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1

Disarming the box-jellyfish: nematocyst inhibition in Chironex fleckeri.  

PubMed

Laboratory tests indicate that methylated spirits, widely espoused as a first-aid treatment for jellyfish stings, causes massive discharge of nematocysts in living tentacles of the box-jellyfish, Chironex fleckeri. This action, together with demonstrated hazards of flammability and intoxication, casts doubt on this substance as a treatment for Chironex stings. In an attempt to find a substitute which will be effective in inactivating unfired nematocysts in the tentacles adhering to sting victims, a number of substances were tested in the laboratory. Weak solutions of acetic acid, as well as commerical vinegar, were found to inactivate the penetrating nematocysts of Chironex rapidly and completely. Most other substances tested proved less effective, and some actually stimulated the firing of nematocysts. PMID:6102347

Hartwick, R; Callanan, V; Williamson, J

1980-01-12

2

Venom proteome of the box jellyfish Chironex fleckeri.  

PubMed

The nematocyst is a complex intracellular structure unique to Cnidaria. When triggered to discharge, the nematocyst explosively releases a long spiny, tubule that delivers an often highly venomous mixture of components. The box jellyfish, Chironex fleckeri, produces exceptionally potent and rapid-acting venom and its stings to humans cause severe localized and systemic effects that are potentially life-threatening. In an effort to identify toxins that could be responsible for the serious health effects caused by C. fleckeri and related species, we used a proteomic approach to profile the protein components of C. fleckeri venom. Collectively, 61 proteins were identified, including toxins and proteins important for nematocyte development and nematocyst formation (nematogenesis). The most abundant toxins identified were isoforms of a taxonomically restricted family of potent cnidarian proteins. These toxins are associated with cytolytic, nociceptive, inflammatory, dermonecrotic and lethal properties and expansion of this important protein family goes some way to explaining the destructive and potentially fatal effects of C. fleckeri venom. Venom proteins and their post-translational modifications (PTMs) were further characterized using toxin-specific antibodies and phosphoprotein/glycoprotein-specific stains. Results indicated that glycosylation is a common PTM of the toxin family while a lack of cross-reactivity by toxin-specific antibodies infers there is significant divergence in structure and possibly function among family members. This study provides insight into the depth and diversity of protein toxins produced by harmful box jellyfish and represents the first description of a cubozoan jellyfish venom proteome. PMID:23236347

Brinkman, Diane L; Aziz, Ammar; Loukas, Alex; Potriquet, Jeremy; Seymour, Jamie; Mulvenna, Jason

2012-01-01

3

Venom Proteome of the Box Jellyfish Chironex fleckeri  

PubMed Central

The nematocyst is a complex intracellular structure unique to Cnidaria. When triggered to discharge, the nematocyst explosively releases a long spiny, tubule that delivers an often highly venomous mixture of components. The box jellyfish, Chironex fleckeri, produces exceptionally potent and rapid-acting venom and its stings to humans cause severe localized and systemic effects that are potentially life-threatening. In an effort to identify toxins that could be responsible for the serious health effects caused by C. fleckeri and related species, we used a proteomic approach to profile the protein components of C. fleckeri venom. Collectively, 61 proteins were identified, including toxins and proteins important for nematocyte development and nematocyst formation (nematogenesis). The most abundant toxins identified were isoforms of a taxonomically restricted family of potent cnidarian proteins. These toxins are associated with cytolytic, nociceptive, inflammatory, dermonecrotic and lethal properties and expansion of this important protein family goes some way to explaining the destructive and potentially fatal effects of C. fleckeri venom. Venom proteins and their post-translational modifications (PTMs) were further characterized using toxin-specific antibodies and phosphoprotein/glycoprotein-specific stains. Results indicated that glycosylation is a common PTM of the toxin family while a lack of cross-reactivity by toxin-specific antibodies infers there is significant divergence in structure and possibly function among family members. This study provides insight into the depth and diversity of protein toxins produced by harmful box jellyfish and represents the first description of a cubozoan jellyfish venom proteome. PMID:23236347

Brinkman, Diane L.; Aziz, Ammar; Loukas, Alex; Potriquet, Jeremy; Seymour, Jamie; Mulvenna, Jason

2012-01-01

4

Techniques applicable for purifying Chironex fleckeri (box-jellyfish) venom.  

PubMed

A survey of several techniques to isolate a purified lethal factor from the tentacles of Chironex fleckeri was completed. Heterologous band patterns were obtained from specific eluates after gel filtration, ion exchange, immunoaffinity and hydrophobic chromatography. SDS-PAGE revealed a dense band at 24,000 mol. wt in many of these fractions. Isoelectric focusing of the crude venom resulted in considerable loss of activity but indicated significant purification in the fractions having a pI of 5.2-6.8. These fractions were also immunologically active against sera from a convalescing post-evenomation patient. The primary difficulties encountered in jellyfish venom purification are the lack of stability and the tendency of the active toxins to adhere to each other and to various support matrices. PMID:1977211

Othman, I; Burnett, J W

1990-01-01

5

Partial purification of box jellyfish ( Chironex fleckeri) nematocyst venom isolated at the beachside  

Microsoft Academic Search

Chironex fleckeri, the northern Australian box jellyfish produces one of, if not, the most potent animal venoms. Study of the venom has been hampered by the limits of the animals' range and the venom's thermolability. Using retained lethality and native polyacrylamide gel electrophoresis (NPAGE), we show that lyophilization of autolysis isolated nematocysts is an effective method of transporting the venom.

David A. Bloom; Joseph W. Burnett; Philip Alderslade

1998-01-01

6

The Mechanism Underlying the Cardiotoxic Effect of the Toxin from the Jellyfish Chironex fleckeri  

Microsoft Academic Search

We have investigated the mechanisms underlying the cardiac effects of the toxin from the box jellyfish Chironex fleckeri. Papillary muscles isolated from the hearts of ferrets and ventricular myocytes isolated from the hearts of ferrets and rats were used. Force, intracellular [Ca2+], and membrane potential were monitored in the papillary muscles; contraction, intracellular [Ca2+], intracellular [Na+], and membrane currents were

M. R. Mustafa; E. White; K. Hongo; I. Othman; C. H. Orchard

1995-01-01

7

The effects of antivenom and verapamil on the haemodynamic actions of Chironex fleckeri (box jellyfish) venom.  

PubMed

The efficacy of antivenom and verapamil against Chironex fleckeri (box jellyfish) venom was investigated in monitored mechanically ventilated piglets. Chironex fleckeri tentacle extract alone, a mixture of tentacle extract with antivenom, and verapamil before tentacle extract were administered intravenously to groups of animals. Tentacle extract caused severe systemic hypotension, cardiac dysrrhythmias, pulmonary hypertension, haemolysis and hyperkalaemia. These effects were prevented by pre-incubation of tentacle extract with antivenom. Verapamil did not prevent any effect of venom, exacerbated cardiovascular collapse and increased mortality. We conclude that antivenom neutralizes the cardiovascular, haemolytic and hyperkalaemic effects of box jellyfish venom. Verapamil does not prevent any of these effects and is contra-indicated for treatment of envenomation. PMID:9513666

Tibballs, J; Williams, D; Sutherland, S K

1998-02-01

8

Acute management of serious envenomation by box-jellyfish (Chironex fleckeri).  

PubMed

Two cases of serious envenomation by the northern Australian box-jellyfish (Chironex fleckeri) are reported. The first-aid measures and the subsequent management and follow-up of patients are discussed. In addition to its known life-saving effects, the early administration of the specific antivenom appears to be the best treatment for the savage pain of the sting, and may also result in a reduction of subsequent skin scarring. PMID:6150421

Williamson, J A; Le Ray, L E; Wohlfahrt, M; Fenner, P J

9

Response of the box-jellyfish (Chironex fleckeri) cardiotoxin to intravenous administration of verapamil.  

PubMed

Verapamil, a calcium antagonist, has been shown to be effective in delaying death in mice after intravenous challenge with box-jellyfish (Chironex fleckeri) venom. Death from a challenge of up to three mouse-lethal doses of venom was significantly delayed after the prior intravenous administration of verapamil (P = 0.003). A smaller dose of verapamil could "rescue" mice previously envenomed with 1.25 mouse-lethal doses (P = 0.0001). These data suggest that verapamil injections should be added to the first-aid procedures performed on the beach for victims of box-jellyfish stings. PMID:6135976

Burnett, J W; Calton, G J

1983-08-20

10

Identification, cloning and sequencing of two major venom proteins from the box jellyfish, Chironex fleckeri.  

PubMed

Two of the most abundant proteins found in the nematocysts of the box jellyfish Chironex fleckeri have been identified as C. fleckeri toxin-1 (CfTX-1) and toxin-2 (CfTX-2). The molecular masses of CfTX-1 and CfTX-2, as determined by SDS-PAGE, are approximately 43 and 45 kDa, respectively, and both proteins are strongly antigenic to commercially available box jellyfish antivenom and rabbit polyclonal antibodies raised against C. fleckeri nematocyst extracts. The amino acid sequences of mature CfTX-1 and CfTX-2 (436 and 445 residues, respectively) share significant homology with three known proteins: CqTX-A from Chiropsalmus quadrigatus, CrTXs from Carybdea rastoni and CaTX-A from Carybdea alata, all of which are lethal, haemolytic box jellyfish toxins. Multiple sequence alignment of the five jellyfish proteins has identified several short, but highly conserved regions of amino acids that coincide with a predicted transmembrane spanning region, referred to as TSR1, which may be involved in a pore-forming mechanism of action. Furthermore, remote protein homology predictions for CfTX-2 and CaTX-A suggest weak structural similarities to pore-forming insecticidal delta-endotoxins Cry1Aa, Cry3Bb and Cry3A. PMID:17688901

Brinkman, Diane; Burnell, James

2007-11-01

11

Stabilization of lethal and hemolytic activities of box jellyfish (Chironex fleckeri) venom.  

PubMed

The stability of both the lethal and hemolytic activities of box jellyfish (Chironex fleckeri) tentacle extract was assessed after various extraction procedures. Both activities were higher when no buffers or water were used during the initial extraction. Also, when the extract was first filtered through a Sep-pak C18 cartridge, the residual lethal titre, after incubation for 24 hr at room temperature, was increased 16-fold and hemolysis was increased 2.6-fold. Evidence for proteolytic activity in the extract was also obtained and monitored by size exclusion HPLC. PMID:2567076

Comis, A; Hartwick, R F; Howden, M E

1989-01-01

12

Monoclonal antibodies neutralizing the haemolytic activity of box jellyfish (Chironex fleckeri) tentacle extracts.  

PubMed

1. Three monoclonal antibodies have been produced which neutralize in vitro the haemolytic activity present in tentacle extracts of the box jellyfish (Chironex fleckeri). 2. Two of these monoclonal antibodies bound specifically to a component of relative molecular mass 50,000 in tentacle extract on Western blots. 3. This binding only occurred when the extracts were electrophoresed under non-reducing conditions. 4. The third monoclonal antibody did not display binding to Western blots of tentacle extract under any of our experimental conditions. PMID:8104761

Collins, S P; Comis, A; Marshall, M; Hartwick, R F; Howden, M E

1993-09-01

13

Partial purification of cytolytic venom proteins from the box jellyfish, Chironex fleckeri.  

PubMed

Venom proteins from the nematocysts of Chironex fleckeri were fractionated by size-exclusion and cation-exchange chromatography. Using sheep erythrocyte haemolysis as an indicator of cytolytic activity, two major cytolysins, with native molecular masses of approximately 370 and 145kDa, and one minor cytolysin ( approximately 70kDa) were isolated. SDS-PAGE and western blot protein profiles revealed that the 370kDa haemolysin is composed of CfTX-1 and CfTX-2 subunits ( approximately 43 and 45kDa, respectively); the most abundant proteins found in C. fleckeri nematocyst extracts. The 145kDa haemolysin predominately contains two other major proteins ( approximately 39 and 41kDa), which are not antigenic towards commercially available box jellyfish antivenom or rabbit polyclonal antibodies raised against whole C. fleckeri nematocyst extracts or CfTX-1 and -2. The kinetics of CfTX-1 and -2 haemolytic activities are temperature dependent and characterised by a pre-lytic lag phase ( approximately 6-7min) prior to initiation of haemolysis. Significant amino acid sequence homology between the CfTX proteins and other box jellyfish toxins suggest that CfTX-1 and -2 may also be lethal and dermonecrotic. Therefore, further in vivo and in vitro studies are required to investigate the potential roles of CfTX-1 and -2 in the lethal effects of C. fleckeri venom. PMID:18243272

Brinkman, Diane; Burnell, James

2008-04-01

14

Fatal envenomation by Chironex fleckeri, the north Australian box jellyfish: the continuing search for lethal mechanisms.  

PubMed

A child with severe envenomation by Chironex fleckeri presented in cardiac arrest at a hospital between 15 and 20 min after the sting was sustained. Resuscitation was not successful. Objective confirmation of C. fleckeri as the cause of death is described. Four metres of tentacle contact in this case represents the smallest-measured fatal C. fleckeri sting that has been recorded so far. The mechanism of this death was toxic and not allergic. The available clinical information suggests direct myocardial interference, but does not exclude a respiratory hypoxic element. A more widespread venom-induced functional disruption of the cell membrane is postulated, with a resultant dysfunction in several vital organ systems that were acting in concert. Early, vigorous and sustained resuscitation that is performed as a first-aid measure offers the best hope of prehospital survival after a massive C. fleckeri sting, which is the most explosive envenomation process that is presently known to humans. In-hospital resuscitation from unresponsive circulatory arrest should now involve intravenously-administered verapamil (or its equivalent) and additional box-jellyfish antivenom, while the patient is being monitored. PMID:2897074

Lumley, J; Williamson, J A; Fenner, P J; Burnett, J W; Colquhoun, D M

1988-05-16

15

An in vivo examination of the stability of venom from the Australian box jellyfish Chironex fleckeri.  

PubMed

We have previously characterised the pharmacological activity of a number of jellyfish venoms with a particular emphasis on the profound cardiovascular effects. It has been suggested that jellyfish venoms are difficult to work with and are sensitive to pH, temperature and chemical changes. The current study aimed to examine the working parameters of the venom of the Australian box jellyfish Chironex fleckeri to enable fractionation and isolation of the toxins with cardiovascular activity. C. fleckeri venom was made up fresh each day and subjected to a number of different environments (i.e. a pH range of 5-9 and a temperature range of 4-30 degrees C). In addition, the effect of freeze drying and reconstituting the venom was investigated. Venom (50 microg/kg, i.v.) produced a transient hypertensive response followed by cardiovascular collapse in anaesthetised rats. This biphasic response was not significantly effected by preparation of the venom at a pH of 5, 7 or 9. Similarly, venom (50 microg/kg, i.v.) did not display a loss of activity when exposed to temperatures of 4, 20 or 30 degrees C for 1.5h. However, the cardiovascular activity was abolished by boiling the venom. Freeze drying, and then reconstituting, the venom did not significantly affect its cardiovascular activity. However, repeated freeze drying and reconstituting of extracted venom resulted in a significantly loss of activity. This study provides a more detailed knowledge of the parameters in which C. fleckeri venom can be used and, while supporting some previous studies, contradicts some of the perceived problems of working with the venom. PMID:17215014

Winter, K L; Isbister, G K; Seymour, J E; Hodgson, W C

2007-05-01

16

Partial purification of box jellyfish (Chironex fleckeri) nematocyst venom isolated at the beachside.  

PubMed

Chironex fleckeri, the northern Australian box jellyfish produces one of, if not, the most potent animal venoms. Study of the venom has been hampered by the limits of the animals' range and the venom's thermolability. Using retained lethality and native polyacrylamide gel electrophoresis (NPAGE), we show that lyophilization of autolysis isolated nematocysts is an effective method of transporting the venom. In addition, Sephadex G-200 chromatography, spin concentration, and NPAGE fail to demonstrate the presence of a 600 kDa protein to which the bulk of the lethal activity has been ascribed. Sodium dodecyl sulfate capillary electrophoresis of crude venom yields several protein bands with a molecular weight range of 30-200 kDa. Freeze-thaw studies show a loss of activity and NPAGE bands after two freeze thaw cycles. PMID:9690776

Bloom, D A; Burnett, J W; Alderslade, P

1998-08-01

17

Toxins from the box-jellyfish Chironex fleckeri.  

PubMed

Two myotoxins (T1 and T2) with mol. wts of approximately 600,000 and 150,000, respectively, and a haemolysin (T3) with a mol. wt of approximately 70,000 were isolated from the crude nematocyst venom of C. fleckeri by the use of Sephadex G-200 chromatography. A neurotoxic fraction (T4) and a haemolytic fraction (T5) containing proteins with apparent mol. wts of approximately 150,000 and 70,000, respectively, were also isolated by Sephadex chromatography from crude extracts of tentacular material from which nematocysts had been removed. The three nematocyst toxins and the two toxic fractions from tentacle extracts were lethal to mice on i.v. injection. After SDS-PAGE the myotoxins T1 and T2 yielded similar major bands corresponding with mol. wts different from those yielded by T3 and the toxic tentacle fractions. T1 and T2 appeared to be comprised of aggregations of subunits with mol. wts of approximately 18,000. On HPLC, crude nematocyst venom and the nematocyst toxins T1 and T2 lost their myotoxic properties. The need for thorough removal of extraneous tentacular material from isolated nematocysts, the need for effective rupture of nematocysts, the need to counter the lability of the nematocyst venom and the need to use myotoxicity as a criterion of venom activity if the active components of the venom are to be purified and characterized are emphasized. PMID:8099238

Endean, R; Monks, S A; Cameron, A M

1993-04-01

18

Pharmacologically distinct cardiovascular effects of box jellyfish ( Chironex fleckeri) venom and a tentacle-only extract in rats  

Microsoft Academic Search

Using a recently developed technique to extract jellyfish venom from nematocysts, the present study investigated the in vivo cardiovascular effects of Chironex fleckeri venom and tentacle extract (devoid of nematocysts). In anaesthetised rats, venom (10?g\\/kg, i.v.) produced a transient pressor response (23±4mmHg) followed, in two of five animals, by cardiovascular collapse. Tentacle extract (100?g\\/kg, i.v.) produced a more prolonged hypertensive

Sharmaine Ramasamy; Geoffrey K. Isbister; Jamie E. Seymour; Wayne C. Hodgson

2005-01-01

19

The mechanism underlying the cardiotoxic effect of the toxin from the jellyfish Chironex fleckeri.  

PubMed

We have investigated the mechanisms underlying the cardiac effects of the toxin from the box jellyfish Chironex fleckeri. Papillary muscles isolated from the hearts of ferrets and ventricular myocytes isolated from the hearts of ferrets and rats were used. Force, intracellular [Ca2+], and membrane potential were monitored in the papillary muscles; contraction, intracellular [Ca2+], intracellular [Na+], and membrane currents were monitored in the isolated myocytes. Application of the toxin to these preparations resulted in a large increase in intracellular [Ca2+] and the adverse symptoms of Ca2+ overload (aftercontractions, spontaneous contractions, a decrease in developed force, and an increase in resting force). The response of papillary muscles to the toxin was not inhibited by blockers of Ca2+ or Na+ channels or by inhibitors of the sarcoplasmic reticulum, Na+/K+ ATPase, or Na+/H+ exchange. The response to the toxin was, however, blocked by prior exposure to a solution which contained no Na+ and by Ni2+. In the isolated myocytes, as well as an increase in intracellular [Ca2+], the toxin also caused an increase in intracellular [Na+] and the appearance of a current which was inward at negative potentials and reversed at about -10 mV. These data can be explained by the toxin increasing Na+ influx into the cell. The increase in intracellular [Na+] will then increase intracellular [Ca2+] via the Na+/Ca2+ exchange mechanism, thus producing the observed Ca2+ overload. PMID:7645014

Mustafa, M R; White, E; Hongo, K; Othman, I; Orchard, C H

1995-08-01

20

Effects of verapamil and CSL antivenom on Chironex fleckeri (box-jellyfish) induced mortality.  

PubMed

Ovine antivenom prolonged survival in mice challenged with intravenous Chironex fleckeri venom over a limited dose range. Verapamil enhanced the beneficial effect of ovine antivenom. This data suggests that there may be an, as yet undefined, optimal antivenom dose for humans and that verapamil, used in combination with antivenom is an effective agent. PMID:10482395

Bloom, D A; Burnett, J W; Hebel, J R; Alderslade, P

1999-11-01

21

The in vivo cardiovascular effects of box jellyfish Chironex fleckeri venom in rats: efficacy of pre-treatment with antivenom, verapamil and magnesium sulphate  

Microsoft Academic Search

Using a new technique to extract venom from the nematocysts, the efficacy of CSL box jellyfish antivenom (AV) and adjunct therapies, verapamil and magnesium sulfate (MgSO4), were investigated against the in vivo cardiovascular effects of Chironex fleckeri venom in anaesthetised rats.C. fleckeri venom (30 ?g\\/kg; i.v.) produced a transient hypertensive response followed by hypotension and cardiovascular collapse within 4 min

Sharmaine Ramasamy; Geoffrey K. Isbister; Jamie E. Seymour; Wayne C. Hodgson

2004-01-01

22

Chironex fleckeri (box jellyfish) venom proteins: expansion of a cnidarian toxin family that elicits variable cytolytic and cardiovascular effects.  

PubMed

The box jellyfish Chironex fleckeri produces extremely potent and rapid-acting venom that is harmful to humans and lethal to prey. Here, we describe the characterization of two C. fleckeri venom proteins, CfTX-A (?40 kDa) and CfTX-B (?42 kDa), which were isolated from C. fleckeri venom using size exclusion chromatography and cation exchange chromatography. Full-length cDNA sequences encoding CfTX-A and -B and a third putative toxin, CfTX-Bt, were subsequently retrieved from a C. fleckeri tentacle cDNA library. Bioinformatic analyses revealed that the new toxins belong to a small family of potent cnidarian pore-forming toxins that includes two other C. fleckeri toxins, CfTX-1 and CfTX-2. Phylogenetic inferences from amino acid sequences of the toxin family grouped CfTX-A, -B, and -Bt in a separate clade from CfTX-1 and -2, suggesting that the C. fleckeri toxins have diversified structurally and functionally during evolution. Comparative bioactivity assays revealed that CfTX-1/2 (25 ?g kg(-1)) caused profound effects on the cardiovascular system of anesthetized rats, whereas CfTX-A/B elicited only minor effects at the same dose. Conversely, the hemolytic activity of CfTX-A/B (HU50 = 5 ng ml(-1)) was at least 30 times greater than that of CfTX-1/2. Structural homology between the cubozoan toxins and insecticidal three-domain Cry toxins (?-endotoxins) suggests that the toxins have a similar pore-forming mechanism of action involving ?-helices of the N-terminal domain, whereas structural diversification among toxin members may modulate target specificity. Expansion of the cnidarian toxin family therefore provides new insights into the evolutionary diversification of box jellyfish toxins from a structural and functional perspective. PMID:24403082

Brinkman, Diane L; Konstantakopoulos, Nicki; McInerney, Bernie V; Mulvenna, Jason; Seymour, Jamie E; Isbister, Geoffrey K; Hodgson, Wayne C

2014-02-21

23

Growth, development and temporal variation in the onset of six Chironex fleckeri medusae seasons: a contribution to understanding jellyfish ecology.  

PubMed

Despite the worldwide distribution, toxicity and commercial, industrial and medical impacts jellyfish present, many aspects of their ecology remain poorly understood. Quantified here are important ecological parameters of Chironex fleckeri medusae, contributing not only to the understanding of an understudied taxon, the cubozoa, but also to the broader understanding of jellyfish ecology. C. fleckeri medusae were collected across seven seasons (1999, 2000, 2003, 2005-07 and 2010), with growth rates, temporal variation in the medusae season onset and differences in population structure between estuarine and coastal habitats quantified. With a mean of 2 September ± 2 d (mean ± 95% confidence limits), the earliest date of metamorphosis was temporally constrained between seasons, varying by only 7 d (30 August to 5 September). Juvenile medusae appeared to be added over an extended period, suggesting polyp metamorphosis was an ongoing process once it commenced. At a maximum of 3 ± 0.2 mm d(-1) IPD, medusae growth to an asymptotic size of ~190 mm IPD was rapid, yet, with the oldest medusae estimated to be ~78 d in age, medusae did not appear to accumulate along the coastline. Furthermore, a greater proportion of juveniles were observed along the coastline, with estuarine populations typified by larger medusae. With key aspects of C. fleckeri's ecology now quantified, medusae season management protocols can be further developed. PMID:22384009

Gordon, Matthew; Seymour, Jamie

2012-01-01

24

Clinical implications of research on the box-jellyfish Chironex fleckeri.  

PubMed

Despite several decades of laboratory research, many anecdotal clinical publications and successful production of antivenom, the active components of Chironex fleckeri venom and their mechanisms of toxicity remain poorly elucidated. Conflicting results of animal experiments and venom studies and the lack of controlled clinical trials necessitate caution in formulating protocols of clinical management. Of particular note are that in severe envenomation (1) clinical deterioration can occur within minutes and cardiac support must be emphasised in addition to respiratory support; (2) larger doses of antivenom may be appropriate; and (3) recommendations of therapy with verapamil and other cardioactive drugs remain controversial. PMID:7886690

Currie, B

1994-11-01

25

Pharmacologically distinct cardiovascular effects of box jellyfish (Chironex fleckeri) venom and a tentacle-only extract in rats.  

PubMed

Using a recently developed technique to extract jellyfish venom from nematocysts, the present study investigated the in vivo cardiovascular effects of Chironex fleckeri venom and tentacle extract (devoid of nematocysts). In anaesthetised rats, venom (10 microg/kg, i.v.) produced a transient pressor response (23+/-4 mmHg) followed, in two of five animals, by cardiovascular collapse. Tentacle extract (100 microg/kg, i.v.) produced a more prolonged hypertensive effect (31+/-3 mmHg) without cardiovascular collapse. Prazosin (50 microg/kg, i.v.) did not have any significant effect on the cardiovascular effects produced by venom. However, prazosin significantly attenuated the pressor response produced by tentacle extract. Ketanserin (1 mg/kg, i.v.) did not have any significant effect on the cardiovascular response of the anaesthetised rat to venom (10 microg/kg, i.v.; 25+/-1 mmHg). Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) was performed to compare the two jellyfish samples used in the present study. In addition to ensuring reproducibility of future studies and allow comparison with previous research. We show, for the first time, that a pure venom sample extracted from C. fleckeri nematocysts and a tentacle extract have cardiovascular effects in the anaesthetised rat which are different and pharmacologically distinct. PMID:15603916

Ramasamy, Sharmaine; Isbister, Geoffrey K; Seymour, Jamie E; Hodgson, Wayne C

2005-02-15

26

Serious envenomation by the Northern Australian box-jellyfish (Chironex fleckeri).  

PubMed

Serious envenomation of an adult pregnant woman by a box-jellyfish (Chironex flecteri) in North Queensland is reported. Quick thinking and resuscitation by bystanders which was followed by early hospital treatment resulted in a successful outcome both for mother and for fetus. A brief review of the historic background of box-jellyfish envenomation is given, and some specific problems concerning the management and prevention of envenomation from this unique animal are described. On-the-spot resuscitation takes absolute priority, and the advent of specific antivenom is a major advance. Avoidance of fetal stings in the future is possible by simple preventive measures. The role of the Surf Life Saving Association of Australia in the prevention and treatment of such problems is highlighted, and, as a result of recent research, possible changes in the management of box-jellyfish envenomations are predicted. PMID:6102346

Williamson, J A; Callanan, V I; Hartwick, R F

1980-01-12

27

Rapid short term and gradual permanent cardiotoxic effects of vertebrate toxins from Chironex fleckeri (Australian box jellyfish) venom.  

PubMed

The vertebrate cardiotoxic components of the venom produced by the Australian box jellyfish, Chironex fleckeri, have not previously been isolated. We have uncovered for the first time, three distinct cytotoxic crude fractions from within the vertebrate cardiotoxic peak of C. fleckeri venom by monitoring viability of human muscle cells with an impedance based assay (ACEA xCELLigence system) measuring cell detachment as cytotoxicity which was correlated with a reduction in cell metabolism using a cell proliferation (MTS) assay. When the effects of the venom components on human cardiomyocytes and human skeletal muscle cells were compared, two fractions were found to specifically affect cardiomyocytes with distinct temporal profiles (labelled Crude Toxic Fractions (CTF), ? and ?). A third fraction (CTF-?) was toxic to both muscle cell types and therefore not cardio specific. The vertebrate, cardio specific CTF-? and CTF-?, presented distinct activities; CTF-? caused rapid but short term cell detachment and reduction in cell metabolism with enhanced activity at lower concentrations than CTF-?. This activity was not permanent, with cell reattachment and subsequent increased metabolism of heart muscle cells observed when exposed to all but the highest concentrations of CTF-? tested. The cytotoxic effect of CTF-? took twice as long to act on the cells compared to CTF-?, however, the activity was permanent. Furthermore, we showed that the two fractions combined have a synergistic effect causing a much stronger and faster cell detachment (death) when combined than the sum of the individual effects of each toxin. These data presented here improves the current understanding of the toxic mechanisms of the Australian box jellyfish, C. fleckeri, and provides a basis for in vivo research of these newly isolated toxic fractions. PMID:24462661

Chaousis, Stephanie; Smout, Michael; Wilson, David; Loukas, Alex; Mulvenna, Jason; Seymour, Jamie

2014-03-01

28

The in vitro effects of two chirodropid (Chironex fleckeri and Chiropsalmus sp.) venoms: efficacy of box jellyfish antivenom.  

PubMed

The pharmacological and biochemical isolation of cnidarian venoms has been hindered by difficulties with both extracting pure venom from nematocysts and venom stability. The development of a new technique to extract active, pure venom of Chironex fleckeri and Chiropsalmus sp. has enabled identify both neurotoxic and myotoxic activity in their venoms. These activities are similar, but not identical in each species. Venom (50 micro g/ml) from both species significantly inhibited indirect and direct twitches of the chick biventer nerve-muscle preparation. Pre-incubation with 1U/ml box jellyfish antivenom did not have any significant effect on venom-induced reductions of indirect twitches. However, this activity was markedly attenuated by prior addition of 5U/ml antivenom, albeit to a lesser degree for Chiropsalmus sp. In contrast, prior addition of 5U/ml box jellyfish antivenom did not neutralise the myotoxic activity of C. fleckeri venom (50 micro g/ml), although it did inhibit the myotoxicity produced by Chiropsalmus sp. venom (50 micro g/ml). Antivenom (5U/ml) added 1h after the addition of C. fleckeri venom (50 micro g/ml) had no effect on the indirect or direct twitches of the skeletal muscle preparation. However, it partially restored the reduction in indirect twitch height caused by Chiropsalmus sp. venom (50 micro g/ml). Myotoxicity was confirmed in muscle preparations stained with hematoxylin and eosin.Therefore, although antivenom was able to neutralize the neurotoxic effects of both species, and the myotoxic effects of Chiropsalmus sp., when added prior to venom, it was unable to reverse the effects after venom addition. This suggests that antivenom is unlikely to be useful in the treatment of neurotoxic or myotoxic effects in patients, although these effects are rarely seen clinically. PMID:12727274

Ramasamy, Sharmaine; Isbister, Geoff K; Seymour, Jamie E; Hodgson, Wayne C

2003-05-01

29

Firing the Sting: Chemically Induced Discharge of Cnidae Reveals Novel Proteins and Peptides from Box Jellyfish (Chironex fleckeri) Venom.  

