survival of monogenean (platyhelminth) parasites on fish skin.

    Science.gov (United States)

    Kearn, G C

    1999-01-01

    This review deals with the problems faced by those monogenean (platyhelminth) parasites that attach themselves to fish skin. The structure of the skin and the ways in which the posterior hook-bearing haptor achieves virtually permanent attachment to the skin are considered. Small marginal hooklets are specialized for attachment to superficial host epidermal cells, finding anchorage in the terminal web of keratinous tonofilaments, while large hooks (hamuli) may penetrate into and lodge in the collagenous dermis. The complementary roles of suction and sticky secretions in haptor attachment and the role of the pharynx in temporary attachment during feeding are also considered. During leech-like locomotion the haptor is briefly detached and, at this critical time, the anterior end is strongly fixed to the wet, current-swept and possibly slimy skin by a sticky secretion. This secretion is deployed on paired pads or discs, the latter sometimes backed up by suction. After attachment by the haptor is re-established, the special tegument covering the anterior adhesive areas may be instrumental in their instant release. The role of fish skin in the phenomenon of host specificity and in the generation of a defensive response against monogeneans is considered and site-specificity of parasites on the host's body is discussed. Possible selection pressures exerted by predatory 'cleaner' organisms are briefly evaluated.

  18. Distribution and ecology of Dreissena polymorpha (pallas) and Dreissena bugensis (andrusov) in the upper Volga basin

    Science.gov (United States)

    Shcherbina, G. Kh; Buckler, D.R.

    2006-01-01

    This paper presents data on contemporary distribution patterns of two species of Dreissenidae, the zebra mussel (Dreissena polymorpha) and the Quagga mussel (Dreissena bugensis), and their role in ecosystem processes in the Ivan'kovo, Uglich, Rybinsk, and Gorky Reservoirs of the Upper Volga River basin. The role of zebra mussel was also studied in experimental mesocosms of 15 m3. Maximum abundance and species diversity of macroinvertebrates, especially of leeches, polychaetes, crustaceans, and heterotopic insects, were attained in the portions of reservoirs where Dreissenidae were present and in experimental mesocosms where zebra mussel biomass was the highest. In the mesocosm studies, the presence of zebra mussel druses (colonies) provided shelter for macroinvertebrates, reducing their vulnerability to predation by perch (Perca fluviatills) larvae and yearlings, thereby increasing macroinvertebrate species diversity. It was shown that in addition to its role in aquatic biocenosis (ecological community) formation and water purification, Dreissenidae are important food objects for benthophagous fishes, especially roach (Rutilus rutilus). Examination of intestines of benthophagous fishes showed that the length of Dreissenidae ranged from 5 to 20 mm in roach; from 4 to 14 mm in silver bream (Blicca bjoerkna), and from 2 to 10 mm in bream (Abramis brama). The largest mussels consumed were Quagga mussels up to 30 mm, noted in the predatory cyprinid, ide (Leuciscus idus). Copyright ?? 2006 by ASTM International.

  19. Direct Open Venous Drainage: An Alternative Choice for Flap Congestion Salvage.

    Science.gov (United States)

    Park, Su Han; Choi, Woo Young; Son, Kyung Min; Cheon, Ji Seon; Yang, Jeong Yeol

    2015-12-01

    In this report, we present a scalp defect reconstruction with lateral arm free flap. We highlight the difficulty in obtaining a recipient vein and the venous drainage managed through an open end of the donor vein. A 52-year-old woman presented with a pressure sore on the left scalp. A lateral arm free flap was transferred to cover this 8×6 cm defect. The arterial anastomosis was successful, but no recipient vein could be identified within the wound bed. Instead, we used a donor venous end for the direct open venous drainage. In order to keep this exposed venous end patent, we applied heparin-soaked gauze dressing to the wound. Also, the vein end was mechanically dilated and irrigated with heparin solution at two hour intervals. Along with fluid management and blood transfusion, this management was continued for the five days after the operation. The flap survived well without any complication. Through this case, we were able to demonstrate that venous congestion can be avoided by drainage of the venous blood through an open vessel without the use of leeches.

  20. The Devils Mountain Fault zone: An active Cascadia upper plate zone of deformation, Pacific Northwest of North America

    Science.gov (United States)

    Barrie, J. Vaughn; Greene, H. Gary

    2018-02-01

    The Devils Mountain Fault Zone (DMFZ) extends east to west from Washington State to just south of Victoria, British Columbia, in the northern Strait of Juan de Fuca of Canada and the USA. Recently collected geophysical data were used to map this fault zone in detail, which show the main fault trace, and associated primary and secondary (conjugate) strands, and extensive northeast-southwest oriented folding that occurs within a 6 km wide deformation zone. The fault zone has been active in the Holocene as seen in the offset and disrupted upper Quaternary strata, seafloor displacement, and deformation within sediment cores taken close to the seafloor expression of the faults. Data suggest that the present DMFZ and the re-activated Leech River Fault may be part of the same fault system. Based on the length and previously estimated slip rates of the fault zone in Washington State, the DMFZ appears to have the potential of producing a strong earthquake, perhaps as large as magnitude 7.5 or greater, within 2 km of the city of Victoria.

  1. Annelids in evolutionary developmental biology and comparative genomics

    Directory of Open Access Journals (Sweden)

    Mcdougall C.

    2008-09-01

    Full Text Available Annelids have had a long history in comparative embryology and morphology, which has helped to establish them in zoology textbooks as an ideal system to understand the evolution of the typical triploblastic, coelomate, protostome condition. In recent years there has been a relative upsurge in embryological data, particularly with regard to the expression and function of developmental control genes. Polychaetes, as well as other annelids such as the parasitic leech, are now also entering the age of comparative genomics. All of this comparative data has had an important impact on our views of the ancestral conditions at various levels of the animal phylogeny, including the bilaterian ancestor and the nature of the annelid ancestor. Here we review some of the recent advances made in annelid comparative development and genomics, revealing a hitherto unsuspected level of complexity in these ancestors. It is also apparent that the transition to a parasitic lifestyle leads to, or requires, extensive modifications and derivations at both the genomic and embryological levels.

  2. Statistical identification of stimulus-activated network nodes in multi-neuron voltage-sensitive dye optical recordings.

    Science.gov (United States)

    Fathiazar, Elham; Anemuller, Jorn; Kretzberg, Jutta

    2016-08-01

    Voltage-Sensitive Dye (VSD) imaging is an optical imaging method that allows measuring the graded voltage changes of multiple neurons simultaneously. In neuroscience, this method is used to reveal networks of neurons involved in certain tasks. However, the recorded relative dye fluorescence changes are usually low and signals are superimposed by noise and artifacts. Therefore, establishing a reliable method to identify which cells are activated by specific stimulus conditions is the first step to identify functional networks. In this paper, we present a statistical method to identify stimulus-activated network nodes as cells, whose activities during sensory network stimulation differ significantly from the un-stimulated control condition. This method is demonstrated based on voltage-sensitive dye recordings from up to 100 neurons in a ganglion of the medicinal leech responding to tactile skin stimulation. Without relying on any prior physiological knowledge, the network nodes identified by our statistical analysis were found to match well with published cell types involved in tactile stimulus processing and to be consistent across stimulus conditions and preparations.

  3. Arterial and venous revascularization with bifurcation of a single central artery: a reliable strategy for Tamai Zone I replantation.

    Science.gov (United States)

    Hsu, Chung-Chen; Lin, Yu-Te; Moran, Steven L; Lin, Cheng-Hung; Wei, Fu-Chan; Lin, Chih-Hung

    2010-12-01

    Replantation of the distal phalanx and pulp can be performed to improve finger function and finger aesthetics; however, establishing adequate venous drainage is a challenge. Slattery et al. reported microsurgical reattachment of a partial distal phalanx with the use of a bifurcated terminal digital artery. The bifurcation was divided into two pedicles, one of which was used for venous drainage. In this article, the authors report their experience with a similar technique and propose a new algorithm for distal finger replantation. From January of 2008 to February of 2009, five replantations were performed using a single central artery. The replanted levels were pulp, avulsed fingertip of the thumb, and distal phalanges. There was no volar vein, dorsal vein, or second artery available in the amputated part for standard venous drainage. Venous drainage in all cases was established by creating an anastomosis from a branch of the solitary terminal artery to a recipient vein. All digits were replanted successfully without evidence of arterial insufficiency or venous congestion. Partial necrosis was not identified postoperatively in any of the five fingers. There were no cases of wound infection. A branch of the central solitary artery may be used successfully to reestablish venous outflow in cases of distal finger tip replantation. This technique allowed for the salvage of all fingers in this study without the use of leeches or other techniques used in cases of venous insufficiency.

  4. Fingertip replantation at or distal to the nail base: use of the technique of artery-only anastomosis.

    Science.gov (United States)

    Akyürek, M; Safak, T; Keçik, A

    2001-06-01

    The authors describe the functional and aesthetic results of microsurgical replantation of 21 fingertip amputations at or distal to the nail base-namely, zone I amputations. There were 15 male and 6 female patients, with an average age of 26 years (age range, 1-41 years). Replantations were performed using the anastomosis of the artery-only technique, with neither vein nor nerve repair. Venous drainage was provided by an external bleeding method with a fish-mouth incision in "distal" zone I amputations for approximately 7 days, and by the use of leeches in more "proximal" zone I amputations for 10 to 12 days. Results indicated that the overall survival rate was 76%, with 16 of 21 digits surviving. Sensory evaluation at an average follow-up of 12 months (range, 6-18 months) revealed an average static two-point discrimination of 6.1 mm (range, 2.0-8.0 mm). Considering the unfavorable results and the donor site morbidity of various fingertip reconstructions, a microsurgical fingertip replantation should always be considered except in extremely distal, clean-cut, pediatric cases, in which case a composite graft is a possibility. The results of this series indicate that an amputated fingertip in zone I can be salvaged successfully by microvascular anastomosis of the artery only, with a nonmicrosurgical method of venous drainage. Furthermore, acceptable sensory recovery can be expected without any nerve coaptation.

  5. Intramedullary Venous Drainage System for Distal Fingertip Replantations.

    Science.gov (United States)

    Purisa, Husrev; Ozturk, Muhammed Besir; Kabakas, Fatih; Mersa, Berkan; Ozcelik, Ismail Bulent; Sezer, Ilker

    2017-08-01

    The number of venous anastomoses performed during fingertip replantation is one of the most important factors affecting the success of replantation. However, because vessel diameters decrease in the zone 1 level, vessel anastomoses, especially vein anastomoses, are technically difficult and, thus, cannot be performed in most cases. Alternative venous drainage methods are crucial when any reliable vein repair is not possible. In the literature, so many artery-only replantation techniques have been defined, such as arteriovenous anastomoses, forming an arteriovenous or venocutaneous fistula, manual milking and massage, puncturing, and external bleeding via a fishmouth incision and using a medical leech. It has been shown that, in distal fingertip replantations, the medullary cavity may also be a good way for venous return. In this study, we introduce an alternative intramedullary venous drainage system we developed to facilitate venous drainage in artery-only fingertip replantations. The results of 24 fingertip replantations distal to the nail fold by using this system are presented with a literature review.

  6. A Corpus-based Stylistic Analysis of Body-Soul and Heaviness-Lightness Metaphors in Kundera's Novel The Unbearable Lightness of Being

    Directory of Open Access Journals (Sweden)

    Khalid Shakir Hussein

    2015-10-01

    Full Text Available This paper represents an attempt to conduct a corpus-based stylistic analysis of  two conceptual metaphors in The Unbearable Lightness of Being, which is a novel written by Milan Kundera. Soul-body and lightness-heaviness metaphors are foregrounded as being central themes all through the novel. The way such metaphors are used in the novel indicates an insightful employment of metaphor as a cognitive tool which empowers language users with a capacity of conceptualizing different experiences. The researcher adopts conceptual metaphor theory to produce a sort of conceptual analysis incorporating Leech's semantic componential analysis within the overall analytic procedure. Different techniques are figured out in relation to the creative ways of manipulating the cognitive level of language, such as conceptual switching, conceptual extension, and conceptual fusion. These creative techniques are carefully used in the novel under investigation with different ranges of metaphorical creativity. Conceptual switching might be simple but very active in deviating from the conventional conceptual system. Conceptual extension marks certain minute elaborations conventional metaphors undergo extending the limits of cognitive conceptualization. As for conceptual fusion, it proves to be interestingly powerful in producing certain aggregations of metaphorical mappings. Keywords: Conceptual Metaphor Theory, Metaphorical Creativity, Metaphorical Mappings, Corpus Stylistics

  7. [Research progress in hirudin fusion protein--review].

    Science.gov (United States)

    Zhang, Chuan-Ling; Yu, Ai-Ping; Jin, Ji-De; Wu, Chu-Tse

    2007-02-01

    Natural hirudin extracted from the secretion of medical leech salivary gland is a single-chain peptide containing 65 aminoacid residues with molecular weight of 7000 D, and exists in three isomers of HV1, HV2 and HV3. Hirudin possesses three disulfide bridges forming the structure of core cyclic peptides, which binds to the catalytic site of thrombin so as to inhibit the catalysis of thrombin. Its c-terminus rich in acidic aminoacid residues possesses hydrophilicity, and is free on the molecular surface, and can bind with fibrin recognition site of hirudin. The minimal segment of 12 - 16 C-terminal acidic residues keeps the minimal activity of anti-thrombosis. Thus, hirudin, as a potent and specific inhibitor of thrombin, can be used to protect from and to treat clinically thrombosis. As it has some disadvantages such as short half-life, bleeding side-effect and mono-function, and so on, hirudin has been fused with some other functional proteins in recent years. The obtained fusion proteins can prolong the half life of hirudin, or relieve it bleeding side effect, or bring new functions, such as thrombolysis, inhibiting the platelet aggregation, targeting specifically. The research progress in hirudin fusion protein was summarized in this review.

  8. NEGATION AFFIXES IN ENGLISH

    Directory of Open Access Journals (Sweden)

    Dedy Subandowo -

    2017-02-01

    Full Text Available Abstract: This research entitled "Negation Affixes in English". This study is aimed to describe the various negation affixes in English, morphological process, morphophonemic and meaning. The research data were taken from various sources of English grammar book, morphology, research journal and the book which relatees to the research. English grammar books used in this study are written by Otto Jesperson, Marcella Frank, Greenbaum and Geoffrey Leech.  The method used in this research is the descriptive-qualitative method. While the data collection techniques are performed by using jot-down method. And the results of analysis are presented in tabular form and descriptive method. The result of the research shows that English has six types of negative affixes which are categorized by the intensity of its appearance, such as dis-, in-, non-, un-, anti- and -less. Based on the function, negation affixes are divided into several categories such as adjectives, nouns, verbs, and adverbs. The morphophonemic affix in- has four allomorphs, they are in-, im-, il- and ir- . While the analysis revealed that negation affixes have some basic meanings, such as ‘not’, ‘without’, and ‘anti’.

  9. Does α-Amino-β-methylaminopropionic Acid (BMAA Play a Role in Neurodegeneration?

    Directory of Open Access Journals (Sweden)

    Brett A. Neilan

    2011-09-01

    Full Text Available The association of α-amino-β-methylaminopropionic acid (BMAA with elevated incidence of amyotrophic lateral sclerosis/Parkinson’s disease complex (ALS/PDC was first identified on the island of Guam. BMAA has been shown to be produced across the cyanobacterial order and its detection has been reported in a variety of aquatic and terrestrial environments worldwide, suggesting that it is ubiquitous. Various in vivo studies on rats, mice, chicks and monkeys have shown that it can cause neurodegenerative symptoms such as ataxia and convulsions. Zebrafish research has also shown disruption to neural development after BMAA exposure. In vitro studies on mice, rats and leeches have shown that BMAA acts predominantly on motor neurons. Observed increases in the generation of reactive oxygen species (ROS and Ca2+ influx, coupled with disruption to mitochondrial activity and general neuronal death, indicate that the main mode of activity is via excitotoxic mechanisms. The current review pertaining to the neurotoxicity of BMAA clearly demonstrates its ability to adversely affect neural tissues, and implicates it as a potentially significant compound in the aetiology of neurodegenerative disease. When considering the potential adverse health effects upon exposure to this compound, further research to better understand the modes of toxicity of BMAA and the environmental exposure limits is essential.