PubMed

Cnidarian venom research has lagged behind other toxinological fields due to technical difficulties in recovery of the complex venom from the microscopic nematocysts. Here we report a newly developed rapid, repeatable and cost effective technique of venom preparation, using ethanol to induce nematocyst discharge and to recover venom contents in one step. Our model species was the Australian box jellyfish (Chironex fleckeri), which has a notable impact on public health. By utilizing scanning electron microscopy and light microscopy, we examined nematocyst external morphology before and after ethanol treatment and verified nematocyst discharge. Further, to investigate nematocyst content or "venom" recovery, we utilized both top-down and bottom-up transcriptomics-proteomics approaches and compared the proteome profile of this new ethanol recovery based method to a previously reported high activity and recovery protocol, based upon density purified intact cnidae and pressure induced disruption. In addition to recovering previously characterized box jellyfish toxins, including CfTX-A/B and CfTX-1, we recovered putative metalloproteases and novel expression of a small serine protease inhibitor. This study not only reveals a much more complex toxin profile of Australian box jellyfish venom but also suggests that ethanol extraction method could augment future cnidarian venom proteomics research efforts. PMID:25793725

Jouiaei, Mahdokht; Casewell, Nicholas R; Yanagihara, Angel A; Nouwens, Amanda; Cribb, Bronwen W; Whitehead, Darryl; Jackson, Timothy N W; Ali, Syed A; Wagstaff, Simon C; Koludarov, Ivan; Alewood, Paul; Hansen, Jay; Fry, Bryan G

2015-01-01

30

Cardiotoxic effects of venom fractions from the Australian box jellyfish Chironex fleckeri on human myocardiocytes.  

PubMed

An investigation into the cardiotoxic effects in human cardiomyocytes of different fractions (as produced from an FPLC) of the venom from Chironex fleckeri showed that whole venom caused cardiac cell death in minutes, measured as cell detachment using xCELLigence technology. However, only one fraction of the venom was responsible for this effect. When all extracted venoms were recombined a similar result was seen for the toxic fraction, however these effects were slower than unfractionated venom alone even though the concentrations were similar. The difference in the results between fractioned and unfractionated venom may have been caused by compounds remaining in the FPLC column, which may interact with the toxic fraction to cause rapid cell detachment or death. PMID:22560886

Saggiomo, Silvia L A; Seymour, Jamie E

2012-09-01

31

A pharmacological investigation of the venom extract of the Australian box jellyfish, Chironex fleckeri, in cardiac and vascular tissues.  

PubMed

The pharmacology of Australian box jellyfish, Chironex fleckeri, unpurified (crude) nematocyst venom extract (CVE) was investigated in rat isolated cardiac and vascular tissues and in anaesthetised rats. In small mesenteric arteries CVE (0.01-30 ?g/ml) caused contractions (EC(50) 1.15±0.19 ?g/ml) that were unaffected by prazosin (0.1 ?M), bosentan (10 ?M), CGRP(8-37) (1 ?M) or tetrodotoxin (1 ?M). Box jellyfish antivenom (5-92.6 units/ml) caused rightward shifts of the CVE concentration-response curve with no change in the maximum. In the presence of l-NAME (100 ?M) the sensitivity and maximum response to CVE were increased, whilst MgSO(4) (6 mM) decreased both parameters. CVE (1-10 ?g/ml) caused inhibition of the contractile response to electrical sympathetic nerve stimulation. Left atrial responses to CVE (0.001-30 ?g/ml) were bi-phasic, composed of an initial positive inotropy followed by a marked negative inotropy and atrial standstill. CVE (0.3 ?g/ml) elicited a marked decrease in right atrial rate followed by atrial standstill at 3 ?g/ml. These responses were unaffected by 1 ?M of propranolol, atropine or CGRP(8-37). Antivenom (54 and 73 units/ml) caused rightward shifts of the CVE concentration-response curve and prevented atrial standstill in left and right atria. The effects of CVE do not appear to involve autonomic nerves, post-synaptic ?(1)- or ?(1)-adrenoceptors, or muscarinic, endothelin or CGRP receptors, but may occur through direct effects on the cardiac and vascular muscle. Box jellyfish antivenom was effective in attenuating CVE-induced responses in isolated cardiac and vascular tissues. PMID:22154831

Hughes, Richard J A; Angus, James A; Winkel, Kenneth D; Wright, Christine E

2012-02-25

32

The effectiveness of antivenom in countering the actions of box-jellyfish (Chironex fleckeri) nematocyst toxins in mice.  

PubMed

The neutralizing ability of commercially available antivenom prepared against 'milked' box-jellyfish (Chironex fleckeri) venom was tested intravenously in mice against crude nematocyst venom obtained by crushing isolated nematocysts and against each of two lethal toxins (T1 and T2) present in this venom. The in vitro neutralizing ability of the antivenom against crude venom was reduced markedly compared with its reported neutralizing ability against 'milked' venom whilst the in vivo neutralizing ability of the antivenom tested in both prophylactic and rescue experiments involving crude nematocyst venom was reduced approximately threefold. When tested in vitro and prophylactically in vivo the neutralizing ability of the antivenom was much more pronounced against T2 than against T1. This finding was in accord with the view that T1 was absent from the 'milked' venom against which the antivenom was prepared. Doses of crude venom in excess of twice the lethal dose killed mice within 2-3 min emphasizing the need for speed in the administration of antivenom. PMID:2903586

Endean, R; Sizemore, D J

1988-01-01

33

The in vivo cardiovascular effects of box jellyfish Chironex fleckeri venom in rats: efficacy of pre-treatment with antivenom, verapamil and magnesium sulphate.  

PubMed

Using a new technique to extract venom from the nematocysts, the efficacy of CSL box jellyfish antivenom (AV) and adjunct therapies, verapamil and magnesium sulfate (MgSO(4)), were investigated against the in vivo cardiovascular effects of Chironex fleckeri venom in anaesthetised rats. C. fleckeri venom (30 microg/kg; i.v.) produced a transient hypertensive response followed by hypotension and cardiovascular collapse within 4 min of administration. Prophylactic treatment of anaesthetised rats with CSL box jellyfish AV (3000 U/kg; i.v.) did not have any effect on the venom-induced pressor response, but prevented cardiovascular collapse in four out of 10 animals. Administration of verapamil (20mM@0.25 ml/min; i.v.) either alone or in combination with AV, did not have any effect on the C. fleckeri venom-induced pressor response nor the consequent hypotension or cardiovascular collapse of animals. However, the administration of verapamil negated the partially protective effects of AV. Concurrent artificial respiration of animals with the above treatments did not attenuate the C. fleckeri venom-induced cardiovascular effects. MgSO(4) (0.05-0.07M@0.25 ml/min; i.v.) alone did not have any effect on the venom-induced pressor response nor the consequent cardiovascular collapse of animals. However, although combined AV and MgSO(4) administration could not inhibit the transient pressor effect following the administration of C. fleckeri venom, it prevented cardiovascular collapse in all animals. We show for the first time, the cardiovascular effects of a C. fleckeri venom sample free of tentacular contamination and the potential of MgSO(4) as an adjunct therapy for the treatment of potentially fatal C. fleckeri envenomings. PMID:15109889

Ramasamy, Sharmaine; Isbister, Geoffrey K; Seymour, Jamie E; Hodgson, Wayne C

2004-05-01

34

Separation of two myotoxins from nematocysts of the box jellyfish (Chironex fleckeri).  

PubMed

Two myotoxins, both lethal to mice by i.v. injection, were obtained by chromatography on Sephadex G-200 of material released from isolated microbasic mastigophores of C. fleckeri. Both toxins elicit contractures of skeletal (diaphragm) musculature of the rat and of smooth (ileum and vas deferens) and atrial musculature of the guinea-pig, although consistent differences in the parameters of the contractures of each muscle type elicited by the two toxins are shown. Moreover, one toxin, with a molecular weight of approximately 150,000, also elicits activity on crustacean (barnacle) musculature, whilst the other toxin, with a molecular weight of approximately 600,000, elicits no activity in barnacle musculature at the concentrations tested. The toxins are labile when released from nematocysts and they lose all myotoxic activity within 3 days at 5 degrees C. They can also be isolated chromatographically from crude extracts of the contents of mixed nematocysts of C. fleckeri. They are considered to be the principal toxins injected by C. fleckeri during nematocyst discharge and appear to be different from the C. fleckeri toxins described by other workers. PMID:2887047

Endean, R

1987-01-01

35

An in vivo comparison of the efficacy of CSL box jellyfish antivenom with antibodies raised against nematocyst-derived Chironex fleckeri venom.  

PubMed

Although CSL box jellyfish antivenom (AV) remains the primary treatment for Chironex fleckeri envenoming, there has been considerable debate regarding its clinical effectiveness. Animal studies have shown that AV is largely ineffective in preventing C. fleckeri-induced cardiovascular collapse. This study examined the effectiveness of CSL box jellyfish AV (ovine IgG), raised against 'milked' venom, and polyclonal rabbit IgG antibodies (Ab) raised against nematocyst-derived venom. A venom dose of 30microg/kg, i.v., which causes an initial presser response (34+/-5mmHg; n=7) followed by cardiovascular collapse, was used in all experiments. A bolus dose of AV (3000U/kg, i.v.) or Ab (12mg; i.e. an equivalent protein 'load' to 3000U/kg AV), administered 15min prior to a bolus dose of venom, did not significantly attenuate the effects of venom. The venom response was also not significantly attenuated when AV (3000U/kg) was given as a bolus dose 10-60min prior to venom infusion. However, when the venom was incubated with either AV (3000U/kg) or Ab (12mg) for 3h prior to infusion, the effect of the venom was almost abolished. The results of this study demonstrate that antibodies raised against both 'milked' and nematocyst-derived venom are able to neutralise the cardiovascular collapse produced by the venom. However, large amounts of AV are required and must be preincubated with the venom to be protective. This indicates a very rapid action of the toxin(s) and that AV is unlikely to be clinically effective because it cannot be administered early enough. PMID:19429250

Winter, Kelly L; Isbister, Geoffrey K; Jacoby, Tamara; Seymour, Jamie E; Hodgson, Wayne C

2009-06-01

36

A functional comparison of the venom of three Australian jellyfish--Chironex fleckeri, Chiropsalmus sp., and Carybdea xaymacana--on cytosolic Ca2+, haemolysis and Artemia sp. lethality.  

PubMed

Cnidarian venoms produce a wide spectrum of envenoming syndromes in humans ranging from minor local irritation to death. Here, the effects of Chironex fleckeri, Chiropsalmus sp., and Carybdea xaymacana venoms on ventricular myocyte cytosolic Ca2+, haemolysis and Artemia sp. lethality are compared for the first time. All three venoms caused a large, irreversible elevation of cytosolic Ca2+ in myocytes as measured using the Ca2+ sensitive fluorescent probe Indo-1. The L-type Ca2+ channel antagonist verapamil had no effect on Ca2+ influx whilst La3+, a non-specific channel and pore blocker, inhibited the effect. Haemolytic activity was observed for all venoms, with C. xaymacana venom displaying the greatest activity. These activities are consistent with the presence of a pore-forming toxin existing in the venoms which has been demonstrated by transmission electron microscopy in the case of C. fleckeri. The venom of C. fleckeri was found to be more lethal against Artemia sp. than the venom of the other species, consistent with the order of known human toxicities. This suggests that the observed lytic effects may not underlie the lethal effects of the venom, and raises the question of how such potent activities are dealt with by envenomed humans. PMID:15626372

Bailey, Paul M; Bakker, Anthony J; Seymour, Jamie E; Wilce, Jacqueline A

2005-02-01

37

Verapamil potentiation of Chironex (box-jellyfish) antivenom.  

PubMed

'Rescue' experiments were performed on mice to compare the efficacy of i.v. verapamil, box-jellyfish antivenom, and a combination of both agents to counter the effects of toxic material extracted from the tentacles of Chironex fleckeri. In each of three series of experiments, four sets of mice were injected with doses of Chironex tentacle extracts containing approximately 4 mg/ml protein which were equivalent to twice the LD50. Three of these groups also received verapamil alone, antivenom alone, or a combination of both treatments. The combination therapy of drug and antivenom was superior to either agent alone. Treatment of verapamil alone appeared to be equivalent to that with only antivenom. PMID:1971128

Burnett, J W; Othman, I B; Endean, R; Fenner, P J; Callanan, V I; Williamson, J A

1990-01-01

38

Purification of Chironex fleckeri venom components using Chironex immunoaffinity chromatography.  

PubMed

A comparison of the purification of the nematocyst venom of Chironex fleckeri by affinity immunochromatography using 13 different monoclonal antibodies was made. Varying degrees of purification of mouse lethal factor, hemolysin and dermonecrotic factors, as well as antigen positive proteins were achieved with each of the monoclonal antibodies. Although the protein curves of the chromatography were similar, each of the monoclonal antibody columns had a distinctive pharmacological and SDS-PAGE profile. At least two hemolysins (120,000 and 70,000 molecular weight), two dermonecrotic principles (120,000, less than 120,000) and three lethal factors (120,000, 70,000 and 14,500 molecular weight) were detected. The degree to which aggregation and fragmentation affects the molecular weights of these proteins is not known. It appears that multiple pharmacological activities are present within the same molecule since it is only with great difficulty that a pharmacological activity can be assigned to a specific molecular weight. PMID:2900563

Naguib, A M; Bansal, J; Calton, G J; Burnett, J W

1988-01-01

39

Preliminary observations on the response of Chironex fleckeri (Cnidaria: Cubozoa: Chirodropida) to different colors of light.  

PubMed

Cubozoans are well known for their attraction to light and light-colored objects. Two highly venomous types are a public safety concern in Australian waters and elsewhere: Chironex fleckeri, long considered the world's deadliest animal and colloquially called the box jellyfish; and the irukandjis, a group of at least 10 species that cause various degrees of debilitating illness. We were asked by the tourism industry whether there might be a color of light that box jellyfish and irukandjis are not attracted to, such that nighttime diving activities might pose less risk of being stung. Our preliminary trials with Chironex fleckeri indicated a marked positive response to lights of white, red, yellow, green, orange, and blue. All colors elicited a strong and directed attraction to light; however, medusae slowed down their pulsation rate, streamed out their tentacles, and performed a series of figure-eight patterns back and forth through the lighted area when exposed to blue light, which we interpreted as feeding behavior. This compares curiously with a report subsequent to our testing, in which the small, mangrove-inhabiting cubomedusa Tripedalia cystophora and the beach-dwelling Chiropsella bronzie demonstrate a peak sensitivity to blue-green light in the region of 500 nm, and that the former is behaviorally attracted to blue and green light, but ignores red. This leaves open the possibility that Irukandji species, which are more closely related to Tripedalia than to Chironex, may be blind to red. PMID:18723637

Gershwin, Lisa-Ann; Dawes, Peter

2008-08-01

40

Venom and cnidome ontogeny of the cubomedusae Chironex fleckeri.  

PubMed

This is the first study to explore venom and cnidome variation of individual cubomedusae, Chironex fleckeri, of different ages and from different regional locations in relation to feeding ecology. As medusae matured the proportion of mastigophores (those nematocysts containing the lethal venom component) in the cnidome increased, along with proportion of the vertebrate toxic fraction, in the venom profile. This switch in cnidome and venom occurred at the seven to ten tentacle stage. Whole venom was found to be toxic specifically to vertebrate cardiac cells, as opposed to vertebrate skeletal cells, and dose dependent, along with the vertebrate toxic fraction. The venom and cnidome ontogeny, along with venom toxicity, is correlated with C. fleckeri's known feeding ecology. Large and mature C. fleckeri feed predominantly on vertebrates, and have a greater proportion of mastigophores in their cnidome along with more vertebrate toxic fraction in their venom, compared to when they are young and small feeding on invertebrates. PMID:23010166

McClounan, S; Seymour, J

2012-12-15

41

The in vitro vascular effects of two chirodropid (Chironex fleckeri and Chiropsella bronzie) venoms.  

PubMed

Clinical observations suggest a primary cardiotoxic role in fatal Chironex fleckeri stings. The limited research available indicates that Chiropsella bronzie venom acts in a similar manner although appears to be less potent. The aim of the present study was to elucidate the vascular effects of C. fleckeri and C. bronzie venoms using rat isolated aorta. Both venoms produced a sustained contraction of endothelium-denuded aorta which was not significantly affected by prazosin or box jellyfish antivenom. Felodipine significantly reduced the contractile response to C. fleckeri venom but not C. bronzie venom. Both venoms produced an initial relaxation (Phase 1), followed by a sustained contraction (Phase 2), in pre-contracted endothelium-intact aorta. Removal of the endothelium significantly inhibited both phases of the response. NOLA significantly inhibited Phase 1, but not Phase 2, of the response to both venoms. Atropine, HOE 140 or BQ 123 did not have any significant inhibitory effect on either phase. In conclusion, neither C. fleckeri nor C. bronzie venoms appear to contain components with activity at alpha(1)-adrenoceptors. Antivenom was ineffective in reversing the effects of the venom suggesting it is incapable of completely neutralising nematocyst-derived venom. Determining the mechanism of action of these venoms will allow for the development of better treatment strategies. PMID:17141433

Winter, Kelly L; Fernando, Ross; Ramasamy, Sharmaine; Seymour, Jamie E; Isbister, Geoffrey K; Hodgson, Wayne C

2007-01-10

42

The structure and function of the nematocysts of Chironex fleckeri Southcott, 1956.  

PubMed

Microbasic p-mastigophores, euryteles of two size groups, holotrichous isorhizas and atrichous isorhizas, comprise the cnidom of Chironex fleckeri, a cubozoan that has been responsible for several human fatalities. In its undischarged state each microbasic mastigophore of C. fleckeri consists of a capsule containing matrix and an inverted tube possessing a smooth-walled butt which is loosely coiled helically and which narrows to form a thread that is tightly coiled helically and markedly pleated. Both butt and thread carry three helices of spines and contain a granular matrix. During discharge, the proximal butt spines form initially a piercing stylet. Granular material from the butt and thread is released prior to the release of capsular material. Each eurytele possesses a tube with a butt composed of three bulbs, the middle bulb bearing long spines. Each holotrichous isorhiza possesses a coiled tube bearing small spines along its length. Each atrichous isorhiza exhibits a tube that is devoid of spines and loosely folded in the undischarged condition. The probable role of each type of nematocyst is inferred from its structure and features that enable the ready separation of the nematocysts of C. fleckeri from those of scyphozoan jellyfish are discussed. PMID:6138157

Rifkin, J; Endean, R

1983-01-01

43

Toxinological and immunological studies of capillary electrophoresis fractionated Chrysaora quinquecirrha (Desor) fishing tentacle and Chironex fleckeri Southcott nematocyst venoms.  

PubMed

Repeated runs of capillary electrophoresis (CE) were used to study partially-purified jellyfish nematocyst venom protein in concentrations sufficient to perform toxinological assays. Nematocyst venoms from Chironex fleckeri (Cf) and Chysaora quinquecirrha were processed. The CE eluate was divided into quadrants by scanning protein content. The fourth fraction of both jellyfish venoms, contained proteins with the smallest molecular weight components, which were responsible for the highest hemolysins and the humoral and cell-mediated immunological activity. Cytotoxic Cf lethal factor activity against human liver cells was widely dispersed throughout both venoms but more prominent in fraction 4. A V(beta) receptor human T-cell repertoire was not species-specific for either crude or fractionated jellyfish nematocyst venom. PMID:11166676

Bloom, D A; Radwan, F F; Burnett, J W

2001-01-01

44

A pharmacological and biochemical examination of the geographical variation of Chironex fleckeri venom.  

PubMed

Chironex fleckeri (box jellyfish) are found in the northern tropical waters of Australia. Although C. fleckeri have a wide geographical distribution and are able to swim large distances, adults tend to stay in small restricted areas. Clinical data shows that deaths from envenoming have not been recorded in Western Australia, yet numerous fatalities have occurred in Northern Territory and Queensland waters. One explanation for this discrepancy is a geographical variation in venom composition. This study examined the pharmacological and biochemical profiles of C. fleckeri venom from different geographical locations and seasons. Venoms were screened for cytotoxicity using a rat aortic smooth muscle cell line (A7r5). While all venoms caused concentration-dependent cytotoxicity, differences were seen in the potency of venoms from Mission Beach and Weipa, when collected in different seasons, as indicated by IC(50) values. Similarly venoms collected within the same season, from different locations around Australia, displayed marked differences in venom composition as shown by size exclusion HPLC and SDS-PAGE profiles which indicated the absence or reduced quantity of 'peaks' in some venoms. Based on IC(50) data obtained from the cell assay, the effects of the most potent (i.e. from Weipa in 2006) and the least potent (i.e. from Broome in 2007) venoms were examined in anesthetised rats. Both venoms at 10 microg/kg (i.v.) caused a transient hypertensive phase followed by cardiovascular collapse. However, at 4 microg/kg (i.v.) venom from Weipa 2006 caused a transient hypertensive phase followed by a transient decrease in MAP while venom from Broome 2007 only caused a small transient increase in MAP. This study demonstrates that there is considerable geographical variation in the composition of C. fleckeri venoms which is most distinct between specimens from western and eastern Australia and may explain the geographical variation in reported deaths. PMID:19945518

Winter, Kelly L; Isbister, Geoffrey K; McGowan, Sheena; Konstantakopoulos, Nicki; Seymour, Jamie E; Hodgson, Wayne C

2010-02-15

45

A pharmacological study of the toxin of a Cnidarian, Chironex fleckeri Southcott  

PubMed Central

1. A study has been made of the pharmacological actions of toxic preparations obtained from the box jellyfish Chironex fleckeri Southcott. Two toxin preparations were used. One was a tentacle extract which was partially purified by Sephadex gel filtration; the second was obtained by a process analogous to snake milking, and is probably similar in composition to the material injected into victims. 2. All preparations were extremely toxic; death in animals, following minimally lethal doses, occurred in minutes. Respiratory arrest of central origin appeared to be the terminal event in all species tested. This was accompanied by marked signs of cardiotoxicity. The heart was slowed, irregular, and showed varying degrees of conduction delay. Terminally it showed atrioventricular block. 3. Blood pressure changes were biphasic. An initial rise in carotid pressure was followed by a profound fall; a second rise to an above normal level frequently followed this. These blood pressure oscillations were damped down by prior treatment with hexamethonium but the hypertensive response remained. 4. Blood samples taken before terminal apnoea showed a variable degree of haemolysis and a raised K+ level. 5. Experiments with isolated organ preparations suggested that the toxin had a non-specific lytic effect on cells, but did not contain pharmacologically active substances of small molecular weight such as 5-hydroxytryptamine. 6. It is suggested that the toxin(s) act by altering membrane permeability; the signs at death may reflect the sensitivity of the target organs to such a change. ImagesFIG. 1. PMID:4390195

Freeman, Shirley E.; Turner, R. J.

1969-01-01

46

Partial purification of Chironex fleckeri (sea wasp) venom by immunochromatography with antivenom.  

PubMed

Chironex fleckeri crude venom was partially purified using immobilized commercially available ovoid antivenom. The antibody preparation reacted with lethal, hemolytic, dermonecrotic and mouse writhing (pain) factors in the crude venom. The lethal activity was purified five fold, while the specific eluate contained lower quantities of hemolytic, dermonecrotic and mouse writhing activities than did the crude venom. PMID:2872735

Calton, G J; Burnett, J W

1986-01-01

47

Nematocyst ratio and prey in two Australian cubomedusans, Chironex fleckeri and Chiropsalmus sp.  

PubMed

This study examined differences in the nematocyst ratios between two species of Australian cubozoans. In Chiropsalmus sp., a species that feeds exclusively on shrimp, no changes in the ratio of the three groups of nematocyst present in the cnidome were detected with size of the individual animals. In Chironex fleckeri, the ratio of different types of nematocysts in the cnidome for small animals (less than 40 mm) was similar to that of Chiropsalmus sp. However, with an increase in body size in C. fleckeri, the nematocyst ratio changed, with mastigophores (nematocysts believed to hold the lethal venom component for prey) increasing in proportion. The change in cnidome ratio is correlated with a change in the prey of C. fleckeri with increased size. Small C. fleckeri appeared to feed exclusively on prawns, medium sized animals fed on fish and prawns and large animals fed predominantly on fish. An increase in the proportion of mastigophores (and presumably the lethal venom component) in the cnidome of C. fleckeri may also be responsible for why this species has caused numerous human fatalities, while the Australian Chiropsalmus sp. has not. PMID:12419505

Carrette, T; Alderslade, P; Seymour, J

2002-11-01

48

In vitro effects on human heart and skeletal cells of the venom from two cubozoans, Chironex fleckeri and Carukia barnesi.  

PubMed

Although Chironex fleckeri and Carukia barnesi cause significant human envenomation, research into their effects in human models or human cells has been limited. In this in vitro study we have presented data that shows that although C. fleckeri is highly cytotoxic to human cardiac and skeletal muscle cells, C. barnesi is not cytotoxic at all concentrations tested to both cardiac and skeletal muscles cells. We also demonstrate that in vitro C. fleckeri venom cardiocytotoxic activity is significantly attenuated when heated to 44 °C for 20 min. There is a similar attenuation with skeletal cells at 46 °C. PMID:24176926

Pereira, Peter; Seymour, Jamie E

2013-12-15

49

Immunochromatographic purification of a nematocyst toxin from the cnidarian Chironex fleckeri (sea wasp).  

PubMed

A cardiotoxin from "milked venom" of the sea wasp (Chironex fleckeri) was purified by immunochromatography on an immobilized mouse monoclonal anti-Portuguese man-o'war (Physalia physalis) venom antibody column. The 20,000 molecular weight toxin caused bradycardia followed by cell lysis when applied to cultured chick embryonic cardiocytes at concentrations higher than 1.7 micrograms protein per ml and was lethal to mice at 0.04 micrograms protein per g. The toxin affected ion permeability in lipid bilayer membranes by forming monovalent cation channels. PMID:6084344

Olson, C E; Pockl, E E; Calton, G J; Burnett, J W

1984-01-01

50

Warmer waters in the Northern Territory--herald an earlier onset to the annual Chironex fleckeri Stinger season.  

PubMed

The discovery that Chironex fleckeri occurs annually in northern Australia occurred long ago, possibly before written records were available by local indigenous people, however, to date the precision of this yearly phenomenon is still not fully understood. Sea surface temperature (SST) appears to be a determining factor signaling the "arrival" of C. fleckeri each year. Anthropogenic climate change modeling predicts global rises in SST. Rises in SST may result in an earlier "arrival" of C. fleckeri during the dry season, possibly necessitating extension of the official Northern Territory stinger season to commence in September (currently October through to June). This short report presents data to support this hypothesis, facilitating policy makers with an environmental cue upon which changes to current stinger season can be based--prior to painful and potentially life-threatening presentations. PMID:20376549

Jacups, Susan P

2010-08-01

51

Australian venomous jellyfish, envenomation syndromes, toxins and therapy  

Microsoft Academic Search

The seas and oceans around Australia harbour numerous venomous jellyfish. Chironex fleckeri, the box jellyfish, is the most lethal causing rapid cardiorespiratory depression and although its venom has been characterised, its toxins remain to be identified. A moderately effective antivenom exists which is also partially effective against another chirodropid, Chiropsalmus sp. Numerous carybdeids, some unidentified, cause less severe illness, including

James Tibballs

2006-01-01

52

Jellyfish envenoming syndromes: unknown toxic mechanisms and unproven therapies.  

PubMed

Interest in envenoming syndromes caused by Australian jellyfish has been intense since the deaths in early 2002 of two tourists in Queensland, attributed to the Irukandji syndrome. We review current knowledge of these envenoming syndromes, mechanisms of venom action and therapy, focusing on the deadly box jellyfish, Chironex fleckeri, and the array of jellyfish thought to cause the Irukandji syndrome. Current understanding of jellyfish venom activity is very limited, and many treatments are unproven and based on anecdote. PMID:12492389

Bailey, Paul M; Little, Mark; Jelinek, George A; Wilce, Jacqueline A

2003-01-01

53

Cardiovascular effects of toxins isolated from the cnidarian Chironex fleckeri Southcott  

PubMed Central

1. Two unstable high molecular weight toxins have been isolated from tentacles of Chironex fleckeri by exclusion chromatography. Both are cardiotoxic; the lower molecular weight fraction is also a potent haemolysin. 2. Both toxins reduce the rate, amplitude of contraction and coronary flow in the isolated, perfused guinea-pig heart. Relative to the mouse lethal dose the haemolytic fraction is less potent in this preparation than the purely cardiotoxic fraction. 3. Both toxins cause a rise in arterial pressure in anaesthetized rats and rabbits by a direct action on the vascular musculature. This is followed by hypotension, bradycardia and cardiac irregularity. An increase in respiratory rate is followed by apnoea of variable duration, which is associated with a rise in arterial pressure. Animals frequently show arterial pressure oscillations with periods of apnoea interspersed with hyperpnoea. 4. The carotid occlusion reflex is depressed during hypotensive periods after both toxins, although (-)-noradrenaline can still elicit a marked pressor response. Bilateral cervical vagotomy has but little effect on the response to either toxin, save to prevent hyperpnoea, but radical denervation of sinoaortic afferents reduces the arterial pressure fall after the initial hypertensive response, suggesting that this fall is due to a combination of baroreceptor stimulation and a fall in cardiac output. Blood pressure oscillations are still seen, possibly due to central stimulation by hypercapnia. 5. Interference with the efferent arm of the vasomotor reflex arc with hexamethonium, bretylium or phenoxybenzamine either abolishes or markedly reduces the blood pressure oscillations without affecting the initial hypertensive response. 6. The cardiovascular effects of the two toxins are thought to be due to direct vasoconstriction, cardiotoxicity, baroreceptor stimulation and possibly depression of the vasomotor centre. The resultant disordering of the feed-back system regulating vasomotor tone leads to the characteristic arterial pressure oscillations. PMID:4396129

Freeman, Shirley E.; Turner, R. J.

1971-01-01

54

Exploring the therapeutic potential of jellyfish venom.  

PubMed

The venom of certain jellyfish has long been known to be potentially fatal to humans, but it is only recently that details of the proteomes of these fascinating creatures are emerging. The molecular contents of the nematocysts from several jellyfish species have now been analyzed using proteomic MS approaches and include the analysis of Chironex fleckeri, one of the most venomous jellyfish known. These studies suggest that some species contain toxins related to peptides and proteins found in other venomous creatures. The detailed characterization of jellyfish venom is likely to provide insight into the diversification of toxins and might be a valuable resource in drug design. PMID:25406009

Daly, Norelle L; Seymour, Jamie; Wilson, David

2014-10-01

55

Cutaneous light microscopic and ultrastructural changes in a fatal case of jellyfish envenomation.  

PubMed

A 5-year-old male suffered fatal envenomation from a jellyfish subsequently identified as Chironex fleckeri. Contact with the tentacles of the jellyfish had produced characteristic whiplash-like weals on the skin. At autopsy, skin from these areas was taken and later studied by light microscopy and electron microscopy. Both studies identified numerous nematocysts penetrating the epidermis and papillary dermis in the region of the sting. PMID:2903186

Strutton, G; Lumley, J

1988-08-01

56

The effect of vinegar on discharged nematocysts of Chironex fleckeri - Reply.  

PubMed

We thank Yanagihara and Chen for their comments and for the opportunity to further the discussion. Our statistician has re-examined (and reanalysed) these data, and we have supplied our data to an independent statistician (who supported our subsequent re-analysis) and are more than willing to supply these data to the journal editors should they feel this is necessary. Furthermore, the manuscript was independently reviewed by two reviewers who expressed no concern over our analysis. We are confident of our results. Yanagihara and Chen have incorrectly assumed that the errors displayed in Figure 2 are SEM. These errors represent the 95% confidence limits (CL) and as such their arguments are invalid. Furthermore, they outline that no statistical significance was provided for the specific W4 vs. W3 comparison. Although no specific statistics were displayed in the article, we do outline that LSD post hoc analysis was conducted and the means and 95% CL (as signified in Figure 2) that were significantly different were listed. This analysis showed that the percentage of venom discharged after the application of voltage (W2) and after the application of vinegar (W4) were significantly different from one another and both were significantly higher than either the initial before-voltage percentage (W1) or after the third washing (W3) after voltage application. It is further suggested that the samples used (W1 to W4) are internally matched samples and hence ANOVA is inappropriate. They suggest that a simple t-test would give different results. To alleviate their concerns, we have reanalysed the data using a paired t-test, comparing the level of protein present after the third washing (W3) since voltage was applied to the tentacle and the amount of protein present after vinegar was applied (W4). We paired each sample with itself (which effectively removes the issues surrounding analysis of internally matched samples). This analysis showed that the difference between the matched pairs was significant (t = 8.938, df = 2, P = 0.012). We further reanalysed these data comparing the mean protein expression after vinegar application (W4) to a standard value (23.2%) which was the mean percentage found after three washings (W3) post voltage application. Once again, the difference was found to be significant (t = 6.012, df = 2, P = 0.027). We would argue, however, that the use of t-tests, as suggested by Yanagihara and Chen, is inappropriate owing to a possible non-normal distribution of the data. To address this, we further analysed these data using a non-parametric median test to a binomial distribution for data collected after the third washing (W3) post voltage application and data collected after the application of vinegar (W4). We used a one-sample median test to a binomial. This statistical test is non-parametric as no assumption is made about the form of the population distribution except that it is continuous. This analysis once again revealed a significant difference between the treatments (Zb = 1.73, P = 0.04) and, as such, the amount of protein after vinegar application is greater than after the washing protocol; that is, the application of vinegar increases the amount of venom expressed. Finally, we have reanalysed our data using a Friedman's test (as suggested by another independent biostatistician consulted by the Editor) and once more found that the application of vinegar increased the presence of toxin (?2 = 9.0, df = 3, P = 0.029). We thank Yanagihara and Chen for pointing out an issue of the degrees of freedom listed. We realize there was a transcription error that was not identified by the authors within the proofs. Where it reads (F = 77.123x82), it should read (F = 77.123x8). Yanagihara and Chen have also expressed concerns about the press releases associated with this paper. We were contacted by the media as a result of the article's abstract release and the cover page of this journal for March 2014 with the heading "Does vinegar make box jellyfish stings worse?" Our sole press release (in response to the above

Welfare, Philippa; Little, Mark; Pereira, Peter; Seymour, Jamie

2014-09-01

57

Immunological and Toxinological Responses to Jellyfish Stings  

PubMed Central

Just over a century ago, animal responses to injections of jellyfish extracts unveiled the phenomenon of anaphylaxis. Yet, until very recently, understanding of jellyfish sting toxicity has remained limited. Upon contact, jellyfish stinging cells discharge complex venoms, through thousands of barbed tubules, into the skin resulting in painful and, potentially, lethal envenomations. This review examines the immunological and toxinological responses to stings by prominent species of jellyfish including Physalia sp. (Portuguese Man-o-War, Blue-bottle), Cubozoan jellyfish including Chironex fleckeri, several Carybdeids including Carybdea arborifera and Alatina moseri, Linuche unguiculta (Thimble jellyfish), a jellyfish responsible for Irukandji syndrome (Carukia barnesi) and Pelagia noctiluca. Jellyfish venoms are composed of potent proteinaceous porins (cellular membrane pore-forming toxins), neurotoxic peptides, bioactive lipids and other small molecules whilst the tubules contain ancient collagens and chitins. We postulate that immunologically, both tubular structural and functional biopolymers as well as venom components can initiate innate, adaptive, as well as immediate and delayed hypersensitivity reactions that may be amenable to topical anti-inflammatory-immunomodifier therapy. The current challenge for immunotoxinologists is to deconstruct the actions of venom components to target therapeutic modalities for sting treatment. PMID:21824077

Tibballs, James; Yanagihara, Angel A.; Turner, Helen C.; Winkel, Ken

2013-01-01

58

Immunological and toxinological responses to jellyfish stings.  

PubMed

Just over a century ago, animal responses to injections of jellyfish extracts unveiled the phenomenon of anaphylaxis. Yet, until very recently, understanding of jellyfish sting toxicity has remained limited. Upon contact, jellyfish stinging cells discharge complex venoms, through thousands of barbed tubules, into the skin resulting in painful and, potentially, lethal envenomations. This review examines the immunological and toxinological responses to stings by prominent species of jellyfish including Physalia sp (Portuguese Man-o-War, Blue-bottle), Cubozoan jellyfish including Chironex fleckeri, several Carybdeids including Carybdea arborifera and Alatina moseri, Linuche unguiculta (Thimble jellyfish), a jellyfish responsible for Irukandji syndrome (Carukia barnesi) and Pelagia noctiluca. Jellyfish venoms are composed of potent proteinaceous porins (cellular membrane pore-forming toxins), neurotoxic peptides, bioactive lipids and other small molecules whilst the tubules contain ancient collagens and chitins. We postulate that immunologically, both tubular structural and functional biopolymers as well as venom components can initiate innate, adaptive, as well as immediate and delayed hypersensitivity reactions that may be amenable to topical anti-inflammatory-immunomodifier therapy. The current challenge for immunotoxinologists is to deconstruct the actions of venom components to target therapeutic modalities for sting treatment. PMID:21824077

Tibballs, James; Yanagihara, Angel A; Turner, Helen C; Winkel, Ken

2011-10-01

59

First aid treatment of jellyfish stings in Australia. Response to a newly differentiated species.  

PubMed

Vinegar has been shown to inhibit neomatocyst discharge in Chironex fleckeri, the deadly north Australian box-jellyfish, and application of vinegar has become accepted first aid, not only for box-jellyfish stings, but also for stings by other Australian jellyfish. However, in a newly differentiated species of Physalia in Australian waters, which causes severe envenomation, vinegar was found to cause discharge in up to 30% of neomatocysts. In treating these stings, the use of vinegar is not recommended as it may increase envenomation. Stings from the single-tentacled Physalia utriculus (the "bluebottle") are not severe, tentacles with unfired nematocysts rarely adhere to the victim's skin and vinegar dousing is not required. Vinegar treatment is therefore an unnecessary step in the first aid management of any Physalia sting but remains an essential first aid treatment for all cubozoan (box) jellyfish tested to date. PMID:8469205

Fenner, P J; Williamson, J A; Burnett, J W; Rifkin, J

1993-04-01

60

Variation in lethality and effects of two Australian chirodropid jellyfish venoms in fish.  

PubMed

The North Queensland chirodropid box jellyfish Chironex fleckeri and Chiropsalmus sp. share similar nematocyst composition and the same prey of Acetes australis shrimps in their early medusa stages; however, as C. fleckeri individuals reach larger size, the animals add fish to their diet and their complement of nematocyst types changes, allowing larger doses of venom to be delivered to prey. This study demonstrated that the venoms of the two species differ as well: despite similar effects previously documented in crustacean prey models, the two had widely different cardiac and lethal effects in fish, with C. fleckeri being substantially more potent in its ability to cause death. Comparisons between the venom delivery abilities of the two species showed that the change in nematocysts of C. fleckeri cannot alone account for its ontogenetic shift to prey fish; instead, its prey ecology clearly necessitates it having venom capable of acting efficiently to cause death in fish. Although this venom is almost certainly produced at greater metabolic cost to the animal than the less-lethal venom of Chiropsalmus sp., owing to its greater molecular protein complexity, it confers the advantage of increased caloric intake from fish prey, facilitating larger size and potentially greater reproductive output of C. fleckeri over Chiropsalmus sp. PMID:16165181

Kintner, Anna H; Seymour, Jamie E; Edwards, Susan L

2005-11-01

61

Successful use of Chironex antivenom by members of the Queensland Ambulance Transport Brigade.  

PubMed

We report the first administration in Australia by ambulance officers of the Commonwealth Serum Laboratories' Chironex fleckeri antivenom, in two separate, major, potentially life-threatening Chironex envenomations. In both cases, the antivenom was effective in helping to relieve signs and symptoms (including pain). This antivenom still is the most specific part of the treatment of a major Chironex fleckeri sting after stabilization of the airway, breathing and circulation. The additional use of verapamil may contribute to the prevention of some of the cardiac complications that result from the direct effects of the Chironex venom. PMID:2574410

Fenner, P J; Williamson, J A; Blenkin, J A

62

First record of association of copepods with highly venomous box jellyfish chironex, with description of new species of paramacrochiron (cyclopoida: macrochironidae).  

PubMed

Paramacrochiron chironecicola n. sp. (Copepoda: Cyclopoida: Macrochironidae) is described from the highly venomous box jellyfish Chironex sp. collected from Malampaya Sound, Palawan Island, The Philippines. This is the first record of copepods associated with cubozoan medusae, although other cnidarian groups such scyphozoans, hydrozoans, and anthozoans are common hosts for symbiotic copepods. The infection sites were on the subumbrella, pedalium, and rhopalium, but also rarely on the adradial furrow. The new species is distinguished from other congeners by a combination of the following features: (1) the fifth pedigerous somite dorsally covering the anterior part of the female genital double-somite; (2) the fine structures of the antenna (relative lengths of segments) and maxilliped (positions of terminal elements) of the female; (3) the relatively long outer spines on the exopodal segments of legs 1-4; (4) the relatively long and thick female leg 5 bearing a long protopodal seta which reaches to the distal margin of the exopod; (5) the relatively short caudal ramus in the female; and (6) the plump prosome and short urosome in the male. Since members of the genus typically parasitize scyphozoans, especially rhizostomes, the association of this parasitic copepod on cubozoans may reflect the relatively close phylogenetic relationship between cubozoans and scyphozoans. PMID:25826070

Ohtsuka, Susumu; Metillo, Ephrime; Boxshall, Geoffrey A

2015-04-01

63

Dose and time dependence of box jellyfish antivenom  

PubMed Central

Background The effectiveness of the currently available box jellyfish (Chironex fleckeri) antivenom has been subject of debate for many years. To assess whether the box jellyfish antivenom has the ability to attenuate venom-induced damage at cellular level, the present study analyzed the dose and time dependence of the antivenom in a cell-based assay. Methods Different doses of antivenom were added to venom and subsequently administered to cells and the cell index was measured using xCelligence Technology (ACEA Biosciences). Similarly, antivenom and venom were incubated over different time periods and cell survival measured as stated above. For both experiments, the cell index was plotted as a measure of cell survival against the dose or incubation time and significance was determined with the use of a one-way ANOVA with a LSD post hoc test. Results Increasing concentrations of antivenom significantly augmented cell survival, with a concentration of approximately five times the currently recommended dose for human envenomation, causing the first significant increase in cell survival compared venom alone. Further, cell survival improved with increasing incubation time of venom and antivenom prior to addition to the cells, indicating that box jellyfish antivenom requires approximately 70 minutes to neutralize C. fleckeri venom. Conclusion The presented results suggest that the currently recommended dose of antivenom requires adjustment, and more importantly, a human trial to test the effects of higher concentrations is also necessary. Further, antivenom has delayed neutralizing effects (i.e. after 70 minutes) which underlines the eminence of immediate and prolonged cardiopulmonary resuscitation in victims suffering from a C. fleckeri venom-induced cardiovascular collapse. PMID:25161664

2014-01-01

64

The in vivo cardiovascular effects of an Australasian box jellyfish (Chiropsalmus sp.) venom in rats.  

PubMed

Using a new technique to extract venom from the nematocysts of jellyfish, the in vivo cardiovascular effects of Chiropsalmus sp. venom were investigated in anaesthetized rats. Chiropsalmus sp. venom (150 microg/kg, i.v.) produced a transient hypertensive response (44+/-4 mmHg; n=6) followed by hypotension and cardiovascular collapse. Concurrent artificial respiration or pretreatment with Chironex fleckeri antivenom (AV, 3000 U/kg, i.v.) did not have any effect on the venom-induced hypertensive response nor the subsequent cardiovascular collapse. The cardiovascular response of animals receiving venom after the infusion of MgSO4 (50-70 mM @ 0.25 ml/min, i.v.; n=5) alone, or in combination with AV (n=5), was not significantly different from rats receiving venom alone. Prior administration of prazosin (50 microg/kg, i.v.; n=4) or ketanserin (1 mg/kg, i.v.; n=4) did not significantly attenuate the hypertensive response nor prevent the cardiovascular collapse induced by venom (50 microg/kg, i.v.). In contrast to previous work examining C. fleckeri venom, administration of AV alone, or in combination with MgSO4, was not effective in preventing cardiovascular collapse following the administration of Chiropsalmus sp. venom. This indicates that the venom of the two related box jellyfish contain different lethal components and highlights the importance of species identification prior to initiating treatment regimes following jellyfish envenoming. PMID:15683870

Ramasamy, Sharmaine; Isbister, Geoffrey K; Seymour, Jamie E; Hodgson, Wayne C

2005-03-01

65

Autonomic neurotoxicity of jellyfish and marine animal venoms.  

PubMed

Venoms and poisons of jellyfish and other marine animals can induce damage to the human nervous and circulatory systems. Clues to the pathogenesis and clinical manifestations of these lesions can be obtained from data of human envenomations and animal experimentation. Because many investigators are unaware that marine animal venoms have autonomic actions, this paper aims to elucidate the broad antagonistic or toxic effects these compounds have on the autonomic nervous system. Marine venoms can affect ion transport of particularly sodium and calcium, induce channels or pores in neural and muscular cellular membranes, alter intracellular membranes of organelles and release mediators of inflammation. The box jellyfish, particularly Chironex fleckeri, in the Indo-Pacific region, is the world's most venomous marine animal and is responsible for autonomic disorders in patients. The symptoms induced by these venoms are vasospasm, cardiac irregularities, peripheral neuropathy, aphonia, ophthalmic abnormalities and parasympathetic dysautonomia. Cases of Irukandji syndrome, caused by the jellyfish Carukia barnesi, have symptoms that mimic excessive catecholamine release. Coelenterate venoms can also target the myocardium, Purkinje fiber, A-V node or aortic ring. Actions on nerves, as well as skeletal, smooth or cardiac muscle occur. Recent studies indicate that the hepatic P-450 enzyme family may be injured by these compounds. The multiplicity of these venom activities means that a thorough understanding of the sting pathogenesis will be essential in devising effective therapies. PMID:9613803

Burnett, J W; Weinrich, D; Williamson, J A; Fenner, P J; Lutz, L L; Bloom, D A

1998-04-01

66

Australian venomous jellyfish, envenomation syndromes, toxins and therapy.  

PubMed

The seas and oceans around Australia harbour numerous venomous jellyfish. Chironex fleckeri, the box jellyfish, is the most lethal causing rapid cardiorespiratory depression and although its venom has been characterised, its toxins remain to be identified. A moderately effective antivenom exists which is also partially effective against another chirodropid, Chiropsalmus sp. Numerous carybdeids, some unidentified, cause less severe illness, including Carybdea rastoni whose toxins CrTX-A and CrTX-B are large proteins. Carukia barnesi, another small carybdeid is one cause of the 'Irukandji' syndrome which includes delayed pain from severe muscle cramping, vomiting, anxiety, restlessness, sweating and prostration, and occasionally severe hypertension and acute cardiac failure. The syndrome is in part caused by release of catecholamines but the cause of heart failure is undefined. The venom contains a sodium channel modulator. Two species of Physalia are present and although one is potentially lethal, has not caused death in Australian waters. Other significant genera of jellyfish include Tamoya, Pelagia, Cyanea, Aurelia and Chyrosaora. PMID:16928389

Tibballs, James

2006-12-01

67

The Jellyfish hunter--Jack Barnes: a pioneer medical toxinologist in Australia.  

PubMed

Dr Jack Handyside Barnes (1922-1985) was one of the small and elite group of Pacific marine toxinologists whose work was characterised by an uncompromising rugged persona, a focussed resolve to solve challenging problems of human clinical envenomation, and who conducted curiosity-driven research under conditions of scientific isolation. He was a pioneering advocate for the preservation of marine heritage, particularly that of the Great Barrier Reef. A former military commando who later became a general medical practitioner with extensive surgical and obstetric skills, in 1947 he was appointed the Medical Superintendent of Thursday Island in the Torres Strait. Later (from January 1953), he worked indefatigably as a general medical practitioner in Cairns, in tropical North Australia. For four decades (1945-1985), Jack Barnes undertook detailed laboratory, clinical and field research into invertebrate envenomation, particularly medusan toxinology. In 1960 he discovered the species responsible for the Irukandji syndrome, a small carybdeid named Carukia barnesi in his honour. He invented the research technique for the extraction of venom from the world's most venomous creature, the Pacific box Jellyfish, Chironex fleckeri. By 1960, he had published taxonomic details of nematocyst structure and clinical envenomation details consequent upon stings by Physalia, Cyanea, Chironex, Chiropsalmus and Carukia. This paper is a précis of the chronology of his life, contributions and influence. PMID:17070882

Pearn, John; Fenner, Peter

2006-12-01

68

Is sleep's 'supreme mystery' unraveling? An evolutionary analysis of sleep encounters no mystery; nor does life's earliest sleep, recently discovered in jellyfish.  

PubMed

Biotelemetry has revealed daily 15-h behavioral sleep periods in a cubomedusan jellyfish, Chironex fleckeri. Its sleep is expected to be phylogenetically most primitive, since jellyfish possess only two germ layers. They belong to the phylum Cnidaria, the 'simplest' multicellular organisms with an organized nervous system. Cubomedusae have a complex visual system with 24 eyes of four different types, each type specialized for a different task. Input to these eyes during visually guided fast-swimming predation requires enormous amounts of neural processing, possibly nearly saturating the capacity of their comparatively simple nervous system. These heavy neural demands may account for the need for fifteen hours of sleep. C. fleckeri is the only animal known for which sleep may be either present or absent, dependent on lifestyle. Limited knowledge of behavior of some other cubomedusae suggests that they also possess this faculty. The finding of sleep in C. fleckeri supports current proposals of sleep's origin and basic function. Evolutionary analyses link sleep to a conflict produced by excessive processing demands on multifunctional neural circuitry for detailed focal vision by complex lensed eyes. The conflict arises between the enormous demands of complex visual analysis and needs for split-second control of actions, on the one hand, and non-urgent processing of memories of ongoing and stored events, on the other. Conflict is resolved by deferring the non-urgent processing to periods of sleep. Without sleep, selection would favor the evolution of circuitry 'dedicated' to single or but few tasks, with corresponding lesser efficiency. Had complex lensed eyes of medusae originated as a consequence of selection for increased mating success of males pursuing females, it could have occurred before the evolution of fast-swimming bilateral (three-germ-layered) prey. But if it was a consequence of selection for increased prey-hunting success, the origin of such eyes probably awaited the coexistence of bilateral prey. PMID:16213664

Kavanau, J Lee

2006-01-01

69

The pharmacology of Malo maxima jellyfish venom extract in isolated cardiovascular tissues: A probable cause of the Irukandji syndrome in Western Australia.  

PubMed

The in vitro cardiac and vascular pharmacology of Malo maxima, a newly described jellyfish suspected of causing Irukandji syndrome in the Broome region of Western Australia, was investigated in rat tissues. In left atria, M. maxima crude venom extract (CVE; 1-100?g/mL) caused concentration-dependent inotropic responses which were unaffected by atropine (1?M), but significantly attenuated by tetrodotoxin (TTX; 0.1?M), propranolol (1?M), Mg(2+) (6mM) or calcitonin gene-related peptide antagonist (CGRP(8-37); 1?M). CVE caused no change in right atrial rate until 100?g/mL, which elicited bradycardia. This was unaffected by atropine, TTX, propranolol or CGRP(8-37). In the presence of Mg(2+), CVE 30-100?g/mL caused tachycardia. In small mesenteric arteries CVE caused concentration-dependent contractions (pEC(50) 1.03±0.07?g/mL) that were unaffected by prazosin (0.3?M), ?-conotoxin GVIA (0.1?M) or Mg(2+) (6mM). There was a 2-fold increase in sensitivity in the presence of CGRP(8-37) (3?M). TTX (0.1?M), box jellyfish Chironex fleckeri antivenom (92.6U/mL) and benextramine (3?M) decreased sensitivity by 2.6, 1.9 and 2.1-fold, respectively. CVE-induced maximum contractions were attenuated by C. fleckeri antivenom (-22%) or benextramine (-49%). M. maxima CVE appears to activate the sympathetic, but not parasympathetic, nervous system and to stimulate sensory nerve CGRP release in left atria and resistance arteries. These effects are consistent with the catecholamine excess thought to cause Irukandji syndrome, with additional actions of CGRP release. PMID:21237252

Li, Ran; Wright, Christine E; Winkel, Kenneth D; Gershwin, Lisa-Ann; Angus, James A

2011-03-25

70

JELLYFISH BLOOMS The growth of jellyfishes  

E-print Network

JELLYFISH BLOOMS The growth of jellyfishes M. L. D. Palomares Æ D. Pauly Published online: 15 and methods have been used to study the growth of jellyfish, with the result that few generalities have that this situation can be overcome by length-frequency analysis (LFA), applied to jellyfish bell diameter (i

Pauly, Daniel

71

Jellyfish Stings, First Aid  

MedlinePLUS

newsletter | contact Share | Jellyfish Stings, First Aid A A A The rash caused by a jellyfish sting is often red and swollen, and it may even bleed. First Aid Guide Jellyfish are aquatic invertebrates that can sting people who ...

72

Cardiovascular actions of the venom from the Irukandji (Carukia barnesi) jellyfish: effects in human, rat and guinea-pig tissues in vitro and in pigs in vitro.  

PubMed

1. We have investigated the cardiovascular pharmacology of the crude venom extract (CVE) from the potentially lethal, very small carybdeid jellyfish Carukia barnesi, in rat, guinea-pig and human isolated tissues and anaesthetized piglets. 2. In rat and guinea-pig isolated right atria, CVE (0.1-10 microg/mL) caused tachycardia in the presence of atropine (1 micromol/L), a response almost completely abolished by pretreatment with tetrodotoxin (TTX; 0.1 micromol/L). In paced left atria from guinea-pig or rat, CVE (0.1-3 microg/mL) caused a positive inotropic response in the presence of atropine (1 micromol/L). 3. In rat mesenteric small arteries, CVE (0.1-30 microg/mL) caused concentration-dependent contractions that were unaffected by 0.1 micromol/L TTX, 0.3 micromol/L prazosin or 0.1 micromol/L omega-conotoxin GVIA. 4. Neither the rat right atria tachycardic response nor the contraction of rat mesenteric arteries to CVE were affected by the presence of box jellyfish (Chironex fleckeri) antivenom (92.6 units/mL). 5. In human isolated driven right atrial trabeculae muscle strips, CVE (10 microg/mL) tended to cause an initial fall, followed by a more sustained increase, in contractile force. In the presence of atropine (1 micromol/L), CVE only caused a positive inotropic response. In separate experiments in the presence of propranolol (0.2 micromol/L), the negative inotropic effect of CVE was enhanced, whereas the positive inotropic response was markedly decreased. 6. In anaesthetized piglets, CVE (67 microg/kg, i.v.) caused sustained tachycardia and systemic and pulmonary hypertension. Venous blood samples demonstrated a marked elevation in circulating levels of noradrenaline and adrenaline. 7. We conclude that C. barnesi venom may contain a neural sodium channel activator (blocked by TTX) that, in isolated atrial tissue (and in vivo), causes the release of transmitter (and circulating) catecholamines. The venom may also contain a 'direct' vasoconstrictor component. These observations explain, at least in part, the clinical features of the potentially deadly Irukandji syndrome. PMID:16173936

Winkel, Kenneth D; Tibballs, James; Molenaar, Peter; Lambert, Gavin; Coles, Peter; Ross-Smith, Mark; Wiltshire, Carolyn; Fenner, Peter J; Gershwin, Lisa-Ann; Hawdon, Gabrielle M; Wright, Christine E; Angus, James A

2005-09-01

73

Jellyfish Gone Wild  

NSDL National Science Digital Library

Since the 1980s, worldwide jellyfish blooms have caused hundreds of millions--or perhaps even billions--of dollars in losses. Worldwide reports of massive jellyfish blooms are triggering speculation that jellyfish swarms are increasing because of human activities. But are they? This report--which is guaranteed to make your skin crawl--explains the basics of jellyfish biology and what scientists have thus far discovered about the causes and future of jellyfish blooms.

74

Reversible parasympathetic dysautonomia following stinging attributed to the box jelly fish (Chironex fleckeri).  

PubMed

Following a box jelly fish sting, a 52 year old Chinese fisherman developed acute abdominal distension, inability to pass urine and failure of erection. Examination revealed gaseous abdominal distension and a distended urinary bladder. Absence of lachrimation and absence of changes in the R-R interval in the ECG during breathing and carotid sinus massage gave further evidence of parasympathetic dysautonomia. The patient made a complete recovery. The case highlights the occurrence of reversible parasympathetic dysautonomia following box jelly fish sting. PMID:6152151

Chand, R P; Selliah, K

1984-10-01

75

Jiggling Jellyfish Grade Level: Fifth  

E-print Network

Jiggling Jellyfish Grade Level: Fifth Developers: Kim Banta, Steve Heyer, Shari Main (teachers jellyfish data accurately !" Analyze data to answer questions Oregon State Science Standards addressed. Material list for the unit: !" Thermometers !" Salinity gauges (constructed by students) !" Jellyfish nets

76

Jellyfish as food  

Microsoft Academic Search

Jellyfish have been exploited commercially by Chinese as an important food for more than a thousand years. Semi-dried jellyfish represent a multi-million dollar seafood business in Asia. Traditional processing methods involve a multi-phase processing procedure using a mixture of salt (NaCl) and alum (AlK[SO4]2c12 H2O) to reduce the water content, decrease the pH, and firm the texture. Processed jellyfish have

Y. H. Peggy Hsieh; Fui-Ming Leong; Jack Rudloe

2001-01-01

77

JELLYFISH BLOOMS Increasing jellyfish populations: trends in Large Marine  

E-print Network

JELLYFISH BLOOMS Increasing jellyfish populations: trends in Large Marine Ecosystems Lucas Brotz there are various indications and claims that jellyfish (i.e., scyphozoans, cubozoans, most hydrozoans, ctenophores never been pre- sented. Because this is mainly due to scarcity of quantitative time series of jellyfish

Pauly, Daniel

78

Venomous pelagic coelenterates: chemistry, toxicology, immunology and treatment of their stings.  

PubMed

Ten years have elapsed since our last review article on the toxicology of venomous pelagic coelenterates was published (Burnett and Calton, 1977). Investigation on important medusae and the chemistry of their nematocyst venoms have been expanding. The venomous jellyfish discussed here include the Portuguese man-o'war, (Physalia physalis), the sea nettle (Chrysaora quinquecirrha), the box jellyfish (Chironex fleckeri and/or Chiropsalmus quadrigatus), the cabbage head jellyfish (Stomolophus meleagris), the lion's mane jellyfish (Cyanea capillata), the Irukandji jellyfish (Carukia barnesi), the Moreton Bay Carybdeid medusa (Morbakka), and the mauve blubber (Pelagia noctiluca). PMID:2888220

Burnett, J W; Calton, G J

1987-01-01

79

COLUMBIA SCIENCE REVIEW Jellyfish Takeover  

E-print Network

COLUMBIA SCIENCE REVIEW Jellyfish Takeover A Fundamental Change in the Food chain? The Science First Impressions and Snap Decisions Exoplanets 04 06 09 10 12 14 26 12 20 6 Jellyfish Takeover? Is More 30 Graphene I Thought There Were Only Resistors... Jellyfish Takeover? Brains, Games, and Mainframes

Qian, Ning

80

Jellyfish fisheries in southeast Asia  

Microsoft Academic Search

A few large jellyfish species in the order Rhizostomeae constitute an important food in Chinese cooking. For more than 1700 years, they have been exploited along the coasts of China. Such jellyfish became an important fishery commodity of Southeast Asian countries in the 1970s with increasing demand from the Japanese market. Recently, Japan has imported 5400–10?000 tons of jellyfish products

Makoto Omori; Eiji Nakano

2001-01-01

81

Pharmacological effects of various venoms on cutaneous capillary leakage.  

PubMed

Studies to counteract the cutaneous vasopermeability actions of a wasp (Vespa orientalis), an anemone (Bolocera tuediae) and three jellyfish (Chironex fleckeri, Chrysaora quinquecirrha and Physalia physalis) venoms were conducted by using various pharmacological antagonists. Piripost (a leukotriene inhibitor) reduced vasopermeability if administered 5 min prior to challenge with the jellyfish venoms. Methysergide counteracted the vasopermeability of three of four coelenterate venoms, whereas indomethacin was effective against capillary leakage induced by Chironex venom. These studies indicate that anti-dermonecrotic therapy against various venoms will have to be species-specific. PMID:2875548

Burnett, J W; Calton, G J

1986-01-01

82

Jellyfish: Networking Data Centers Randomly  

E-print Network

Industry experience indicates that the ability to incrementally expand data centers is essential. However, existing high-bandwidth network designs have rigid structure that interferes with incremental expansion. We present Jellyfish, a high-capacity network interconnect, which, by adopting a random graph topology, yields itself naturally to incremental expansion. Somewhat surprisingly, Jellyfish is more cost-efficient than a fat-tree: A Jellyfish interconnect built using the same equipment as a fat-tree, supports as many as 25% more servers at full capacity at the scale of a few thousand nodes, and this advantage improves with scale. Jellyfish also allows great flexibility in building networks with different degrees of oversubscription. However, Jellyfish's unstructured design brings new challenges in routing, physical layout, and wiring. We describe and evaluate approaches that resolve these challenges effectively, indicating that Jellyfish could be deployed in today's data centers.

Singla, Ankit; Popa, Lucian; Godfrey, P Brighten

2011-01-01

83

Are Jellyfish Populations Increasing Worldwide Rachel Chudnow  

E-print Network

Are Jellyfish Populations Increasing Worldwide (and Why?) By Rachel Chudnow Submitted in partial of jellyfish Figure 2. Map of systems used for analysis of jellyfish population trends and correlations between jellyfish abundance and possible variables causing observed change. Figure 3. Interannual variation

Worm, Boris

84

Prediction of an Epitope-based Computational Vaccine Strategy for Gaining Concurrent Immunization Against the Venom Proteins of Australian Box Jellyfish  

PubMed Central

Background: Australian Box Jellyfish (C. fleckeri) has the most rapid acting venom known to in the arena of toxicological research and is capable enough of killing a person in less than 5 minutes inflicting painful, debilitating and potentially life-threatening stings in humans. It has been understood that C. fleckeri venom proteins CfTX-1, 2 and HSP70-1 contain cardiotoxic, neurotoxic and highly dermatonecrotic components that can cause itchy bumpy rash and cardiac arrest. Subjects and Methods: As there is no effective drug available, novel approaches regarding epitope prediction for vaccine development were performed in this study. Peptide fragments as nonamers of these antigenic venom proteins were analyzed by using computational tools that would elicit humoral and cell mediated immunity, were focused for attempting vaccine design. By ranking the peptides according to their proteasomal cleavage sites, TAP scores and IC50<250 nM, the predictions were scrutinized. Furthermore, the epitope sequences were examined by in silico docking simulation with different specific HLA receptors. Results: Interestingly, to our knowledge, this is the maiden hypothetical immunization that predicts the promiscuous epitopes with potential contributions to the tailored design of improved safe and effective vaccines against antigenic venom proteins of C. fleckeri which would be effective especially for the Australian population. Conclusion: Although the computational approaches executed here are based on concrete confidence which demands more validation and in vivo experiments to validate such in silico approach. PMID:24403734

Alam, Md. Jibran; Ashraf, Kutub Uddin Muhammad

2013-01-01

85

Immunostimulation effect of jellyfish collagen.  