  10. A Case Study on the Mortality of Cobia (Rachycentron canadum) Cultured in Traditional Cages.

    Science.gov (United States)

    Chu, Kua Beng; Abdulah, Azila; Abdullah, Siti Zahrah; Bakar, Ramley Abu

    2013-12-01

    The mass mortality of cobia (Rachycentron canadum) within 2-3 days was reported by 3 private farms in Bukit Tambun, Pulau Pinang, in February and March 2007. Only cobia with body weights of 3-4 kg were affected. Most diseased cobia swam on the surface and displayed flashing behaviour. All samples were positive for viral nervous necrosis (VNN) with low to medium levels of infection. Infestations by leeches (Zeylanicobdella arugamensis), body monogeneans (Benedenia sp.) and copepods (Caligus sp.) were also found, but no pathogenic bacteria were isolated. All water quality parameters monitored were within optimal ranges for culturing cobia. The main causes of high mortality in cobia remain unclear during the study. However, we believe that the mass mortality of cobia could be probably due to VNN infection and that the rate of mortality will increase further when cobia are subjected to aquaculture-related stresses (e.g., limited space). Traditional cages with a size of 2 (length) × 2 (width) × 1 m (depth) should only be used for rearing cobia below 1 kg in weight given the species' natural behaviours. In addition, cobia fingerlings should be screened for VNN prior to stocking them in cages.

  11. Estradiol coupling to human monocyte nitric oxide release is dependent on intracellular calcium transients: evidence for an estrogen surface receptor.

    Science.gov (United States)

    Stefano, G B; Prevot, V; Beauvillain, J C; Fimiani, C; Welters, I; Cadet, P; Breton, C; Pestel, J; Salzet, M; Bilfinger, T V

    1999-10-01

    We tested the hypothesis that estrogen acutely stimulates constitutive NO synthase (cNOS) activity in human peripheral monocytes by acting on an estrogen surface receptor. NO release was measured in real time with an amperometric probe. 17beta-estradiol exposure to monocytes stimulated NO release within seconds in a concentration-dependent manner, whereas 17alpha-estradiol had no effect. 17beta-estradiol conjugated to BSA (E2-BSA) also stimulated NO release, suggesting mediation by a membrane surface receptor. Tamoxifen, an estrogen receptor inhibitor, antagonized the action of both 17beta-estradiol and E2-BSA, whereas ICI 182,780, a selective inhibitor of the nuclear estrogen receptor, had no effect. We further showed, using a dual emission microfluorometry in a calcium-free medium, that the 17beta-estradiol-stimulated release of monocyte NO was dependent on the initial stimulation of intracellular calcium transients in a tamoxifen-sensitive process. Leeching out the intracellular calcium stores abolished the effect of 17beta-estradiol on NO release. RT-PCR analysis of RNA obtained from the cells revealed a strong estrogen receptor-alpha amplification signal and a weak beta signal. Taken together, a physiological dose of estrogen acutely stimulates NO release from human monocytes via the activation of an estrogen surface receptor that is coupled to increases in intracellular calcium.

  12. On the Pragmatist Translation of the Ads Of Coca-Cola and Pepsi

    Institute of Scientific and Technical Information of China (English)

    覃洁

    2012-01-01

    Advertising language is an important research material of social change, it is picked up conveniently. There is no distortion and glossing over history, it is the most simple and most visual material. For English advertising, it reflects values, aesthetic tastes, lifestyle, cultural traditions in the U.S., Britain and other countries. With their own unique ways of recording social change, English advertising is quietly playing an important role in the social life and the psychology of social culture. As a practical style, the advertising language has its unique characteristics in vocabulary, syntax, rhetoric and other aspects. Leech opened the first systematic study of advertising language. He studied the various features of advertising language from literature perspective. With the emergence of the theories of pragmatics, some Chinese scholars, like Zhao Jing, Huang guowen, also set out to explore the advertising language from different aspects. But few of them devoted themselves to the English advertising of American beverage. This paper sets out to explore the issues from a pragmatics perspective. Based on the characteristics of advertising language of American Coca-Cola and Pepsi, the paper analyzes the inevitable language impact on social functioning and the concept of values between English advertising and the interaction of modem simple life, revealing the failure of English advertising language in cross-cultural exchanges and social pragmatic information.

  13. Life inside a gall: closeness does not favour horizontal transmission of Rickettsia between a gall wasp and its parasitoid.

    Science.gov (United States)

    Gualtieri, Liberata; Nugnes, Francesco; Nappo, Anna G; Gebiola, Marco; Bernardo, Umberto

    2017-07-01

    The incidence of horizontal transmission as a route for spreading symbiont infections is still being debated, but a common view is that horizontal transfers require intimate between-species relationships. Here we study a system that meets ideal requirements for horizontal transmission: the gall wasp Leptocybe invasa and its parasitoid Quadrastichus mendeli (Hymenoptera: Eulophidae). These wasps belong to the same subfamily, spend most of their lives inside the same minute gall and are both infected by Rickettsia, a maternally inherited endosymbiotic bacteria that infects several arthropods, sometimes manipulating their reproduction, like inducing thelytokous parthenogenesis in L. invasa. Despite intimate contact, close phylogenetic relationship and the parasitoid's host specificity, we show that host and parasitoid do not share the same Rickettsia. We provide indirect evidence that Rickettsia infecting Q. mendeli may be inducing thelytokous parthenogenesis, as the symbiont is densely present in the reproductive apparatus and is vertically transmitted. Phylogenetic analyses based on 16S and gltA placed this symbiont in the leech group. The confirmed and presumed parthenogenesis-inducing Rickettsia discovered so far only infect eulophid wasps, and belong to three different groups, suggesting multiple independent evolution of the parthenogenesis inducing phenotype. We also show some degree of cospeciation between Rickettsia and their eulophid hosts. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. Parasitism in Pterois volitans (Scorpaenidae) from coastal waters of Puerto Rico, the Cayman Islands, and the Bahamas.

    Science.gov (United States)

    Ramos-Ascherl, Zullaylee; Williams, Ernest H; Bunkley-Williams, Lucy; Tuttle, Lillian J; Sikkel, Paul C; Hixon, Mark A

    2015-02-01

    Recently, Pterois volitans, a Pacific species of lionfish, invaded the Atlantic Ocean, likely via the aquarium trade. We examined for internal and external parasites 188 individuals from 8 municipalities of Puerto Rico collected during 2009-2012, 91 individuals from Little Cayman, Cayman Islands, collected during the summers of 2010 and 2011, and 47 individuals from Lee Stocking Island, Bahamas, collected during the summer of 2009. In total, 27 parasite taxa were found, including 3 previously reported species from lionfish, the digenean Lecithochirium floridense, the leech Trachelobdella lubrica, and an Excorallana sp. isopod. We also report another 24 previously unreported parasite taxa from lionfish, including digeneans, monogeneans, cestodes, nematodes, isopods, a copepod, and an acanthocephalan. Among these parasites, several were previously unreported at their respective geographic origins: We report 5 new locality records from Puerto Rico, 9 from Cayman Islands, 5 from the Bahamas, 5 from the Caribbean, and 3 from the subtropical western Atlantic region. Three parasites are reported to associate with a fish host for the first time. The parasite faunas of P. volitans among our 3 study sites were quite different; most of the species infecting lionfish were generalists and/or species that infect carnivorous fishes. Although our study did not assess the impact of parasites on the fitness of invasive lionfish, it provides an important early step. Our results provide valuable comparative data for future studies at these and other sites throughout the lionfish's invaded range.

  15. The Role of the Students in the CLIL Classroom A New Perspective to Identify Types of Tasks

    Directory of Open Access Journals (Sweden)

    David González Gándara

    2017-05-01

    Full Text Available A good deal of authors have spotted the crucial factors to get into account in order to classify tasks for their study. Although the role of the student in the task has been studied before, it has not been considered as a key factor in some of the most influential models. I propose a new perspective to describe it. It consists in a combination of the participation of the students in the input of tasks and their participation in the output. A case study has been carried out to address the statistical effects of the factor proposed in two variables: the amount of As-units (Foster, Tonkyn, & Wigglesworth, 2000 in the L2 produced in the classroom, and among them, the amount of initiating moves (Leech & Weisser, 2003. Transcripts of the audio and video recordings taken during eight CLIL Science lessons taught to an intact class of ten students of grades 1 and 2 were analysed. The results showed that the role of the students in the input had a significant effect on the variables measured. The teacher produced more As-units in general and initiating moves in particular, while the students produced less As-units while still producing more initiating moves.

  16. Microsurgeon Hirudo medicinalis as a Natural Bioshuttle for Spontaneous Mass Vaccination against Influenza A Virus

    Directory of Open Access Journals (Sweden)

    Sajjad Khani

    2011-09-01

    Full Text Available Introduction: Recent report on existence of a stem region of hemagglutinin has arisen new hopes for vaccination of influenza A as it consist of a conserve fusion peptide shared across several influenza subtypes and can be targeted by human immune system. Methods: Given that traditional vaccination based on live attenuated viruses often fails to surpass such viral infection, a great deal of attention has been devoted to develop a safe yet efficient system for vaccination influenza A. We believe that a natural bioshuttle can be recruited for spontaneous mass vaccination. Results: Thus, here, we hypothesize that a bioengineered transgenic Hirudo medicinalis can be considered as an alive bioshuttle for in-situ vaccination against influenza A virus. By introducing the designated gene(s encoding the target fragment (i.e., stem region of hemagglutinin, this microsurgeon can act as a rapid microproducer of viral proteins for in-house mass vaccination through imparting the necessary proteins such as those, naturally presented in leech's saliva. Conclusion: This peculiar bioshuttle can be easily exploited as a medical modality choice at home resulting in greater patient compliance.

  17. Relatedness of content and sentence formation in Japanese

    Directory of Open Access Journals (Sweden)

    Andrej Bekeš

    1993-12-01

    Full Text Available Leech (1983: 63-70 distinguishes two kinds of pragmatics, interpersonal prag­ matics and textual pragmatics.  Our article is concerned with textual pragmatics,  spe­ cifically with the textual motivations behind a format such as a sentence in Japanese. Studying spontaneous spoken discourse, Chafe (1980 proposed two units of spoken discourse on the basis of phonetical and intonational criteria, i.e. the "idea unit" and the "intonation sentence". He finds justification for both units in cognitive processes as follows. Idea units, most often verbalized as clauses, are the linguistic expression of cognitive units that Chafe calls "foci of consciousness". A focus of consciousness is a chunk of information small enough to be processed and verbalized in one step. Next, an intonation sentence, consisting usually of several idea units (or sometimes just one is the verbal expression of a larger cognitive unit, the "center of interest", a chunk of information too large to be verbalized in one step. Concerning the center of interest, Chafe puts forward the following hypothesis.

  18. Optimization of methodology for the assessing of bioaccumulation factors of periphyton metals applying the X-ray fluorescence technique; Optimizacion de la metodologia para la evaluacion de los factores de bioacumulacion de metales en perifiton aplicando la tecnica de fluorescencia de rayos X

    Energy Technology Data Exchange (ETDEWEB)

    Merced Ch, D.

    2015-07-01

    The Lerma River is one of the most polluted at Mexico, has a high pollutant load and low biodiversity, this aquatic plants and species zoo perifiton presented adaptations to environmental conditions that exist due to dumping of wastewater are developed. In this paper bioaccumulation factors (BAF) of Cr, Mn, Fe, Ni, Cu, Zn and Pb metal on Hydrocotyle ranunculoides zoo perifiton associated with the upper reaches of the Lerma River applying the technique of fluorescence X-rays were evaluated in the form of Total Reflection. The BAF were higher compared to the soluble fraction to the total fraction this because the metal in the soluble phase are in solution and are therefore more available to join aquatic organisms, moreover respect to the BAF sediment were ≤ 1.5 indicate that these organisms have little affinity for incorporating metals from the sediment. Considering the sum of the FBA of all metals in each agency notes that the leech was the biggest bio accumulated metals (42468) followed by the worm to (27958), the arthropod with (10757) and finally the snail with (8421). Overall for this study agencies according to the BAF reported to bio accumulate metals are the following behavior Fe > Zn > Cu > Cr > Ni > Mn > Pb. (Author)

  19. FIGURATIVE LANGUAGE FOUND IN VICTOR HUGO’S LES MISERABLE NOVEL: A SEMANTICS APPROACH

    Directory of Open Access Journals (Sweden)

    Hotma Hutasoit

    2016-04-01

    Full Text Available Penelitian ini membahas terjadinya bahasa kiasan dalam karya Victor Hugo yang berjudul Les Miserable melalui pendekatan semantik. Tujuan skripsi ini adalah (1 untuk memahami bahasa kiasan perbandingan dan pertentangan yang di temukan dalam novel “Les Miserables” karya Victor Hugo,(2 untuk memahami bahasa kiasan hubungan yang di temukan dalam novel “Les Miserables” karya Victor Hugo, (3 untuk memahami bahasa kiasan perulangan yang di temukan dalam novel “Les Miserables” karya Victor Hugo. Peneliti didukung oleh teori Leech (1981 dalam semantik terutama untuk makna konotasi dan Dancygier dan Sweetser (2014, Keraf (1994 dan Cruse (2006 untuk bahasa kiasan. Metode kualitatif digunakan dalam penelitian ini dan penelitian pustaka sebagai teknik yang digunakan untuk mengumpulkan data. Peneliti mengambil 55 sampel dari bahasa kiasan dari novel. Bahasa kiasan perbandingan dan pertentangan yaitu 3 personifikasi, 6 metafora, 6 simile, 6 hiperbola, 2 litotes, and 5 paradox. Bahasa kiasan hubungan yaitu 1 metonimi, 6 sinekdot, 4 alusi, dan 1elipsis. Bahasa kiasan perulangan yaitu 2 pleonasme, 2 klimaks, 1 anti-klimaks, 6 retorika, dan 4 repetisi.Temuan dari penelitian ini adalah dari 55 sampel dari bahasa kiasan yang ditemukan dalam novel, peneliti menemukan yang paling banyak 28 bahasa kiasan yang terjadi pada majas perbandingan dan pertentangan, diikuti denagn 15 bahasa kiasan yang terjadi pada majas perulangan, dan yang paling sedikit 12 bahasa kiasan yang terjadi pada majas hubungan dari setiap kategori.

  20. In a time of cholera.

    Science.gov (United States)

    Grace, P A

    2014-03-01

    Dr. Nathaniel Alcock in his book A treatise on cholera described 22 cases of cholera that he treated in 1832. Blood-letting, either by leeches or venesection, was an essential part of the treatment. The belief was that reducing the blood volume would relieve stress on the heart and lungs allowing for better function. The receipts of the Townsend Street Cholera Hospital where Dr. Alcock worked show how extensive the practice was. Outside Dublin, local Boards of Health dealt with the cholera epidemic. Various public measures such as street cleaning and removal of patients to temporary hospitals were undertaken and various cures were tried. The overall mortality rate from cholera in Ireland during the epidemic was 38 %, but in some areas much higher. Even as cholera was spreading in the 1830s, a number of doctors were showing that intravenous fluids could dramatically alter the course of the disease. Unfortunately, their work was ignored and blood-letting continued to be a major component of the treatment of cholera for another 55 years.

  1. Pore opening dynamics in the exocytosis of serotonin

    Science.gov (United States)

    Ramirez-Santiago, Guillermo; Cercos, Montserrat G.; Martinez-Valencia, Alejandro; Salinas Hernandez, Israel; Rodríguez-Sosa, Leonardo; de-Miguel, Francisco F.

    2015-03-01

    The current view of the exocytosis of transmitter molecules is that it starts with the formation of a fusion pore that connects the intravesicular and the extracellular spaces, and is completed by the release of the rest of the transmitter contained in the vesicle upon the full fusion and collapse of the vesicle with the plasma membrane. However, under certain circumstances, a rapid closure of the pore before the full vesicle fusion produces only a partial release of the transmitter. Here we show that whole release of the transmitter occurs through fusion pores that remain opened for tens of milliseconds without vesicle collapse. This was demonstrated through amperometric measurements of serotonin release from electrodense vesicles in the axon of leech Retzius neurons and mathematical modelling. By modeling transmitter release with a diffusion equation subjected to boundary conditions that are defined by the experiment, we showed that those pores with a fast half rise time constant remained opened and allowed the full quantum release without vesicle collapse, whereas pores with a slow rise time constant closed rapidly, thus producing partial release. We conclude that a full transmitter release may occur through the fusion pore in the absence of vesicle collapse. This work was founded by a DGAPA-UNAM grants IN200914 and IN118410 CONACYT GRANT 130031, and CONACyT doctoral fellowships.

  2. Analysis of Misunderstanding Caused by Different Interpretations of Speech Act Labels in Tintin and Asterix Comic Series

    Directory of Open Access Journals (Sweden)

    Farah Attamimi

    2011-01-01

    Full Text Available This paper presents analysis of misunderstanding occurred in a conversation which is caused by different interpretation of speech act labels between the speaker and the hearer. Misunderstanding occurred in these comic series causes various emotional effects to the hearer involved in the conversation. The hearer might feel happy, impressed, embarrassed, or even proud of what the speaker conveys through his/ her utterance. It depends on the face wants used and intended between the participants in the conversation. According to Goffman in Brown and Levinson (1987, “face is something that is emotionally invested, and that can be lost, maintained, or enhanced, and must be constantly attended to in interaction” (p. 60. There are two kinds of face wants. The positive purpose is called face saving act, while the negative one is called face threatening act. The data in this paper are taken from Tintin and Asterix comic series. The theories used cover pragmatics area, especially taxonomy of speech act theory (Yule, 1996; Mey, 2001; Leech, 1991 and theory of the notion of face by Erving Goffman (as cited in Yule, 1996; Thomas, 1995. Therefore, this paper will try to convey how the misinterpretation of speech act labels affects the participants in the conversation.

  3. Prevalence and parasitemia of Haemogregarina sp. in Podocnemis expansa (Testudines: Podocnemididae) from the Brazilian Amazon.

    Science.gov (United States)

    Picelli, Amanda Maria; de Carvalho, Aluísio Vasconcelos; Viana, Lúcio André; Malvasio, Adriana

    2015-01-01

    Seventy-five turtles Podocnemis expansa in the Brazilian Amazon were examined for the presence of ectoparasites and hemoparasites. Samplings were performed in three study areas in the state of Tocantins, Brazil. Twenty-five specimens were sampled per study area (a commercial breeding facility, an indigenous subsistence breeding facility and a wild population of the Javaés River). Hemoparasites of the genus Haemogregarina were found in 66% (50/75) of the turtle specimens, and the infections were restricted to the commercial breeding facility and to the wild population of the Javaés River. The mean level of parasitemia was 54/2,000 erythrocytes (2%). There was no correlation between the body condition index of the chelonians and the level of parasitemia, with no significant difference between genders. No leeches were observed during the physical exams in any of the study areas, but the specimens from the commercial breeding facility were in poor physical condition with shell deformities and the presence of a relatively high amount of skin ulcerations, most likely caused by fungi and bacteria. This was the first study to record the occurrence of hemogregarines on a population scale in P. expansa and helps to increase knowledge about hemoparasites in chelonians in Brazil.

  4. Prevalence and parasitemia of Haemogregarina sp. in Podocnemis expansa (Testudines: Podocnemididae from the Brazilian Amazon

    Directory of Open Access Journals (Sweden)

    Amanda Maria Picelli

    Full Text Available Seventy-five turtles Podocnemis expansa in the Brazilian Amazon were examined for the presence of ectoparasites and hemoparasites. Samplings were performed in three study areas in the state of Tocantins, Brazil. Twenty-five specimens were sampled per study area (a commercial breeding facility, an indigenous subsistence breeding facility and a wild population of the Javaés River. Hemoparasites of the genus Haemogregarina were found in 66% (50/75 of the turtle specimens, and the infections were restricted to the commercial breeding facility and to the wild population of the Javaés River. The mean level of parasitemia was 54/2,000 erythrocytes (2%. There was no correlation between the body condition index of the chelonians and the level of parasitemia, with no significant difference between genders. No leeches were observed during the physical exams in any of the study areas, but the specimens from the commercial breeding facility were in poor physical condition with shell deformities and the presence of a relatively high amount of skin ulcerations, most likely caused by fungi and bacteria. This was the first study to record the occurrence of hemogregarines on a population scale in P. expansa and helps to increase knowledge about hemoparasites in chelonians in Brazil.

  5. Ecological and geographical characteristics of algal communities on gastropod shells of the river Uzh

    Directory of Open Access Journals (Sweden)

    N. M. Korniichuk

    2017-07-01

    Full Text Available Freshwater molluscs serve as test objects in the ecological monitoring of the environment, because they are able to extract in indicator quantity from the environment and accumulate in their bodies radionuclides, various macro- and micronutrients, toxic substances of inorganic and organic origin, and so on. The gastropods are a taxonomically diverse, ecologically plastic and rather widespread group of aquatic organisms, whose role in the life of freshwater ecosystems is very important. Molluscs often have various interactions in biogeocenoses that determines their trophic net. As a rule, these interactions occur in the form of ectocommensalism, endocommensalism, supercrescence, predation or parasitism. The latter type of interaction is the subject of many studies, but the epibionts of gastropods and bivalves have practically not been studied and this research is an effort towards filling this gap. Species composition of algal epibionts identifies specific sensitivity to the effects of certain environmental factors and reflects the processes occurring in their ecosystem water bodies. This determines their efficient use for analyzing changes of water bodies as aquatic habitat, particularly in terms of complex anthropogenic pressure on aquatic ecosystems. The aim of the research was to determine the ecological characteristics of algal communities on gastropod shells: Lymnaea stagnalis, L. auricularia and Viviparus viviparus (the Uzh river, Korosten district, Zhytomyr region. Identified microalgae communities were grouped and studied according to such indices as: confinedness to the habitat (substrate, temperature, fluidity and water oxygenating, saprobiological characteristics according to the Pantle-Buck system in the modification of Sladecek and Watanabe, salinity according to Kolbe’s system, pH at Hustedt scale in the interpretation of M. M. Davydova and geographical limitations of the objects of study. Algal fouling on the shells L. stagnalis

  6. Deep mRNA sequencing of the Tritonia diomedea brain transcriptome provides access to gene homologues for neuronal excitability, synaptic transmission and peptidergic signalling.

    Directory of Open Access Journals (Sweden)

    Adriano Senatore

    Full Text Available The sea slug Tritonia diomedea (Mollusca, Gastropoda, Nudibranchia, has a simple and highly accessible nervous system, making it useful for studying neuronal and synaptic mechanisms underlying behavior. Although many important contributions have been made using Tritonia, until now, a lack of genetic information has impeded exploration at the molecular level.We performed Illumina sequencing of central nervous system mRNAs from Tritonia, generating 133.1 million 100 base pair, paired-end reads. De novo reconstruction of the RNA-Seq data yielded a total of 185,546 contigs, which partitioned into 123,154 non-redundant gene clusters (unigenes. BLAST comparison with RefSeq and Swiss-Prot protein databases, as well as mRNA data from other invertebrates (gastropod molluscs: Aplysia californica, Lymnaea stagnalis and Biomphalaria glabrata; cnidarian: Nematostella vectensis revealed that up to 76,292 unigenes in the Tritonia transcriptome have putative homologues in other databases, 18,246 of which are below a more stringent E-value cut-off of 1x10-6. In silico prediction of secreted proteins from the Tritonia transcriptome shotgun assembly (TSA produced a database of 579 unique sequences of secreted proteins, which also exhibited markedly higher expression levels compared to other genes in the TSA.Our efforts greatly expand the availability of gene sequences available for Tritonia diomedea. We were able to extract full length protein sequences for most queried genes, including those involved in electrical excitability, synaptic vesicle release and neurotransmission, thus confirming that the transcriptome will serve as a useful tool for probing the molecular correlates of behavior in this species. We also generated a neurosecretome database that will serve as a useful tool for probing peptidergic signalling systems in the Tritonia brain.

  7. Determining metal assimilation efficiency in aquatic invertebrates using enriched stable metal isotope tracers

    International Nuclear Information System (INIS)

    Croteau, Marie-Noele; Luoma, Samuel N.; Pellet, Bastien

    2007-01-01

    We employ a novel approach that combines pulse-chase feeding and multi-labelled stable isotopes to determine gut passage time (GPT), gut retention time (GRT), food ingestion rate (IR) and assimilation efficiency (AE) of three trace elements for a freshwater gastropod. Lettuce isotopically enriched in 53 Cr, 65 Cu and 106 Cd was fed for 2 h to Lymnaea stagnalis. The release of tracers in feces and water was monitored for 48 h, during which unlabelled lettuce was provided ad libidum. The first defecation of 53 Cr occurred after 5 h of depuration (GPT), whereas 90% of the ingested 53 Cr was recovered in the feces after 22.5 h of depuration (GRT). 53 Chromium was not significantly accumulated in the soft tissues upon exposure. In contrast, 65 Cu and 106 Cd assimilation was detectable for most experimental snails, i.e., 65/63 Cu and 106/114 Cd ratios in exposed snails were higher than those for controls. Food IR during the labelled feeding phase was 0.16 ± 0.07 g g -1 d -1 . IR was inferred from the amount of 53 Cr egested in the feces during depuration and the concentration of 53 Cr in the labelled lettuce. Assimilation efficiencies (±95% CI) determined using mass balance calculations were 84 ± 4% for Cu and 85 ± 3% for Cd. The ratio method yields similar AE estimates. Expanding the application of this novel stable isotope tracer technique to other metals in a wide variety of species will provide unique opportunities to evaluate the interplay between digestive processes and dietary influx of metals. Understanding the biological processes that modulate dietborne metal uptake is crucial to assess the toxicity of dietborne metals

  8. Increase in cyclic AMP concentration in a cerebral giant interneuron mimics part of a memory trace for conditioned taste aversion of the pond snail.

    Science.gov (United States)

    Otsuka, Emi; Matsunaga, Miho; Okada, Ryuichi; Yamagishi, Miki; Okuta, Akiko; Lukowiak, Ken; Ito, Etsuro

    2013-01-01

    Conditioned taste aversion (CTA) can be classically conditioned in the pond snail Lymnaea stagnalis and subsequently be consolidated into long-term memory (LTM). The neural trace that subserves CTA-LTM can be summarized as follows: A polysynaptic inhibitory postsynaptic potential recorded in the neuron 1 medial (N1M) cell in the conditioned snails as a result of activation of the cerebral giant cell (CGC) is larger and lasts longer than that in control snails. The N1M cell is ultimately activated by the CGC via the neuron 3 tonic (N3t) cell. That is, the inhibitory monosynaptic inputs from the N3t cell to the N1M cell are facilitated. The N1M and N3t cells are the members of feeding central pattern generator, whereas the CGC is a multimodal interneuron thought to play a key role in feeding behavior. Here we examined the involvement of a second messenger, cAMP, in the establishment of the memory trace. We injected cAMP into the CGC and monitored the potentials of the B3 motor neuron activated by the CGC. B3 activity is used as an index for the synaptic inputs from the N3t cell to the N1M cell. We found that the B3 potentials were transiently enlarged. Thus, when the cAMP concentration is increased in the CGC by taste aversion training, cAMP-induced changes may play a key role in the establishment of a memory trace in the N3t cell.

  9. Altered gene activity correlated with long-term memory formation of conditioned taste aversion in Lymnaea.

    Science.gov (United States)

    Azami, Sachiyo; Wagatsuma, Akiko; Sadamoto, Hisayo; Hatakeyama, Dai; Usami, Takeshi; Fujie, Manabu; Koyanagi, Ryo; Azumi, Kaoru; Fujito, Yutaka; Lukowiak, Ken; Ito, Etsuro

    2006-11-15

    The pond snail Lymnaea stagnalis is capable of learning conditioned taste aversion (CTA) and then consolidating that learning into long-term memory (LTM) that persists for at least 1 month. LTM requires de novo protein synthesis and altered gene activity. Changes in gene activity in Lymnaea that are correlated with, much less causative, memory formation have not yet been identified. As a first step toward rectifying this situation, we constructed a cDNA microarray with mRNAs extracted from the central nervous system (CNS) of Lymnaea. We then, using this microarray assay, identified genes whose activity either increased or decreased following CTA memory consolidation. We also identified genes whose expression levels were altered after inhibition of the cyclic AMP response element-binding protein (CREB) that is hypothesized to be a key transcription factor for CTA memory. We found that the molluscan insulin-related peptide II (MIP II) was up-regulated during CTA-LTM, whereas the gene encoding pedal peptide preprohormone (Pep) was down-regulated by CREB2 RNA interference. We next examined mRNAs of MIP II and Pep using real-time RT-PCR with SYBR Green. The MIP II mRNA level in the CNS of snails exhibiting "good" memory for CTA was confirmed to be significantly higher than that from the CNS of snails exhibiting "poor" memory. In contrast, there was no significant difference in expression levels of the Pep mRNA between "good" and "poor" performers. These data suggest that in Lymnaea MIP II may play a role in the consolidation process that forms LTM following CTA training.

  10. One-trial conditioned taste aversion in Lymnaea: good and poor performers in long-term memory acquisition.

    Science.gov (United States)

    Sugai, Rio; Azami, Sachiyo; Shiga, Hatsuki; Watanabe, Takayuki; Sadamoto, Hisayo; Kobayashi, Suguru; Hatakeyama, Dai; Fujito, Yutaka; Lukowiak, Ken; Ito, Etsuro

    2007-04-01

    In the majority of studies designed to elucidate the causal mechanisms of memory formation, certain members of the experimental cohort, even though subjected to exactly the same conditioning procedures, remember significantly better than others, whereas others show little or no long-term memory (LTM) formation. To begin to address the question of why this phenomenon occurs and thereby help clarify the causal mechanism of LTM formation, we used a conditioned taste aversion (CTA) procedure on individuals of the pond snail Lymnaea stagnalis and analyzed their subsequent behavior. Using sucrose as an appetitive stimulus and KCl as an aversive stimulus, we obtained a constant ratio of ;poor' to ;good' performers for CTA-LTM. We found that approximately 40% of trained snails possessed LTM following a one-trial conditioning procedure. When we examined the time-window necessary for the memory consolidation, we found that if we cooled snails to 4 degrees C for 30 min within 10 min after the one-trial conditioning, LTM was blocked. However, with delayed cooling (i.e. longer than 10 min), LTM was present. We could further interfere with LTM formation by inducing inhibitory learning (i.e. backward conditioning) after the one-trial conditioning. Finally, we examined whether we could motivate snails to acquire LTM by depriving them of food for 5 days before the one-trial conditioning. Food-deprived snails, however, failed to exhibit LTM following the one-trial conditioning. These results will help us begin to clarify why some individuals are better at learning and forming memory for specific tasks at the neuronal level.

  11. What are the elements of motivation for acquisition of conditioned taste aversion?

    Science.gov (United States)

    Mita, Koichi; Okuta, Akiko; Okada, Ryuichi; Hatakeyama, Dai; Otsuka, Emi; Yamagishi, Miki; Morikawa, Mika; Naganuma, Yuki; Fujito, Yutaka; Dyakonova, Varvara; Lukowiak, Ken; Ito, Etsuro

    2014-01-01

    The pond snail Lymnaea stagnalis is capable of being classically conditioned to avoid food and to consolidate this aversion into a long-term memory (LTM). Previous studies have shown that the length of food deprivation is important for both the acquisition of taste aversion and its consolidation into LTM, which is referred to as conditioned taste aversion (CTA). Here we tested the hypothesis that the hemolymph glucose concentration is an important factor in the learning and memory of CTA. One-day food deprivation resulted in the best learning and memory, whereas more prolonged food deprivation had diminishing effects. Five-day food deprivation resulted in snails incapable of learning or remembering. During this food deprivation period, the hemolymph glucose concentration decreased. If snails were fed for 2days following the 5-day food deprivation, their glucose levels increased significantly and they exhibited both learning and memory, but neither learning nor memory was as good as with the 1-day food-deprived snails. Injection of the snails with insulin to reduce glucose levels resulted in better learning and memory. Insulin is also known to cause a long-term enhancement of synaptic transmission between the feeding-related neurons. On the other hand, injection of glucose into 5-day food-deprived snails did not alter their inability to learn and remember. However, if these snails were fed on sucrose for 3min, they then exhibited learning and memory formation. Our data suggest that hemolymph glucose concentration is an important factor in motivating acquisition of CTA in Lymnaea and that the action of insulin in the brain and the feeding behavior are also important factors. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Molecular cloning and transcriptional analysis of a NPY receptor-like in common Chinese cuttlefish Sepiella japonica

    Science.gov (United States)

    Yang, Jingwen; Xu, Yuchao; Xu, Ke; Ping, Hongling; Shi, Huilai; Lü, Zhenming; Wu, Changwen; Wang, Tianming

    2017-08-01

    Neuropeptide Y (NPY) has a pivotal role in the regulation of many physiological processes. In this study, the gene encoding a NPY receptor-like from the common Chinese cuttlefish Sepiella japonica (SjNPYR-like) was identified and characterized. The full-length SjNPYR-like cDNA was cloned containing a 492-bp of 5' untranslated region (UTR), 1 182 bp open reading frame (ORF) encoding a protein of 393 amino acid residues, and 228 bp of 3' UTR. The putative protein was predicted to have a molecular weight of 45.54 kDa and an isoelectric point (pI) of 8.13. By informatic analyses, SjNPYR-like was identified as belonging to the class A G protein coupled receptor (GPCR) family (the rhodopsin-type). The amino acid sequence contained 12 potential phosphorylation sites and five predicted N-linked glycosylation sites. Multiple sequence alignment and 3D structure modeling were conducted to clarify SjNPYR bioinformatics characteristics. Phylogenetic analysis identifies it as an NPYR with identity of 33% to Lymnaea stagnalis NPFR. Transmembrane properties of SjNPYR-like were demonstrated in vitro using HEK293 cells and the pEGFP-N1 plasmid. Relative quantification of SjNPYR-like mRNA level confirmed a high level expression and broad distribution of SjNPYR - like in various tissues of female S. japonica. In addition, the transcriptional profile of SjNPYR - like in the brain, liver, and ovary during gonadal development was analyzed. The results provide basic understanding on the molecular characteristics of SjNPYR-like and its potentially physical functions.