PubMed

Certain edible large jellyfishes belonging to the order Rhizostomeae are consumed in large quantities in China and Japan. The exumbrella part of the edible jellyfish Stomolophus nomurai was cut and soaked in dilute hydrochloric acid solution (pH 3.0) for 12 h, and heated at 121 degrees C for 20 min. The immunostimulation effects of the jellyfish extract were examined. The jellyfish extract enhanced IgM production of human hybridoma HB4C5 cells 34-fold. IgM and IgG production of human peripheral blood lymphocytes (PBL) were also accelerated, 2.8- and 1.4-fold respectively. Moreover, production of interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha by human PBL was stimulated 100- and 17-fold respectively. Collagenase treatment inactivated the immunostimulation activity of the jellyfish extract. In addition, purified collagen from bovine Achilles' tendon accelerated IgM production of hybridoma cells. These facts mean that collagen has an immunostimulation effect, and that the active substance in jellyfish extract is collagen. PMID:16960386

Sugahara, Takuya; Ueno, Masashi; Goto, Yoko; Shiraishi, Ryusuke; Doi, Mikiharu; Akiyama, Koichi; Yamauchi, Satoshi

2006-09-01

86

The jellyfish joyride: causes, consequences and management  

E-print Network

The jellyfish joyride: causes, consequences and management responses to a more gelatinous future, eutrophication, climate change, translocation and habitat modification appear to be promoting jellyfish (pelagic jellyfish in check through competition or predation) to a less desirable gelatinous state, with lasting

Hays, Graeme

87

Finding a Dense-Core in Jellyfish graphs Udi Weinsberg  

E-print Network

Finding a Dense-Core in Jellyfish graphs Mira Gonen Dana Ron Udi Weinsberg Avishai Wool§ Abstract to have coined the "jellyfish" term. The authors argued that the Internet topology resembles a jellyfish

Ron, Dana

88

Jellyfish populations in the Mediterranean Sea  

E-print Network

Knowledge of jellyfish populations in the Mediterranean Sea is rather extensive, due to a combination of long-term datasets and interest relating to impacts on human activities. The notorious jellyfish Pelagia noctiluca appears to be blooming with increased frequency in some areas, and may sting tens of thousands of sea bathers in a single year. In addition, a number of invasive species of jellyfish appear to be thriving in the Mediterranean, some of which have significant impacts on fishing and other industries. In contrast, other groups of jellyfish show variable trends over time, and may be of little interest to the public. Here, we summarize knowledge of jellyfish in the Mediterranean Sea, including temporal trends for a variety of species, and discuss possible anthropogenic causes of increased jellyfish abundance and management interventions in the face of uncertainty.

Lucas Brotz; Daniel Pauly

89

Dangerous jellyfish blooms are predictable.  

PubMed

The potentially fatal Irukandji syndrome is relatively common in tropical waters throughout the world. It is caused by the sting of the Irukandji jellyfish, a family of box jellyfish that are almost impossible to detect in the water owing to their small size and transparency. Using collated medical records of stings and local weather conditions, we show that the presence of Irukandji blooms in coastal waters can be forecast on the basis of wind conditions. On the Great Barrier Reef, blooms largely coincide with relaxation of the prevailing southeasterly trade winds, with average conditions corresponding to near zero alongshore wind on the day prior to the sting. These conditions are consistent with hypotheses long held by local communities and provide a basis for designing management interventions that have the potential to eliminate the majority of stings. PMID:24829278

Gershwin, Lisa-ann; Condie, Scott A; Mansbridge, Jim V; Richardson, Anthony J

2014-07-01

90

First aid for jellyfish envenomation.  

PubMed

To determine a reliable first aid topical remedy for jellyfish stings, we investigated several commonly available preparations to determine their ability to prevent nematocyst rupture from sea nettle (Chrysaora quinquecirrha) and Portuguese man-of-war (Physalia physalis) tentacles. The application of a baking soda slurry was a good inhibitor of nematocyst discharge for the nettle and vinegar was a good inhibitor for the man-of-war. PMID:6135257

Burnett, J W; Rubinstein, H; Calton, G J

1983-07-01

91

Evidence for impacts by jellyfish on North Sea herring recruitment  

Microsoft Academic Search

Jellyfish (Scyphozoa) prey on and consume many of the same food items as do larvae of herring Clupea harengus and could therefore have a detrimental impact on larval survival. A reduc- tion in the spawning stock biomass of herring may release jellyfish from competition for prey with herring and exacerbate any impact by jellyfish on herring survival. Both jellyfish abundance

Christopher P. Lynam; Michael R. Heath; Stephen J. Hay; Andrew S. Brierley

2005-01-01

92

Exceptionally Preserved Jellyfishes from the Middle Cambrian  

Microsoft Academic Search

Cnidarians represent an early diverging animal group and thus insight into their origin and diversification is key to understanding metazoan evolution. Further, cnidarian jellyfish comprise an important component of modern marine planktonic ecosystems. Here we report on exceptionally preserved cnidarian jellyfish fossils from the Middle Cambrian (?505 million years old) Marjum Formation of Utah. These are the first described Cambrian

Paulyn Cartwright; Susan L. Halgedahl; Jonathan R. Hendricks; Richard D. Jarrard; Antonio C. Marques; Allen G. Collins; Bruce S. Lieberman; Stuart Humphries

2007-01-01

93

Jellyfish Modulate Bacterial Dynamic and Community Structure  

PubMed Central

Jellyfish blooms have increased in coastal areas around the world and the outbreaks have become longer and more frequent over the past few decades. The Mediterranean Sea is among the heavily affected regions and the common bloom - forming taxa are scyphozoans Aurelia aurita s.l., Pelagia noctiluca, and Rhizostoma pulmo. Jellyfish have few natural predators, therefore their carcasses at the termination of a bloom represent an organic-rich substrate that supports rapid bacterial growth, and may have a large impact on the surrounding environment. The focus of this study was to explore whether jellyfish substrate have an impact on bacterial community phylotype selection. We conducted in situ jellyfish - enrichment experiment with three different jellyfish species. Bacterial dynamic together with nutrients were monitored to assess decaying jellyfish-bacteria dynamics. Our results show that jellyfish biomass is characterized by protein rich organic matter, which is highly bioavailable to ‘jellyfish - associated’ and ‘free - living’ bacteria, and triggers rapid shifts in bacterial population dynamics and composition. Based on 16S rRNA clone libraries and denaturing gradient gel electrophoresis (DGGE) analysis, we observed a rapid shift in community composition from unculturable Alphaproteobacteria to culturable species of Gammaproteobacteria and Flavobacteria. The results of sequence analyses of bacterial isolates and of total bacterial community determined by culture independent genetic analysis showed the dominance of the Pseudoalteromonadaceae and the Vibrionaceae families. Elevated levels of dissolved proteins, dissolved organic and inorganic nutrient release, bacterial abundance and carbon production as well as ammonium concentrations characterized the degradation process. The biochemical composition of jellyfish species may influence changes in the amount of accumulated dissolved organic and inorganic nutrients. Our results can contribute insights into possible changes in bacterial population dynamics and nutrient pathways following jellyfish blooms which have important implications for ecology of coastal waters. PMID:22745726

Tinta, Tinkara; Kogovšek, Tjaša; Malej, Alenka; Turk, Valentina

2012-01-01

94

Exceptionally Preserved Jellyfishes from the Middle Cambrian  

E-print Network

Cnidarians represent an early diverging animal group and thus insight into their origin and diversification is key to understanding metazoan evolution. Further, cnidarian jellyfish comprise an important component of modern marine planktonic...

Cartwright, Paulyn; Halgedahl, Susan L.; Hendricks, Jonathan R.; Jarrard, Richard D.; Marques, Antonio; Collins, Allen G.; Lieberman, Bruce S.

2007-10-01

95

Exceptionally preserved jellyfishes from the Middle Cambrian.  

PubMed

Cnidarians represent an early diverging animal group and thus insight into their origin and diversification is key to understanding metazoan evolution. Further, cnidarian jellyfish comprise an important component of modern marine planktonic ecosystems. Here we report on exceptionally preserved cnidarian jellyfish fossils from the Middle Cambrian (approximately 505 million years old) Marjum Formation of Utah. These are the first described Cambrian jellyfish fossils to display exquisite preservation of soft part anatomy including detailed features of structures interpreted as trailing tentacles and subumbrellar and exumbrellar surfaces. If the interpretation of these preserved characters is correct, their presence is diagnostic of modern jellyfish taxa. These new discoveries may provide insight into the scope of cnidarian diversity shortly after the Cambrian radiation, and would reinforce the notion that important taxonomic components of the modern planktonic realm were in place by the Cambrian period. PMID:17971881

Cartwright, Paulyn; Halgedahl, Susan L; Hendricks, Jonathan R; Jarrard, Richard D; Marques, Antonio C; Collins, Allen G; Lieberman, Bruce S

2007-01-01

96

Exceptionally Preserved Jellyfishes from the Middle Cambrian  

PubMed Central

Cnidarians represent an early diverging animal group and thus insight into their origin and diversification is key to understanding metazoan evolution. Further, cnidarian jellyfish comprise an important component of modern marine planktonic ecosystems. Here we report on exceptionally preserved cnidarian jellyfish fossils from the Middle Cambrian (?505 million years old) Marjum Formation of Utah. These are the first described Cambrian jellyfish fossils to display exquisite preservation of soft part anatomy including detailed features of structures interpreted as trailing tentacles and subumbrellar and exumbrellar surfaces. If the interpretation of these preserved characters is correct, their presence is diagnostic of modern jellyfish taxa. These new discoveries may provide insight into the scope of cnidarian diversity shortly after the Cambrian radiation, and would reinforce the notion that important taxonomic components of the modern planktonic realm were in place by the Cambrian period. PMID:17971881

Cartwright, Paulyn; Halgedahl, Susan L.; Hendricks, Jonathan R.; Jarrard, Richard D.; Marques, Antonio C.; Collins, Allen G.; Lieberman, Bruce S.

2007-01-01

97

Exceptionally preserved jellyfishes from the Middle Cambrian  

E-print Network

Cnidarians represent an early diverging animal group and thus insight into their origin and diversification is key to understanding metazoan evolution. Further, cnidarian jellyfish comprise an important component of modern marine planktonic ecosystems. Here we report on exceptionally preserved cnidarian jellyfish fossils from the Middle Cambrian (,505 million years old) Marjum Formation of Utah. These are the first described Cambrian jellyfish fossils to display exquisite preservation of soft part anatomy including detailed features of structures interpreted as trailing tentacles and subumbrellar and exumbrellar surfaces. If the interpretation of these preserved characters is correct, their presence is diagnostic of modern jellyfish taxa. These new discoveries may provide insight into the scope of cnidarian diversity shortly after the Cambrian radiation, and would reinforce the notion that important taxonomic components of the modern planktonic realm were in place by the Cambrian period.

Paulyn Cartwright; Susan L. Halgedahl; Jonathan R. Hendricks; Richard D. Jarrard; Antonio C. Marques; Allen G. Collins; Bruce S

2007-01-01

98

Immunostimulatory effects of collagen from jellyfish in vivo  

Microsoft Academic Search

We focused on the biological activity of the collagen extracts obtained from the giant edible jellyfish, Nemopilema nomurai. Jellyfish collagen extracts stimulates the production of immunoglobulins (Igs) and cytokines by human hybridoma cells and\\u000a human peripheral blood lymphocytes. Therefore, we examined the immunoregulatory function of jellyfish collagen extracts in\\u000a mice. Intake of jellyfish collagen extracts facilitated the Ig production activity

Hitoshi Morishige; Takuya Sugahara; Sogo Nishimoto; Ayako Muranaka; Fumi Ohno; Ryusuke Shiraishi; Mikiharu Doi

99

TWO DIMENSIONAL IMMERSED BOUNDARY SIMULATIONS OF SWIMMING JELLYFISH  

E-print Network

TWO DIMENSIONAL IMMERSED BOUNDARY SIMULATIONS OF SWIMMING JELLYFISH by Haowen Fang B.Eng., Nanjing Simulations Of Swim- ming Jellyfish Examining Committee: Dr. Weiran Sun, Assistant Professor Chair Dr. John iii #12;Abstract The swimming behavior of jellyfish, driven by the periodic contraction of body

Stockie, John

100

Jellyfish: A Conceptual Model for the AS Internet Georgos Siganos  

E-print Network

Jellyfish: A Conceptual Model for the AS Internet Topology Georgos Siganos U. C. Riverside siganos importance of a node. We propose the jellyfish as a model for the inter-domain Internet topology. We show- serve that the jellyfish has lasting value: it de- scribes the topology for more than six years. 1

Faloutsos, Michalis

101

Philiadium Gregarum versus Aurelia aurita: on propulsion efficiency in jellyfish  

E-print Network

Philiadium Gregarum versus Aurelia aurita: on propulsion efficiency in jellyfish S. Etienne , A jellyfishes, Philiadium Gregarum and Aurelia aurita. The motion is generated by circular muscles that contract and generate a hydrodynamic propulsive jet. This jet is the principal source of thrust of jellyfishes

Cameron, Chris B.

102

JELLYFISHES AND RELATED ANIMALS by Victor L . Loosanoff  

E-print Network

) ) ) ) JELLYFISHES AND RELATED ANIMALS by Victor L . Loosanoff Biologic al Laboratory Bureau ... .. . . . ............ ...... . INTRODUCTION Page 2 2 3 4 Jellyfishes or, as they are often called, "sea nettles " belong to a very larg e about by the aid of tentacles, some by Anthozoa.......................... . . Control of jellyfish

103

A shift to parasitism in the jellyfish symbiont Symbiodinium microadriaticum  

E-print Network

A shift to parasitism in the jellyfish symbiont Symbiodinium microadriaticum Joel L. Sachs of cooperation between species is found in corals, hydras and jellyfish that form symbioses with algae evolution, should be selected to parasitize their hosts. We altered algal transmission between jellyfish

Sachs, Joel

104

Diving behaviour of jellyfish equipped with electronic tags  

E-print Network

Diving behaviour of jellyfish equipped with electronic tags GRAEME C. HAYS1*, THOMAS K. DOYLE2 online January 27, 2008 Communicating editor: Roger Harris Jellyfish are one of the most abundant compass jellyfish (Chrysaora hysoscella) (n ¼ 15) off the Dingle coast, Ireland, with miniature time

Hays, Graeme

105

Once you click on the Jellyfish link, you are taken to the Home page. Jellyfish does not require a login for searching.  

E-print Network

HOME SEARCHING Once you click on the Jellyfish link, you are taken to the Home page. Jellyfish does clicking once on the TRC report will provide TRC data as shown in window below. To return to Jellyfish main

Chapman, Michael S.

106

Jellyfish Blooms: Causes, Consequences, and Recent Advances  

E-print Network

Abstract To date, a disparate array of concepts and methods have been used to study the growth of jellyfish, with the result that few generalities have emerged which could help, e.g., in predicting growth patterns in unstudied species. It is shown that this situation can be overcome by length-frequency analysis (LFA), applied to jellyfish bell diameter (i.e., ‘‘length’’) frequency data. A selection of LFA methods (ELEFAN, Wetherall plots and lengthconverted catch curves, all implemented in the FiSAT software) is applied here to 34 sets of bell diameter frequency data of jellyfish. This led to the estimates of parameters of the von Bertalanffy growth function (VBGF), which, especially in its seasonal form, was found to fit the available size-frequency data reasonably well. We also obtained numerous estimates of mortality, useful for modeling the life history of jellyfish. Finally, by scaling their asymptotic weight (W?, a parameter of the VBGF) to the weight they would have if they had the same water content as fish, we show that most jellyfish grow at the same rate as

Ó Springer; Science+business Media B. V; J. E. Purcell; M. L. D. Palomares; D. Pauly; D. Pauly

2008-01-01

107

Recurrent jellyfish blooms are a consequence of global oscillations.  

PubMed

A perceived recent increase in global jellyfish abundance has been portrayed as a symptom of degraded oceans. This perception is based primarily on a few case studies and anecdotal evidence, but a formal analysis of global temporal trends in jellyfish populations has been missing. Here, we analyze all available long-term datasets on changes in jellyfish abundance across multiple coastal stations, using linear and logistic mixed models and effect-size analysis to show that there is no robust evidence for a global increase in jellyfish. Although there has been a small linear increase in jellyfish since the 1970s, this trend was unsubstantiated by effect-size analysis that showed no difference in the proportion of increasing vs. decreasing jellyfish populations over all time periods examined. Rather, the strongest nonrandom trend indicated jellyfish populations undergo larger, worldwide oscillations with an approximate 20-y periodicity, including a rising phase during the 1990s that contributed to the perception of a global increase in jellyfish abundance. Sustained monitoring is required over the next decade to elucidate with statistical confidence whether the weak increasing linear trend in jellyfish after 1970 is an actual shift in the baseline or part of an oscillation. Irrespective of the nature of increase, given the potential damage posed by jellyfish blooms to fisheries, tourism, and other human industries, our findings foretell recurrent phases of rise and fall in jellyfish populations that society should be prepared to face. PMID:23277544

Condon, Robert H; Duarte, Carlos M; Pitt, Kylie A; Robinson, Kelly L; Lucas, Cathy H; Sutherland, Kelly R; Mianzan, Hermes W; Bogeberg, Molly; Purcell, Jennifer E; Decker, Mary Beth; Uye, Shin-ichi; Madin, Laurence P; Brodeur, Richard D; Haddock, Steven H D; Malej, Alenka; Parry, Gregory D; Eriksen, Elena; Quiñones, Javier; Acha, Marcelo; Harvey, Michel; Arthur, James M; Graham, William M

2013-01-15

108

Recurrent jellyfish blooms are a consequence of global oscillations  

PubMed Central

A perceived recent increase in global jellyfish abundance has been portrayed as a symptom of degraded oceans. This perception is based primarily on a few case studies and anecdotal evidence, but a formal analysis of global temporal trends in jellyfish populations has been missing. Here, we analyze all available long-term datasets on changes in jellyfish abundance across multiple coastal stations, using linear and logistic mixed models and effect-size analysis to show that there is no robust evidence for a global increase in jellyfish. Although there has been a small linear increase in jellyfish since the 1970s, this trend was unsubstantiated by effect-size analysis that showed no difference in the proportion of increasing vs. decreasing jellyfish populations over all time periods examined. Rather, the strongest nonrandom trend indicated jellyfish populations undergo larger, worldwide oscillations with an approximate 20-y periodicity, including a rising phase during the 1990s that contributed to the perception of a global increase in jellyfish abundance. Sustained monitoring is required over the next decade to elucidate with statistical confidence whether the weak increasing linear trend in jellyfish after 1970 is an actual shift in the baseline or part of an oscillation. Irrespective of the nature of increase, given the potential damage posed by jellyfish blooms to fisheries, tourism, and other human industries, our findings foretell recurrent phases of rise and fall in jellyfish populations that society should be prepared to face. PMID:23277544

Condon, Robert H.; Duarte, Carlos M.; Pitt, Kylie A.; Robinson, Kelly L.; Lucas, Cathy H.; Sutherland, Kelly R.; Mianzan, Hermes W.; Bogeberg, Molly; Purcell, Jennifer E.; Decker, Mary Beth; Uye, Shin-ichi; Madin, Laurence P.; Brodeur, Richard D.; Haddock, Steven H. D.; Malej, Alenka; Parry, Gregory D.; Eriksen, Elena; Quiñones, Javier; Acha, Marcelo; Harvey, Michel; Arthur, James M.; Graham, William M.

2013-01-01

109

Feeding Currents Generated by Upside Down Jellyfish  

E-print Network

We present fluid dynamics videos of the pulsing dynamics and the resulting fluid flow generated by the upside down jellyfish, Cassiopea spp. Medusae of this genus are unusual in that they typically rest upside down on the ocean floor and pulse their bells to generate feeding currents, only swimming when significantly disturbed. The pulsing kinematics and fluid flow around these upside down jellyfish is investigated using a combination of videography, flow visualization, and numerical simulation. Significant mixing occurs around and directly above the oral arms and secondary mouths. Numerical simulations using the immersed boundary method with a porous layer representing the oral arms agree with the experimental results. The simulations also suggest that the presence of porous oral arms induce net horizontal flow towards the bell. Coherent vortex rings are not seen in the wake above the jellyfish, but starting and stopping vortices are observed before breaking up as they pass through the elaborate oral arms (i...

Rodriguez, Terry; Gyoerkoe, Megan; Miller, Laura

2010-01-01

110

Jellyfish Body Plans Provide Allometric Advantages beyond Low Carbon Content  

PubMed Central

Jellyfish form spectacular blooms throughout the world’s oceans. Jellyfish body plans are characterised by high water and low carbon contents which enables them to grow much larger than non-gelatinous animals of equivalent carbon content and to deviate from non-gelatinous pelagic animals when incorporated into allometric relationships. Jellyfish have, however, been argued to conform to allometric relationships when carbon content is used as the metric for comparison. Here we test the hypothesis that differences in allometric relationships for several key functional parameters remain for jellyfish even after their body sizes are scaled to their carbon content. Data on carbon and nitrogen contents, rates of respiration, excretion, growth, longevity and swimming velocity of jellyfish and other pelagic animals were assembled. Allometric relationships between each variable and the equivalent spherical diameters of jellyfish and other pelagic animals were compared before and after sizes of jellyfish were standardised for their carbon content. Before standardisation, the slopes of the allometric relationships for respiration, excretion and growth were the same for jellyfish and other pelagic taxa but the intercepts differed. After standardisation, slopes and intercepts for respiration were similar but excretion rates of jellyfish were 10× slower, and growth rates 2× faster than those of other pelagic animals. Longevity of jellyfish was independent of size. The slope of the allometric relationship of swimming velocity of jellyfish differed from that of other pelagic animals but because they are larger jellyfish operate at Reynolds numbers approximately 10× greater than those of other pelagic animals of comparable carbon content. We conclude that low carbon and high water contents alone do not explain the differences in the intercepts or slopes of the allometric relationships of jellyfish and other pelagic animals and that the evolutionary longevity of jellyfish and their propensity to form blooms is facilitated by their unique body plans. PMID:23967331

Pitt, Kylie A.; Duarte, Carlos M.; Lucas, Cathy H.; Sutherland, Kelly R.; Condon, Robert H.; Mianzan, Hermes; Purcell, Jennifer E.; Robinson, Kelly L.; Uye, Shin-Ichi

2013-01-01

111

Advanced optics in a jellyfish eye  

Microsoft Academic Search

Cubozoans, or box jellyfish, differ from all other cnidarians by an active fish-like behaviour and an elaborate sensory apparatus. Each of the four sides of the animal carries a conspicuous sensory club (the rhopalium), which has evolved into a bizarre cluster of different eyes. Two of the eyes on each rhopalium have long been known to resemble eyes of higher

Dan-E. Nilsson; Lars Gislén; Melissa M. Coates; Charlotta Skogh; Anders Garm

2005-01-01

112

Immunostimulatory effects of collagen from jellyfish in vivo.  

PubMed

We focused on the biological activity of the collagen extracts obtained from the giant edible jellyfish, Nemopilema nomurai. Jellyfish collagen extracts stimulates the production of immunoglobulins (Igs) and cytokines by human hybridoma cells and human peripheral blood lymphocytes. Therefore, we examined the immunoregulatory function of jellyfish collagen extracts in mice. Intake of jellyfish collagen extracts facilitated the Ig production activity of lymphocytes from spleen and Peyer's patch. Furthermore, the levels of Igs in the serum clearly increased after the administration of jellyfish collagen extracts. Intake of bovine collagen from Achilles' tendon also activated lymphocytes activity in mice. The activity of total and antigen-specific Ig production in splenocytes from OVA-challenged mice was also enhanced by collagen intake. However, the total and OVA-specific IgE levels in the serum were not affected by the collagen intake. These results suggested that jellyfish collagen extracts stimulates an immune response in vivo, without inducing allergic complications. PMID:21773823

Morishige, Hitoshi; Sugahara, Takuya; Nishimoto, Sogo; Muranaka, Ayako; Ohno, Fumi; Shiraishi, Ryusuke; Doi, Mikiharu

2011-10-01

113

Marine antivenoms.  

PubMed

There is an enormous diversity and complexity of venoms and poisons in marine animals. Fatalities have occurred from envenoming by sea snakes, jellyfish, venomous fish such as stonefish, cone snails, and blue-ringed octopus. Deaths have also followed ingestion of toxins in shellfish, puffer fish (Fugu), and ciguatoxin-containing fish. However antivenoms are generally only available for envenoming by certain sea snakes, the major Australian box jellyfish (Chironex fleckeri) and stonefish. There have been difficulties in characterizing the toxins of C. fleckeri venom, and there are conflicting animals studies on the efficacy of C. fleckeri antivenom. The vast majority of C. fleckeri stings are not life-threatening, with painful skin welts the major finding. However fatalities that do occur usually do so within 5 to 20 minutes of the sting. This unprecedented rapid onset of cardiotoxicity in clinical envenoming suggests that antivenom may need to be given very early (within minutes) and possibly in large doses if a life is to be saved. Forty years of anecdotal experience supports the beneficial effect of stonefish antivenom in relieving the excruciating pain after stonefish spine penetration. It remains uncertain whether stonefish antivenom is efficacious in stings from spines of other venomous fish, and the recommendation of giving the antivenom intramuscularly needs reassessment. PMID:12807313

Currie, Bart J

2003-01-01

114

Jellyfish collagen scaffolds for cartilage tissue engineering.  

PubMed

Porous scaffolds were engineered from refibrillized collagen of the jellyfish Rhopilema esculentum for potential application in cartilage regeneration. The influence of collagen concentration, salinity and temperature on fibril formation was evaluated by turbidity measurements and quantification of fibrillized collagen. The formation of collagen fibrils with a typical banding pattern was confirmed by atomic force microscopy and transmission electron microscopy analysis. Porous scaffolds from jellyfish collagen, refibrillized under optimized conditions, were fabricated by freeze-drying and subsequent chemical cross-linking. Scaffolds possessed an open porosity of 98.2%. The samples were stable under cyclic compression and displayed an elastic behavior. Cytotoxicity tests with human mesenchymal stem cells (hMSCs) did not reveal any cytotoxic effects of the material. Chondrogenic markers SOX9, collagen II and aggrecan were upregulated in direct cultures of hMSCs upon chondrogenic stimulation. The formation of typical extracellular matrix components was further confirmed by quantification of sulfated glycosaminoglycans. PMID:24184178

Hoyer, Birgit; Bernhardt, Anne; Lode, Anja; Heinemann, Sascha; Sewing, Judith; Klinger, Matthias; Notbohm, Holger; Gelinsky, Michael

2014-02-01

115

Mediterranean Jellyfish Venoms: A Review on Scyphomedusae  

PubMed Central

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

Mariottini, Gian Luigi; Pane, Luigi

2010-01-01

116

Jellyfish Stings and Their Management: A Review  

PubMed Central

Jellyfish (cnidarians) have a worldwide distribution. Despite most being harmless, some species may cause local and also systemic reactions. Treatment of jellyfish envenomation is directed at: alleviating the local effects of venom, preventing further nematocyst discharges and controlling systemic reactions, including shock. In severe cases, the most important step is stabilizing and maintaining vital functions. With some differences between species, there seems to be evidence and consensus on oral/topical analgesics, hot water and ice packs as effective painkillers and on 30 s application of domestic vinegar (4%–6% acetic acid) to prevent further discharge of unfired nematocysts remaining on the skin. Conversely, alcohol, methylated spirits and fresh water should be carefully avoided, since they could massively discharge nematocysts; pressure immobilization bandaging should also be avoided, as laboratory studies show that it stimulates additional venom discharge from nematocysts. Most treatment approaches are presently founded on relatively weak evidence; therefore, further research (especially randomized clinical trials) is strongly recommended. Dissemination of appropriate treatment modalities should be deployed to better inform and educate those at risk. Adequate signage should be placed at beaches to notify tourists of the jellyfish risk. Swimmers in risky areas should wear protective equipment. PMID:23434796

Cegolon, Luca; Heymann, William C.; Lange, John H.; Mastrangelo, Giuseppe

2013-01-01

117

Mediterranean jellyfish venoms: A review on scyphomedusae  

E-print Network

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

Gian Luigi Mariottini; Luigi Pane

118

Artificial jellyfish: evolutionary optimization of swimming  

E-print Network

Jellyfish, also known as "medusae", move by rhythmically contracting and expanding their bell-shaped bodies and are the earliest known animals to achieve locomotion through the muscle power. Development of a generalized dynamical model of medusan swimming is of interest to biologists as well as engineers. In this paper we present a new approach to modeling the swimming behavior of a jellyfish. Due to the axial symmetry of the creature we used a 2D cross-section for the calculation with the surface of the bell represented by two hemi-ellipsoidal curves. A simplified approach based on non-linear deformations of a geometric object is used to model the bell contraction-expansion cycle. We used a particle-gridless hybrid method for the analysis of incompressible flows, with averaging velocities field by the Shepard’s method (partition of unity). To the best of our knowledge this is the first work where the optimal contraction and expansion parameters for the jellyfish movement were found by solving the optimization problem of maximizing the speed while minimizing the energy loss.

V. Lazunin; V. Savchenko

119

Anthropogenic causes of jellyfish blooms and their direct consequences for humans: a review  

Microsoft Academic Search

Although recent articles state that jellyfish populations are increasing, most available evidence shows that jellyfish abundances fluctuate with climatic cycles. Reports of increasing prob- lems with jellyfish, especially in East Asia, are too recent to exclude decadal climate cycles. Jellyfish are infamous for their direct negative effects on human enterprise; specifically, they interfere with tourism by stinging swimmers, fishing by

Jennifer E. Purcell; Shin-ichi Uye; Wen-Tseng Lo

2007-01-01

120

Jellyfish: A fast k-mer counter G. Marcais and C. Kingsford  

E-print Network

Jellyfish: A fast k-mer counter G. Marcais and C. Kingsford February 17, 2012 Version 1.1.4 Abstract Jellyfish is a software to count k-mers in DNA sequences. 1 Synopsis jellyfish count [-oprefix] [-mmerlength] [-tthreads] [-shashsize] [- -both-strands] fasta [fasta . . .] jellyfish merge hash1 hash2

Gruner, Daniel S.

121

A GLIMPSE OF THE SOUTHERN JELLYFISH NEBULA AND ITS MASSIVE YSO E. P. Mercer,1  

E-print Network

A GLIMPSE OF THE SOUTHERN JELLYFISH NEBULA AND ITS MASSIVE YSO E. P. Mercer,1 D. P. Clemens,1 J. M a unique and pro- vocative nebular object we call the ``Southern Jellyfish Nebula.'' The Southern Jellyfish model. Based on its far-IR luminosity of 3:3 Æ 0:9 ; 104 L, the Southern Jellyfish's MYSO has a zero

Clemens, Dan

122

Jellyfish populations in the Mediterranean Sea Lucas BROTz* and Daniel PAULy  

E-print Network

Jellyfish populations in the Mediterranean Sea Lucas BROTz* and Daniel PAULy Sea Around Us Project Sea is home to numerous species of jellyfish, both native and invasive. Some of these jellyfish, which are rarely sampled or studied. In addition, par- ticular species of jellyfish are of high public interest due

Pauly, Daniel

123

A shift to parasitism in the jellyfish symbiont Symbiodinium microadriaticum  

Microsoft Academic Search

One of the outstanding and poorly understood examples of cooperation between species is found in corals, hydras and jellyfish that form symbioses with algae. These mutualistic algae are mostly acquired infectiously from the seawater and, according to models of virulence evolution, should be selected to parasitize their hosts. We altered algal transmission between jellyfish hosts in the laboratory to examine

Joel L. Sachs; Thomas P. Wilcox

2006-01-01

124

Jellyfish blooms in China: Dominant species, causes and consequences  

Microsoft Academic Search

Three jellyfish species, Aurelia aurita, Cyanea nozakii and Nemopilema nomurai, form large blooms in Chinese seas. We report on the distribution and increasing incidence of jellyfish blooms and their consequences in Chinese coastal seas and analyze their relationship to anthropogenically derived changes to the environment in order to determine the possible causes. A. aurita, C. nozakii and N. nomurai form

Zhijun Dong; Dongyan Liu; John K. Keesing

2010-01-01

125

Scyphozoan jellyfish venom metalloproteinases and their role in the cytotoxicity  

Microsoft Academic Search

The present study, for the first time, comparatively investigated the enzymatic activities (proteases and hyaluronidases) in the venoms of four Scyphozoan jellyfish species, including Nemopilema nomurai, Rhopilema esculenta, Cyanea nozakii, and Aurelia aurita. For this, various zymographic analyses were performed using assay specific substrates. Interestingly, all the four jellyfish venoms showed gelatinolytic, caseinolytic, and fibrinolytic activities, each of which contains

Hyunkyoung Lee; Eun-sun Jung; Changkeun Kang; Won Duk Yoon; Jong-Shu Kim; Euikyung Kim

2011-01-01

126

Occurrence of organo-arsenicals in jellyfishes and their mucus.  

PubMed

Water-soluble arsenic compound fractions were extracted from seven species of jellyfishes and subjected to analysis by high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS) for arsenicals. A low content of arsenic was found to be the characteristic of jellyfish. Arsenobetaine (AB) was the major arsenic compound without exception in the tissues of the jellyfish species and mucus-blobs collected from some of them. Although the arsenic content in Beroe cucumis, which preys on Bolinopsis mikado, was more than 13 times that in B. mikado, the chromatograms of these two species were similar in the distribution pattern of arsenicals. The nine species of jellyfishes including two species treated in the previous paper can be classified into arsenocholine (AC)-rich and AC-poor species. Jellyfishes belonging to Semaostamae were classified as AC-rich species. PMID:11482664

Hanaoka, K; Ohno, H; Wada, N; Ueno, S; Goessler, W; Kuehnelt, D; Schlagenhaufen, C; Kaise, T; Irgolic, K J

2001-08-01

127

Jellyfish (Stomolophus meleagris) Tentacles Proteins and their Proteolysis Endogenous  

E-print Network

Abstract—The goal of the project was to study the protein from jellyfish tentacles found in the sea, by 1D gel electrophoresis, and the study of proteolysis endogenous using commercial substrates such as hemoglobin and casein. might be useful in the biotechnology industry, such as enzymes. The purpose of this study was to obtain the electrophoretic profile of proteins found in jellyfish tentacles and the study of proteolysis in a wide range of pH. Keywords—Jellyfish, proteases, proteolysis. I.

Legarreta I. A

128

Evolution and functional diversity of jellyfish opsins.  

PubMed

Cnidaria are the most basal animal phylum possessing complex eyes [1]. Their eyes predominantly use ciliary photoreceptor cells (c-PRCs) like vertebrates, whereas insect eyes use rhabdomeric photoreceptor cells (r-PRCs) [1-4]. These two cell types show not only different cytoarchitectures but distinct phototransduction cascades, which are triggered by the respective types of opsins (e.g., [5]), ciliary opsins (c-opsins) and rhabdomeric opsins (r-opsins) [6]. Recent reports suggested that the c- and r-PRCs and their respective opsins diverged at least before the deuterostome-protostome split [7-9]. To study the earlier evolution of animal PRCs and opsins, we investigated two hydrozoan jellyfishes. We report here the first-characterized cnidarian opsins. Molecular phylogeny revealed that the cloned 20 jellyfish opsins, together with all the opsins from a hydra and some from a sea anemone, are more closely related to the c-opsins than to any other major opsin subfamily, indicating that the divergence of c- and r-opsins antedates the Cnidaria-Bilateria split. Possible scenarios of animal PRC evolution are discussed. Furthermore, Cladonema opsins show several distinct tissue- and stage-specific expression patterns. The expression of specific opsins in the eyes suggests a role in vision, whereas that in the gonads suggests a role in light-controlled release of gametes. PMID:18160295

Suga, Hiroshi; Schmid, Volker; Gehring, Walter J

2008-01-01

129

PHYLOGENETIC SYSTEMATICS, TAXONOMY, AND BIOGEOGRAPHY OF JELLYFISH (CNIDARIA: MEDUSOZOA)  

E-print Network

The coastal shelf inhabiting box jellyfish (Cubozoa) represent the smallest class within Cnidaria with some 50 described species. A robust phylogenetic framework had been missing for Cubozoa. Herein, a molecular phylogeny for Cubozoa is presented...

Bentlage, Bastian

2012-08-31

130

Jellyfish blooms in China: Dominant species, causes and consequences.  

PubMed

Three jellyfish species, Aurelia aurita, Cyanea nozakii and Nemopilema nomurai, form large blooms in Chinese seas. We report on the distribution and increasing incidence of jellyfish blooms and their consequences in Chinese coastal seas and analyze their relationship to anthropogenically derived changes to the environment in order to determine the possible causes. A. aurita, C. nozakii and N. nomurai form blooms in the temperate Chinese seas including the northern East China Sea, Yellow Sea and Bohai Sea. N. nomurai forms offshore blooms while the other two species bloom mainly in inshore areas. Eutrophication, overfishing, habitat modification for aquaculture and climate change are all possible contributory factors facilitating plausible mechanisms for the proliferation of jellyfish blooms. In the absence of improvement in coastal marine ecosystem health, jellyfish blooms could be sustained and may even spread from the locations in which they now occur. PMID:20553695

Dong, Zhijun; Liu, Dongyan; Keesing, John K

2010-07-01

131

Isolation and characterization of collagen from rhizostomous jellyfish ( Rhopilema asamushi)  

Microsoft Academic Search

As a part of the study into the potential development of unused and under-used resources, collagen was isolated from the mesogloea of the rhizostomous jellyfish, Rhopilema asamushi, by limited pepsin digestion and characterized. The yield of this collagen was high (35.2% on a dry weight basis). The primary structure was very similar to that of pepsin-solubilized collagen from edible jellyfish

Takeshi Nagai; Wanchai Worawattanamateekul; Nobutaka Suzuki; Takashi Nakamura; Tatsumi Ito; Kazuhiro Fujiki; Miki Nakao; Tomoki Yano

2000-01-01

132

Scyphozoan jellyfish venom metalloproteinases and their role in the cytotoxicity.  

PubMed

The present study, for the first time, comparatively investigated the enzymatic activities (proteases and hyaluronidases) in the venoms of four Scyphozoan jellyfish species, including Nemopilema nomurai, Rhopilema esculenta, Cyanea nozakii, and Aurelia aurita. For this, various zymographic analyses were performed using assay specific substrates. Interestingly, all the four jellyfish venoms showed gelatinolytic, caseinolytic, and fibrinolytic activities, each of which contains a multitude of enzyme components with molecular weights between 17 and 130 kDa. These four jellyfish venoms demonstrated a huge variation in their proteolytic activities in quantitative and qualitative manner depending on the species. Most of these enzymatic activities were disappeared by the treatment of 1,10-phenanthroline, suggesting they might be belonged to metalloproteinases. Toxicological significance of these venom proteases was examined by comparing their proteolytic activity and the cytotoxicity in NIH 3T3 cells. The relative cytotoxic potency was C. nozakii > N. nomurai > A. aurita > R. esculenta. The cytotoxicity of jellyfish venom shows a positive correlation with its overall proteolytic activity. The metalloproteinases appear to play an important role in the induction of jellyfish venom toxicities. In conclusion, the present report proposes a novel finding of Scyphozoan jellyfish venom metalloproteinases and their potential role in the cytotoxicity. PMID:21718715

Lee, Hyunkyoung; Jung, Eun-sun; Kang, Changkeun; Yoon, Won Duk; Kim, Jong-Shu; Kim, Euikyung

2011-09-01

133

Subducting Slabs: Jellyfishes in the Earth's Mantle  

NASA Astrophysics Data System (ADS)

The constantly improving resolution of geophysical data, seismic tomography and seismicity in particular, shows that the lithosphere does not subduct as a slab of uniform thickness but is rather thinned in the upper mantle and thickened around the transition zone between the upper and lower mantle. This observation has traditionally been interpreted as evidence for the buckling and piling of slabs at the boundary between the upper and lower mantle, where a strong contrast in viscosity may exist and cause resistance to the penetration of slabs into the lower mantle. The distribution and character of seismicity reveal, however, that slabs undergo vertical extension in the upper mantle and compression near the transition zone. In this paper, we demonstrate that during the subduction process, the shape of low viscosity slabs (1 to 100 times more viscous than the surrounding mantle) evolves toward an inverted plume shape that we coin jellyfish. Results of a 3D numerical model show that the leading tip of slabs deform toward a rounded head skirted by lateral tentacles that emerge from the sides of the jellyfish head. The head is linked to the body of the subducting slab by a thin tail. A complete parametric study reveals that subducting slabs may achieve a variety of shapes, in good agreement with the diversity of natural slab shapes evidenced by seismic tomography. Our work also suggests that the slab to mantle viscosity ratio in the Earth is most likely to be lower than 100. However, the sensitivity of slab shapes to upper and lower mantle viscosities and densities, which remain poorly constrained by independent evidence, precludes any systematic deciphering of the observations.

Loiselet, C.; Braun, J.; Husson, L.; Le Carlier de Veslud, C.; Thieulot, C.; Yamato, P.; Grujic, D.

2010-12-01

134

Subducting slabs: Jellyfishes in the Earth's mantle  

NASA Astrophysics Data System (ADS)

The constantly improving resolution of geophysical data, seismic tomography and seismicity in particular, shows that the lithosphere does not subduct as a slab of uniform thickness but is rather thinned in the upper mantle and thickened around the transition zone between the upper and lower mantle. This observation has traditionally been interpreted as evidence for the buckling and piling of slabs at the boundary between the upper and lower mantle, where a strong contrast in viscosity may exist and cause resistance to the penetration of slabs into the lower mantle. The distribution and character of seismicity reveal, however, that slabs undergo vertical extension in the upper mantle and compression near the transition zone. In this paper, we demonstrate that during the subduction process, the shape of low viscosity slabs (1 to 100 times more viscous than the surrounding mantle) evolves toward an inverted plume shape that we coin jellyfish. Results of a 3D numerical model show that the leading tip of slabs deform toward a rounded head skirted by lateral tentacles that emerge from the sides of the jellyfish head. The head is linked to the body of the subducting slab by a thin tail. A complete parametric study reveals that subducting slabs may achieve a variety of shapes, in good agreement with the diversity of natural slab shapes evidenced by seismic tomography. Our work also suggests that the slab to mantle viscosity ratio in the Earth is most likely to be lower than 100. However, the sensitivity of slab shapes to upper and lower mantle viscosities and densities, which remain poorly constrained by independent evidence, precludes any systematic deciphering of the observations.

Loiselet, Christelle; Braun, Jean; Husson, Laurent; Le Carlier de Veslud, Christian; Thieulot, Cedric; Yamato, Philippe; Grujic, Djordje

2010-08-01

135

Jellyfish: Networking Data Centers Randomly Ankit Singla, Chi-Yao Hong, Lucian Popa , P. Brighten Godfrey  

E-print Network

Jellyfish: Networking Data Centers Randomly Ankit Singla, Chi-Yao Hong, Lucian Popa , P. Brighten designs have rigid struc- ture that interferes with incremental expansion. We present Jellyfish, a high expansion. Somewhat sur- prisingly, Jellyfish is more cost-efficient than a fat-tree, supporting as many

Ratnasamy, Sylvia

136

First Complete Mitochondrial Genome Sequence from a Box Jellyfish Reveals a Highly Fragmented Linear  

E-print Network

First Complete Mitochondrial Genome Sequence from a Box Jellyfish Reveals a Highly Fragmented medusozoan cnidarians (jellyfish and hydroids), which are linear and sometimes fragmented. Most medusozoans that box jellyfish (cubozoans) have mtDNAs that consist of many linear chromosomes. Here, we present

Keeling, Patrick

137

High activity and Le vy searches: jellyfish can search the water column like fish  

E-print Network

High activity and Le´ vy searches: jellyfish can search the water column like fish Graeme C. Hays1 and a proliferation of jellyfish. Active movements and prey search might be thought to provide a competitive advantage for fish, but here we use data-loggers to show that the frequently occurring coastal jellyfish (Rhizostoma

Hays, Graeme

138

Abstract Jellyfish (medusae) are sometimes the most noticeable and abundant members of coastal  

E-print Network

Abstract Jellyfish (medusae) are sometimes the most noticeable and abundant members of coastal the spatial (and temporal) patterns for five jellyfish species (Phylum Cnidaria, Orders Rhizostomeae-counts of jellyfish from ships of opportu- nity, and (2) regular shoreline surveys for stranding events over three

Hays, Graeme

139

Finding a dense-core in Jellyfish graphs Mira Gonen *, Dana Ron 1  

E-print Network

Finding a dense-core in Jellyfish graphs Mira Gonen *, Dana Ron 1 , Udi Weinsberg, Avishai Wool topology was suggested by Tauro et al. [35]. This work seems to have coined the ``Jellyfish" term. The authors argued that the Internet topology resembles a Jellyfish where the 1389-1286/$ - see front matter Ó

Wool, Avishai

140

A New Routing Scheme for Jellyfish and its Performance with HPC Workloads  

E-print Network

A New Routing Scheme for Jellyfish and its Performance with HPC Workloads Xin Yuan Dept Alamos, New Mexico mlang@lanl.gov ABSTRACT The jellyfish topology where switches are connected using with a similar cost. In this work, we propose a new routing scheme for jellyfish that out-performs existing

Pakin, Scott

141

Tracking the Motion of Box Jellyfish Tobias Kjellberg Magnus Oskarsson Tobias Palmr Kalle strm  

E-print Network

Tracking the Motion of Box Jellyfish Tobias Kjellberg Magnus Oskarsson Tobias Palmér Kalle Åström with different box jellyfishes, light conditions and artefacts, forcing the solution to be more of a generic-realtime. 1.4 The jellyfish - Tripedalia cystophora Tripedalia cystophora is a roughly 1 cm sized box

Lunds Universitet

142

Fact Sheet No. 96-5, March 1996 Freshwater jellyfish, Craspedacusta sowerbyii,  

E-print Network

Kelly Addy Fact Sheet No. 96-5, March 1996 URI Freshwater jellyfish, Craspedacusta sowerbyii, were of jellyfish was ever recorded in RI natural history, Waterman Lake in Glocester/Smithfield in 1990. In 1995 Sprague Reservoir in Smithfield observed thousands of these jellyfish in their respective lakes. After

Rhode Island, University of

143

Have jellyfish in the Irish Sea benefited from climate change and overfishing?  

E-print Network

Have jellyfish in the Irish Sea benefited from climate change and overfishing? C . P. LY N A M *, M instability and may benefit nonexploited organisms such as jellyfish. In the Irish Sea, an increase in jellyfish abundance was evident (r2 5 0.29, P 5 0.03) in a 16-year time-series (1994­2009) collected during

Hays, Graeme

144

Passive energy recapture in jellyfish contributes to propulsive advantage over other metazoans  

E-print Network

Passive energy recapture in jellyfish contributes to propulsive advantage over other metazoans Brad predatory mode is counterintuitive because jellyfish are described as inefficient swimmers that must rely on direct contact with prey to feed. We show that jellyfish exhibit a unique mech- anism of passive energy

Dabiri, John O.

145

Ecosystem Engineers in the Pelagic Realm: Alteration of Habitat by Species Ranging from Microbes to Jellyfish  

E-print Network

Microbes to Jellyfish Denise L. Breitburg,1, * Byron C. Crump, John O. Dabiri and Charles L. Gallegos structure to the environment, but organisms ranging from microbes to jellyfish and finfish that reside the classical category of ecosystem engineer. In addition, planktonic species, such as jellyfish, may indirectly

Dabiri, John O.

146

The energy density of jellyfish: Estimates from bomb-calorimetry and proximate-composition  

E-print Network

The energy density of jellyfish: Estimates from bomb-calorimetry and proximate-composition Thomas K scyphozoan jellyfish (Cyanea capillata, Rhizostoma octopus and Chrysaora hysoscella). First, bomb of these low energy densities for species feeding on jellyfish are discussed. © 2007 Elsevier B.V. All rights

Hays, Graeme

147

Target organ identification of jellyfish envenomation using systemic and integrative analyses in anesthetized dogs  

Microsoft Academic Search

Proper treatment of jellyfish envenomed patients can be successfully achieved only from an understanding of the overall functional changes and alterations in physiological parameters under its envenomation. The majority of previous investigations on jellyfish venoms have covered only a couple of parameters at a time. Unlike most other fragmentary jellyfish studies, we employed an integrative toxicological approach, including hemodynamics, clinical

Changkeun Kang; Young Ki Kim; Hyunkyoung Lee; Mijin Cha; Eun-Tae Sohn; Eun-Sun Jung; Chiyoun Song; Minkyung Kim; Hee Chun Lee; Jong-Shu Kim; Jin-Yong Hwang; Won Duk Yoon; Euikyung Kim

2011-01-01

148

Identification of genetically and oceanographically distinct blooms of jellyfish  

PubMed Central

Reports of nuisance jellyfish blooms have increased worldwide during the last half-century, but the possible causes remain unclear. A persistent difficulty lies in identifying whether blooms occur owing to local or regional processes. This issue can be resolved, in part, by establishing the geographical scales of connectivity among locations, which may be addressed using genetic analyses and oceanographic modelling. We used landscape genetics and Lagrangian modelling of oceanographic dispersal to explore patterns of connectivity in the scyphozoan jellyfish Rhizostoma octopus, which occurs en masse at locations in the Irish Sea and northeastern Atlantic. We found significant genetic structure distinguishing three populations, with both consistencies and inconsistencies with prevailing physical oceanographic patterns. Our analyses identify locations where blooms occur in apparently geographically isolated populations, locations where blooms may be the source or result of migrants, and a location where blooms do not occur consistently and jellyfish are mostly immigrant. Our interdisciplinary approach thus provides a means to ascertain the geographical origins of jellyfish in outbreaks, which may have wide utility as increased international efforts investigate jellyfish blooms. PMID:23287405

Lee, Patricia L. M.; Dawson, Michael N; Neill, Simon P.; Robins, Peter E.; Houghton, Jonathan D. R.; Doyle, Thomas K.; Hays, Graeme C.

2013-01-01

149

Cytoskeletal “jellyfish” structure of Mycoplasma mobile  

PubMed Central

Mycoplasma mobile, a parasitic bacterium lacking a peptidoglycan layer, glides on solid surfaces in the direction of a membrane protrusion at a cell pole by a unique mechanism. Recently, we proposed a working model in which cells are propelled by leg proteins clustering at the protrusion's base. The legs repeatedly catch and release sialic acids on the solid surface, a motion that is driven by the force generated by ATP hydrolysis. Here, to clarify the subcellular structure supporting the gliding force and the cell shape, we stripped the membrane by Triton X-100 and identified a unique structure, designated the “jellyfish” structure. In this structure, an oval solid “bell” ?235 wide and 155 nm long is filled with a 12-nm hexagonal lattice and connected to this structure are dozens of flexible “tentacles” that are covered with particles of 20-nm diameter at intervals of ?30 nm. The particles appear to have 180° rotational symmetry and a dimple at the center. The relation of this structure to the gliding mechanism was suggested by its cellular localization and by analyses of mutants lacking proteins essential for gliding. We identified 10 proteins as the components by mass spectrometry and found that these do not show sequence similarities with other proteins of bacterial cytoskeletons or the gliding proteins previously identified. Immunofluorescence and immunoelectron microscopy revealed that two components are localized at the bell and another that has the structure similar to the F1-ATPase ? subunit is localized at the tentacles. PMID:18042728

Nakane, Daisuke; Miyata, Makoto

2007-01-01

150

Medical aspects of jellyfish envenomation: pathogenesis, case reporting and therapy  

Microsoft Academic Search

With larger human population numbers and their need for recreation, contact between humans and jellyfish is increasing. The pathogenesis of cnidarian stings is discussed here and some of the factors influencing the variability in adverse reactions they produce are mentioned. The pharmakinetics of venom delivery determines the organ site of damage and the extent of abnormality. Since venoms can injure

Joseph W. Burnett

2001-01-01

151

Protection of human skin against jellyfish ( Cyanea capillata ) stings  

Microsoft Academic Search

In tropical and subtropical regions of the world, jellyfish stings cause fatalities by means of venom injecting nematocysts. For nematocyst discharge an adequate combination of chemical and mechanical stimulation is required. In order to test whether skin care products can protect against nematocyst discharge, we tested two sunscreens and one lotion applied to pieces of live human skin and exposed

Thomas Heeger; Heino Möller; Ulrich Mrowietz

1992-01-01

152

Current-driven Flow across a Stationary Jellyfish  

E-print Network

We present several dye visualization and numerical simulation fluid dynamics videos of a sessile jellyfish subjected to channel flow. The low resolution video and the high resolution video display the vortex patterns in different channel flows. This description accompanies the video submission V038 to the 2011 APS DFD Gallery of Fluid Motion.

Hamlet, Christina; Fan, Roger; Dollinger, Makani; Harenber, Steve

2011-01-01

153

Jellyfish Party: Blowing Soap Bubbles in Mixed Reality Space  

Microsoft Academic Search

This paper describes a mixed reality installation named Jellyfish Party, for enjoying playing with soap bubbles. A special feature of this installation is the use of a spirometer sensor to measure the amount and speed of expelled air used to blow virtual soap bubbles.

Yasuhiro Okuno; Hiroyuki Kakuta; Tomohiko Takayama; Kazuhiro Asai

2003-01-01

154

Evolution of striated muscle: Jellyfish and the origin of triploblasty  

Microsoft Academic Search

The larval and polyp stages of extant Cnidaria are bi-layered with an absence of mesoderm and its differentiation products. This anatomy originally prompted the diploblast classification of the cnidarian phylum. The medusa stage, or jellyfish, however, has a more complex anatomy characterized by a swimming bell with a well-developed striated muscle layer. Based on developmental histology of the hydrozoan medusa

Katja Seipel; Volker Schmid

2005-01-01

155

The cellular eye lens and crystallins of cubomedusan jellyfish  

Microsoft Academic Search

The ultrastructure and major soluble proteins of the transparent eye lens of two cubomedusan jellyfish,Tripedalia cystophora andCarybdea marsupialis, have been examined. Each species has two complex eyes (one large and one small) on four sensory structures called rhopalia. The lenses consist of closely spaced cells with few organelles. The lens is situated next to the retina, with only an acellular

Joram Piatigorsky; Joseph Horwitz; Toichiro Kuwabara; Charles E. Cutress

1989-01-01

156

Skin and Systemic Manifestations of Jellyfish Stings in Iraqi Fishermen  

PubMed Central

Background: Jellyfish stings are common worldwide with an estimated 150 million cases annually, and their stings cause a wide range of clinical manifestations from skin inflammation to cardiovascular and respiratory collapse. No studies on jellyfish stings have been carried out in Basra, Iraq. Objectives: To describe the immediate and delayed skin reactions to White Jellyfish (Rhizostoma sp.) stings and the types of local treatment used by fishermen. Methods and Materials: 150 fishermen were enrolled at three Marine stations in Basra, Iraq. Demographic data, types of skin reactions, systemic manifestations and kinds of treatments were collected. Results: Overall, 79% of fishermen in all three Marine stations gave a history of having been stung. The common sites of sings were the hands and arms followed by the legs. Most fishermen claimed that stings led to skin reactions within 5 minutes. The presenting complaints were itching, burning sensation, and erythematic wheals. A few days after the sting, new groups of painless and itchy erythematous monomorphic papular rashes developed at the site of the sting in 62% of cases as a delayed type of skin reaction that resolved spontaneously. The local remedies commonly used by the fishermen were seawater, tap water and ice. A few fishermen considered stings as insignificant and did not think there was a need to seek medical help. Conclusions: We conclude that jellyfish causes many stings among fishermen in the Basra region. Their stings lead to immediate and delayed skin reactions. Self-treatment by topical remedies is common. PMID:21483513

Al-Rubiay, KK; Al-Musaoi, HA; Alrubaiy, L; Al-Freje, MG

2009-01-01

157

Jellyfish Party: Blowing soap bubbles in mixed reality space  

E-print Network

This paper describes a Mixed Reality installation named Jellyfish Party, for enjoying playing with soap bubbles. A special feature of this installation is the use of a spirometer sensor to measure the amount and speed of expelled air used to blow virtual soap bubbles.

Yasuhiro Okuno; Hiroyuki Kakuta; Tomohiko Takayama; Canon Inc

2003-01-01

158

Cubozoan Venom-Induced Cardiovascular Collapse Is Caused by Hyperkalemia and Prevented by Zinc Gluconate in Mice  

PubMed Central

Chironex fleckeri (Australian box jellyfish) stings can cause acute cardiovascular collapse and death. We developed methods to recover venom with high specific activity, and evaluated the effects of both total venom and constituent porins at doses equivalent to lethal envenomation. Marked potassium release occurred within 5 min and hemolysis within 20 min in human red blood cells (RBC) exposed to venom or purified venom porin. Electron microscopy revealed abundant ?12-nm transmembrane pores in RBC exposed to purified venom porins. C57BL/6 mice injected with venom showed rapid decline in ejection fraction with progression to electromechanical dissociation and electrocardiographic findings consistent with acute hyperkalemia. Recognizing that porin assembly can be inhibited by zinc, we found that zinc gluconate inhibited potassium efflux from RBC exposed to total venom or purified porin, and prolonged survival time in mice following venom injection. These findings suggest that hyperkalemia is the critical event following Chironex fleckeri envenomation and that rapid administration of zinc could be life saving in human sting victims. PMID:23251508

Yanagihara, Angel A.; Shohet, Ralph V.

2012-01-01

159

Cubozoan venom-induced cardiovascular collapse is caused by hyperkalemia and prevented by zinc gluconate in mice.  

PubMed

Chironex fleckeri (Australian box jellyfish) stings can cause acute cardiovascular collapse and death. We developed methods to recover venom with high specific activity, and evaluated the effects of both total venom and constituent porins at doses equivalent to lethal envenomation. Marked potassium release occurred within 5 min and hemolysis within 20 min in human red blood cells (RBC) exposed to venom or purified venom porin. Electron microscopy revealed abundant ~12-nm transmembrane pores in RBC exposed to purified venom porins. C57BL/6 mice injected with venom showed rapid decline in ejection fraction with progression to electromechanical dissociation and electrocardiographic findings consistent with acute hyperkalemia. Recognizing that porin assembly can be inhibited by zinc, we found that zinc gluconate inhibited potassium efflux from RBC exposed to total venom or purified porin, and prolonged survival time in mice following venom injection. These findings suggest that hyperkalemia is the critical event following Chironex fleckeri envenomation and that rapid administration of zinc could be life saving in human sting victims. PMID:23251508

Yanagihara, Angel A; Shohet, Ralph V

2012-01-01

160

Cold packs: effective topical analgesia in the treatment of painful stings by Physalia and other jellyfish.  

PubMed

A study has shown that, when applied to Physalia ("bluebottle") jellyfish stings, cold packs are effective as topical analgesia in the relief of mild-to-moderate skin pain. The application of ice also has been shown to be effective for topical analgesia in a number of other jellyfish stings, including by Cyanea ("hair jellyfish"), Tamoya sp. ("Moreton Bay stinger" or "fire jelly") and Carybdea rastoni ("jimble") as well as by Physalia. In the current state of knowledge, cold packs or ice are recommended as the first-aid treatment for jellyfish stings with local skin pain. PMID:2574408

Exton, D R; Fenner, P J; Williamson, J A

161

A tissue-engineered jellyfish with biomimetic propulsion  

E-print Network

hierarchical design over several orders of space and time. Recent advances in the mechanistic understanding of biosynthetic compound materials 1–3, computer-aided design approaches in molecular synthetic biology 4,5 and traditional soft robotics 6,7, and increasing aptitude in generating structural and chemical microenvironments that promote cellular self-organization 8–10 have enhanced the ability to recapitulate such hierarchical architecture in engineered biological systems. Here we combined these capabilities in a systematic design strategy to reverse engineer a muscular pump. We report the construction of a freely swimming jellyfish from chemically dissociated rat tissue and silicone polymer as a proof of concept. The constructs, termed ‘medusoids’, were designed with computer simulations and experiments to match key determinants of jellyfish propulsion and

Janna C Nawroth; Hyungsuk Lee; Adam W Feinberg; Megan L Mccain; Anna Grosberg; John O Dabiri; Kevin Kit Parker

2012-01-01

162

Biomass of Scyphozoan Jellyfish, and Its Spatial Association with 0-Group Fish in the Barents Sea  

PubMed Central

An 0-group fish survey is conducted annually in the Barents Sea in order to estimate fish population abundance. Data on jellyfish by-catch have been recorded since 1980, although this dataset has never been analysed. In recent years, however, the ecological importance of jellyfish medusae has become widely recognized. In this paper the biomass of jellyfish (medusae) in 0–60 m depths is calculated for the period 1980–2010. During this period the climate changed from cold to warm, and changes in zooplankton and fish distribution and abundance were observed. This paper discusses the less well known ecosystem component; jellyfish medusae within the Phylum Cnidaria, and their spatial and temporal variation. The long term average was ca. 9×108 kg, with some years showing biomasses in excess of 5×109 kg. The biomasses were low during 1980s, increased during 1990s, and were highest in early 2000s with a subsequent decline. The bulk of the jellyfish were observed in the central parts of the Barents Sea, which is a core area for most 0-group fishes. Jellyfish were associated with haddock in the western area, with haddock and herring in the central and coastal area, and with capelin in the northern area of the Barents Sea. The jellyfish were present in the temperature interval 1°Cjellyfish occurring between 4.0–7.0°C. It seems that the ongoing warming trend may be favourable for Barents Sea jellyfish medusae; however their biomass has showed a recent moderate decline during years with record high temperatures in the Barents Sea. Jellyfish are undoubtedly an important component of the Barents Sea ecosystem, and the data presented here represent the best summary of jellyfish biomass and distribution yet published for the region. PMID:22457732

Eriksen, Elena; Prozorkevich, Dmitry; Trofimov, Aleksandr; Howell, Daniel

2012-01-01

163

Biomass of scyphozoan jellyfish, and its spatial association with 0-group fish in the Barents Sea.  

PubMed

An 0-group fish survey is conducted annually in the Barents Sea in order to estimate fish population abundance. Data on jellyfish by-catch have been recorded since 1980, although this dataset has never been analysed. In recent years, however, the ecological importance of jellyfish medusae has become widely recognized. In this paper the biomass of jellyfish (medusae) in 0-60 m depths is calculated for the period 1980-2010. During this period the climate changed from cold to warm, and changes in zooplankton and fish distribution and abundance were observed. This paper discusses the less well known ecosystem component; jellyfish medusae within the Phylum Cnidaria, and their spatial and temporal variation. The long term average was ca. 9×10? kg, with some years showing biomasses in excess of 5×10? kg. The biomasses were low during 1980s, increased during 1990s, and were highest in early 2000s with a subsequent decline. The bulk of the jellyfish were observed in the central parts of the Barents Sea, which is a core area for most 0-group fishes. Jellyfish were associated with haddock in the western area, with haddock and herring in the central and coastal area, and with capelin in the northern area of the Barents Sea. The jellyfish were present in the temperature interval 1°Cjellyfish occurring between 4.0-7.0°C. It seems that the ongoing warming trend may be favourable for Barents Sea jellyfish medusae; however their biomass has showed a recent moderate decline during years with record high temperatures in the Barents Sea. Jellyfish are undoubtedly an important component of the Barents Sea ecosystem, and the data presented here represent the best summary of jellyfish biomass and distribution yet published for the region. PMID:22457732

Eriksen, Elena; Prozorkevich, Dmitry; Trofimov, Aleksandr; Howell, Daniel

2012-01-01

164

Jellyfish swarms, tourists, and the Christ-child  

Microsoft Academic Search

One of the most remarkable sights in the Western Pacific is a perennial swarm of 1.5 million golden medusae (Mastigias sp.) crowded into a land-locked marine lake in Palau, Micronesia. This 'Jellyfish Lake' became a popular off-gassing stopover for SCUBA divers and a destination in its own right for non-diving tourists in the mid-1980s. Since then, tourism in Palau has

Mike N Dawson; Laura E. Martin; Lolita K. Penland

2001-01-01

165

Antibacterial polyketides from the jellyfish-derived fungus Paecilomyces variotii.  