  13. Effect of cysteine and humic acids on bioavailability of Ag from Ag nanoparticles to a freshwater snail

    Science.gov (United States)

    Luoma, Samuel N.; Tasha Stoiber,; Croteau, Marie-Noele; Isabelle Romer,; Ruth Merrifeild,; Lead, Jamie

    2016-01-01

    Metal-based engineered nanoparticles (NPs) will undergo transformations that will affect their bioavailability, toxicity and ecological risk when released to the environment, including interactions with dissolved organic material. The purpose of this paper is to determine how interactions with two different types of organic material affect the bioavailability of silver nanoparticles (AgNPs). Silver uptake rates by the pond snail Lymnaea stagnalis were determined after exposure to 25 nmol l-1 of Ag as PVP AgNPs, PEG AgNPs or AgNO3, in the presence of either Suwannee River humic acid or cysteine, a high-affinity thiol-rich organic ligand. Total uptake rate of Ag from the two NPs was either increased or not strongly affected in the presence of 1 – 10 mg 1-1 humic acid. Humic substances contain relatively few strong ligands for Ag explaining their limited effects on Ag uptake rate. In contrast, Ag uptake rate was substantially reduced by cysteine. Three components of uptake from the AgNPs were quantified in the presence of cysteine using a biodynamic modeling approach: uptake of dissolved Ag released by the AgNPs, uptake of a polymer or large (>3kD) Ag-cysteine complex and uptake of the nanoparticle itself. Addition of 1:1 Ag:cysteine reduced concentrations of dissolved Ag, which contributed to, but did not fully explain the reductions in uptake. A bioavailable Ag-cysteine complex (> 3kD) appeared to be the dominant avenue of uptake from both PVP AgNPs and PEG AgNPs in the presence of cysteine. Quantifying the different avenues of uptake sets the stage for studies to assess toxicity unique to NPs.

  14. Earthworm assemblages in different intensity of agricultural uses and their relation to edaphic variables

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    LB Falco

    2015-05-01

    Full Text Available The objective of this study was to relate earthworm assemblage structure with three different soil use intensities, and to indentify the physical, chemical, and microbiological soil variables that are associated to the observed differences. Three soil uses were evaluated: 1-Fifty year old naturalized grasslands, low use intensity; 2-Recent agricultural fields, intermediate use intensity, and 3-Fifty year old intensive agricultural fields, high use intensity. Three different sites for each soil use were evaluated from winter 2008 through summer 2011. Nine earthworm species were identified across all sampling sites. The sites shared five species: the native Microscolex dubius, and the introduced Aporrectodea caliginosa, A. rosea, Octalasion cyaneum, and O. lacteum, but they differed in relative abundance by soil use. The results show that the earthworm community structure is linked to and modulated by soil properties. Both species abundance and diversity showed significant differences depending on soil use intensity. A principal component analysis showed that species composition is closely related to the environmental variability. The ratio of native to exotic species was significantly lower in the intensive agricultural system when compared to the other two, lower disturbance systems. Microscolex dubius abundance was related to naturalized grasslands along with soil Ca, pH, mechanical resistance, and microbial respiration. Aporrectodea caliginosa abundance was related to high K levels, low enzymatic activity, slightly low pH, low Ca, and appeared related to the highly disturbed environment. Eukerria stagnalis and Aporrectodea rosea, commonly found in the recent agricultural system, were related to high soil moisture condition, low pH, low Ca and low enzymatic activity. These results show that earthworm assemblages can be good indicators of soil use intensities. In particular, Microscolex dubius, Aporrectodea caliginosa, and Aporrectodea rosea

  15. Ejaculates are not used as nuptial gifts in simultaneously hermaphroditic snails.

    Science.gov (United States)

    Lodi, Monica; Meijer, Fedde W; Koene, Joris M

    2017-08-01

    Promoted by sexual selection, males usually adopt different ways to increase their fertilization chances. In many insect taxa males donate nuptial gifts, together with sperm, which represent a valuable additional nutrient source that females can use to provision eggs. This has also been suggested to occur in simultaneous hermaphrodites, organisms with both sex functions. In theory, donation of nuptial gifts or extra nutrients might work in hermaphrodites that mate unilaterally (one-way donation of ejaculates), but will not be effective when these organisms mate reciprocally (mutual exchange of ejaculates), since on average each partner would receive the amount it also transfers. Hence, for the latter the net amount gained would be zero, and when considering the non-trivial costs of metabolic conversion the energy balance of this exchange ends up negative. To test this prediction, we measured the material (dry weight) and resource (carbon and nitrogen content) investment into ejaculates of the unilaterally mating freshwater snail Lymnaea stagnalis and spermatophores of the reciprocally mating land snail Cornu aspersum. When compared to eggs, our measurements indicate that the investment is low for ejaculates and spermatophores, neither of which represent a significant contribution to egg production. Importantly, during reciprocal matings, couples exchanged similar amounts of material and resources, thus a gain of extra substances seems irrelevant. Hence, caution is needed when generalizing functions of male reproductive strategies across mating systems. Although digestion of ejaculates does not provide extra material and resources in simultaneous hermaphrodites, their absorption could still be important to eliminate an excess of received sperm and to select sperm via cryptic female choice. Copyright © 2017 Elsevier GmbH. All rights reserved.

  16. Ecological modulation of environmental stress: interactions between ultraviolet radiation, epibiotic snail embryos, plants and herbivores.

    Science.gov (United States)

    Wahl, Martin

    2008-05-01

    1. The distribution of egg masses of the freshwater snails Lymnaea stagnalis and Planorbarius corneus on the undersides of water lily leaves (e.g. Nuphar lutea) is related to the prevalence of the leaf-mining beetle Galerucella nymphaeae. 2. When given the choice, Planorbarius significantly avoids leaves that were infested by the mining beetle. Conversely, Lymnaea did not discriminate against mined leaves. 3. Intact Nuphar leaves block over 95% of incident ultraviolet radiation. Yet, ultraviolet transmission reaches almost 100% under beetle mining scars. These are several times wider than snail embryos. 4. When exposed to natural sunlight, Lymnaea embryos proved to be resistant to ambient ultraviolet, while Planorbarius embryos were rapidly killed. Thus, one selective advantage of Planorbarius discrimination against mined leaves when depositing its eggs could be the avoidance of ultraviolet radiation passing through mining scars. 5. Other mining-related modifications of the leaves, reduced area, decreased longevity, altered aufwuchs (i.e. biofilm and epibionts) are discussed but seem less relevant for the oviposition preference of Planorbarius. 6. The discriminatory behaviour of this snail species was triggered by water-borne cues emitted by the damaged leaf, not by the eggs or larvae of the beetle. 7. This study illustrates how environmental stress on a given species, ultraviolet radiation in this case, can be ecologically buffered (shading by Nuphar) or enhanced (reduction of Nuphar shading through beetle mining) by associated species. It highlights how the impact of a given stress depends on the identity of the target species as well as on the identity and role of other species in the community.

  17. Toxicity of aluminium in natural waters controlled by type rather than quantity of natural organic matter

    International Nuclear Information System (INIS)

    Papathanasiou, Grigorios; White, Keith N.; Walton, Rachel; Boult, Stephen

    2011-01-01

    Extension of the conditions under which Al toxicity is tested is required. Environmentally representative preparation of waters is used in investigating roles of alginate (AA) and humic acids (HA) in partitioning of Al (0.5 mg L -1 ), subsequent uptake and accumulation by and toxicity to Lymnaea stagnalis. HA and AA did not alter precipitation of Al(OH) 3 , but altered subsequent behaviour of Al. High (40 mg L -1 ) HA concentrations, and to a lesser extent AA, prevented settling and availability for benthic grazing but made deposited Al more likely to be ingested. HA detoxified but AA increased toxicity relative to Al alone. Low concentration (4 mg L -1 ) AA and HA do not change partitioning but increase uptake; they both detoxify, but AA less than HA. The study shows OC:Al ratio is critical in predicting Al behaviour in natural waters, also uptake is mediated by snail behaviour, not solely a function of concentration and form of Al. Therefore, predicting Al behaviour will be subject to errors in determining relevant water composition and response of biota to the new speciation. However, with respect to toxicity, rather than other aspects of Al behaviour, different ratios of HA and Al are insignificant compared to whether AA is present rather than HA. - Highlights: → Toxicity assessment in which environmental relevance is of primary concern. → Mass balance of Al monitored throughout the exposure period. → Al behaviour influenced by concentration of organic matter. → Strong dependence of toxicity on type rather than concentration of organic matter. → Toxicity is a function of Al behaviour but also animal behaviour.

  18. Responses of neurons to extreme osmomechanical stress.

    Science.gov (United States)

    Wan, X; Harris, J A; Morris, C E

    1995-05-01

    Neurons are often regarded as fragile cells, easily destroyed by mechanical and osmotic insult. The results presented here demonstrate that this perception needs revision. Using extreme osmotic swelling, we show that molluscan neurons are astonishingly robust. In distilled water, a heterogeneous population of Lymnaea stagnalis CNS neurons swelled to several times their initial volume, yet had a ST50 (survival time for 50% of cells) > 60 min. Cells that were initially bigger survived longer. On return to normal medium, survivors were able, over the next 24 hr, to rearborize. Reversible membrane capacitance changes corresponding to about 0.7 muF/cm2 of apparent surface area accompanied neuronal swelling and shrinking in hypo- and hyperosmotic solutions; reversible changes in cell surface area evidently contributed to the neurons' ability to accommodate hydrostatic pressures then recover. The reversible membrane area/capacitance changes were not dependent on extracellular Ca2+. Neurons were monitored for potassium currents during direct mechanical inflation and during osmotically driven inflation. The latter but not the former stimulus routinely elicited small potassium currents, suggesting that tension increases activate the currents only if additional disruption of the cortex has occurred. Under stress in distilled water, a third of the neurons displayed a quite unexpected behavior: prolonged writhing of peripheral regions of the soma. This suggested that a plasma membrane-linked contractile machinery (presumably actomyosin) might contribute to the neurons' mechano-osmotic robustness by restricting water influx. Consistent with this possibility, 1 mM N-ethyl-maleimide, which inhibits myosin ATPase, decreased the ST50 to 18 min, rendered the survival time independent of initial size, and abolished writhing activity. For neurons, active mechanical resistance of the submembranous cortex, along with the mechanical compliance supplied by insertion or eversion of membrane

  19. Learning-dependent gene expression of CREB1 isoforms in the molluscan brain

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    Hisayo Sadamoto

    2010-05-01

    Full Text Available Cyclic AMP-responsive element binding protein1 (CREB1 has multiple functions in gene regulation. Various studies have reported that CREB1-dependent gene induction is necessary for memory formation and long-lasting behavioral changes in both vertebrates and invertebrates. In the present study, we characterized Lymnaea CREB1 (LymCREB1 mRNA isoforms of spliced variants in the central nervous system (CNS of the pond snail Lymnaea stagnalis. Among these spliced variants, the three isoforms that code a whole LymCREB1 protein are considered to be the activators for gene regulation. The other four isoforms, which code truncated LymCREB1 proteins with no kinase inducible domain, are the repressors. For a better understanding of the possible roles of different LymCREB1 isoforms, the expression level of these isoform mRNAs was investigated by a real-time quantitative RT-PCR method. Further, we examined the changes in gene expression for all the isoforms in the CNS after conditioned taste aversion (CTA learning or backward conditioning as a control. The results showed that CTA learning increased LymCREB1 gene expression, but it did not change the activator/repressor ratio. Our findings showed that the repressor isoforms, as well as the activator ones, are expressed in large amounts in the CNS, and the gene expression of CREB1 isoforms appeared to be specific for the given stimulus. This was the first quantitative analysis of the expression patterns of CREB1 isoforms at the mRNA level and their association with learning behavior.

  20. Dose-dependent effects of the clinical anesthetic isoflurane on Octopus vulgaris: a contribution to cephalopod welfare.

    Science.gov (United States)

    Polese, Gianluca; Winlow, William; Di Cosmo, Anna

    2014-12-01

    Recent progress in animal welfare legislation relating to invertebrates has provoked interest in methods for the anesthesia of cephalopods, for which different approaches to anesthesia have been tried but in most cases without truly anesthetizing the animals. For example, several workers have used muscle relaxants or hypothermia as forms of "anesthesia." Several inhalational anesthetics are known to act in a dose-dependent manner on the great pond snail Lymnaea stagnalis, a pulmonate mollusk. Here we report, for the first time, on the effects of clinical doses of the well-known inhalational clinical anesthetic isoflurane on the behavioral responses of the common octopus Octopus vulgaris. In each experiment, isoflurane was equilibrated into a well-aerated seawater bath containing a single adult O. vulgaris. Using a web camera, we recorded each animal's response to touch stimuli eliciting withdrawal of the arms and siphon and observed changes in the respiratory rate and the chromatophore pattern over time (before, during, and after application of the anesthetic). We found that different animals of the same size responded with similar behavioral changes as the isoflurane concentration was gradually increased. After gradual application of 2% isoflurane for a maximum of 5 min (at which time all the responses indicated deep anesthesia), the animals recovered within 45-60 min in fresh aerated seawater. Based on previous findings in gastropods, we believe that the process of anesthesia induced by isoflurane is similar to that previously observed in Lymnaea. In this study we showed that isoflurane is a good, reversible anesthetic for O. vulgaris, and we developed a method for its use.

  1. Accumulation of uranium by aquatic plants in field conditions: Prospects for phytoremediation

    International Nuclear Information System (INIS)

    Favas, Paulo J.C.; Pratas, João; Varun, Mayank; D'Souza, Rohan; Paul, Manoj S.

    2014-01-01

    A study was undertaken to determine Uranium concentrations in water and aquatic plants in the uraniferous region of Beiras, Central Portugal. Samples were collected from running water (n = 200) at places where aquatic species were observed. Plant samples were collected from 28 species of submerged, free-floating and rooted emergent plants including 2 bryophytes and 1 pteridophyte. Uranium concentrations in surface waters ranged from 0.23 to 1217 μg L −1 . The aquatic plant species studied, including several previously untested species, exhibited the ability to accumulate U in concentrations many times that of the ambient water. In general submerged plants exhibited higher U content followed by rooted emergent and free floating species. The highest U concentrations were observed in the bryophyte Fontinalis antipyretica (up to 4979 mg kg −1 ) followed by Callitriche stagnalis (1963 mg kg −1 ), Callitriche hamulata (379 mg kg −1 ), Ranunculus peltatus subsp. saniculifolius (243 mg kg −1 ), Callitriche lusitanica (218 mg kg −1 ), and Ranunculus trichophyllus (65.8 mg kg −1 ). In two out of three rooted emergent species U seemed to be preferentially partitioned in rhizome/roots with highest rhizome U content recorded in Typha latifolia (380 mg kg −1 ). Among the free-floating species, the highest U content (42.5 mg kg −1 ) was seen in Lemna minor. The bryophyte F. antipyretica and Callitrichaceae members seem to be promising candidates for the development of phytofiltration methodologies based on U accumulation, abundance and biomass production. - Highlights: • Exploration of U contamination extent in uraniferous province of Central Portugal • A group of previously untested species with the ability to accumulate U was assessed • U accumulation patterns in the species indicate their potential in bioindication and phytoremediation of U-contaminated water

  2. The calmodulin-binding, short linear motif, NSCaTE is conserved in L-type channel ancestors of vertebrate Cav1.2 and Cav1.3 channels.

    Directory of Open Access Journals (Sweden)

    Valentina Taiakina

    Full Text Available NSCaTE is a short linear motif of (xWxxx(I or Lxxxx, composed of residues with a high helix-forming propensity within a mostly disordered N-terminus that is conserved in L-type calcium channels from protostome invertebrates to humans. NSCaTE is an optional, lower affinity and calcium-sensitive binding site for calmodulin (CaM which competes for CaM binding with a more ancient, C-terminal IQ domain on L-type channels. CaM bound to N- and C- terminal tails serve as dual detectors to changing intracellular Ca(2+ concentrations, promoting calcium-dependent inactivation of L-type calcium channels. NSCaTE is absent in some arthropod species, and is also lacking in vertebrate L-type isoforms, Cav1.1 and Cav1.4 channels. The pervasiveness of a methionine just downstream from NSCaTE suggests that L-type channels could generate alternative N-termini lacking NSCaTE through the choice of translational start sites. Long N-terminus with an NSCaTE motif in L-type calcium channel homolog LCav1 from pond snail Lymnaea stagnalis has a faster calcium-dependent inactivation than a shortened N-termini lacking NSCaTE. NSCaTE effects are present in low concentrations of internal buffer (0.5 mM EGTA, but disappears in high buffer conditions (10 mM EGTA. Snail and mammalian NSCaTE have an alpha-helical propensity upon binding Ca(2+-CaM and can saturate both CaM N-terminal and C-terminal domains in the absence of a competing IQ motif. NSCaTE evolved in ancestors of the first animals with internal organs for promoting a more rapid, calcium-sensitive inactivation of L-type channels.