PubMed

Four new polyketides (1-4) were isolated from the fungus Paecilomyces variotii, which was derived from the jellyfish Nemopilema nomurai. The planar structures and relative configurations of these polyketides were elucidated on the basis of spectroscopic analyses, including 2D NMR experiments. The compounds showed inhibitory activity against pathogenic bacteria including methicillin-resistant Staphylococcus aureus 3089 and multi-drug-resistant Vibrio parahemolyticus 7001 with MIC values in the range 5-40 ?g/mL. PMID:21744790

Liu, Juan; Li, Famei; Kim, Eun La; Li, Jian Lin; Hong, Jongki; Bae, Kyung Sook; Chung, Hae Young; Kim, Hyung Sik; Jung, Jee H

2011-08-26

166

Jellyfish monitoring on coastlines using remote piloted aircraft  

NASA Astrophysics Data System (ADS)

In the last 10 years the number of jellyfish shoals that reach the swimming area of the Mediterranean Sea are increasing constantly. The term "Jellyfish" refers to animals from different taxonomic groups but the Scyphomedusae are within the most significant one. Four species of Scyphomedusae are the most conspicuous ones inhabiting the studied area, the Barcelona metropolitan area. Jellyfish are usually found at the surface waters, forming big swarms. This feature makes possible to detect them remotely, using a visual camera and image processing algorithms. In this paper we present the characteristics of a remote piloted aircraft capable to perform monitoring flights during the whole summer season. The requirements of the aircraft are to be easy to operate, to be able to flight at low altitude (100 m) following the buoy line (200 m from the beach line) and to be save for other users of the seaside. The remote piloted aircraft will carry a vision system and a processing board able to obtain useful information on real-time.

Barrado, C.; Fuentes, J. A.; Salamí, E.; Royo, P.; Olariaga, A. D.; López, J.; Fuentes, V. L.; Gili, J. M.; Pastor, E.

2014-03-01

167

Hemolytic venoms from marine cnidarian jellyfish – an overview  

PubMed Central

Cnidarian jellyfish are viewed as an emergent problem in several coastal zones throughout the world. Recurrent outbreaks pose a serious threat to tourists and bathers, as well as to sea-workers, involving health and economical aspects. As a rule, cnidarian stinging as a consequence of nematocyst firing induces merely local symptoms but cardiovascular or neurological complications can also occur. Hemolysis is a frequent effect of cnidarian stinging; this dangerous condition is known to be caused by several venoms and can sometimes be lethal. At present, the bulk of data concerning hemolytic cnidarian venoms comes from the study of benthic species, such as sea anemones and soft corals, but hemolytic factors were found in venoms of several siphonophore, cubozoan and scyphozoan jellyfish, which are mainly involved in the envenomation of bathers and sea-workers. Therefore, the aim of this paper is to review the scientific literature concerning the hemolytic venoms from cnidarian jellyfish taking into consideration their importance in human pathology as well as health implications and possible therapeutic measures. PMID:25386336

Mariottini, Gian Luigi

2014-01-01

168

Feeding and asexual reproduction of the jellyfish Sarsia gemmifera in response to resource enrichment  

Microsoft Academic Search

Jellyfish are ubiquitous predators in marine pelagic environments and can sometimes control their zooplankton prey populations. Recent considerations of the fertilization of entire food webs in coastal areas make it important to investigate the response of jellyfish to resource enrichment. We investigated feeding, assimilation and life history parameters in the hydromedusa species Sarsia gemmifera. S. gemmifera was able to ingest

Herwig Stibor; Nils Tokle

2003-01-01

169

Nucleotide sequences of 5S rRNAs from four jellyfishes.  

PubMed

The nucleotide sequences of 5S rRNAs from four jellyfishes, Spirocodon saltatrix, Nemopsis dofleini, Aurelia aurita and Chrysaora quinquecirrha have been determined. The sequences are highly similar to each other. A fairly high similarity was also found between these jellyfishes and a sea anemone, Anthopleura japonica. PMID:6130512

Hori, H; Ohama, T; Kumazaki, T; Osawa, S

1982-11-25

170

Nucleotide sequences of 5S rRNAs from four jellyfishes.  

PubMed Central

The nucleotide sequences of 5S rRNAs from four jellyfishes, Spirocodon saltatrix, Nemopsis dofleini, Aurelia aurita and Chrysaora quinquecirrha have been determined. The sequences are highly similar to each other. A fairly high similarity was also found between these jellyfishes and a sea anemone, Anthopleura japonica. PMID:6130512

Hori, H; Ohama, T; Kumazaki, T; Osawa, S

1982-01-01

171

CONTINUATION AND EXPANSION OF DOCKWATCH VOLUNTEER REPORTING SYSTEMS FOR NUISANCE AND INVASIVE JELLYFISH  

EPA Science Inventory

Gather data, using a citizens' monitoring network to track jellyfish occurrence in the northern Gulf of Mexico. The dtat will be incorporated into the database that will establish better linkages between jellyfish, transport and bloom cycles. The project will also be used imp...

172

Interannual variability in abundance of North Sea jellyfish and links to the North Atlantic Oscillation  

Microsoft Academic Search

Pronounced interannual variability in the abundance of medusae of the jellyfish species Aurelia aurita, Cyanea lamarckii, and Cyanea capillata (Phylum Cnidaria, Class Scyphozoa) in the North Sea was evident in data arising from the International Council for the Exploration of the Seas International 0-group Gadoid Surveys between 1971 and 1986. Possible climatic forcing of jellyfish abundance, via the North Atlantic

Christopher P. Lynam; Stephen J. Hay; Andrew S. Brierley

2004-01-01

173

Ecological and economic implications of a tropical jellyfish invader in the Gulf of Mexico  

Microsoft Academic Search

A large population of a previously unreported jellyfish occurred across the northern Gulf of Mexico (USA) from May through September of 2000. The jellyfish, identified as Phyllorhiza punctata by von Lendenfeld (1884), is not indigenous to the Gulf of Mexico or to the Atlantic Basin. Current theory states that this invasive species was introduced into the Atlantic from the Pacific

William M. Graham; Daniel L. Martin; Darryl L. Felder; Vernon L. Asper; Harriet M. Perry

2003-01-01

174

JELLYFISH AGGREGATIONS AND LEATHERBACK TURTLE FORAGING PATTERNS IN A TEMPERATE COASTAL ENVIRONMENT  

Microsoft Academic Search

Leatherback turtles (Dermochelys coriacea) are obligate predators of gelatinous zooplankton. However, the spatial relationship between predator and prey remains poorly understood beyond sporadic and localized reports. To examine how jellyfish (Phylum Cnidaria: Orders Semaeostomeae and Rhizostomeae) might drive the broad-scale distribution of this wide ranging species, we employed aerial surveys to map jellyfish throughout a temperate coastal shelf area bordering

Jonathan D. R. Houghton; Thomas K. Doyle; Mark W. Wilson; John Davenport; Graeme C. Hays

2006-01-01

175

A biomimetic jellyfish robot based on ionic polymer metal composite actuators  

Microsoft Academic Search

A biomimetic jellyfish robot based on ionic polymer metal composite actuators was fabricated and activated to mimic real locomotive behavior with pulse and recovery processes. To imitate the curved shape of the jellyfish, a thermal treatment was applied to obtain a permanent initial deformation of a hemispherical form. The bio-inspired input signal was generated for mimicking real locomotion of the

Sung-Weon Yeom; Il-Kwon Oh

2009-01-01

176

Cytotoxicity and hemolytic activity of jellyfish Nemopilema nomurai (Scyphozoa: Rhizostomeae) venom  

Microsoft Academic Search

The recent bloom of a giant jellyfish Nemopilema nomurai has caused a danger to sea bathers and fishery damages in the waters of China, Korea, and Japan. The present study investigated the cytotoxic and hemolytic activities of crude venom extract of N. nomurai using a number of in vitro assays. The jellyfish venom showed a much higher cytotoxic activity in

Changkeun Kang; Al Munawir; Mijin Cha; Eun-Tae Sohn; Hyunkyoung Lee; Jong-Shu Kim; Won Duk Yoon; Donghyun Lim; Euikyung Kim

2009-01-01

177

Stings of edible jellyfish ( Rhopilema hispidum, Rhopilema esculentum and Nemopilema nomurai) in Japanese waters  

Microsoft Academic Search

Three edible jellyfish Rhopilema hispidum, R. esculentum and Nemopilema nomurai are virulent to humans. We monitored one patient that was stung sequentially by these three species of jellyfish. The first species caused a persistent eruption, the second produced significant pruritus and the last induced only cutaneous symptoms rather than severe systemic disorders reported for its Chinese counterpart. The lesions of

M. Kawahara; S. Uye; J. Burnett; H. Mianzan

2006-01-01

178

Signatures of active and passive optimized Lévy searching in jellyfish.  

PubMed

Some of the strongest empirical support for Lévy search theory has come from telemetry data for the dive patterns of marine predators (sharks, bony fishes, sea turtles and penguins). The dive patterns of the unusually large jellyfish Rhizostoma octopus do, however, sit outside of current Lévy search theory which predicts that a single search strategy is optimal. When searching the water column, the movement patterns of these jellyfish change over time. Movement bouts can be approximated by a variety of Lévy and Brownian (exponential) walks. The adaptive value of this variation is not known. On some occasions movement pattern data are consistent with the jellyfish prospecting away from a preferred depth, not finding an improvement in conditions elsewhere and so returning to their original depth. This 'bounce' behaviour also sits outside of current Lévy walk search theory. Here, it is shown that the jellyfish movement patterns are consistent with their using optimized 'fast simulated annealing'--a novel kind of Lévy walk search pattern--to locate the maximum prey concentration in the water column and/or to locate the strongest of many olfactory trails emanating from more distant prey. Fast simulated annealing is a powerful stochastic search algorithm for locating a global maximum that is hidden among many poorer local maxima in a large search space. This new finding shows that the notion of active optimized Lévy walk searching is not limited to the search for randomly and sparsely distributed resources, as previously thought, but can be extended to embrace other scenarios, including that of the jellyfish R. octopus. In the presence of convective currents, it could become energetically favourable to search the water column by riding the convective currents. Here, it is shown that these passive movements can be represented accurately by Lévy walks of the type occasionally seen in R. octopus. This result vividly illustrates that Lévy walks are not necessarily the result of selection pressures for advantageous searching behaviour but can instead arise freely and naturally from simple processes. It also shows that the family of Lévy walkers is vastly larger than previously thought and includes spores, pollens, seeds and minute wingless arthropods that on warm days disperse passively within the atmospheric boundary layer. PMID:25100323

Reynolds, Andy M

2014-10-01

179

3D simulations of self-propelled, reconstructed jellyfish using vortex methods  

E-print Network

We present simulations of the vortex dynamics associated with the self-propelled motion of jellyfish. The geometry is obtained from image segmentation of video recordings from live jellyfish. The numerical simulations are performed using three-dimensional viscous, vortex particle methods with Brinkman penalization to impose the kinematics of the jellyfish motion. We study two types of strokes recorded in the experiment1. The first type (stroke A) produces two vortex rings during the stroke: one outside the bell during the power stroke and one inside the bell during the recovery stroke. The second type (stroke B) produces three vortex rings: one ring during the power stroke and two vortex rings during the recovery stroke. Both strokes propel the jellyfish, with stroke B producing the highest velocity. The speed of the jellyfish scales with the square root of the Reynolds number. The simulations are visualized in a fluid dynamics video.

Rasmussen, J T; Storti, F; Koumoutsakos, P; Walther, J H

2009-01-01

180

A biomimetic jellyfish robot based on ionic polymer metal composite actuators  

NASA Astrophysics Data System (ADS)

A biomimetic jellyfish robot based on ionic polymer metal composite actuators was fabricated and activated to mimic real locomotive behavior with pulse and recovery processes. To imitate the curved shape of the jellyfish, a thermal treatment was applied to obtain a permanent initial deformation of a hemispherical form. The bio-inspired input signal was generated for mimicking real locomotion of the jellyfish. The vertical floating displacement and the thrust force of the biomimetic jellyfish robot under various input signals were measured and compared. The present results show that the bio-inspired electrical input signal with pulse-recovery process generates much higher floating velocity of the biomimetic jellyfish robot in comparison with pure sinusoidal excitations. The curved shape of the IPMC actuator through thermal treatments can be successfully applied to mimic the real biomimetic robots with smooth curves.

Yeom, Sung-Weon; Oh, Il-Kwon

2009-08-01

181

Marine stingers in far north Queensland.  

PubMed

Two box jellyfish in particular cause problems in tropical Queensland waters. Chironex fleckeri inhabit calm waters close to the shore between November and May. The venom includes three major components: haemolytic dermatonecrotic and myocardial. The dermatonecrotic toxin causes a ladder pattern of whiplash lesions to the skin which ulcerate become necrotic and heal very slowly over months: Neuromuscular paralysis and cardiovascular collapse may be fatal within minutes of envenomation. Emergency treatment comprises inactivation of stinging capsules by vinegar removal of tentacles analgesia, cardiopulmonary resuscitation and the administration of the specific antivenom. Carukia barnesi ('Irukandji') are found in both coastal and open waters. A patch of erythema with papules at the sting site is characteristically followed 30 min later by the onset of a catecholamine mediated syndrome. Headache and severe abdominal and back pain are usual and may be followed by hypertension, tachyarrhythmias and cardiogenic shock. PMID:8713006

Holmes, J L

1996-05-01

182

The use of pressure immobilization bandages in the first aid management of cubozoan envenomings.  

PubMed

This study is aimed to evaluate whether the application of pressure results in additional release of venom from naturally discharged, vinegar soaked nematocysts of the box jellyfish Chironex fleckeri. The results show that large quantities of venom are expressed with the application of pressures similar to that applied by compression immobilization bandages. The volume of venom expressed by this pressure was similar to the quantity expressed upon initial natural discharge of the nematocysts. The current recommended practice of applying PIB to cubozoan stings might worsen the envenomation. As the existing data now show that PIB may be detrimental to victims envenomed by cubozoans, we suggest that the current practice of the use of PIB in cubozoan envenomings be discarded until there is direct experimental evidence to support its use. PMID:12368122

Seymour, Jamie; Carrette, Teresa; Cullen, Paul; Little, Mark; Mulcahy, Richard F; Pereira, Peter L

2002-10-01

183

Biomass of Scyphozoan Jellyfish, and Its Spatial Association with 0-Group Fish in the Barents Sea  

E-print Network

An 0-group fish survey is conducted annually in the Barents Sea in order to estimate fish population abundance. Data on jellyfish by-catch have been recorded since 1980, although this dataset has never been analysed. In recent years, however, the ecological importance of jellyfish medusae has become widely recognized. In this paper the biomass of jellyfish (medusae) in 0–60 m depths is calculated for the period 1980–2010. During this period the climate changed from cold to warm, and changes in zooplankton and fish distribution and abundance were observed. This paper discusses the less well known ecosystem component; jellyfish medusae within the Phylum Cnidaria, and their spatial and temporal variation. The long term average was ca. 9610 8 kg, with some years showing biomasses in excess of 5610 9 kg. The biomasses were low during 1980s, increased during 1990s, and were highest in early 2000s with a subsequent decline. The bulk of the jellyfish were observed in the central parts of the Barents Sea, which is a core area for most 0-group fishes. Jellyfish were associated with haddock in the western area, with haddock and herring in the central and coastal area, and with capelin in the northern area of the Barents Sea. The jellyfish were present in the temperature interval 1uC,T,10uC, with peak densities at ca. 5.5uC, and the greatest proportion of the jellyfish occurring between 4.0–7.0uC. It seems that the ongoing warming trend may be favourable for Barents Sea jellyfish medusae; however their biomass has showed a recent moderate decline during years with record high temperatures in the Barents Sea. Jellyfish are undoubtedly an important component of the Barents

Elena Eriksen; Dmitry Prozorkevich; R Trofimov; Daniel Howell

2011-01-01

184

Impact of stinging jellyfish proliferations along south Italian coasts: human health hazards, treatment and social costs.  

PubMed

Stinging jellyfish outbreaks represent a health hazard, causing contact dermatitis and systemic reactions. This study investigated the epidemiology, severity, and treatment protocols of jellyfish stings in a coastal area with high tourist development and frequent stinging jellyfish outbreaks of the central Mediterranean (Salento, Southern Italy), and the associated costs for the Italian National Health Service. In 2007-2011, 1,733 bathers (mostly children and females) sought medical assistance following jellyfish stings, the main cause of human pathologies due to contact with marine organisms. The majority of events were reported in the years 2007-2009, whereas the occurrence of cnidarian jellyfish outbreaks has been increasingly reported in the same area since summer 2010. Most symptoms were limited to local and cutaneous reactions; conversely, 8.7% of cases evoked complications, mainly due to allergic reactions. The main drugs used were corticosteroids, locally applied and systemic (46% and 43%, respectively), and with ammonia (74%) as the main non-pharmacological treatment. The estimated cost of jellyfish-related first-aid services along the Salento coastline over the 5-year period was approximately 400,000 Euros. Therefore the management of jellyfish outbreak phenomena need coordinated research efforts towards a better understanding of underlying ecological mechanisms, together with the adoption of effective prevention policy, mitigation strategies, and appropriate planning of health services at tourist hot spots. PMID:24583831

De Donno, Antonella; Idolo, Adele; Bagordo, Francesco; Grassi, Tiziana; Leomanni, Alessandro; Serio, Francesca; Guido, Marcello; Canitano, Mariarita; Zampardi, Serena; Boero, Ferdinando; Piraino, Stefano

2014-03-01

185

Impact of Stinging Jellyfish Proliferations along South Italian Coasts: Human Health Hazards, Treatment and Social Costs  

PubMed Central

Stinging jellyfish outbreaks represent a health hazard, causing contact dermatitis and systemic reactions. This study investigated the epidemiology, severity, and treatment protocols of jellyfish stings in a coastal area with high tourist development and frequent stinging jellyfish outbreaks of the central Mediterranean (Salento, Southern Italy), and the associated costs for the Italian National Health Service. In 2007–2011, 1,733 bathers (mostly children and females) sought medical assistance following jellyfish stings, the main cause of human pathologies due to contact with marine organisms. The majority of events were reported in the years 2007–2009, whereas the occurrence of cnidarian jellyfish outbreaks has been increasingly reported in the same area since summer 2010. Most symptoms were limited to local and cutaneous reactions; conversely, 8.7% of cases evoked complications, mainly due to allergic reactions. The main drugs used were corticosteroids, locally applied and systemic (46% and 43%, respectively), and with ammonia (74%) as the main non-pharmacological treatment. The estimated cost of jellyfish-related first-aid services along the Salento coastline over the 5-year period was approximately 400,000 Euros. Therefore the management of jellyfish outbreak phenomena need coordinated research efforts towards a better understanding of underlying ecological mechanisms, together with the adoption of effective prevention policy, mitigation strategies, and appropriate planning of health services at tourist hot spots. PMID:24583831

De Donno, Antonella; Idolo, Adele; Bagordo, Francesco; Grassi, Tiziana; Leomanni, Alessandro; Serio, Francesca; Guido, Marcello; Canitano, Mariarita; Zampardi, Serena; Boero, Ferdinando; Piraino, Stefano

2014-01-01

186

Evaluation of the effects of various chemicals on discharge of and pain caused by jellyfish nematocysts.  

PubMed

Jellyfish tentacles in contact with human skin can produce pain swelling and redness. The pain is due to discharge of jellyfish nematocysts and associated toxins and discharge can be caused by a variety of mechanical and chemical stimuli. A series of tests were carried out with chemicals traditionally used to treat jellyfish stings e.g. acetic acid ammonia meat tenderizer baking soda and urea to determine if these chemicals stimulated or inhibited nematocyst discharge and if they brought relief to testers who were exposed to jellyfish tentacles. Chrysaora quinquecirrha (sea nettle) Chiropsalmus quadrumanus (sea wasp) and Physalia physalis (Portuguese man-of-war) were used in the study. It was found that many of the chemicals traditionally used to treat jellyfish stings stimulated nematocyst discharge and did not relieve the pain. However there was immediate relief when a common anesthetic lidocaine was sprayed on the skin of testers in contact with jellyfish tentacles. Initial exposure of tentacle suspensions to lidocaine prevented the nematocyst discharge by subsequent exposure to acetic acid ethanol ammonia or bromelain. Thus lidocaine in addition to acting as an anesthetic on skin in contact with jellyfish tentacles inhibited nematocyst discharge possibly by blocking sodium and/or calcium channels of the nematocytes. PMID:20116454

Birsa, Laura M; Verity, Peter G; Lee, Richard F

2010-05-01

187

Stings of edible jellyfish (Rhopilema hispidum, Rhopilema esculentum and Nemopilema nomurai) in Japanese waters.  

PubMed

Three edible jellyfish Rhopilema hispidum, R. esculentum and Nemopilema nomurai are virulent to humans. We monitored one patient that was stung sequentially by these three species of jellyfish. The first species caused a persistent eruption, the second produced significant pruritus and the last induced only cutaneous symptoms rather than severe systemic disorders reported for its Chinese counterpart. The lesions of these jellyfish species are characteristic and common in workers harvesting medusae. There is no significant incidence of symptoms by ingesting these animals. PMID:16962626

Kawahara, M; Uye, S; Burnett, J; Mianzan, H

2006-11-01

188

J3-crystallin of the jellyfish lens: Similarity to saposins  

PubMed Central

J3-crystallin, one of the three major eye-lens proteins of the cubomedusan jellyfish (Tripedalia cystophora), shows similarity to vertebrate saposins, which are multifunctional proteins that bridge lysosomal hydrolases to lipids and activate enzyme activity. Sequence alignment of deduced J3-crystallin indicates two saposin-like motifs arranged in tandem, each containing six cysteines characteristic of this protein family. The J3-crystallin cDNA encodes a putative precursor analogous to vertebrate prosaposins. The J3-crystallin gene has seven exons, with exons 2–4 encoding the protein. Exon 3 encodes a circularly permutated saposin motif, called a swaposin, found in plant aspartic proteases. J3-crystallin RNA was found in the cubomedusan lens, statocyst, in bands radiating from the pigmented region of the ocellus, in the tentacle tip by in situ hybridization, and in the embryo and larva by reverse transcription–PCR. Our data suggest a crystallin role for the multifunctional saposin protein family in the jellyfish lens. This finding extends the gene sharing evolutionary strategy for lens crystallins to the cnidarians and indicates that the putative primordial saposin/swaposin J3-crystallin reflects both the chaperone and enzyme connections of the vertebrate crystallins. PMID:11675486

Piatigorsky, Joram; Norman, Barbara; Dishaw, Larry J.; Kos, Lidia; Horwitz, Joseph; Steinbach, Peter J.; Kozmik, Zbynek

2001-01-01

189

[Olindias sambaquiensis jellyfish sting. Analysis of 49 cases].  

PubMed

Olindias sambaquiensis jellyfish sting occurs frequently in Buenos Aires province coast beaches. Among five hundred and one thousand stings by jellyfish are reported each season at Monte Hermoso, a beach village in the South of Buenos Aires province. The skin damage provoked because of its highly irritant effect poses a serious issue related to tourism development. A total number of 49 cases that were examined during the first hour after the sting were enrolled in Monte Hermoso during January 1998. Twenty eight were males (57.1%). The average age was 16 ± 4.1 (range 5-80). Of them, 54% showed linear erythema-edematous lesions, 28% showed predominantly erythematous lesions, and in 18% the injuries were erythema-edematous plaques. In 73% of the cases the lesions were located in lower limbs. We had hereby redefined cutaneous lesions produced by O. sambaquiensis, its evolution, its dimensions and most frequent localizations. Besides, it has been typified and quantified the pain it provokes and other signs and symptoms that go with the sting during the posterior hour, during the first 24 hours, and after 30 days. We described the therapeutic conducts used in our coasts and we assessed the effectiveness of some of them in pain control, and finally we propose a therapeutic scheme for this sting. PMID:23089113

Mosovich, Juan H; Young, Pablo

2012-01-01

190

A tissue-engineered jellyfish with biomimetic propulsion  

PubMed Central

Reverse engineering of biological form and function requires hierarchical design over several orders of space and time. Recent advances in the mechanistic understanding of biosynthetic compound materials1–3, computer-aided design approaches in molecular synthetic biology4,5 and traditional soft robotics6,7, and increasing aptitude in generating structural and chemical microenvironments that promote cellular self-organization8–10 have enhanced the ability to recapitulate such hierarchical architecture in engineered biological systems. Here we combined these capabilities in a systematic design strategy to reverse engineer a muscular pump. We report the construction of a freely swimming jellyfish from chemically dissociated rat tissue and silicone polymer as a proof of concept. The constructs, termed ‘medusoids’, were designed with computer simulations and experiments to match key determinants of jellyfish propulsion and feeding performance by quantitatively mimicking structural design, stroke kinematics and animal-fluid interactions. The combination of the engineering design algorithm with quantitative benchmarks of physiological performance suggests that our strategy is broadly applicable to reverse engineering of muscular organs or simple life forms that pump to survive. PMID:22820316

Nawroth, Janna C; Lee, Hyungsuk; Feinberg, Adam W; Ripplinger, Crystal M; McCain, Megan L; Grosberg, Anna; Dabiri, John O; Parker, Kevin Kit

2014-01-01

191

Cell Proliferation in Cubozoan Jellyfish Tripedalia cystophora and Alatina moseri  

PubMed Central

Cubozoans (box jellyfish) undergo remarkable body reorganization throughout their life cycle when, first, they metamorphose from swimming larvae to sessile polyps, and second, through the metamorphosis from sessile polyps to free swimming medusae. In the latter they develop complex structures like the central nervous system (CNS) and visual organs. In the present study several aspects of cell proliferation at different stages of the life cycle of the box jellyfish Tripedalia cystophora and Alatina moseri have been examined through in vivo labeling of cells in the synthetic phase (S phase) of the cell cycle. Proliferation zones were found in metamorphosing polyps, as well as in juvenile medusae, where both the rhopalia and pedalia have enhanced rates of proliferation. The results also indicate a rather fast cell turnover in the rhopalia including the rhopalial nervous system (RNS). Moreover, T. cystophora showed diurnal pattern of cell proliferation in certain body parts of the medusa, with higher proliferation rates at nighttime. This is true for two areas in close connection with the CNS: the stalk base and the rhopalia. PMID:25047715

Gurska, Daniela; Garm, Anders

2014-01-01

192

A tissue-engineered jellyfish with biomimetic propulsion.  

PubMed

Reverse engineering of biological form and function requires hierarchical design over several orders of space and time. Recent advances in the mechanistic understanding of biosynthetic compound materials, computer-aided design approaches in molecular synthetic biology 4,5 and traditional soft robotics, and increasing aptitude in generating structural and chemical micro environments that promote cellular self-organization have enhanced the ability to recapitulate such hierarchical architecture in engineered biological systems. Here we combined these capabilities in a systematic design strategy to reverse engineer a muscular pump. We report the construction of a freely swimming jellyfish from chemically dissociated rat tissue and silicone polymer as a proof of concept. The constructs, termed 'medusoids', were designed with computer simulations and experiments to match key determinants of jellyfish propulsion and feeding performance by quantitatively mimicking structural design, stroke kinematics and animal-fluid interactions. The combination of the engineering design algorithm with quantitative benchmarks of physiological performance suggests that our strategy is broadly applicable to reverse engineering of muscular organs or simple life forms that pump to survive. PMID:22820316

Nawroth, Janna C; Lee, Hyungsuk; Feinberg, Adam W; Ripplinger, Crystal M; McCain, Megan L; Grosberg, Anna; Dabiri, John O; Parker, Kevin Kit

2012-08-01

193

Box jellyfish envenomation: case report of effective lemon and oil emulsion treatment.  

PubMed

Box jellyfish are highly venomous and numerous possible treatments for envenomation have already been reported in the published literature. The hand of a 55-year-old scuba diver was stung in the Gulf of Guinea resulting in two crops of coalescing vesicles with intense pain and lymphadenopathy. Traditional therapies such as hot water, cold packs and acetic acid were ineffective. Symptoms were rapidly relieved after the application of a lemon-oil emulsion balm. Treatments for jellyfish envenomation generally aim to either denature the jellyfish venom or prevent the discharge of the venom. Lemon-oil emulsion therapy has not yet been reported in the published literature but may be an economical and novel treatment for box jellyfish envenomation. PMID:24334401

Hamann, Carsten R; Hamann, Dathan; Richardson, Clare; Seeburger, Jack

2014-04-01

194

Energy requirements and food supplies of ctenophores and jellyfish in the Patuxent River estuary  

Microsoft Academic Search

Interpretation of published data for the Patuxent River, Maryland, indicates that for most of the year the total biomass of\\u000a phytoplankton and zooplankton was inadequate to meet the minimum energy needs of ctenophores and jellyfish.

R. J. Miller; Richard B. Williams

1972-01-01

195

Jellyfish blooms result in a major microbial respiratory sink of carbon in marine systems  

PubMed Central

Jellyfish blooms occur in many estuarine and coastal regions and may be increasing in their magnitude and extent worldwide. Voracious jellyfish predation impacts food webs by converting large quantities of carbon (C), fixed by primary producers and consumed by secondary producers, into gelatinous biomass, which restricts C transfer to higher trophic levels because jellyfish are not readily consumed by other predators. In addition, jellyfish release colloidal and dissolved organic matter (jelly-DOM), and could further influence the functioning of coastal systems by altering microbial nutrient and DOM pathways, yet the links between jellyfish and bacterioplankton metabolism and community structure are unknown. Here we report that jellyfish released substantial quantities of extremely labile C-rich DOM, relative to nitrogen (25.6 ± 31.6 C:1N), which was quickly metabolized by bacterioplankton at uptake rates two to six times that of bulk DOM pools. When jelly-DOM was consumed it was shunted toward bacterial respiration rather than production, significantly reducing bacterial growth efficiencies by 10% to 15%. Jelly-DOM also favored the rapid growth and dominance of specific bacterial phylogenetic groups (primarily ?-proteobacteria) that were rare in ambient waters, implying that jelly-DOM was channeled through a small component of the in situ microbial assemblage and thus induced large changes in community composition. Our findings suggest major shifts in microbial structure and function associated with jellyfish blooms, and a large detour of C toward bacterial CO2 production and away from higher trophic levels. These results further suggest fundamental transformations in the biogeochemical functioning and biological structure of food webs associated with jellyfish blooms. PMID:21646531

Condon, Robert H.; Steinberg, Deborah K.; del Giorgio, Paul A.; Bouvier, Thierry C.; Bronk, Deborah A.; Graham, William M.; Ducklow, Hugh W.