  3. A homolog of the vertebrate pituitary adenylate cyclase-activating polypeptide is both necessary and instructive for the rapid formation of associative memory in an invertebrate.

    Science.gov (United States)

    Pirger, Zsolt; László, Zita; Kemenes, Ildikó; Tóth, Gábor; Reglodi, Dóra; Kemenes, György

    2010-10-13

    Similar to other invertebrate and vertebrate animals, cAMP-dependent signaling cascades are key components of long-term memory (LTM) formation in the snail Lymnaea stagnalis, an established experimental model for studying evolutionarily conserved molecular mechanisms of long-term associative memory. Although a great deal is already known about the signaling cascades activated by cAMP, the molecules involved in the learning-induced activation of adenylate cyclase (AC) in Lymnaea remained unknown. Using matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy in combination with biochemical and immunohistochemical methods, recently we have obtained evidence for the existence of a Lymnaea homolog of the vertebrate pituitary adenylate cyclase-activating polypeptide (PACAP) and for the AC-activating effect of PACAP in the Lymnaea nervous system. Here we first tested the hypothesis that PACAP plays an important role in the formation of robust LTM after single-trial classical food-reward conditioning. Application of the PACAP receptor antagonist PACAP6-38 around the time of single-trial training with amyl acetate and sucrose blocked associative LTM, suggesting that in this "strong" food-reward conditioning paradigm the activation of AC by PACAP was necessary for LTM to form. We found that in a "weak" multitrial food-reward conditioning paradigm, lip touch paired with sucrose, memory formation was also dependent on PACAP. Significantly, systemic application of PACAP at the beginning of multitrial tactile conditioning accelerated the formation of transcription-dependent memory. Our findings provide the first evidence to show that in the same nervous system PACAP is both necessary and instructive for fast and robust memory formation after reward classical conditioning.

  4. Natural Compounds Interacting with Nicotinic Acetylcholine Receptors: From Low-Molecular Weight Ones to Peptides and Proteins

    Directory of Open Access Journals (Sweden)

    Denis Kudryavtsev

    2015-05-01

    Full Text Available Nicotinic acetylcholine receptors (nAChRs fulfill a variety of functions making identification and analysis of nAChR subtypes a challenging task. Traditional instruments for nAChR research are d-tubocurarine, snake venom protein α-bungarotoxin (α-Bgt, and α-conotoxins, neurotoxic peptides from Conus snails. Various new compounds of different structural classes also interacting with nAChRs have been recently identified. Among the low-molecular weight compounds are alkaloids pibocin, varacin and makaluvamines C and G. 6-Bromohypaphorine from the mollusk Hermissenda crassicornis does not bind to Torpedo nAChR but behaves as an agonist on human α7 nAChR. To get more selective α-conotoxins, computer modeling of their complexes with acetylcholine-binding proteins and distinct nAChRs was used. Several novel three-finger neurotoxins targeting nAChRs were described and α-Bgt inhibition of GABA-A receptors was discovered. Information on the mechanisms of nAChR interactions with the three-finger proteins of the Ly6 family was found. Snake venom phospholipases A2 were recently found to inhibit different nAChR subtypes. Blocking of nAChRs in Lymnaea stagnalis neurons was shown for venom C-type lectin-like proteins, appearing to be the largest molecules capable to interact with the receptor. A huge nAChR molecule sensible to conformational rearrangements accommodates diverse binding sites recognizable by structurally very different compounds.

  5. Marine Natural Products Acting on the Acetylcholine-Binding Protein and Nicotinic Receptors: From Computer Modeling to Binding Studies and Electrophysiology

    Directory of Open Access Journals (Sweden)

    Denis Kudryavtsev

    2014-03-01

    Full Text Available For a small library of natural products from marine sponges and ascidians, in silico docking to the Lymnaea stagnalis acetylcholine-binding protein (AChBP, a model for the ligand-binding domains of nicotinic acetylcholine receptors (nAChRs, was carried out and the possibility of complex formation was revealed. It was further experimentally confirmed via competition with radioiodinated α-bungarotoxin ([125I]-αBgt for binding to AChBP of the majority of analyzed compounds. Alkaloids pibocin, varacin and makaluvamines С and G had relatively high affinities (Ki 0.5–1.3 μM. With the muscle-type nAChR from Torpedo californica ray and human neuronal α7 nAChR, heterologously expressed in the GH4C1 cell line, no competition with [125I]-αBgt was detected in four compounds, while the rest showed an inhibition. Makaluvamines (Ki ~ 1.5 μM were the most active compounds, but only makaluvamine G and crambescidine 359 revealed a weak selectivity towards muscle-type nAChR. Rhizochalin, aglycone of rhizochalin, pibocin, makaluvamine G, monanchocidin, crambescidine 359 and aaptamine showed inhibitory activities in electrophysiology experiments on the mouse muscle and human α7 nAChRs, expressed in Xenopus laevis oocytes. Thus, our results confirm the utility of the modeling studies on AChBPs in a search for natural compounds with cholinergic activity and demonstrate the presence of the latter in the analyzed marine biological sources.

  6. Balanced plasticity and stability of the electrical properties of a molluscan modulatory interneuron after classical conditioning: a computational study

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    Dimitris Vavoulis

    2010-05-01

    Full Text Available The Cerebral Giant Cells (CGCs are a pair of identified modulatory interneurons in the Central Nervous System of the pond snail Lymnaea stagnalis with an important role in the expression of both unconditioned and conditioned feeding behavior. Following single-trial food-reward classical conditioning, the membrane potential of the CGCs becomes persistently depolarized. This depolarization contributes to the conditioned response by facilitating sensory cell to command neuron synapses, which results in the activation of the feeding network by the conditioned stimulus. Despite the depolarization of the membrane potential, which enables the CGGs to play a key role in learning-induced network plasticity, there is no persistent change in the tonic firing rate or shape of the action potentials, allowing these neurons to retain their normal network function in feeding. In order to understand the ionic mechanisms of this novel combination of plasticity and stability of intrinsic electrical properties, we first constructed and validated a Hodgkin-Huxley-type model of the CGCs. We then used this model to elucidate how learning-induced changes in a somal persistent sodium and a delayed rectifier potassium current lead to a persistent depolarization of the CGCs whilst maintaining their firing rate. Including in the model an additional increase in the conductance of a high-voltage-activated calcium current allowed the spike amplitude and spike duration also to be maintained after conditioning. We conclude therefore that a balanced increase in three identified conductances is sufficient to explain the electrophysiological changes found in the CGCs after classical conditioning.

  7. Accumulation of uranium by aquatic plants in field conditions: Prospects for phytoremediation

    Energy Technology Data Exchange (ETDEWEB)

    Favas, Paulo J.C., E-mail: pjcf@utad.pt [School of Life Sciences and the Environment, University of Trás-os-Montes e Alto Douro, 5001-801 Vila Real (Portugal); IMAR-CMA Marine and Environmental Research Centre, Faculty of Sciences and Technology, University of Coimbra, 3001-401 Coimbra (Portugal); Pratas, João [Department of Earth Sciences, Faculty of Sciences and Technology, University of Coimbra, 3001-401 Coimbra (Portugal); IMAR-CMA Marine and Environmental Research Centre, Faculty of Sciences and Technology, University of Coimbra, 3001-401 Coimbra (Portugal); Varun, Mayank; D' Souza, Rohan; Paul, Manoj S. [Department of Botany, St. John' s College, Agra 282 002 (India)

    2014-02-01

    A study was undertaken to determine Uranium concentrations in water and aquatic plants in the uraniferous region of Beiras, Central Portugal. Samples were collected from running water (n = 200) at places where aquatic species were observed. Plant samples were collected from 28 species of submerged, free-floating and rooted emergent plants including 2 bryophytes and 1 pteridophyte. Uranium concentrations in surface waters ranged from 0.23 to 1217 μg L{sup −1}. The aquatic plant species studied, including several previously untested species, exhibited the ability to accumulate U in concentrations many times that of the ambient water. In general submerged plants exhibited higher U content followed by rooted emergent and free floating species. The highest U concentrations were observed in the bryophyte Fontinalis antipyretica (up to 4979 mg kg{sup −1}) followed by Callitriche stagnalis (1963 mg kg{sup −1}), Callitriche hamulata (379 mg kg{sup −1}), Ranunculus peltatus subsp. saniculifolius (243 mg kg{sup −1}), Callitriche lusitanica (218 mg kg{sup −1}), and Ranunculus trichophyllus (65.8 mg kg{sup −1}). In two out of three rooted emergent species U seemed to be preferentially partitioned in rhizome/roots with highest rhizome U content recorded in Typha latifolia (380 mg kg{sup −1}). Among the free-floating species, the highest U content (42.5 mg kg{sup −1}) was seen in Lemna minor. The bryophyte F. antipyretica and Callitrichaceae members seem to be promising candidates for the development of phytofiltration methodologies based on U accumulation, abundance and biomass production. - Highlights: • Exploration of U contamination extent in uraniferous province of Central Portugal • A group of previously untested species with the ability to accumulate U was assessed • U accumulation patterns in the species indicate their potential in bioindication and phytoremediation of U-contaminated water.

  8. Six types of multistability in a neuronal model based on slow calcium current.

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    Tatiana Malashchenko

    Full Text Available BACKGROUND: Multistability of oscillatory and silent regimes is a ubiquitous phenomenon exhibited by excitable systems such as neurons and cardiac cells. Multistability can play functional roles in short-term memory and maintaining posture. It seems to pose an evolutionary advantage for neurons which are part of multifunctional Central Pattern Generators to possess multistability. The mechanisms supporting multistability of bursting regimes are not well understood or classified. METHODOLOGY/PRINCIPAL FINDINGS: Our study is focused on determining the bio-physical mechanisms underlying different types of co-existence of the oscillatory and silent regimes observed in a neuronal model. We develop a low-dimensional model typifying the dynamics of a single leech heart interneuron. We carry out a bifurcation analysis of the model and show that it possesses six different types of multistability of dynamical regimes. These types are the co-existence of 1 bursting and silence, 2 tonic spiking and silence, 3 tonic spiking and subthreshold oscillations, 4 bursting and subthreshold oscillations, 5 bursting, subthreshold oscillations and silence, and 6 bursting and tonic spiking. These first five types of multistability occur due to the presence of a separating regime that is either a saddle periodic orbit or a saddle equilibrium. We found that the parameter range wherein multistability is observed is limited by the parameter values at which the separating regimes emerge and terminate. CONCLUSIONS: We developed a neuronal model which exhibits a rich variety of different types of multistability. We described a novel mechanism supporting the bistability of bursting and silence. This neuronal model provides a unique opportunity to study the dynamics of networks with neurons possessing different types of multistability.

  9. AN ANALYSIS OF FIGURATIVE LANGUAGES USED IN COELHOS’S NOVEL ENTITLED “ALCHEMIST”

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    Trisna Dinillah Harya

    2017-05-01

    Full Text Available The title of this study is, “An Analysis of Figurative Languages Used in Paulo Coelho’s novel Entitled “The Alchemist”. The objectives of the study are to describe the types of the figurative language found in the book and to identify the contextual meaning of the figurative language. The method used in collecting the data related to the subject of this research is documentation method because the researcher collected the data from novel. This study was conducted by collecting any relevant data and information about the topic or problem of the study from novels and internet that are available for the analysis. The data collection used the following steps: reading the novel, and then selecting the data that used the types of figurative language. While the steps to analyze the data are identifying the types of figurative language according to Leech, identifying the contextual meaning of the figurative language, and the last is interpreting the data.The result shows that there are 70 sentences that have figurative language. From all the sentences, there are 30 items or 42.9% of simile, 27 items or 38.6% of personification, 12 items or 17.1% of metaphor, and 1 item or 1.4% of hyperbole. It can be indicated that the dominant type of figurative language in the novel is simile. The author uses simile to explain circumstances, to describe the characters, to express emotion of the characters, and to make his writing more vivid and entertaining. It can be concluded that figurative language has important roles in this novel. That‘s why the author used so many sentences that have figurative language in this novel. Using figurative language makes the novel more interesting to read, and helps the readers to imagine the story, the character based on the illustration that the author has already given in the story.

  10. Bioaccumulation of radionuclides in fertilized Canadian Shield lake basins

    International Nuclear Information System (INIS)

    Bird, G.A.; Schwartz, W.J.; Hesslein, R.H.; Mills, K.H.; Turner, M.A.

    1998-01-01

    Radionuclide tracers of heavy metals ( 59 Fe, 60 Co, 65 Zn, 75 Se 85 Sr, 134 Cs and 203 Hg) representing potential contamination from nuclear power plants, industry and agriculture were added to separate basins of Lake 226, Experimental Lakes Area, northwestern Ontario. The two basins were part of a eutrophication experiment and differed in their trophic status; the north basin (L226N) was eutrophic whereas the south basin (L226S) was mesotrophic. Our objective was to determine the uptake of the radionuclides by biota and the effect of lake trophic status on their bioaccumulation. The trophic status of the lakes did not appear to have a marked effect on the accumulation of radionuclides by the biota. This may have been because of a mid-summer leakage of nutrients between the basins which enhanced primary production in L226S, because there is a time lag between primary production and the availability of the radionuclides to the fishes or because trophic status does not affect the uptake of at least some of these radionuclides. However, there was a tendency for faster uptake of the radionuclides in L226N by fish than L226S, but the differences were not significant. Concentrations in the biota generally decreased in the order: fathead minnow>pearl dace>tadpoles>slimy sculpin>leeches. Concentrations in biota generally decreased in the order: 65 Zn> 203 Hg> 75 Se> 134 Cs> 60 Co> 85 Sr= 59 Fe. Cobalt-60 concentrations in tadpoles were greater than in the other biota. Radionuclide concentrations in the tissues of lake whitefish indicated that uptake was predominately from food. Radionuclide concentrations were usually higher in the posterior gut, liver and kidney than in other tissues, whereas body burdens were generally high in the muscle for 75 Se, 134 Cs and 203 Hg; kidney and gut for 60 Co; and bone for 65 Zn and 75 Se. Mercury-203 burdens were also high in the bone and gut

  11. Esporulação do Hepatozoon caimani (Carini, 1909, parasita do Jacaré-de-papo-amarelo: Caiman Latirostris daud, no Culex dolosus (L. Arribálzaga

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    Samuel B. Pessôa

    1972-01-01

    Full Text Available Os autores descrevem a evolução esporogônica do Hepatozoon caimani (Carini, 1909, no Culex dolosus (L. Arribálzaga. Após descreverem as formas eritrocíticas e pequenos cistos esquizogônicos com dois merozoítas, mostraram que a evolução do parasita no mosquito é muito lenta, pois leva cerca de 24 dias para a formação de esporozoítas, à temperatura de 26 a 28ºC e umidade relativa de 80 a 85%. Em geral, há formação nos oocistos de dois esporoblastos, sendo que um degenera e o outro evolui e forma cerca de 100 a 120 esporocistos, cada um contendo de 15 a 20 esporozoítas. Não conseguiram obter a evolução esporogônica dos parasitas em sanguessugas (Haementeria lutzi e nem em "barbeiros" (Triatoma infestans.The authors describe the sporogonic evolution of Hepatozoon caimani (Carini, 1909, in Culex dolosus (L. Arribálzaga. After describing the erythrocytic forms and the small schizogonic cysts with two merozoites, they show that the evolution of the parasite in mosquitoes is slow, taking about 24 days to form sporozoites at a temperature of 26-28ºC, and a relative humidity of 80-85%. Generally, two sporoblasts develop within the oocysts, one of them degenerating, while the other evolves and forms about 100 to 120 sporocysts, each containing from 15 to 20 sporozoites. No sporogonic evolution of the parasites has been achieved, neither in leeches (Haementeria lutzi nor in "barbeiros" (Triatoma infestans.

  12. Conformal field theories, representations and lattice constructions

    International Nuclear Information System (INIS)

    Dolan, L.; Montague, P.

    1996-01-01

    An account is given of the structure and representations of chiral bosonic meromorphic conformal field theories (CFT's), and, in particular, the conditions under which such a CFT may be extended by a representation to form a new theory. This general approach is illustrated by considering the untwisted and Z 2 -twisted theories, H(Λ) and H(Λ) respectively, which may be constructed from a suitable even Euclidean lattice Λ. Similarly, one may construct lattices Λ C and Lambda C by analogous constructions from a doubly-even binary code C. In the case when C is self-dual, the corresponding lattices are also. Similarly, H(Λ) and H(Λ) are self-dual if and only if Λ is. We show that H(Λ C ) has a natural triality structure, which induces an isomorphism H(Λ C )≡H(Λ C ) and also a triality structure on H(Λ C ). For C the Golay code, Λ C is the Leech lattice, and the triality on H(Λ C ) is the symmetry which extends the natural action of (an extension of) Conway's group on this theory to the Monster, so setting triality and Frenkel, Lepowsky and Meurman's construction of the natural Monster module in a more general context. The results also serve to shed some light on the classification of self-dual CFT's. We find that of the 48 theories H(Λ) and H(Λ) with central charge 24 that there are 39 distinct ones, and further that all 9 coincidences are accounted for by the isomorphism detailed above, induced by the existence of a doubly-even self-dual binary code. (orig.). With 8 figs., 2 tabs

  13. Monitoring of some Wild Plant Species Grown on Natural Radioactive Soils, Wadi EI -Gemal Area, Southeastern Desert, Egypt

    International Nuclear Information System (INIS)

    Morsy, A.M.A.; Afifi, S.Y.