2011-01-01

196

Stable isotope and fatty acid tracers in energy and nutrient studies of jellyfish: a review  

Microsoft Academic Search

Studies of the trophic ecology of gelatinous zooplankton have predominantly employed gut content analyses and grazing experiments.\\u000a These approaches record only what is consumed rather than what is assimilated by the jellyfish, only provide evidence of recent\\u000a feeding, and unless digestion rates of different prey are known, may provide biased estimates of the relative importance of\\u000a different prey to jellyfish

K. A. Pitt; R. M. Connolly; T. Meziane

197

Stable isotope and fatty acid tracers in energy and nutrient studies of jellyfish: a review  

Microsoft Academic Search

Studies of the trophic ecology of gelatinous zooplankton have predominantly employed gut content analyses and grazing experiments.\\u000a These approaches record only what is consumed rather than what is assimilated by the jellyfish, only provide evidence of recent\\u000a feeding, and unless digestion rates of different prey are known, may provide biased estimates of the relative importance of\\u000a different prey to jellyfish

K. A. Pitt; R. M. Connolly; T. Meziane

2009-01-01

198

Vulnerability of larval herring ( Clupea harengus pallasi ) to capture by the jellyfish Aequorea victoria  

Microsoft Academic Search

Gut-content analysis of Aequorea victoria collected in Kulleet Bay, Vancouver Island, British Columbia, Canada, in 1983, showed that the jellyfish consumed herring (Clupea harengus pallasi) larvae, primarily yolksac [?8mm notochord length (NL)] and post-yolksac larvae (?12mm NL). Behavioral experiments with laboratory-reared larvae showed that the ability to escape after contact with a jellyfish tentacle increased dramatically from yolksac through pre-metamorphic

J. E. Purcell; T. D. Siferd; J. B. Marliave

1987-01-01

199

Jack mackerel Trachurus japonicus juveniles use jellyfish for predator avoidance and as a prey collector  

Microsoft Academic Search

Juveniles of carangid fishes including jack mackerel Trachurus japonicus are known to associate with jellyfishes. The function of this association behavior was studied through rearing experiments\\u000a and underwater visual observations. Association behavior of jack mackerel with moon jellyfish in experimental tanks was more\\u000a frequent in the presence compared to the absence of predators (chub mackerel Scomber japonicus). In the experimental

Reiji Masuda; Yoh Yamashita; Michiya Matsuyama

2008-01-01

200

Measurement of swimming speed of giant jellyfish Nemopilema nomurai using acoustics and visualization analysis  

Microsoft Academic Search

A species of giant jellyfish, Nemopilema nomurai, which has appeared only recently in the East China Sea, is an emerging nuisance in the northeastern region of Asia because\\u000a of its extensive damage to fisheries. Until now, the biomass estimates of these jellyfish have mainly been obtained using\\u000a trawl sampling and sighting survey methods. However, it is also necessary to determine

Kyounghoon Lee; Bong-Seong Bae; In-Ok Kim; Won-Deuk Yoon

2010-01-01

201

Human forcing of the copepod–fish–jellyfish triangular trophic relationship  

Microsoft Academic Search

Copepods, the most abundant planktonic metazoans, constitute an intermediate trophic position between phytoplankton and higher\\u000a trophic-level animals such as fish and jellyfish. Fish and jellyfish are adversaries because they often compete for prey copepods\\u000a and also can be prey of each other. The classical food chain represented by phytoplankton–copepod–fish is the main process\\u000a leading to efficient and sustainable production of

Shin-ichi Uye

2011-01-01

202

Influence of decomposing jellyfish on the sediment oxygen demand and nutrient dynamics  

Microsoft Academic Search

Jellyfish populations can grow rapidly to attain large biomasses and therefore can represent significant stocks of carbon\\u000a and nitrogen in the ecosystem. Blooms are also generally short-lived, lasting for just weeks or months, after which time the\\u000a population can decline rapidly, sink to the bottom and decompose. The influence of decomposing jellyfish (Catostylus mosaicus, Scyphozoa) on benthic dissolved oxygen and

Elizabeth Jane West; David Thomas Welsh; Kylie Anne Pitt

2009-01-01

203

Influence of decomposing jellyfish on the sediment oxygen demand and nutrient dynamics  

Microsoft Academic Search

Jellyfish populations can grow rapidly to attain large biomasses and therefore can represent significant stocks of carbon\\u000a and nitrogen in the ecosystem. Blooms are also generally short-lived, lasting for just weeks or months, after which time the\\u000a population can decline rapidly, sink to the bottom and decompose. The influence of decomposing jellyfish (Catostylus mosaicus, Scyphozoa) on benthic dissolved oxygen and

Elizabeth Jane West; David Thomas Welsh; Kylie Anne Pitt

204

Jellyfish as vectors of bacterial disease for farmed salmon (Salmo salar).  

PubMed

Swarms or blooms of jellyfish are increasingly problematic and can result in high mortality rates of farmed fish. Small species of jellyfish, such as Phialella quadrata (13 mm in diameter), are capable of passing through the mesh of sea cages and being sucked into the mouth of fish during respiration. Results of the current study show that the initial damage to gills of farmed Atlantic salmon, likely produced by nematocyst-derived toxins from the jellyfish, was compounded by secondary bacterial infection with Tenacibaculum maritimum. Results also demonstrate that these filamentous bacteria were present on the mouth of the jellyfish and that their DNA sequences were almost identical to those of bacteria present on the salmon gills. This suggests that the bacterial lesions were not the result of an opportunistic infection of damaged tissue, as previously thought. Instead, P. quadrata is probably acting as a vector for this particular bacterial pathogen, and it is the first time that evidence to support such a link has been presented. No prior literature describing the presence of bacteria associated with jellyfish, except studies about their decay, could be found. It is not known if all jellyfish of this and other species carry similar bacteria or the relationship to each other. Their source, the role they play under other circumstances, and indeed whether the jellyfish were themselves diseased are also not known. The high proteolytic capabilities of T. maritimum mean that partially digested gill tissues were readily available to the jellyfish, which rely heavily on intracellular digestion for their nutrition. PMID:20453210

Ferguson, Hugh W; Delannoy, Christian M J; Hay, Stephen; Nicolson, James; Sutherland, David; Crumlish, Margaret

2010-05-01

205

Comparison of telomere length among different life cycle stages of the jellyfish Cassiopea andromeda  

Microsoft Academic Search

The polyp (scyphistoma) of the jellyfish Cassiopea andromeda reproduces asexually repeatedly, while the medusa, the sexually reproducing stage, exhibits a relatively shorter life span.\\u000a As a first step to understand the mechanism behind the differences in the life spans of the polyp and medusa stages of the\\u000a jellyfish, we compared the lengths of the telomere region of one targeted chromosome

Michiko C. Ojimi; Michio Hidaka

2010-01-01

206

Jellyfish blooms result in a major microbial respiratory sink of carbon in marine systems.  

PubMed

Jellyfish blooms occur in many estuarine and coastal regions and may be increasing in their magnitude and extent worldwide. Voracious jellyfish predation impacts food webs by converting large quantities of carbon (C), fixed by primary producers and consumed by secondary producers, into gelatinous biomass, which restricts C transfer to higher trophic levels because jellyfish are not readily consumed by other predators. In addition, jellyfish release colloidal and dissolved organic matter (jelly-DOM), and could further influence the functioning of coastal systems by altering microbial nutrient and DOM pathways, yet the links between jellyfish and bacterioplankton metabolism and community structure are unknown. Here we report that jellyfish released substantial quantities of extremely labile C-rich DOM, relative to nitrogen (25.6 ± 31.6 C:1N), which was quickly metabolized by bacterioplankton at uptake rates two to six times that of bulk DOM pools. When jelly-DOM was consumed it was shunted toward bacterial respiration rather than production, significantly reducing bacterial growth efficiencies by 10% to 15%. Jelly-DOM also favored the rapid growth and dominance of specific bacterial phylogenetic groups (primarily ?-proteobacteria) that were rare in ambient waters, implying that jelly-DOM was channeled through a small component of the in situ microbial assemblage and thus induced large changes in community composition. Our findings suggest major shifts in microbial structure and function associated with jellyfish blooms, and a large detour of C toward bacterial CO(2) production and away from higher trophic levels. These results further suggest fundamental transformations in the biogeochemical functioning and biological structure of food webs associated with jellyfish blooms. PMID:21646531

Condon, Robert H; Steinberg, Deborah K; del Giorgio, Paul A; Bouvier, Thierry C; Bronk, Deborah A; Graham, William M; Ducklow, Hugh W

2011-06-21

207

A Randomized, Controlled Field Trial for the Prevention of Jellyfish Stings With a Topical Sting Inhibitor  

PubMed Central

Background Jellyfish stings are a common occurrence among ocean goers worldwide with an estimated 150 million envenomations annually. Fatalities and hospitalizations occur annually, particularly in the Indo-Pacific regions. A new topical jellyfish sting inhibitor based on the mucous coating of the clown fish prevents 85% of jellyfish stings in laboratory settings. The field effectiveness is unknown. The objective is to evaluate the field efficacy of the jellyfish sting inhibitor, Safe Sea™. Methods A double-blind, randomized, placebo-controlled trial occurred at the Dry Tortugas National Park, FL, USA and Sapodilla Cayes, Belize. Participants were healthy volunteers planning to snorkel for 30 to 45 minutes. Ten minutes prior to swimming, each participant was directly observed applying a blinded sample of Safe Sea (Nidaria Technology Ltd, Jordan Valley, Israel) to one side of their body and a blinded sample of Coppertone® (Schering-Plough, Kenilworth, NJ, USA) to the contralateral side as placebo control. Masked 26 g samples of both Safe Sea SPF15 and Coppertone® SPF15 were provided in identical containers to achieve 2 mg/cm2 coverage. Sides were randomly chosen by participants. The incidence of jellyfish stings was the main outcome measure. This was assessed by participant interview and examination as subjects exited the water. Results A total of 82 observed water exposures occurred. Thirteen jellyfish stings occurred during the study period for a 16% incidence. Eleven jellyfish stings occurred with placebo, two with the sting inhibitor, resulting in a relative risk reduction of 82% (95% confidence interval: 21%–96%; p = 0.02). No seabather’s eruption or side effects occurred. Conclusions Safe Sea is a topical barrier cream effective at preventing >80% jellyfish stings under real-world conditions. PMID:16706948

Boulware, David R.

2007-01-01

208

Irukandji jellyfish polyps exhibit tolerance to interacting climate change stressors.  

PubMed

Increasing ocean temperatures and strengthening boundary currents have caused the poleward migration of many marine species. Cubozoan jellyfish known to cause Irukandji syndrome have historically been confined to tropical waters but may be expanding into subtropical regions. Here, we examine the interactive effects of warming and acidification on the population dynamics of polyps of an Irukandji jellyfish, Alatina nr mordens, and the formation of statoliths in newly metamorphosed medusae, to determine if this jellyfish could tolerate future conditions predicted for southeast Queensland (SEQ), Australia. Two experiments, examining the orthogonal factors of temperature and pH, were undertaken. Experiment 1 mimicked the current, ca. 2050 and ca. 2100 summer temperature and pH conditions predicted for SEQ using A1F1 scenarios (temperature: 25, 27, 29 °C; pH: 7.9, 7.8, 7.6) and Experiment 2 mimicked current and future winter conditions (18 and 22 °C, pH 7.9, 7.8, 7.6). All polyps in Experiment 1 survived and budded. Fewer polyps budded in the lower pH treatments; however, patterns varied slightly among temperature treatments. Statoliths at pH 7.6 were 24% narrower than those at pH 7.8 and 7.9. Most polyps survived the winter conditions mimicked by Experiment 2 but only polyps in the 22 °C, pH 7.9 treatment increased significantly. The current absence of A. nr mordens medusae in SEQ, despite the polyps' ability to tolerate the current temperature and pH conditions, suggests that ecological, rather than abiotic factors currently limit their distribution. Observations that budding was lower under low pH treatments suggest that rates of asexual reproduction will likely be much slower in the future. We consider that A. nr mordens polyps are likely to tolerate future conditions but are unlikely to thrive in the long term. However, if polyps can overcome potential ecological boundaries and acidification proceeds slowly A. nr mordens could expand polewards in the short term. PMID:24323533

Klein, Shannon G; Pitt, Kylie A; Rathjen, Kristen A; Seymour, Jamie E

2014-01-01

209

A jellyfish-like swimming mini-robot actuated by an electromagnetic actuation system  

NASA Astrophysics Data System (ADS)

Among the various kinds of actuations for biomimetic robots, the electromagnetic actuation (EMA) method has been regarded as the one with the most potential. This paper proposes a jellyfish-like swimming mini-robot actuated by an EMA system in three-dimensional (3D) space. The jellyfish-like mini-robot has four flexible fins, each of which is equipped with a permanent magnet for electromagnetic actuation; the robot’s body is 17 mm long and 0.5 mm thick. Our EMA system was able to generate a uniform magnetic field in a desired direction in 3D space, which could bend the fins of the jellyfish-like mini-robot. Therefore, a cyclic change in the uniform magnetic field, in the EMA system, would synchronize the fluctuation of the fins and could generate a propulsion force for the robot, in the desired direction. In order to maximize the propulsion force of the jellyfish-like mini-robot, the waveform and frequency of the input current in the EMA system are optimized. Consequently, our jellyfish-like mini-robot was able to generate maximum propulsion force when a square waveform input current (13 A magnitude and 10 Hz frequency) was applied to the EMA system. Finally, the jellyfish-like mini-robot with the EMA system was able to perform various 3D swimming motions.

Ko, Youngho; Na, Sungyoung; Lee, Youngwoo; Cha, Kyoungrae; Ko, Seong Young; Park, Jongoh; Park, Sukho

2012-05-01

210

Extract from the Zooxanthellate Jellyfish Cotylorhiza tuberculata Modulates Gap Junction Intercellular Communication in  

E-print Network

Abstract: On a global scale, jellyfish populations in coastal marine ecosystems exhibit increasing trends of abundance. High-density outbreaks may directly or indirectly affect human economical and recreational activities, as well as public health. As the interest in biology of marine jellyfish grows, a number of jellyfish metabolites with healthy potential, such as anticancer or antioxidant activities, is increasingly reported. In this study, the Mediterranean “fried egg jellyfish ” Cotylorhiza tuberculata (Macri, 1778) has been targeted in the search forputative valuable bioactive compounds. A medusa extract was obtained, fractionated, characterized by HPLC, GC-MS and SDS-PAGE and assayed for its biological activity on breast cancer cells (MCF-7) and human epidermal keratinocytes (HEKa). The composition of the jellyfish extract included photosynthetic pigments, valuable ?-3 and ?-6 fatty acids, and polypeptides derived either from jellyfish tissues and their algal symbionts. Extract fractions showed antioxidant activity and the ability to affect cell viability and intercellular communication mediated by gap junctions (GJIC) differentially in MCF-7and HEKa cells. A significantly higher cytotoxicity and GJIC enhancement in MCF-7 compared to HEKa cells was recorded. A putative action mechanismMar. Drugs 2013, 11 1729

Human Cell Cultures; Antonella Leone; Raffaella Marina Lecci; Miriana Durante; Stefano Piraino

2013-01-01

211

Characterization and neutralization of Nemopilema nomurai (Scyphozoa: Rhizostomeae) jellyfish venom using polyclonal antibody.  

PubMed

Jellyfish stings have often caused serious health concerns for sea bathers especially in tropical waters. In the coastal areas of Korea, China and Japan, the blooming and stinging accidents of poisonous jellyfish species have recently increased, including Nemopilema nomurai. We have generated a polyclonal antibody against N. nomurai jellyfish venom (NnV) by the immunization of white rabbits with NnV antigen. In the present study, the antibody has been characterized for its neutralizing effect against NnV. At first, the presence of NnV polyclonal antibody has been confirmed from the immunized rabbit serum by Enzyme linked immunosorbent assay (ELISA). Then, the neutralizing activities of the polyclonal antibody have been investigated using cell-based toxicity test, hemolysis assay, and mice lethality test. When the polyclonal antibody was preincubated with NnV, it shows a high effectiveness in neutralizing the NnV toxicities in a concentration-dependent manner. Moreover, we explored proteomic analyses using 2-D SDS-PAGE and MALDI-TOF mass spectrometry to illustrate the molecular identities of the jellyfish venom. From this, 18 different protein families have been identified as jellyfish venom-derived proteins; the main findings of which are matrix metalloproteinase-14, astacin-like metalloprotease toxin 3 precursor. It is expected that the present results would have contributed to our understandings of the envenomation by N. nomurai, their treatment and some valuable knowledge on the pathological processes of the jellyfish stinging. PMID:24751365

Kang, Changkeun; Han, Dae-Yong; Park, Kwang-Il; Pyo, Min-Jung; Heo, Yunwi; Lee, Hyunkyoung; Kim, Gon Sup; Kim, Euikyung

2014-08-01

212

A simple visual system without neurons in jellyfish larvae.  

PubMed

Earlier detailed studies of cnidarian planula larvae have revealed a simple nervous system but no eyes or identifiable light sensing structures. Here, we describe the planula of a box jellyfish, Tripedalia cystophora, and report that these larvae have an extremely simple organization with no nervous system at all. Their only advanced feature is the presence of 10-15 pigment-cup ocelli, evenly spaced across the posterior half of the larval ectoderm. The ocelli are single cell structures containing a cup of screening pigment filled with presumably photosensory microvilli. These rhabdomeric photoreceptors have no neural connections to any other cells, but each has a well-developed motor-cilium, appearing to be the only means by which light can control the behaviour of the larva. The ocelli are thus self-contained sensory-motor entities, making a nervous system superfluous. PMID:14667350

Nordström, Karin; Wallén, Rita; Seymour, Jamie; Nilsson, Dan

2003-11-22

213

A simple visual system without neurons in jellyfish larvae.  

PubMed Central

Earlier detailed studies of cnidarian planula larvae have revealed a simple nervous system but no eyes or identifiable light sensing structures. Here, we describe the planula of a box jellyfish, Tripedalia cystophora, and report that these larvae have an extremely simple organization with no nervous system at all. Their only advanced feature is the presence of 10-15 pigment-cup ocelli, evenly spaced across the posterior half of the larval ectoderm. The ocelli are single cell structures containing a cup of screening pigment filled with presumably photosensory microvilli. These rhabdomeric photoreceptors have no neural connections to any other cells, but each has a well-developed motor-cilium, appearing to be the only means by which light can control the behaviour of the larva. The ocelli are thus self-contained sensory-motor entities, making a nervous system superfluous. PMID:14667350

Nordström, Karin; Wallén, Rita; Seymour, Jamie; Nilsson, Dan

2003-01-01

214

Clinical toxicology: a tropical Australian perspective.  

PubMed

Tropical Australia has an amazing diversity of venomous fauna, from "the world's most venomous creature," the multi-tentacled (chirodropid) box jellyfish Chironex fleckeri, to aggressive spiders whose venom remains to be characterized. All genera of highly venomous Australasian elapid snakes are present, except for tiger snakes. Most notable is the taipan (Oxyuranus scutellatus), with the most efficient "snap-release" biting mechanism of any snake and venom components causing the full constellation of clinical envenoming features: coagulopathy from fibrinogen depletion (procoagulant), neurotoxicity (predominantly presynaptic neurotoxin) and rhabdomyolysis (myotoxin). Brown snakes (Pseudonaja textilis and P. nuchalis) now account for most snake bite fatalities in Australia, as a result of severe coagulopathy and a poorly defined early scenario of collapse, postulated to be caused by profound hypotension caused by transient myocardial dysfunction associated with prothrombin activation. Other venomous entities include paralyzing ticks, the blue-ringed octopus, stone fish and other marine animals with venomous spines, paralyzing cone shells, and a wide range of jellyfish including Carukia barnesi and possibly other four-tentacled (carybdeid) box jellyfish causing the Irukandji syndrome. PMID:10688264

Currie, B J

2000-02-01

215

Biology and ecology of Irukandji jellyfish (Cnidaria: Cubozoa).  

PubMed

Irukandji stings are a leading occupational health and safety issue for marine industries in tropical Australia and an emerging problem elsewhere in the Indo-Pacific and Caribbean. Their mild initial sting frequently results in debilitating illness, involving signs of sympathetic excess including excruciating pain, sweating, nausea and vomiting, hypertension and a feeling of impending doom; some cases also experience acute heart failure and pulmonary oedema. These jellyfish are typically small and nearly invisible, and their infestations are generally mysterious, making them scary to the general public, irresistible to the media, and disastrous for tourism. Research into these fascinating species has been largely driven by the medical profession and focused on treatment. Biological and ecological information is surprisingly sparse, and is scattered through grey literature or buried in dispersed publications, hampering understanding. Given that long-term climate forecasts tend toward conditions favourable to jellyfish ecology, that long-term legal forecasts tend toward increasing duty-of-care obligations, and that bioprospecting opportunities exist in the powerful Irukandji toxins, there is a clear need for information to help inform global research and robust management solutions. We synthesise and contextualise available information on Irukandji taxonomy, phylogeny, reproduction, vision, behaviour, feeding, distribution, seasonality, toxins, and safety. Despite Australia dominating the research in this area, there are probably well over 25 species worldwide that cause the syndrome and it is an understudied problem in the developing world. Major gaps in knowledge are identified for future research: our lack of clarity on the socio-economic impacts, and our need for time series and spatial surveys of the species, make this field particularly enticing. PMID:24182899

Gershwin, Lisa-ann; Richardson, Anthony J; Winkel, Kenneth D; Fenner, Peter J; Lippmann, John; Hore, Russell; Avila-Soria, Griselda; Brewer, David; Kloser, Rudy J; Steven, Andy; Condie, Scott

2013-01-01

216

Hydrogen-fuel-powered bell segments of biomimetic jellyfish  

NASA Astrophysics Data System (ADS)

Artificial muscles powered by a renewable energy source are desired for joint articulation in bio-inspired autonomous systems. In this study, a robotic underwater vehicle, inspired by jellyfish, was designed to be actuated by a chemical fuel source. The fuel-powered muscles presented in this work comprise nano-platinum catalyst-coated multi-wall carbon nanotube (MWCNT) sheets, wrapped on the surface of nickel-titanium (NiTi) shape memory alloy (SMA). As a mixture of oxygen and hydrogen gases makes contact with the platinum, the resulting exothermic reaction activates the nickel-titanium (NiTi)-based SMA. The MWCNT sheets serve as a support for the platinum particles and enhance the heat transfer due to the high thermal conductivity between the composite and the SMA. A hydrogen and oxygen fuel source could potentially provide higher power density than electrical sources. Several vehicle designs were considered and a peripheral SMA configuration under the robotic bell was chosen as the best arrangement. Constitutive equations combined with thermodynamic modeling were developed to understand the influence of system parameters that affect the overall actuation behavior of the fuel-powered SMA. The model is based on the changes in entropy of the hydrogen and oxygen fuel on the composite actuator within a channel. The specific heat capacity is the dominant factor controlling the width of the strain for various pulse widths of fuel delivery. Both theoretical and experimental strains for different diameter (100 and 150 µm) SMA/MWCNT/Pt fuel-powered muscles with dead weight attached at the end exhibited the highest magnitude under 450 ms of fuel delivery within 1.6 mm diameter conduit size. Fuel-powered bell deformation of 13.5% was found to be comparable to that of electrically powered (29%) and natural jellyfish (42%).

Tadesse, Yonas; Villanueva, Alex; Haines, Carter; Novitski, David; Baughman, Ray; Priya, Shashank

2012-04-01

217

Target organ identification of jellyfish envenomation using systemic and integrative analyses in anesthetized dogs.  

PubMed

Proper treatment of jellyfish envenomed patients can be successfully achieved only from an understanding of the overall functional changes and alterations in physiological parameters under its envenomation. The majority of previous investigations on jellyfish venoms have covered only a couple of parameters at a time. Unlike most other fragmentary jellyfish studies, we employed an integrative toxicological approach, including hemodynamics, clinical chemistry and hematology analyses, using N. nomurai jellyfish venom (NnV) in dogs. After the baseline measurements for mean arterial pressure (MAP), cardiac output (CO) and heart rate (HR), NnV was intravenously administered to the dogs at doses of 0.1 or 0.3mg/kg body weight. The dogs showed significant decreases in MAP (-27.4±3.7 and -48.1±9.9 mmHg), CO (-1.1±0.1 L/min and -1.0±0.2 L/min), and HR (-4.5±0.3 and -9.9±3.1 beats/min) comparing with the respective baseline controls. The onset of systemic hypotension and bradycardia occurred within 1 min of NnV injection and they lasted for 1-35 min, depending on the NnV doses. Interestingly, serum biochemical analyses of envenomed dogs exhibited dramatic increases of alkaline phosphatase (ALP), creatine phosphokinase (CPK), alanine aminotransferase (ALT) and aspartate aminotransferase (AST), indicating its possible target organs. In conclusion, we have demonstrated simultaneously, for the first time, the multiple organ toxicities (cardiotoxic, myotoxic and hepatotoxic) of a scyphozoan jellyfish venom. Based on these results, an integrative toxinological approach using dogs appears to be effective in predicting jellyfish venom toxicities and designing their therapeutic strategies. We expect this method can be applied to other jellyfish venom research as well. PMID:21821138

Kang, Changkeun; Kim, Young Ki; Lee, Hyunkyoung; Cha, Mijin; Sohn, Eun-Tae; Jung, Eun-Sun; Song, Chiyoun; Kim, Minkyung; Lee, Hee Chun; Kim, Jong-Shu; Hwang, Jin-Yong; Yoon, Won Duk; Kim, Euikyung

2011-01-01

218

Rise and fall of jellyfish in the eastern Bering Sea in relation to climate regime shifts Richard D. Brodeur a,*, Mary Beth Decker b  

E-print Network

Rise and fall of jellyfish in the eastern Bering Sea in relation to climate regime shifts Richard D North Pacific Ocean a b s t r a c t A steep increase in jellyfish biomass, primarily Chrysaora examined the relationships between jellyfish biomass and temperature, ice cover, atmospheric variables

219

Environmental Control of Phase Transition and Polyp Survival of a Massive-Outbreaker Jellyfish  

PubMed Central

A number of causes have been proposed to account for the occurrence of gelatinous zooplankton (both jellyfish and ctenophore) blooms. Jellyfish species have a complex life history involving a benthic asexual phase (polyp) and a pelagic sexual phase (medusa). Strong environmental control of jellyfish life cycles is suspected, but not fully understood. This study presents a comprehensive analysis on the physicochemical conditions that control the survival and phase transition of Cotylorhiza tuberculata; a scyphozoan that generates large outbreaks in the Mediterranean Sea. Laboratory experiments indicated that the influence of temperature on strobilation and polyp survival was the critical factor controlling the capacity of this species to proliferate. Early life stages were less sensitive to other factors such as salinity variations or the competitive advantage provided by zooxanthellae in a context of coastal eutrophication. Coherently with laboratory results, the presence/absence of outbreaks of this jellyfish in a particular year seems to be driven by temperature. This is the first time the environmental forcing of the mechanism driving the life cycle of a jellyfish has been disentangled via laboratory experimentation. Projecting this understanding to a field population under climatological variability results in a pattern coherent with in situ records. PMID:21072185

Prieto, Laura; Astorga, Diana; Navarro, Gabriel; Ruiz, Javier

2010-01-01

220

Role of Thyroxine in Space-Developed Jellyfish  

NASA Technical Reports Server (NTRS)

The Aurelia Metamorphosis Test System was previously used to determine the effects of the space environment on the development and behavior of tiny (1-2 mm) jellyfish ephyrae during the SLS-1 and IML-2 missions. Results from the SLS-1 experiment included the discovery that statolith numbers were significantly reduced in Earth-formed ephyrae flown for nine days in space as compared with ground-based controls. In addition, upon return to Earth, six times more ephyrae which had developed in space than those developed on Earth had pulsing abnormalities, indicating that either these animals did not form their neuromuscular structures normally while in space or they were unable to adapt to the Ig environment upon return to Earth. The metamorphosis process, which enables the formation of ephyrae from polyps is influenced by a hormone, Jf-T4 Oellyfish thyroxine) which is synthesized following iodine administration. Two groups of polyps in space, however, formed ephyrae without iodine administration indicating that Jf-T4 synthesis, utilization, or excretion was different in. the ephyrae. Increased synthesis or build-up in the media of the hormone may also be linked to the increased demineralization of statoliths found in space-exposed ephyrae. In previous experiments, we found that externally administered thyroxine causes increased demineralization of statoliths on Earth. Abnormal pulsina in ephyrae following return to Earth during the SLS-1 mission may also be traced to increased Jf-T4 levels. Thyroxine is known to be important to the normal development and function of the nervous system, heart, and skeletal muscles in higher animals. For this third Jellyfish-in-Space experiment, we proposed to quantitate the levels of Jf- T4 and of T4 receptors in space-developed ephyrae and media and to compare these levels with those of animals developing and at Ig in space and on Earth. We expected to be able to determine whether Jf-T4 synthesis and/or secretion is different in space-flownjellyfish than in controls and to determine which cells (nerve, muscle, lithocytes, etc.)may have enhanced Jf-T4 levels. However, NASA deselected this experiment in August, 1997.

Spangenberg, Dorothy B.

1997-01-01

221

Milbemycin oxime (interceptor) treatment of amphipod parasites (Hyperiidae) from several host jellyfish species.  

PubMed

Wild-caught crystal jellyfish (Aequorea victoria) arrived at the John G. Shedd Aquarium infested with hyperiid amphipods (Hyperia medusarum), which were inadvertently introduced into a system containing several jellyfish species. Affected systems were treated with milbemycin oxime (Interceptor tablets for dogs 51-100 lbs, Novartis Animal Health US, Inc., Greensboro, North Carolina 27408, USA), a treatment prescribed for red bug (Tegastes acroporanus) infestation in corals. Two treatments using one 25-mg aliquot of Interceptor per 10 gallons of tank water administered 6-7 days apart were completed. Overall, treatment to eradicate the parasite from the affected systems was successful. Further studies evaluating the tolerance of jellyfish to milbemycin oxime, particularly in small juvenile Eutonina indicans and Aurelia aurita, are warranted. Based on clinical observations, there were more negative effects associated with the treatment in the hydrozoans than in the scyphozoans. PMID:25831592

Boonstra, Jennifer L; Koneval, Maureen E; Clark, James D; Schick, Mark; Smith, Malissa; Stark, Amy L

2015-03-01

222

Numerical simulations of bell contractions of upside down jellyfish using the immersed boundary method  

NASA Astrophysics Data System (ADS)

Pulsatile jet propulsion is one of the simplest forms of locomotion utilized by macroscopic organisms. Jellyfish use contractions of their bells to form vortex rings that facilitate feeding and locomotion. Once they grow to about 2 cm in diameter, the upside-down jellyfish (genus Cassiopea) situates itself on the ocean substratum with its oral arms towards the sun. These organisms primarily utilize zooanthellae for photosynthetic feeding, while also pulsing their bells to generate feeding currents and to move short distances. Preliminary numerical simulations are presented here which model the motion of the jellyfish as they pulse on the ocean floor. The motion of the bell is measured and fit to a mathematical model using video. The bell motion is used as an input in numerical simulations. Ultimately, contraction of muscle fibers which induce bell contractions will be simulated across Reynolds numbers using the immersed boundary method.

Hamlet, Christina; Miller, Laura

2009-11-01

223

Stable hovering of a jellyfish-like flying machine.  