    2008-01-01

    Fore long time ago, human kind has relied on natural products of plants as a primary source for medicine. Herbs, flora, molt and even leeches were employed to bring up relief to the sick and infirmly. As a part of ongoing investigations for the effect of natural radionuclide radiations on biochemical constituents of plants, .two native species (Salvadora persica and Balanites aegyptiaca). grown on virgin radionuclide soils along with Wadi EI-Gemal area, Southeastern Desert, Egypt were collected. This study dealt with amounts of radionuclide taken by plants and their effects on their biochemical constituents, beneficiation uses on remedy of contaminated and even polluted soils and sick treatments as well as exploration of radioactive materials. These plant samples were subjected to certain analysis techniques for the amounts of uranium that were followed by determining carbohydrates, lipids and proteins. The results indicated that both plants uptake uranium but with different amounts. Uranium has a passive effect on the total soluble suger (T.S.S.) of Balanties aegyptiaca plant, while no clear trend appears on T.S.S. of Snlvndora persica root samples. No clear trend appeared for effect of uranium on both fatty acids and amino acids of the investigated plants. Meanwhile uranium has a passive effect on saponin in both plant species, alkaloid in S. persica root and flavonoids in B. aegyptiaca fruits, while showed a positive effect on alkaloids in B. aegyptiaca and no clear trend appeared for flavonoids in S. persica. As for diosgenin uranium has passive effect on its amount in B. aegyptiaca

  14. Muscle organizers in Drosophila: the role of persistent larval fibers in adult flight muscle development

    Science.gov (United States)

    Farrell, E. R.; Fernandes, J.; Keshishian, H.

    1996-01-01

    In many organisms muscle formation depends on specialized cells that prefigure the pattern of the musculature and serve as templates for myoblast organization and fusion. These include muscle pioneers in insects and muscle organizing cells in leech. In Drosophila, muscle founder cells have been proposed to play a similar role in organizing larval muscle development during embryogenesis. During metamorphosis in Drosophila, following histolysis of most of the larval musculature, there is a second round of myogenesis that gives rise to the adult muscles. It is not known whether muscle founder cells organize the development of these muscles. However, in the thorax specific larval muscle fibers do not histolyze at the onset of metamorphosis, but instead serve as templates for the formation of a subset of adult muscles, the dorsal longitudinal flight muscles (DLMs). Because these persistent larval muscle fibers appear to be functioning in many respects like muscle founder cells, we investigated whether they were necessary for DLM development by using a microbeam laser to ablate them singly and in combination. We found that, in the absence of the larval muscle fibers, DLMs nonetheless develop. Our results show that the persistent larval muscle fibers are not required to initiate myoblast fusion, to determine DLM identity, to locate the DLMs in the thorax, or to specify the total DLM fiber volume. However, they are required to regulate the number of DLM fibers generated. Thus, while the persistent larval muscle fibers are not obligatory for DLM fiber formation and differentiation, they are necessary to ensure the development of the correct number of fibers.

  15. A contrastive-stylistic study into the tense distribution in English and Slovene fictional texts

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    Silvana Orel Kos

    2008-12-01

    Full Text Available The article addresses contrastive and narratological issues of the unity vs. diversity of temporal spheres in fictional texts. It focuses on the presentation of mimetic discourse within the past time-sphere narrative, trying to establish the narrative or stylistic functions of the present and past time-sphere verb actions with respect to the role of the narrator or that of the character. the diegetic and mimetic functions of verb actions in certain temporal spheres, ie. tense usage in (free indirect discourse (free direct discourse, will be contrastively studied in original fictional texts and their translations, in both directions between english and Slovene. the character’s mimetic discourse may be presented through different narrative forms, spanning the report-control cline from the forms “in total control” of the character, ie. free direct discourse, to that “apparently in total control” of the narrator, ie. speech act and thought act report (cf. Leech and Short 1981: 324. in addition to the character’s verbal and mental responses, the study includes mediated instances of the character’s sensory responses, the basic formula thus being: He said that/thought that/saw that. Our contrastive analysis considers only fictional texts whose diegesis is rendered   in the narrative past tenses, as the english language system observes the sequence of tenses, while the Slovene language does not. the diegesis of a fictional text may be completely located in the present time-sphere, yet such texts do not present any major issues in terms of contrastive relevance for the studied language pair.

  16. The making of indigenous vascular prosthesis

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    Madathipat Unnikrishnan

    2016-01-01

    Full Text Available Background & objectives: Vascular illnesses are on the rise in India, due to increase in lifestyle diseases and demographic transition, requiring intervention to save life, organ or limbs using vascular prosthesis. The aim of this study was to develop indigenous large diameter vascular graft for treatment of patients with vascular pathologies. Methods: The South India Textile Research Association, at Coimbatore, Tamil Nadu, India, developed seamless woven polyester (Polyethylene terephthalate graft at its research wing. Further characterization and testing followed by clinical trials were conducted at Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, Kerala, India. Fifteen in vivo experiments were carried out in 1992-1994 in pigs as animal model. Controlled (phase I clinical trial in ten patients was performed along with control graft. Thereafter, phase II trial involved 22 patients who underwent multi-centre clinical trial in four centres across India. Results: Laboratory testing showed that polyester graft was non-toxic, non-leeching and non-haemolytic with preserved long-term quality, further confirming in pigs by implanting in thoracic aorta, comparable to control Dacron grafts. Perigraft incorporation and smooth neointima formation which are prime features of excellent healing characteristics, were noted at explantation at planned intervals. Subsequently in the phase I and II clinical trials, all patients had excellent recovery without mortality or device-related adverse events. Patients receiving the test graft were followed up for 10 and 5 years, respectively. Serial clinical, duplex scans and CT angiograms performed periodically confirmed excellent graft performance. Interpretation & conclusions: Indigenously developed Chitra vascular graft was comparable to commercially available Dacron graft, ready for clinical use at affordable cost to patients as against costly imported grafts.

  17. Parasites of native and nonnative fishes of the Little Colorado River, Grand Canyon, Arizona

    Science.gov (United States)

    Choudhury, A.; Hoffnagle, T.L.; Cole, Rebecca A.

    2004-01-01

    A 2-yr, seasonal, parasitological study of 1,435 fish, belonging to 4 species of native fishes and 7 species of nonnative fishes from the lower Little Colorado River (LCR) and tributary creeks, Grand Canyon, Arizona, yielded 17 species of parasites. These comprised 1 myxozoan (Henneguya exilis), 2 copepods (Ergasilus arthrosis and Lernaea cyprinacea), 1 acarine (Oribatida gen. sp.), 1 piscicolid leech (Myzobdella lugubris), 4 monogeneans (Gyrodactylus hoffmani, Gyrodactylus sp., Dactylogyrus extensus, and Ligictaluridus floridanus), 4 nematodes (Contracaecum sp., Eustrongylides sp., Rhabdochona sp., and Truttaedacnitis truttae), 3 cestodes (Bothriocephalus acheilognathi, Corallobothrium fimbriatum, and Megathylacoides giganteum), and 2 trematodes (Ornithodiplostomum sp. and Posthodiplostomum sp.). Rhabdochona sp. was the only adult parasite native to the LCR. Infection intensities of Ornithodiplostomum sp. and B. acheilognathi were positively correlated with length of the humpback chub Gila cypha. Adult helminths showed a high degree of host specificity, except B. acheilognathi, which was recovered from all fish species examined but was most abundant in cyprinids. Abundance of B. acheilognathi in the humpback chub was highest in the fall and lowest in the summer in both reaches of the LCR. There was no major taxonomic difference in parasite assemblages between the 2 different reaches of the river (LC1 and LC2). Parasite community diversity was very similar in humpback chub, regardless of sampling site or time. The parasite fauna of the LCR is numerically dominated by B. acheilognathi and metacercariae of Ornithodiplostomum sp. The richest and most diverse component community occurred in a nonnative species, the channel catfish Ictalurus punctatus, but infracommunity species richness was highest in a native host, humpback chub.

  18. Phylogenetic utility of ribosomal genes for reconstructing the phylogeny of five Chinese satyrine tribes (Lepidoptera, Nymphalidae

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    Mingsheng Yang

    2015-03-01

    Full Text Available Satyrinae is one of twelve subfamilies of the butterfly family Nymphalidae, which currently includes nine tribes. However, phylogenetic relationships among them remain largely unresolved, though different researches have been conducted based on both morphological and molecular data. However, ribosomal genes have never been used in tribe level phylogenetic analyses of Satyrinae. In this study we investigate for the first time the phylogenetic relationships among the tribes Elymniini, Amathusiini, Zetherini and Melanitini which are indicated to be a monophyletic group, and the Satyrini, using two ribosomal genes (28s rDNA and 16s rDNA and four protein-coding genes (EF-1α, COI, COII and Cytb. We mainly aim to assess the phylogenetic informativeness of the ribosomal genes as well as clarify the relationships among different tribes. Our results show the two ribosomal genes generally have the same high phylogenetic informativeness compared with EF-1α; and we infer the 28s rDNA would show better informativeness if the 28s rDNA sequence data for each sampling taxon are obtained in this study. The placement of the monotypic genus Callarge Leech in Zetherini is confirmed for the first time based on molecular evidence. In addition, our maximum likelihood (ML and Bayesian inference (BI trees consistently show that the involved Satyrinae including the Amathusiini is monophyletic with high support values. Although the relationships among the five tribes are identical among ML and BI analyses and are mostly strongly-supported in BI analysis, those in ML analysis are lowly- or moderately- supported. Therefore, the relationships among the related five tribes recovered herein need further verification based on more sampling taxa.

  19. Reconstruction of circulation in the fingertip without vein repair in zone I replantation.

    Science.gov (United States)

    Zhang, Xu; Wen, Sumin; Wang, Baoshi; Wang, Qi; Li, Chenglin; Zhu, Hongwei

    2008-11-01

    In fingertip replantation, adequate venous drainage is important for success. As the level of amputation becomes more distal, anastomosis of veins becomes more technically difficult. External bleeding is a common solution to venous congestion, but the process is burdensome because of duration of bleeding for 3 or more days after surgery. We present a new technique for reconstructing circulation without vein anastomosis in zone I replantation and analyze the outcomes of this technique in terms of eliminating external bleeding and of a high survival rate of the replanted digits. Between 1997 and 2007, we performed 120 replantations in 112 patients (83 male and 29 female; mean age, 33 years; range, 3-54 years). All were zone I amputations, based on the Tamai classification. We surgically repaired both proper digital arteries, excluded the vein, and then ligated 1 of the arteries. Using this technique, circulation was restored. Included in the outcome evaluation were 91 digits in the 87 patients (mean age, 35 years; range, 14-54) who returned for outcome assessments 12 months after surgery. Of 120 digits replanted, 115 digits survived, corresponding to an overall success rate of 96%. No patients received alternative means to alleviate venous congestion, such as leeches or other means of external bleeding. Nearly all of the 87 patients (91 digits) were satisfied with the results of the replantations. Our technique reconstructs circulation without vein anastomosis in zone I replantation. This alternative to venous congestion involves a simple surgical procedure and straightforward postoperative care. Follow-up assessments of a series of 120 replantations show that the majority of zone I replantations led to satisfactory function. We therefore propose this technique as an effective method for zone I replantation. Therapeutic IV.

  20. Nonarterialized Venous Replantation of Part of Amputated Thumb—A Case Report and Review of the Literature

    Science.gov (United States)

    Kalimuthu, Ramasamy

    2006-01-01

    Since the first successful replantation of a human thumb reported by Komatsu and Tamai in 1968, thousands of severed digits and body parts have been successfully salvaged. Restoration of anatomic form and function are the goals of replantation after traumatic tissue amputation. Regardless of anatomic location, methods include microsurgical replantation and nonmicrosurgical replantation, such as composite graft techniques. Numerous techniques to maximize tissue survival after revascularization have been described, including “pocket procedures” to salvage composite grafts, interposition vein grafts, and medicinal leeches to name a few. Artery-to-venous anastomoses have been performed with successful “arterialization” of the distal venous system in fingertip replantation. Although there is documented survival of free venous cutaneous flaps, to our knowledge this is the first report of a replanted composite body part (bone, tendon, soft tissues, and skin) utilizing exclusively multiple, microvascular, nonarterialized venous–venous anastomoses. We present a patient with an isolated band saw fillet amputation to the back of the thumb at the metacarpal–phalangeal joint region, resulting in a composite graft composed of bone, tendon, soft tissue, and skin. The hand wound provided no viable regional arterial inflow source, but there were multiple good caliber superficial veins present. The amputated tissues were replanted and revascularized by using only venous blood flow. The replanted part survival was 100% with excellent function of the digit. We conclude that a hand composite body part involving bone, tendon, soft tissues, and skin can survive replantation with a strict venous blood supply if sufficient good caliber, microvascular, venous–venous anastomoses are performed, granted that arterial inflow options are not available. This is an isolated case, yet introduces a new way of thinking regarding tissue replantation. PMID:18780032

  1. A nonadaptive origin of a beneficial trait: in silico selection for free energy of folding leads to the neutral emergence of mutational robustness in single domain proteins.

    Science.gov (United States)

    Pagan, Rafael F; Massey, Steven E

    2014-02-01

    Proteins are regarded as being robust to the deleterious effects of mutations. Here, the neutral emergence of mutational robustness in a population of single domain proteins is explored using computer simulations. A pairwise contact model was used to calculate the ΔG of folding (ΔG folding) using the three dimensional protein structure of leech eglin C. A random amino acid sequence with low mutational robustness, defined as the average ΔΔG resulting from a point mutation (ΔΔG average), was threaded onto the structure. A population of 1,000 threaded sequences was evolved under selection for stability, using an upper and lower energy threshold. Under these conditions, mutational robustness increased over time in the most common sequence in the population. In contrast, when the wild type sequence was used it did not show an increase in robustness. This implies that the emergence of mutational robustness is sequence specific and that wild type sequences may be close to maximal robustness. In addition, an inverse relationship between ∆∆G average and protein stability is shown, resulting partly from a larger average effect of point mutations in more stable proteins. The emergence of mutational robustness was also observed in the Escherichia coli colE1 Rop and human CD59 proteins, implying that the property may be common in single domain proteins under certain simulation conditions. The results indicate that at least a portion of mutational robustness in small globular proteins might have arisen by a process of neutral emergence, and could be an example of a beneficial trait that has not been directly selected for, termed a "pseudaptation."

  2. Developing neurons use a putative pioneer's peripheral arbor to establish their terminal fields.

    Science.gov (United States)

    Gan, W B; Macagno, E R

    1995-05-01

    Pioneer neurons are known to guide later developing neurons during the initial phases of axonal outgrowth. To determine whether they are also important in the formation of terminal fields by the follower cells, we studied the role of a putative leech pioneer neuron, the pressure-sensitive (PD) neuron, in the establishment of other neurons' peripheral arbors. The PD neuron has a major axon that exits from its segmental ganglion to grow along the dorsal-posterior (DP) nerve to the dorsal body wall, where it arborizes extensively mainly in its own segment. It also has two minor axons that project to the two adjacent segments but branch to a lesser degree. We found that the peripheral projections of several later developing neurons, including the AP motor neuron and the TD sensory neuron, followed, with great precision, the major axon and peripheral arbor of the consegmental PD neuron, up to its fourth-order branches. When a PD neuron was ablated before it had grown to the body wall, the AP and TD axons grew normally toward and reached the target area, but then formed terminal arbors that were greatly reduced in size and abnormal in morphology. Further, if the ablation of a PD neuron was accompanied by the induction, in the same segment, of greater outgrowth of the minor axon of a PD neuron from the adjacent segment, the arbors of the same AP neurons grew along these novel PD neuron branches. These results demonstrate that the peripheral arbor of a PD neuron is a both necessary and sufficient template for the formation of normal terminal fields by certain later growing follower neurons.

  3. A (FORENSIC STYLISTIC ANALYSIS OF ADVERBIALS OF ATTITUDE AND EMPHASIS IN SUPREME COURT DECISIONS IN PHILIPPINE ENGLISH

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    Hjalmar Punla Hernandez

    2017-09-01

    Full Text Available Contemporarily, stylistics today has developed into its multiplicity – one of which is forensic stylistics. Being a powerfully legal written discourse, Supreme Court decisions are a rich corpus in which linguistic vis-a-vis stylistic choices of Court justices could be examined. This study is a humble attempt at stylistically analyzing Supreme Court decisions in Philippine English (PhE drafted by two Filipino justices. Specifically, it sought to investigate on the classes, placements, and environments of adverbials of attitude and emphasis employed by the two justices, and drew their implications to teaching and learning English for Legal Purposes (ELP. Using McMenamin (2012, Quirk, Greenbaum, Leech, and Svartvik (1985, and Dita’s (2011 frameworks, 54 randomly selected Supreme Court decisions as primary sources of legal language were analyzed. Results are the following. Firstly, the classes of adverbials of attitude in Supreme Court decisions in PhE used by the two judges were the evaluation to the subject of the clause, judgment to the whole clause, and evaluation to an action performed by the subject of the clause, while those adverbials of emphasis were adverbials of conviction and doubt. Secondly, both adverbials they used have placements that were frequently medial and less initial in sentences where they belonged. Thirdly, the two justices put their adverbials within two principal environments, i.e. within functor, and before/after the verb among others. In these regards, legal and stylistic explanations with respect to these recurrent linguistic features in the two justices’ Court decisions were revealed. Implications of the study to ELP are explained. Lastly, trajectories for future (forensic stylistic analyses have been recommended.

  4. Attenuation in the dubbing and subtitling of The Green Mile

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    Lidia Rodríguez

    2015-12-01

    Full Text Available This paper is part of the doctoral thesis entitled “Critique of translation for film dubbing and subtitling from the perspective of discourse analysis. A study applied to "The Green Mile”, written by Ph.D. student Gabriela Saturnina Alanís Uresti, directed by Ph.D. Lidia Rodríguez. It is a qualitative and descriptive study where we contrasted The Green Mile - a 1999 Hollywood film, original in American English - with its translated versions: dubbed and subtitled into Spanish of Mexico. We start from the presupposition that in film translation, some references such as the ones related to sexual behaviors and offensive language are attenuated in order to be strategically polite. Specifically, we analyzed two mechanisms of attenuation: lexical selection whereby a euphemism is used, and discursive modalization. These mechanisms constitute strategies of linguistic, pragmatic and semiotic nature as they appear in original (OV, dubbed (DV and subtitled (SV versions; both in acoustic and visual channels. Therefore, we examine these occurrences on verbal, para-verbal, and non-verbal codes. The theoretical basis includes studies of attenuation, politeness, euphemisms, and linguistic taboos. This paper is based on methodological proposals by Gutiérrez (2008, Nájar (2009, Brown y Levinson (1987, Goffman (1967, Leech (1983, Fraser (1980 Haverkate (1994, Bravo (2001, Albelda (2010, (2005, Albelda y Briz (2010, Briz (2002a; 2002b, Allan y Burridge (2006, Chamizo (2008, Foucault (1987, Seiciuc (2010, Dubois (1969, Dubois et al (1973, and Rodríguez (2004.

  5. The effect of pH on chronic aquatic nickel toxicity is dependent on the pH itself: Extending the chronic nickel bioavailability models.

    Science.gov (United States)

    Nys, Charlotte; Janssen, Colin R; Van Sprang, Patrick; De Schamphelaere, Karel A C

    2016-05-01

    The environmental quality standard for Ni in the European Commission's Water Framework Directive is bioavailability based. Although some of the available chronic Ni bioavailability models are validated only for pH ≤ 8.2, a considerable fraction of European surface waters has a pH > 8.2. Therefore, the authors investigated the effect of a change in pH from 8.2 to 8.7 on chronic Ni toxicity in 3 invertebrate (Daphnia magna, Lymnaea stagnalis, and Brachionus calyciflorus) and 2 plant species (Pseudokirchneriella subcapitata and Lemna minor). Nickel toxicity was almost always significantly higher at pH 8.7 than at pH 8.2. To test whether the existing chronic Ni bioavailability models developed for pH ≤ 8.2 can be used at higher pH levels, Ni toxicity at pH 8.7 was predicted based on Ni toxicity observed at pH 8.2. This resulted in a consistent underestimation of toxicity. The results suggest that the effect of pH on Ni(2+) toxicity is dependent on the pH itself: the slope of the pH effect is steeper above than below pH 8.2 for species for which a species-specific bioavailability model exists. Therefore, the existing chronic Ni bioavailability models were modified to allow predictions of chronic Ni toxicity to invertebrates and plants in the pH range of 8.2 to 8.7 by applying a pH slope (SpH ) dependent on the pH of the target water. These modified Ni bioavailability models resulted in more accurate predictions of Ni toxicity to all 5 species (within 2-fold error), without the bias observed using the bioavailability models developed for pH ≤ 8.2. The results of the present study can decrease the uncertainty in implementing the bioavailability-based environmental quality standard under the Water Framework Directive for high-pH regions in Europe. © 2015 SETAC.

  6. Memory trace in feeding neural circuitry underlying conditioned taste aversion in Lymnaea.

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    Etsuro Ito

    Full Text Available BACKGROUND: The pond snail Lymnaea stagnalis can maintain a conditioned taste aversion (CTA as a long-term memory. Previous studies have shown that the inhibitory postsynaptic potential (IPSP evoked in the neuron 1 medial (N1M cell by activation of the cerebral giant cell (CGC in taste aversion-trained snails was larger and lasted longer than that in control snails. The N1M cell is one of the interneurons in the feeding central pattern generator (CPG, and the CGC is a key regulatory neuron for the feeding CPG. METHODOLOGY/PRINCIPLE FINDINGS: Previous studies have suggested that the neural circuit between the CGC and the N1M cell consists of two synaptic connections: (1 the excitatory connection from the CGC to the neuron 3 tonic (N3t cell and (2 the inhibitory connection from the N3t cell to the N1M cell. However, because the N3t cell is too small to access consistently by electrophysiological methods, in the present study the synaptic inputs from the CGC to the N3t cell and those from the N3t cell to the N1M cell were monitored as the monosynaptic excitatory postsynaptic potential (EPSP recorded in the large B1 and B3 motor neurons, respectively. The evoked monosynaptic EPSPs of the B1 motor neurons in the brains isolated from the taste aversion-trained snails were identical to those in the control snails, whereas the spontaneous monosynaptic EPSPs of the B3 motor neurons were significantly enlarged. CONCLUSION/SIGNIFICANCE: These results suggest that, after taste aversion training, the monosynaptic inputs from the N3t cell to the following neurons including the N1M cell are specifically facilitated. That is, one of the memory traces for taste aversion remains as an increase in neurotransmitter released from the N3t cell. We thus conclude that the N3t cell suppresses the N1M cell in the feeding CPG, in response to the conditioned stimulus in Lymnaea CTA.

  7. Memory trace in feeding neural circuitry underlying conditioned taste aversion in Lymnaea.

    Science.gov (United States)

    Ito, Etsuro; Otsuka, Emi; Hama, Noriyuki; Aonuma, Hitoshi; Okada, Ryuichi; Hatakeyama, Dai; Fujito, Yutaka; Kobayashi, Suguru

    2012-01-01

    The pond snail Lymnaea stagnalis can maintain a conditioned taste aversion (CTA) as a long-term memory. Previous studies have shown that the inhibitory postsynaptic potential (IPSP) evoked in the neuron 1 medial (N1M) cell by activation of the cerebral giant cell (CGC) in taste aversion-trained snails was larger and lasted longer than that in control snails. The N1M cell is one of the interneurons in the feeding central pattern generator (CPG), and the CGC is a key regulatory neuron for the feeding CPG. Previous studies have suggested that the neural circuit between the CGC and the N1M cell consists of two synaptic connections: (1) the excitatory connection from the CGC to the neuron 3 tonic (N3t) cell and (2) the inhibitory connection from the N3t cell to the N1M cell. However, because the N3t cell is too small to access consistently by electrophysiological methods, in the present study the synaptic inputs from the CGC to the N3t cell and those from the N3t cell to the N1M cell were monitored as the monosynaptic excitatory postsynaptic potential (EPSP) recorded in the large B1 and B3 motor neurons, respectively. The evoked monosynaptic EPSPs of the B1 motor neurons in the brains isolated from the taste aversion-trained snails were identical to those in the control snails, whereas the spontaneous monosynaptic EPSPs of the B3 motor neurons were significantly enlarged. These results suggest that, after taste aversion training, the monosynaptic inputs from the N3t cell to the following neurons including the N1M cell are specifically facilitated. That is, one of the memory traces for taste aversion remains as an increase in neurotransmitter released from the N3t cell. We thus conclude that the N3t cell suppresses the N1M cell in the feeding CPG, in response to the conditioned stimulus in Lymnaea CTA.

  8. Pancreatic and snake venom presynaptically active phospholipases A2 inhibit nicotinic acetylcholine receptors.

    Science.gov (United States)

    Vulfius, Catherine A; Kasheverov, Igor E; Kryukova, Elena V; Spirova, Ekaterina N; Shelukhina, Irina V; Starkov, Vladislav G; Andreeva, Tatyana V; Faure, Grazyna; Zouridakis, Marios; Tsetlin, Victor I; Utkin, Yuri N

    2017-01-01

    Phospholipases A2 (PLA2s) are enzymes found throughout the animal kingdom. They hydrolyze phospholipids in the sn-2 position producing lysophospholipids and unsaturated fatty acids, agents that can damage membranes. PLA2s from snake venoms have numerous toxic effects, not all of which can be explained by phospholipid hydrolysis, and each enzyme has a specific effect. We have earlier demonstrated the capability of several snake venom PLA2s with different enzymatic, cytotoxic, anticoagulant and antiproliferative properties, to decrease acetylcholine-induced currents in Lymnaea stagnalis neurons, and to compete with α-bungarotoxin for binding to nicotinic acetylcholine receptors (nAChRs) and acetylcholine binding protein. Since nAChRs are implicated in postsynaptic and presynaptic activities, in this work we probe those PLA2s known to have strong presynaptic effects, namely β-bungarotoxin from Bungarus multicinctus and crotoxin from Crotalus durissus terrificus. We also wished to explore whether mammalian PLA2s interact with nAChRs, and have examined non-toxic PLA2 from porcine pancreas. It was found that porcine pancreatic PLA2 and presynaptic β-bungarotoxin blocked currents mediated by nAChRs in Lymnaea neurons with IC50s of 2.5 and 4.8 μM, respectively. Crotoxin competed with radioactive α-bungarotoxin for binding to Torpedo and human α7 nAChRs and to the acetylcholine binding protein. Pancreatic PLA2 interacted similarly with these targets; moreover, it inhibited radioactive α-bungarotoxin binding to the water-soluble extracellular domain of human α9 nAChR, and blocked acetylcholine induced currents in human α9α10 nAChRs heterologously expressed in Xenopus oocytes. These and our earlier results show that all snake PLA2s, including presynaptically active crotoxin and β-bungarotoxin, as well as mammalian pancreatic PLA2, interact with nAChRs. The data obtained suggest that this interaction may be a general property of all PLA2s, which should be proved by

  9. Failure of delayed nonsynaptic neuronal plasticity underlies age-associated long-term associative memory impairment

    Directory of Open Access Journals (Sweden)

    Watson Shawn N

    2012-08-01

    Full Text Available Abstract Background Cognitive impairment associated with subtle changes in neuron and neuronal network function rather than widespread neuron death is a feature of the normal aging process in humans and animals. Despite its broad evolutionary conservation, the etiology of this aging process is not well understood. However, recent evidence suggests the existence of a link between oxidative stress in the form of progressive membrane lipid peroxidation, declining neuronal electrical excitability and functional decline of the normal aging brain. The current study applies a combination of behavioural and electrophysiological techniques and pharmacological interventions to explore this hypothesis in a gastropod model (Lymnaea stagnalis feeding system that allows pinpointing the molecular and neurobiological foundations of age-associated long-term memory (LTM failure at the level of individual identified neurons and synapses. Results Classical appetitive reward-conditioning induced robust LTM in mature animals in the first quartile of their lifespan but failed to do so in animals in the last quartile of their lifespan. LTM failure correlated with reduced electrical excitability of two identified serotonergic modulatory interneurons (CGCs critical in chemosensory integration by the neural network controlling feeding behaviour. Moreover, while behavioural conditioning induced delayed-onset persistent depolarization of the CGCs known to underlie appetitive LTM formation in this model in the younger animals, it failed to do so in LTM-deficient senescent animals. Dietary supplementation of the lipophilic anti-oxidant α-tocopherol reversed the effect of age on CGCs electrophysiological characteristics but failed to restore appetitive LTM function. Treatment with the SSRI fluoxetine reversed both the neurophysiological and behavioural effects of age in senior animals. Conclusions The results identify the CGCs as cellular loci of age-associated appetitive

  10. Radiation-induced cytogenetic and hematologic effects on aquatic biota within the Chernobyl exclusion zone.

    Science.gov (United States)

    Gudkov, D I; Shevtsova, N L; Pomortseva, N A; Dzyubenko, E V; Kaglyan, A E; Nazarov, A B

    2016-01-01

    During 1998-2014 the rate of chromosomal aberrations in embryo tissues of the pond snail (Lymnaea stagnalis) and root meristems of higher aquatic plants, and also hematologic indexes of mantle liquid of the adult snails and peripheral blood of fishes in water bodies within the Chernobyl exclusion zone (EZ) was studied. The absorbed dose rate for hydrobionts from water bodies of the EZ registered in a range from 0.25 to 420 μGy h(-1) and in the reference ones - up to 0.09 μGy h(-1). The level of chromosomal aberrations in the molluscs from the most contaminated water bodies of the EZ was registered within range of 18-27% and for the molluscs from the reference lakes this index was on the average 1.5% with the maximal values 2.3%. The rate of chromosomal aberrations in root meristematic cells of higher aquatic plants from the contaminated lakes of the EZ was in range of 7-17% and in the plants from reference water bodies was not exceed 2.1%. The positive correlation between chromosomal aberration rate and absorbed dose rate in the pond snail's embryos and root meristems of higher aquatic plants in water bodies of the EZ was registered. Analysis of hemolymph structure of snails from the most contaminated water bodies showed a high rate of dead and phagocytic cells as well as decrease of the young amoebocytes quantity. Hematologic research of fish allows to determine on the one hand an insignificant changes of leukogram structure, and from the other hand a high level of red cells with different abnormalities in the peripheral blood of fishes from the water bodies with high levels of radioactive contamination. It is suppose that qualitative indexes of red cells in peripheral blood of fish are more sensitive to long-term radiation impact in comparison with elements of white blood, which can be used for conducting of the hematologic monitoring of radioactive contaminated water bodies. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. The chronic toxicity of molybdate to freshwater organisms. I. Generating reliable effects data

    Energy Technology Data Exchange (ETDEWEB)

    De Schamphelaere, K.A.C., E-mail: karel.deschamphelaere@Ugent.be [Laboratory of Environmental Toxicology and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University (Belgium); Stubblefield, W. [Oregon State University, Department of Environmental and Molecular Toxicology, 421 Weniger Hall, Corvallis, OR 97331 (United States); Rodriguez, P. [Centro de Investigacion Minera y Metalurgica (CIMM), Santiago (Chile); Vleminckx, K. [Department for Molecular Biomedical Research, Ghent University (Belgium); Janssen, C.R. [Laboratory of Environmental Toxicology and Aquatic Ecology, Faculty of Bioscience Engineering, Ghent University (Belgium)

    2010-10-15

    The European Union regulation on Registration, Evaluation, Authorization and Restriction of Chemical substances (REACH) (EC, 2006) requires the characterization of the chronic toxicity of many chemicals in the aquatic environment, including molybdate (MoO{sub 4}{sup 2-}). Our literature review on the ecotoxicity of molybdate revealed that a limited amount of reliable chronic no observed effect concentrations (NOECs) for the derivation of a predicted no-effect concentration (PNEC) existed. This paper presents the results of additional ecotoxicity experiments that were conducted in order to fulfill the requirements for the derivation of a PNEC by means of the scientifically most robust species sensitivity distribution (SSD) approach (also called the statistical extrapolation approach). Ten test species were chronically exposed to molybdate (added as sodium molybdate dihydrate, Na{sub 2}MoO{sub 4}.2H{sub 2}O) according to internationally accepted standard testing guidelines or equivalent. The 10% effective concentrations (EC10, expressed as measured dissolved molybdenum) for the most sensitive endpoint per species were 62.8-105.6 (mg Mo)/L for Daphnia magna (21 day-reproduction), 78.2 (mg Mo)/L for Ceriodaphnia dubia (7 day-reproduction), 61.2-366.2 (mg Mo)/L for the green alga Pseudokirchneriella subcapitata (72 h-growth rate), 193.6 (mg Mo)/L for the rotifer Brachionus calyciflorus (48 h-population growth rate), 121.4 (mg Mo)/L for the midge Chironomus riparius (14 day-growth), 211.3 (mg Mo)/L for the snail Lymnaea stagnalis (28 day-growth rate), 115.9 (mg Mo)/L for the frog Xenopus laevis (4 day-larval development), 241.5 (mg Mo)/L for the higher plant Lemna minor (7 day-growth rate), 39.3 (mg Mo)/L for the fathead minnow Pimephales promelas (34 day-dry weight/biomass), and 43.2 (mg Mo)/L for the rainbow trout Oncorhynchus mykiss (78 day-biomass). These effect concentrations are in line with the few reliable data currently available in the open literature. The data

  12. The chronic toxicity of molybdate to freshwater organisms. I. Generating reliable effects data

    International Nuclear Information System (INIS)

    De Schamphelaere, K.A.C.; Stubblefield, W.; Rodriguez, P.; Vleminckx, K.; Janssen, C.R.

    2010-01-01

    The European Union regulation on Registration, Evaluation, Authorization and Restriction of Chemical substances (REACH) (EC, 2006) requires the characterization of the chronic toxicity of many chemicals in the aquatic environment, including molybdate (MoO 4 2- ). Our literature review on the ecotoxicity of molybdate revealed that a limited amount of reliable chronic no observed effect concentrations (NOECs) for the derivation of a predicted no-effect concentration (PNEC) existed. This paper presents the results of additional ecotoxicity experiments that were conducted in order to fulfill the requirements for the derivation of a PNEC by means of the scientifically most robust species sensitivity distribution (SSD) approach (also called the statistical extrapolation approach). Ten test species were chronically exposed to molybdate (added as sodium molybdate dihydrate, Na 2 MoO 4 .2H 2 O) according to internationally accepted standard testing guidelines or equivalent. The 10% effective concentrations (EC10, expressed as measured dissolved molybdenum) for the most sensitive endpoint per species were 62.8-105.6 (mg Mo)/L for Daphnia magna (21 day-reproduction), 78.2 (mg Mo)/L for Ceriodaphnia dubia (7 day-reproduction), 61.2-366.2 (mg Mo)/L for the green alga Pseudokirchneriella subcapitata (72 h-growth rate), 193.6 (mg Mo)/L for the rotifer Brachionus calyciflorus (48 h-population growth rate), 121.4 (mg Mo)/L for the midge Chironomus riparius (14 day-growth), 211.3 (mg Mo)/L for the snail Lymnaea stagnalis (28 day-growth rate), 115.9 (mg Mo)/L for the frog Xenopus laevis (4 day-larval development), 241.5 (mg Mo)/L for the higher plant Lemna minor (7 day-growth rate), 39.3 (mg Mo)/L for the fathead minnow Pimephales promelas (34 day-dry weight/biomass), and 43.2 (mg Mo)/L for the rainbow trout Oncorhynchus mykiss (78 day-biomass). These effect concentrations are in line with the few reliable data currently available in the open literature. The data presented in this

  13. Pancreatic and snake venom presynaptically active phospholipases A2 inhibit nicotinic acetylcholine receptors.

    Directory of Open Access Journals (Sweden)

    Catherine A Vulfius

    Full Text Available Phospholipases A2 (PLA2s are enzymes found throughout the animal kingdom. They hydrolyze phospholipids in the sn-2 position producing lysophospholipids and unsaturated fatty acids, agents that can damage membranes. PLA2s from snake venoms have numerous toxic effects, not all of which can be explained by phospholipid hydrolysis, and each enzyme has a specific effect. We have earlier demonstrated the capability of several snake venom PLA2s with different enzymatic, cytotoxic, anticoagulant and antiproliferative properties, to decrease acetylcholine-induced currents in Lymnaea stagnalis neurons, and to compete with α-bungarotoxin for binding to nicotinic acetylcholine receptors (nAChRs and acetylcholine binding protein. Since nAChRs are implicated in postsynaptic and presynaptic activities, in this work we probe those PLA2s known to have strong presynaptic effects, namely β-bungarotoxin from Bungarus multicinctus and crotoxin from Crotalus durissus terrificus. We also wished to explore whether mammalian PLA2s interact with nAChRs, and have examined non-toxic PLA2 from porcine pancreas. It was found that porcine pancreatic PLA2 and presynaptic β-bungarotoxin blocked currents mediated by nAChRs in Lymnaea neurons with IC50s of 2.5 and 4.8 μM, respectively. Crotoxin competed with radioactive α-bungarotoxin for binding to Torpedo and human α7 nAChRs and to the acetylcholine binding protein. Pancreatic PLA2 interacted similarly with these targets; moreover, it inhibited radioactive α-bungarotoxin binding to the water-soluble extracellular domain of human α9 nAChR, and blocked acetylcholine induced currents in human α9α10 nAChRs heterologously expressed in Xenopus oocytes. These and our earlier results show that all snake PLA2s, including presynaptically active crotoxin and β-bungarotoxin, as well as mammalian pancreatic PLA2, interact with nAChRs. The data obtained suggest that this interaction may be a general property of all PLA2s, which

  14. Quantitative modeling of responses to chronic ionizing radiation exposure using targeted and non-targeted effects.

    Directory of Open Access Journals (Sweden)

    Igor Shuryak

    Full Text Available The biological effects of chronic ionizing radiation exposure can be difficult to study, but important to understand in order to protect the health of occupationally-exposed persons and victims of radiological accidents or malicious events. They include targeted effects (TE caused by ionizations within/close to nuclear DNA, and non-targeted effects (NTE caused by damage to other cell structures and/or activation of stress-signaling pathways in distant cells. Data on radiation damage in animal populations exposed over multiple generations to wide ranges of dose rates after the Chernobyl nuclear-power-plant accident are very useful for enhancing our understanding of these processes. We used a mechanistically-motivated mathematical model which includes TE and NTE to analyze a large published data set on chromosomal aberrations in pond snail (Lymnaea stagnalis embryos collected over 16 years from water bodies contaminated by Chernobyl fallout, and from control locations. The fraction of embryo cells with aberrations increased dramatically (>10-fold and non-linearly over a dose rate range of 0.03-420 μGy/h (0.00026-3.7 Gy/year. NTE were very important for describing the non-linearity of this radiation response: the TE-only model (without NTE performed dramatically worse than the TE+NTE model. NTE were predicted to reach ½ of maximal intensity at 2.5 μGy/h (0.022 Gy/year and to contribute >90% to the radiation response slope at dose rates <11 μGy/h (0.1 Gy/year. Internally-incorporated 90Sr was possibly more effective per unit dose than other radionuclides. The radiation response shape for chromosomal aberrations in snail embryos was consistent with data for a different endpoint: the fraction of young amoebocytes in adult snail haemolymph. Therefore, radiation may affect different snail life stages by similar mechanisms. The importance of NTE in our model-based analysis suggests that the search for modulators of NTE-related signaling pathways

  15. Bioanalytical Applications of Real-Time ATP Imaging Via Bioluminescence

    Energy Technology Data Exchange (ETDEWEB)

    Gruenhagen, Jason Alan [Iowa State Univ., Ames, IA (United States)

    2003-01-01

    The research discussed within involves the development of novel applications of real-time imaging of adenosine 5'-triphosphate (ATP). ATP was detected via bioluminescence and the firefly luciferase-catalyzed reaction of ATP and luciferin. The use of a microscope and an imaging detector allowed for spatially resolved quantitation of ATP release. Employing this method, applications in both biological and chemical systems were developed. First, the mechanism by which the compound 48/80 induces release of ATP from human umbilical vein endothelial cells (HUVECs) was investigated. Numerous enzyme activators and inhibitors were utilized to probe the second messenger systems involved in release. Compound 48/80 activated a G{sub q}-type protein to initiate ATP release from HUVECs. Ca2+ imaging along with ATP imaging revealed that activation of phospholipase C and induction of intracellular Ca2+ signaling were necessary for release of ATP. Furthermore, activation of protein kinase C inhibited the activity of phospholipase C and thus decreased the magnitude of ATP release. This novel release mechanism was compared to the existing theories of extracellular release of ATP. Bioluminescence imaging was also employed to examine the role of ATP in the field of neuroscience. The central nervous system (CNS) was dissected from the freshwater snail Lymnaea stagnalis. Electrophysiological experiments demonstrated that the neurons of the Lymnaea were not damaged by any of the components of the imaging solution. ATP was continuously released by the ganglia of the CNS for over eight hours and varied from ganglion to ganglion and within individual ganglia. Addition of the neurotransmitters K+ and serotonin increased release of ATP in certain regions of the Lymnaea CNS. Finally, the ATP imaging technique was investigated for the study of drug release systems. MCM-41-type mesoporous nanospheres were loaded with ATP and end-capped with mercaptoethanol

  16. Influence of therapeutic radiation on polycaprolactone and polyurethane biomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Cooke, Shelley L. [Department of Materials Science and Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 (United States); Whittington, Abby R., E-mail: awhit@mse.vt.edu [Department of Materials Science and Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 (United States); Department of Chemical Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 (United States)

    2016-03-01

    ABSTRACT: Biomedical polymers are exposed in vivo to ionizing radiation as implants, coatings and bystander materials. High levels of ionizing radiation (e.g. X-ray and gamma) have been reported to cause degradation and/or cross-linking in many polymers. This pilot study sought to determine causes of failure, by investigating how therapeutic radiation affects two different porous polymeric scaffolds: polycaprolactone (PCL) and polyurethane (PU). PCL is a bioresorbable material used in biomedical devices (e.g., dentistry, internal fixation devices and targeted drug delivery capsules). PU is commonly used in medical applications (e.g., coatings for pacemakers, tissue expanders, catheter tubing and wound dressings). PU was specifically fabricated to be a non-degradable polymer in this study. Porous scaffolds, fabricated using solvent casting and/or salt leeching techniques, were placed in phosphate buffered saline (PBS, pH = 7.4) and exposed to typical cancer radiotherapy. A total dose of 50 Gy was broken into 25 doses over an eleven-week period. Collected PBS was tested for polymer leachants and degradation products using Gas Chromatography Mass Spectroscopy (GC–MS), results revealed no analyzable leachants from either polymer. Scaffolds were characterized using Environmental Scanning Electron Microscopy, Size-exclusion chromatography (SEC), Differential Scanning Calorimetry (DSC) and Fourier Transform Infrared Spectroscopy (FTIR). No gross visual changes were observed in either polymer, however PU exhibited microstructure changes after irradiation. Increased number average molecular weight and weight average molecular weight in PCL and PU were observed after irradiation, indicating crosslinking. PU displayed an increase in intrinsic viscosity that further confirms increased crosslinking. PCL and PU showed decreases in crystallinity after irradiation, and PU crystallinity shifted from long-range-order hard segments to short-range-order hard segments after

  17. Influence of therapeutic radiation on polycaprolactone and polyurethane biomaterials

    International Nuclear Information System (INIS)

    Cooke, Shelley L.; Whittington, Abby R.

    2016-01-01

    ABSTRACT: Biomedical polymers are exposed in vivo to ionizing radiation as implants, coatings and bystander materials. High levels of ionizing radiation (e.g. X-ray and gamma) have been reported to cause degradation and/or cross-linking in many polymers. This pilot study sought to determine causes of failure, by investigating how therapeutic radiation affects two different porous polymeric scaffolds: polycaprolactone (PCL) and polyurethane (PU). PCL is a bioresorbable material used in biomedical devices (e.g., dentistry, internal fixation devices and targeted drug delivery capsules). PU is commonly used in medical applications (e.g., coatings for pacemakers, tissue expanders, catheter tubing and wound dressings). PU was specifically fabricated to be a non-degradable polymer in this study. Porous scaffolds, fabricated using solvent casting and/or salt leeching techniques, were placed in phosphate buffered saline (PBS, pH = 7.4) and exposed to typical cancer radiotherapy. A total dose of 50 Gy was broken into 25 doses over an eleven-week period. Collected PBS was tested for polymer leachants and degradation products using Gas Chromatography Mass Spectroscopy (GC–MS), results revealed no analyzable leachants from either polymer. Scaffolds were characterized using Environmental Scanning Electron Microscopy, Size-exclusion chromatography (SEC), Differential Scanning Calorimetry (DSC) and Fourier Transform Infrared Spectroscopy (FTIR). No gross visual changes were observed in either polymer, however PU exhibited microstructure changes after irradiation. Increased number average molecular weight and weight average molecular weight in PCL and PU were observed after irradiation, indicating crosslinking. PU displayed an increase in intrinsic viscosity that further confirms increased crosslinking. PCL and PU showed decreases in crystallinity after irradiation, and PU crystallinity shifted from long-range-order hard segments to short-range-order hard segments after

  18. Spring viremia of carp

    Science.gov (United States)

    Ahne, W.; Bjorklund, H.V.; Essbauer, S.; Fijan, N.; Kurath, G.; Winton, J.R.

    2002-01-01

    pring viremia of carp (SVC) is an important disease affecting cyprinids, mainly common carp Cyprinus carpio. The disease is widespread in European carp culture, where it causes significant morbidity and mortality. Designated a notifiable disease by the Office International des Epizooties, SVC is caused by a rhabdovirus, spring viremia of carp virus (SVCV). Affected fish show destruction of tissues in the kidney, spleen and liver, leading to hemorrhage, loss of water-salt balance and impairment of immune response. High mortality occurs at water temperatures of 10 to 17°C, typically in spring. At higher temperatures, infected carp develop humoral antibodies that can neutralize the spread of virus and such carp are protected against re-infection by solid immunity. The virus is shed mostly with the feces and urine of clinically infected fish and by carriers. Waterborne transmission is believed to be the primary route of infection, but bloodsucking parasites like leeches and the carp louse may serve as mechanical vectors of SVCV. The genome of SVCV is composed of a single molecule of linear, negative-sense, single-stranded RNA containing 5 genes in the order 3¹-NPMGL-5¹ coding for the viral nucleoprotein, phosphoprotein, matrix protein, glycoprotein, and polymerase, respectively. Polyacrylamide gel electrophoresis of the viral proteins, and sequence homologies between the genes and gene junctions of SVCV and vesicular stomatitis viruses, have led to the placement of the virus as a tentative member of the genus Vesiculovirus in the family Rhabdoviridae. These methods also revealed that SVCV is not related to fish rhabdoviruses of the genus Novirhabdovirus. In vitro replication of SVCV takes place in the cytoplasm of cultured cells of fish, bird and mammalian origin at temperatures of 4 to 31°C, with an optimum of about 20°C. Spring viremia of carp can be diagnosed by clinical signs, isolation of virus in cell culture and molecular methods. Antibodies directed

  19. Basaltic substrate composition affects microbial community development and acts as a source of nutrients in the deep biosphere

    Science.gov (United States)

    Bailey, B.; Sudek, L.; Templeton, A.; Staudigel, H.; Tebo, B.; Moyer, C.; Davis, R.

    2006-12-01

    metabolizing isolates which are able to grow with basalt as their only source of phosphate and electron donors and acceptors, which indicates that they are capable of leeching nutrients required for metabolism directly from the rock surface. Characterizing these chemolithoautotrophic microbes and the environments in which they are found can dramatically increase our understanding of the breadth and significance of the biosphere as it pertains to global seawater and ocean crust element cycling.

  20. [Metazoan parasites of Micropterus salmoides (Centrarchidae: Perciformes) from reservoirs of Nuevo León, México and their association with condition factor and gender].

    Science.gov (United States)

    Galaviz S, Lucio; Escobar G, Baldemar; Iruegas B, Francisco Javier; Molina, Zinnia Judith

    2016-06-01

    The largemouth bass Micropterus salmoides is a very valuable fish species for aquaculture and sport fishing; however, there are no systematic studies on fish metazoan parasites in Mexico. The main objective of the present study was to describe the prevalence, abundance, and intensity of M. salmoides metazoan parasites, and their association with fish condition factor and gender. The sample size was composed by 672 hosts, collected between 2011-2013 from the following reservoirs of Nuevo Leon, México: Rodrigo Gómez dam (“La Boca”, LB), Cuchillo-Solidaridad dam (CS), Salinillas lagoon (LS), Mariano Escobedo dam (“Sombreretillo”, S), and José López Portillo dam (“Cerro Prieto”, CP). Living fish were transported to the laboratory; sizes and weights were then recorded to calculate the Fulton condition factor (k). If possible, gender was also recorded. Parasites were detected under stereoscopy, recollected and preserved by traditional techniques. Statistical analysis of association between parasitic load, gender, and Fulton condition factor were calculated, using the X2 and the Student-t tests. Results showed that 12 different metazoans were identified, two flukes (Posthodiplostomum minimum centrarchi and Phyllodistomum pearsei), one tapeworm (Proteocephalus ambloplitis), three roundworms (Contracaecum sp., Spinitectus carolini and Philometra nodulosa), two acantocephalan (Neoechinorhynchus cylindratus and Arhythmorhynchus sp.), one leech (Myzobdella moorei), and three copepods (Ergasilus versicolor; Ergasilus arthrosis and Ergasilus cerastes). HSD Tukey test showed that infected fish from LB were significantly different than LS, CS, CP, and S (PParasites most commonly collected in all five locations were P. m. centrarchi, Contracaecum sp. and E. versicolor. The frequency of P. m. centrarchi was highly significant (Pparasites; furthermore, this parasite showed the highest prevalence (97.5 %), abundance (10.12-83.6), and intensity (15.44-88.5). Statistical