PubMed

Ornithopters, or flapping-wing aircraft, offer an alternative to helicopters in achieving manoeuvrability at small scales, although stabilizing such aerial vehicles remains a key challenge. Here, we present a hovering machine that achieves self-righting flight using flapping wings alone, without relying on additional aerodynamic surfaces and without feedback control. We design, construct and test-fly a prototype that opens and closes four wings, resembling the motions of swimming jellyfish more so than any insect or bird. Measurements of lift show the benefits of wing flexing and the importance of selecting a wing size appropriate to the motor. Furthermore, we use high-speed video and motion tracking to show that the body orientation is stable during ascending, forward and hovering flight modes. Our experimental measurements are used to inform an aerodynamic model of stability that reveals the importance of centre-of-mass location and the coupling of body translation and rotation. These results show the promise of flapping-flight strategies beyond those that directly mimic the wing motions of flying animals. PMID:24430122

Ristroph, Leif; Childress, Stephen

2014-03-01

224

Stable hovering of a jellyfish-like flying machine  

PubMed Central

Ornithopters, or flapping-wing aircraft, offer an alternative to helicopters in achieving manoeuvrability at small scales, although stabilizing such aerial vehicles remains a key challenge. Here, we present a hovering machine that achieves self-righting flight using flapping wings alone, without relying on additional aerodynamic surfaces and without feedback control. We design, construct and test-fly a prototype that opens and closes four wings, resembling the motions of swimming jellyfish more so than any insect or bird. Measurements of lift show the benefits of wing flexing and the importance of selecting a wing size appropriate to the motor. Furthermore, we use high-speed video and motion tracking to show that the body orientation is stable during ascending, forward and hovering flight modes. Our experimental measurements are used to inform an aerodynamic model of stability that reveals the importance of centre-of-mass location and the coupling of body translation and rotation. These results show the promise of flapping-flight strategies beyond those that directly mimic the wing motions of flying animals. PMID:24430122

Ristroph, Leif; Childress, Stephen

2014-01-01

225

Protective Effect of Tetracycline against Dermal Toxicity Induced by Jellyfish Venom  

PubMed Central

Background Previously, we have reported that most, if not all, of the Scyphozoan jellyfish venoms contain multiple components of metalloproteinases, which apparently linked to the venom toxicity. Further, it is also well known that there is a positive correlation between the inflammatory reaction of dermal tissues and their tissue metalloproteinase activity. Based on these, the use of metalloproteinase inhibitors appears to be a promising therapeutic alternative for the treatment of jellyfish envenomation. Methodology and Principal Findings Tetracycline (a metalloproteinase inhibitor) has been examined for its activity to reduce or prevent the dermal toxicity induced by Nemopilema nomurai (Scyphozoa: Rhizostomeae) jellyfish venom (NnV) using in vitro and in vivo models. HaCaT (human keratinocyte) and NIH3T3 (mouse fibroblast) incubated with NnV showed decreases in cell viability, which is associated with the inductions of metalloproteinase-2 and -9. This result suggests that the use of metalloproteinase inhibitors, such as tetracycline, may prevent the jellyfish venom-mediated local tissue damage. In vivo experiments showed that comparing with NnV-alone treatment, tetracycline pre-mixed NnV demonstrated a significantly reduced progression of dermal toxicity upon the inoculation onto rabbit skin. Conclusions/Significance It is believed that there has been no previous report on the therapeutic agent of synthetic chemical origin for the treatment of jellyfish venom-induced dermonecrosis based on understanding its mechanism of action except the use of antivenom treatment. Furthermore, the current study, for the first time, has proposed a novel mechanism-based therapeutic intervention for skin damages caused by jellyfish stings. PMID:23536767

Kang, Changkeun; Jin, Yeung Bae; Kwak, Jeongsoo; Jung, Hongseok; Yoon, Won Duk; Yoon, Tae-Jin; Kim, Jong-Shu; Kim, Euikyung

2013-01-01

226

Biogeography of jellyfish in the North Atlantic, by traditional and genomic methods  

NASA Astrophysics Data System (ADS)

Scientific debate on whether the recent increase in reports of jellyfish outbreaks is related to a true rise in their abundance, have outlined the lack of reliable records of Cnidaria and Ctenophora. Here we describe different data sets produced within the EU program EUROBASIN, which have been assembled with the aim of presenting an up to date overview of the diversity and standing stocks of jellyfish in the North Atlantic region. Using a net adapted to sample gelatinous zooplankton quantitatively, Cnidaria and Ctenophora were collected in the epipelagic layer during spring-summer 2010-2013, in inshore and offshore waters between 59-68° N Lat and 62° W-5° E Long. Jellyfish were also identified and counted in samples opportunistically collected by other sampling equipment in the same region and at two coastal stations in the Bay of Biscay and in the Gulf of Cadiz. Continuous Plankton Recorder (CPR) samples collected in 2009-2012 were re-analysed with the aim of identifying the time and location of Cnidarian blooms across the North Atlantic basin. Overall the data show high variability in jellyfish abundance and diversity, mainly in relation with different water masses and with the bathymetry. Higher densities were generally recorded on the shelves, where populations tend to be more diversified due to the presence of meropelagic medusae. Comparisons of net records from the G.O. Sars transatlantic cruise show that information on jellyfish diversity differs significantly depending on the sampling gear utilised. Indeed, the big trawls mostly collect relatively large scyphozoan and hydrozoan species, while small hydrozoans and early stages of ctenophora are only caught by smaller nets. Based on CPR data from 2009-2012, blooms of Cnidarians occurred in all seasons across the whole North Atlantic basin. Molecular analysis revealed that, in contrast with what was previously hypothesized, the CPR is able to detect blooms of meroplanktonic and holoplanktonic hydrozoans and scyphozoans. Combining different types of data, key jellyfish taxa for the spring-summer period were identified in the northern North Atlantic regions. Key species for the central and southern North Atlantic could be inferred based on Cnidarian blooms identified by the CPR survey, although this should be confirmed further by comparison with quantitative data. The identification by DNA barcoding of 23 jellyfish specimens collected during the EUROBASIN cruises contributes to increasing the still very limited number of jellyfish sequences available on GenBank. All observations presented here can be downloaded from PANGAEA (http://doi.pangaea.de/10.1594/PANGAEA.835732).

Licandro, P.; Blackett, M.; Fischer, A.; Hosia, A.; Kennedy, J.; Kirby, R. R.; Raab, K.; Stern, R.; Tranter, P.

2014-11-01

227

Recurrent dermatitis and dermal hypersensitivity following a jellyfish sting: a case report and review of literature.  

PubMed

Jellyfish envenomation often causes an immediate painful vesiculopapular eruption. Less commonly it can cause a type IV allergic hypersensitivity that manifests with delayed or recurrent cutaneous lesions at the primary site or distant from the primary site. These secondary reactivations may be related to high antijellyfish immunoglobulin levels, intracutaneously sequestered antigen, or cross-reacting venom. Immunomodulators such as pimecrolimus and tacrolimus and topical and intralesional corticosteroid therapy decrease this recurrent dermatitis. We report a case of a 9-year-old girl with a recurrent jellyfish dermatitis lasting more than 1 year after the initial envenomation. The dermatitis finally resolved after treatment with tacrolimus and intralesional triamcinolone acetonide therapy. PMID:24495001

Loredana Asztalos, Manuela; Rubin, Adam I; Elenitsas, Rosalie; Groft MacFarlane, Caroline; Castelo-Soccio, Leslie

2014-01-01

228

A bio-inspired bell kinematics design of a jellyfish robot using ionic polymer metal composites actuators  

NASA Astrophysics Data System (ADS)

This paper presents the re-creation of the bell deformation cycle of the Aequorea victoria jellyfish. It focuses on the design, fabrication, and characterization of the bio-inspired bell kinematics of an IPMC actuated robotic jellyfish. The shape and bell kinematics of this underwater vehicle are based on the Aequorea victoria jellyfish. This medusa is chosen as a model system based on a comparative bell kinematics study that is conducted among different jellyfish species. Aequorea victoria is known by its low swimming frequency, small bell deformation, and high Froude efficiency (95%). Different methods of implementing the actuators underneath the bell with smaller IPMC actuators are investigated to replicate the natural jellyfish's bell deformation. Results demonstrates that proper placement of the IPMC actuators results in bell configuration that more accurately represents the deformation properties of the natural jellyfish. Smaller IPMC actuators are used to achieve the desired deformation and thus the power consumption is reduced by 70% compared to previous generations. A biomimetic jellyfish robot prototype is built, and its ability to swim and produce thrust with smaller IPMC actuators is shown. The robot swam with four actuators swam at an average speed 0.77 mm/s and consumed 0.7 W. When eight actuators were used the average speed increased to 1.5 mm/s with a power consumption of 1.14 W.

Najem, Joseph; Leo, Donald J.

2012-04-01

229

Rapid scavenging of jellyfish carcasses reveals the importance of gelatinous material to deep-sea food webs.  

PubMed

Jellyfish blooms are common in many oceans, and anthropogenic changes appear to have increased their magnitude in some regions. Although mass falls of jellyfish carcasses have been observed recently at the deep seafloor, the dense necrophage aggregations and rapid consumption rates typical for vertebrate carrion have not been documented. This has led to a paradigm of limited energy transfer to higher trophic levels at jelly falls relative to vertebrate organic falls. We show from baited camera deployments in the Norwegian deep sea that dense aggregations of deep-sea scavengers (more than 1000 animals at peak densities) can rapidly form at jellyfish baits and consume entire jellyfish carcasses in 2.5 h. We also show that scavenging rates on jellyfish are not significantly different from fish carrion of similar mass, and reveal that scavenging communities typical for the NE Atlantic bathyal zone, including the Atlantic hagfish, galatheid crabs, decapod shrimp and lyssianasid amphipods, consume both types of carcasses. These rapid jellyfish carrion consumption rates suggest that the contribution of gelatinous material to organic fluxes may be seriously underestimated in some regions, because jelly falls may disappear much more rapidly than previously thought. Our results also demonstrate that the energy contained in gelatinous carrion can be efficiently incorporated into large numbers of deep-sea scavengers and food webs, lessening the expected impacts (e.g. smothering of the seafloor) of enhanced jellyfish production on deep-sea ecosystems and pelagic-benthic coupling. PMID:25320167

Sweetman, Andrew K; Smith, Craig R; Dale, Trine; Jones, Daniel O B

2014-12-01

230

E 2006, by the American Society of Limnology and Oceanography, Inc. Mass deposition of jellyfish in the deep Arabian Sea  

E-print Network

In December 2002, large numbers of dead jellyfish, Crambionella orsini, were observed on the seabed over a wide area of the Arabian Sea off the coast of Oman at depths between 300 m and 3,300 m. Moribund jellyfish were seen tumbling down the continental slope. Large aggregations of dead jellyfish were evident within canyons and on the continental rise. At the deepest stations, patches of rotting, coagulated jellyfish occurred. The patches were several meters in diameter, at least 7-cm thick, and covered about 17 % of the sediment surface. At other locations on the continental rise the seafloor was covered in a thin, almost continuous, layer of jelly ‘‘slime’ ’ a few millimeters thick or was littered with individual jellyfish corpses. Photographic transects were used to estimate the amount of carbon associated with the jelly detritus. The standing stock of carbon (C) varied between 1.5 g C m 22 and 78 g C m 22, the higher figure exceeding the annual downward flux of organic carbon, as measured by sediment traps, by more than an order of magnitude. The episodic nature of jellyfish blooms, which may be modulated by global change phenomena, provides a hitherto unknown mechanism for large-scale spatial and temporal patchiness in deep-sea benthic ecosystems. Sudden population explosions of jellyfish are a feature of many parts of the world’s oceans (Purcell et al. 2001) and

D. S. M. Billett; B. J. Bett; C. L. Jacobs; I. P. Rouse; B. D. Wigham

231

Vortex motion in the ocean: In situ visualization of jellyfish swimming and feeding flows  

E-print Network

Vortex motion in the ocean: In situ visualization of jellyfish swimming and feeding flows John O upstream of the animal to observe the fluid motion induced by the animal as it swims forward. The formation of a vortex ring is observed as the animal contracts its body. A second vortex ring of opposite rotational

Dabiri, John O.

232

Jellyfish vision starts with cAMP signaling mediated by opsin-Gs cascade  

PubMed Central

Light sensing starts with phototransduction in photoreceptor cells. The phototransduction cascade has diverged in different species, such as those mediated by transducin in vertebrate rods and cones, by Gq-type G protein in insect and molluscan rhabdomeric-type visual cells and vertebrate photosensitive retinal ganglion cells, and by Go-type G protein in scallop ciliary-type visual cells. Here, we investigated the phototransduction cascade of a prebilaterian box jellyfish, the most basal animal having eyes containing lens and ciliary-type visual cells similar to vertebrate eyes, to examine the similarity at the molecular level and to obtain an implication of the origin of the vertebrate phototransduction cascade. We showed that the opsin-based pigment functions as a green-sensitive visual pigment and triggers the Gs-type G protein-mediated phototransduction cascade in the ciliary-type visual cells of the box jellyfish lens eyes. We also demonstrated the light-dependent cAMP increase in the jellyfish visual cells and HEK293S cells expressing the jellyfish opsin. The first identified prebilaterian cascade was distinct from known phototransduction cascades but exhibited significant partial similarity with those in vertebrate and molluscan ciliary-type visual cells, because all involved cyclic nucleotide signaling. These similarities imply a monophyletic origin of ciliary phototransduction cascades distributed from prebilaterian to vertebrate. PMID:18832159

Koyanagi, Mitsumasa; Takano, Kosuke; Tsukamoto, Hisao; Ohtsu, Kohzoh; Tokunaga, Fumio; Terakita, Akihisa

2008-01-01

233

Partial purification and characterization of a hemolysin (CAH1) from Hawaiian box jellyfish ( Carybdea alata) venom  

Microsoft Academic Search

We have isolated and characterized a novel hemolytic protein from the venom of the Hawaiian box jellyfish (Carybdea alata). Hemolysis of sheep red blood cells was used to quantitate hemolytic potency of crude venom extracted from isolated nematocysts and venom after fractionation and purification procedures. Hemolytic activity of crude venom was reduced or lost after exposure to the proteolytic enzymes

John J. Chung; Lal A. Ratnapala; Ian M. Cooke; Angel A. Yanagihara

2001-01-01

234

Biologically active polypeptides in the venom of the jellyfish Rhopilema nomadica  

Microsoft Academic Search

A tropical jellyfish, Rhopilema nomadica (Scyphozoa, Rhizostomeae) has recently invaded the eastern Mediterranean. Its painful stings have been the bane of bathers and fishermen from Egypt to Turkey. This paper reports on the presence of haemolytic activity and ?-chymotrypsin-like serine protease activity in the venom of the R. nomadica nematocysts. In addition, the presence of phospholipase A2 activity, which has

Laura Gusmani; Massimo Avian; Bella Galil; Pierluigi Patriarca; Giandomenico Rottini

1997-01-01

235

The jellyfish green fluorescent protein: A new tool for studying ion channel expression and function  

Microsoft Academic Search

Two methods are described for using the jellyfish green fluorescent protein (GFP) as a reporter gene for ion channel expression. GFP fluorescence can be used to identify the transfected cells, and to estimate the relative levels of ion channel expression, in cotransfection experiments. A GFP-NMDAR1 chimera can be constructed that produces a functional, fluorescent receptor subunit. These methods should facilitate

John Marshall; Raymond Molloy; Guy W. J Moss; James R Howe; Thomas E Hughes

1995-01-01

236

Novel Proteinaceous Toxins from the Box Jellyfish (Sea Wasp) Carybdea rastoni  

Microsoft Academic Search

During summer and autumn, the box jellyfish (sea wasp) Carybdea rastoni is one of the most bothersome stinging pests to swimmers and bathers on the Japanese coast. Two labile but potent hemolytic toxins from the tentacles of Carybdea rastoni were isolated in their active forms using newly developed purification methods. The molecular masses of the isolated C. rastoni toxin-A and

Hiroshi Nagai; Kyoko Takuwa; Masahiro Nakao; Emiko Ito; Masami Miyake; Masatoshi Noda; Terumi Nakajima

2000-01-01

237

Flow patterns generated by oblate medusan jellyfish: field measurements and laboratory analyses  

Microsoft Academic Search

Flow patterns generated by medusan swimmers such as jellyfish are known to differ according the morphology of the various animal species. Oblate medusae have been previously observed to generate vortex ring structures during the propulsive cycle. Owing to the inherent physical coupling between locomotor and feeding structures in these animals, the dynamics of vortex ring formation must be robustly tuned

John O. Dabiri; Sean P. Colin; John H. Costello; Morteza Gharib

2005-01-01

238

Passive energy recapture in jellyfish contributes to propulsive advantage over other metazoans  

PubMed Central

Gelatinous zooplankton populations are well known for their ability to take over perturbed ecosystems. The ability of these animals to outcompete and functionally replace fish that exhibit an effective visual predatory mode is counterintuitive because jellyfish are described as inefficient swimmers that must rely on direct contact with prey to feed. We show that jellyfish exhibit a unique mechanism of passive energy recapture, which is exploited to allow them to travel 30% further each swimming cycle, thereby reducing metabolic energy demand by swimming muscles. By accounting for large interspecific differences in net metabolic rates, we demonstrate, contrary to prevailing views, that the jellyfish (Aurelia aurita) is one of the most energetically efficient propulsors on the planet, exhibiting a cost of transport (joules per kilogram per meter) lower than other metazoans. We estimate that reduced metabolic demand by passive energy recapture improves the cost of transport by 48%, allowing jellyfish to achieve the large sizes required for sufficient prey encounters. Pressure calculations, using both computational fluid dynamics and a newly developed method from empirical velocity field measurements, demonstrate that this extra thrust results from positive pressure created by a vortex ring underneath the bell during the refilling phase of swimming. These results demonstrate a physical basis for the ecological success of medusan swimmers despite their simple body plan. Results from this study also have implications for bioinspired design, where low-energy propulsion is required. PMID:24101461

Gemmell, Brad J.; Costello, John H.; Colin, Sean P.; Stewart, Colin J.; Dabiri, John O.; Tafti, Danesh; Priya, Shashank

2013-01-01

239

Cardiovascular effects of Nemopilema nomurai (Scyphozoa: Rhizostomeae) jellyfish venom in rats  

Microsoft Academic Search

Over the past few years, populations of the giant jellyfish Nemopilema nomurai (Scyphozoa: Rhizostomeae) have increased dramatically in the waters of China, Korea, and Japan without any definitive reason. This has resulted in severe damage to fisheries in the areas. During a pilot study, we observed that the venom of N. nomurai produced a functional cardiac depression in mice. However,

Euikyung Kim; Seunghwan Lee; Jong-Shu Kim; Won Duk Yoon; Donghyun Lim; Andrew J. Hart; Wayne C. Hodgson

2006-01-01

240

The zone-refine driven growth of jellyfish-like core-shell nanowires.  

PubMed

Thermal evaporation of a Sn-silica mixture produces core-shell nanowires assembled into jellyfish-like structures. The growth mechanism involves zone-refine driven phase separation at the solid-liquid interface. The materials emit blue and red lights; the luminescence centers are discussed and verified. PMID:20972493

Wu, Jyun-Lin; Kuo, Hsin-Fu; Chen, Ping-Tzu; Chen, Hung-Jen; Lin, Su-Jien; Hsu, Wen-Kuang

2010-12-21

241

Detection of microvasculature alterations by synchrotron radiation in murine with delayed jellyfish envenomation syndrome.  

PubMed

Using the tentacle extract (TE) from the jellyfish Cyanea capillata, we have previously established a delayed jellyfish envenomation syndrome (DJES) model, which is meaningful for clinical interventions against jellyfish stings. However, the mechanism of DJES still remains unclear. Thus, this study aimed to explore its potential mechanism by detecting TE-induced microvasculature alterations in vivo and ex vivo. Using a third-generation synchrotron radiation facility, we, for the first time, directly observed the blood vessel alterations induced by jellyfish venom in vivo and ex vivo. Firstly, microvasculature imaging of whole-body mouse in vivo indicated that the small blood vessel branches in the liver and kidney in the TE-treated group, seemed much thinner than those in the control group. Secondly, 3D imaging of kidney ex vivo showed that the kidneys in the TE-treated group had incomplete vascular trees where distal vessel branches were partly missing and disorderly disturbed. Finally, histopathological analysis found that obvious morphological changes, especially hemorrhagic effects, were also present in the TE-treated kidney. Thus, TE-induced microvasculature changes might be one of the important mechanisms of multiple organ dysfunctions in DJES. In addition, the methods we employed here will probably facilitate further studies on developing effective intervention strategies against DJES. PMID:24508769

Wang, Beilei; Zhang, Bo; Huo, Hua; Wang, Tao; Wang, Qianqian; Wu, Yuanlin; Xiao, Liang; Ren, Yuqi; Zhang, Liming

2014-04-01

242

Inferring distributions of chirodropid box-jellyfishes (Cnidaria: Cubozoa) in geographic and ecological space using ecological niche modeling  

E-print Network

the potential distributions of these species as well. We explored the utility of ENM to investigate potential distributions of chirodropid box-jellyfishes (Cnidaria: Cubozoa), a group of highly toxic invertebrates whose biogeography is poorly understood. We were...

Bentlage, Bastian; Peterson, A. Townsend; Cartwright, Paulyn

2009-05-29

243

Neutralization of toxic effects of different crude jellyfish venoms by an extract of Ipomoea pes-caprae (L.) R. Br.  

PubMed

An extract (IPA) of the plant Ipomoea pes-caprae (L.) R. Br., previously shown to be clinically effective toward dermatitis caused by venomous jellyfishes, was studied as to its ability to neutralize toxic activities of jellyfish venoms. Different venoms exhibited different degrees of activity. When IPA was incubated with active venoms, it inhibited the actions of all jellyfish venoms tested, with IC50 values in the range of 0.3-0.8 mgIPA/mg venom for proteolytic action, and with about 10 times lower IC50 values for the neutralization of haemolytic action. These activities of IPA support the previously reported effectiveness in the treatment of dermatitis caused by jellyfish sting. PMID:1684405

Pongprayoon, U; Bohlin, L; Wasuwat, S

1991-10-01

244

Interactions of cnidarian toxins with the immune system.  

PubMed

Cnidarians comprise four classes of toxic marine animals: Anthozoa, Cubozoa, Scyphozoa and Hydrozoa. They are the largest and probably the oldest phylum of toxic marine animals. Any contact with a cnidarian, especially the box jellyfish (Chironex fleckeri), can be fatal, but most cnidarians do not possess sufficiently strong venomous apparatus to penetrate the human skin, whereas others rarely come into contact with human beings. Only a small, almost negligible percentage of the vast wealth of cnidarian toxins has been studied in detail. Many polypeptide cnidarian toxins are immunogenic, and cross-reactivity between several jellyfish venoms has been reported. Cnidarians also possess components of innate immunity, and some of those components have been preserved in evolution. On the other hand, cnidarian toxins have already been used for the design of immunotoxins to treat cancer, whereas other cnidarian toxins can modulate the immune system in mammals, including man. This review will focus on a short overview of cnidarian toxins, on the innate immunity of cnidarians, and on the mode of action of cnidarian toxins which can modulate the immune system in mammals. Emphasis is palced on those toxins which block voltage activated potassium channels in the cells of the immune system. PMID:21824078

Suput, Dusan

2011-10-01

245

Efficacy of venom from tentacle of jellyfish Stomolophus meleagris (Nemopilema nomurai) against the cotton bollworm Helicoverpa armigera.  

PubMed

Efficacy of venom from tentacle of jellyfish Stomolophus meleagris against the cotton bollworm Helicoverpa armigera was determined. Venom from tentacle of jellyfish Stomolophus meleagris could inhibit the growth of Helicoverpa armigera and the weight inhibiting rate of sample NFr-2 was 60.53%. Of the six samples, only NFr-2 had high insecticidal activity against Helicoverpa armigera and the corrected mortality recorded at 7 d was 74.23%. PMID:25162008

Yu, Huahua; Li, Rongfeng; Dong, Xiangli; Xing, Ronge; Liu, Song; Li, Pengcheng

2014-01-01

246

Ontogenetic changes in the ecological function of the association behavior between jack mackerel Trachurus japonicus and jellyfish  

Microsoft Academic Search

Commensal behavior of jack mackerel Trachurus japonicus (Temminck & Schlegel) with jellyfishes has been widely observed but its ecological function is still unclear. The goal of\\u000a the present research is to examine the function of association behavior with jellyfish in the laboratory and in field observations\\u000a with an emphasis on ontogenetic changes. In the laboratory, jack mackerel juveniles (mean standard

Reiji Masuda

2009-01-01

247

Ontogenetic changes in the ecological function of the association behavior between jack mackerel Trachurus japonicus and jellyfish  

Microsoft Academic Search

Commensal behavior of jack mackerel Trachurus japonicus (Temminck & Schlegel) with jellyfishes has been widely observed but its ecological function is still unclear. The goal of\\u000a the present research is to examine the function of association behavior with jellyfish in the laboratory and in field observations\\u000a with an emphasis on ontogenetic changes. In the laboratory, jack mackerel juveniles (mean standard

Reiji Masuda

248

Efficacy of Venom from Tentacle of Jellyfish Stomolophus meleagris (Nemopilema nomurai) against the Cotton Bollworm Helicoverpa armigera  

PubMed Central

Efficacy of venom from tentacle of jellyfish Stomolophus meleagris against the cotton bollworm Helicoverpa armigera was determined. Venom from tentacle of jellyfish Stomolophus meleagris could inhibit the growth of Helicoverpa armigera and the weight inhibiting rate of sample NFr-2 was 60.53%. Of the six samples, only NFr-2 had high insecticidal activity against Helicoverpa armigera and the corrected mortality recorded at 7?d was 74.23%. PMID:25162008

Yu, Huahua; Li, Rongfeng; Dong, Xiangli; Xing, Ronge; Liu, Song; Li, Pengcheng

2014-01-01

249

Spatiotemporal distribution of protozooplankton and copepod nauplii in relation to the occurrence of giant jellyfish in the Yellow Sea  

NASA Astrophysics Data System (ADS)

The occurrence of the giant jellyfish, Nemopilema nomurai, has been a frequent phenomenon in the Yellow Sea. However, the relationship between the giant jellyfish and protozoa, in particular ciliates, remains largely unknown. We investigated the distribution of nanoflagellates, ciliates, Noctiluca scintillans, and copepod nauplii along the transect 33°N in the Yellow Sea in June and August, 2012, during an occurrence of the giant jellyfish, and in October of that year when the jellyfish was absent. The organisms studied were mainly concentrated in the surface waters in summer, while in autumn they were evenly distributed in the water column. Nanoflagellate, ciliate, and copepod nauplii biomasses increased from early June to August along with jellyfish growth, the first two decreased in October, while N. scintillans biomass peaked in early June to 3 571 ?g C/L and decreased in August and October. In summer, ciliate biomass greatly exceeded that of copepod nauplii (4.61-15.04 ?g C/L vs. 0.34-0.89 ?g C/L). Ciliate production was even more important than biomass, ranging from 6.59 to 34.19 ?g C/(L·d) in summer. Our data suggest a tight and positive association among the nano-, micro-, and meso-zooplankton in the study area. Statistical analysis revealed that the abundance and total production of ciliate as well as loricate ciliate biomass were positively correlated with giant jellyfish biomass, indicating a possible predator-prey relationship between ciliates and giant jellyfish. This is in contrast to a previous study, which reported a significant reduction in ciliate standing crops due to the mass occurrence of N. nomurai in summer. Our study indicates that, with its high biomass and, in particular, high production ciliates might support the mass occurrence of giant jellyfish.

Wang, Lu; Xu, Kuidong

2013-11-01

250

Transportation of organic matter to the sea floor by carrion falls of the giant jellyfish Nemopilema nomurai in the Sea of Japan  

Microsoft Academic Search

The fate of the giant jellyfish Nemopilema nomurai after death was examined in the southwest Sea of Japan. The density of dead jellyfish was greater than that of live animals.\\u000a The dead animals are heavier than the Japan Sea Proper Water which occurs deeper than 200 m, suggesting that dead jellyfish\\u000a sink to the sea floor. The sea floor survey, conducted

Jun Yamamoto; Miyuki Hirose; Tetsuya Ohtani; Katashi Sugimoto; Kazue Hirase; Nobuo Shimamoto; Tsuyoshi Shimura; Natsumi Honda; Yasuzumi Fujimori; Tohru Mukai

2008-01-01

251

Jellyfish prediction of occurrence from remote sensing data and a non-linear pattern recognition approach  

NASA Astrophysics Data System (ADS)

Impact of jellyfish in human activities has been increasingly reported worldwide in recent years. Segments such as tourism, water sports and leisure, fisheries and aquaculture are commonly damaged when facing blooms of gelatinous zooplankton. Hence the prediction of the appearance and disappearance of jellyfish in our coasts, which is not fully understood from its biological point of view, has been approached as a pattern recognition problem in the paper presented herein, where a set of potential ecological cues was selected to test their usefulness for prediction. Remote sensing data was used to describe environmental conditions that could support the occurrence of jellyfish blooms with the aim of capturing physical-biological interactions: forcing, coastal morphology, food availability, and water mass characteristics are some of the variables that seem to exert an effect on jellyfish accumulation on the shoreline, under specific spatial and temporal windows. A data-driven model based on computational intelligence techniques has been designed and implemented to predict jellyfish events on the beach area as a function of environmental conditions. Data from 2009 over the NW Mediterranean continental shelf have been used to train and test this prediction protocol. Standard level 2 products are used from MODIS (NASA OceanColor) and MERIS (ESA - FRS data). The procedure for designing the analysis system can be described as following. The aforementioned satellite data has been used as feature set for the performance evaluation. Ground truth has been extracted from visual observations by human agents on different beach sites along the Catalan area. After collecting the evaluation data set, the performance between different computational intelligence approaches have been compared. The outperforming one in terms of its generalization capability has been selected for prediction recall. Different tests have been conducted in order to assess the prediction capability of the resulting system in operational conditions. This includes taking into account several types of features with different distances in both the spatial and temporal domains with respect to prediction time and site. Moreover the generalization capability has been measured via cross-fold validation. The implementation and performance evaluation results are detailed in the present communication together with the feature extraction from satellite data. To the best of our knowledge the developed application constitutes the first implementation of an automate system for the prediction of jellyfish appearance founded on remote sensing technologies.

Albajes-Eizagirre, Anton; Romero, Laia; Soria-Frisch, Aureli; Vanhellemont, Quinten

2011-11-01

252

Comparative analysis of methods for concentrating venom from jellyfish Rhopilema esculentum Kishinouye  

NASA Astrophysics Data System (ADS)

In this study, several methods were compared for the efficiency to concentrate venom from the tentacles of jellyfish Rhopilema esculentum Kishinouye. The results show that the methods using either freezing-dry or gel absorption to remove water to concentrate venom are not applicable due to the low concentration of the compounds dissolved. Although the recovery efficiency and the total venom obtained using the dialysis dehydration method are high, some proteins can be lost during the concentrating process. Comparing to the lyophilization method, ultrafiltration is a simple way to concentrate the compounds at high percentage but the hemolytic activities of the proteins obtained by ultrafiltration appear to be lower. Our results suggest that overall lyophilization is the best and recommended method to concentrate venom from the tentacles of jellyfish. It shows not only the high recovery efficiency for the venoms but high hemolytic activities as well.

Li, Cuiping; Yu, Huahua; Feng, Jinhua; Chen, Xiaolin; Li, Pengcheng

2009-02-01

253

Reynolds number limits for jet propulsion: A numerical study of simplified jellyfish  

E-print Network

The Scallop Theorem states that reciprocal methods of locomotion, such as jet propulsion or paddling, will not work in Stokes flow (Reynolds number = 0). In nature the effective limit of jet propulsion is still in the range where inertial forces are significant. It appears that almost all animals that use jet propulsion swim at Reynolds numbers (Re) of about 5 or more. Juvenile squid and octopods hatch from the egg already swimming in this inertial regime. The limitations of jet propulsion at intermediate Re is explored here using the immersed boundary method to solve the two-dimensional Navier Stokes equations coupled to the motion of a simplified jellyfish. The contraction and expansion kinematics are prescribed, but the forward and backward swimming motions of the idealized jellyfish are emergent properties determined by the resulting fluid dynamics. Simulations are performed for both an oblate bell shape using a paddling mode of swimming and a prolate bell shape using jet propulsion. Average forward veloc...

Herschlag, Gregory

2010-01-01

254

Faking giants: the evolution of high prey clearance rates in jellyfishes.  

PubMed

Jellyfishes have functionally replaced several overexploited commercial stocks of planktivorous fishes. This is paradoxical, because they use a primitive prey capture mechanism requiring direct contact with the prey, whereas fishes use more efficient visual detection. We have compiled published data to show that, in spite of their primitive life-style, jellyfishes exhibit similar instantaneous prey clearance and respiration rates as their fish competitors and similar potential for growth and reproduction. To achieve this production, they have evolved large, water-laden bodies that increase prey contact rates. Although larger bodies are less efficient for swimming, optimization analysis reveals that large collectors are advantageous if they move through the water sufficiently slowly. PMID:21921197

Acuña, José Luis; López-Urrutia, Ángel; Colin, Sean

2011-09-16

255

Pentaplex PCR as screening assay for jellyfish species identification in food products.  

PubMed

Salted jellyfish, a traditional food in Asian Countries, is nowadays spreading on the Western markets. In this work, we developed a Pentaplex PCR for the identification of five edible species (Nemopilema nomurai, Rhopilema esculentum, Rhizostoma pulmo, Pelagia noctiluca, and Cotylorhiza tuberculata), which cannot be identified by a mere visual inspection in jellyfish products sold as food. A common degenerated forward primer and five specie-specific reverse primers were designed to amplify COI gene regions of different lengths. Another primer pair targeted the 28SrRNA gene and was intended as common positive reaction control. Considering the high level of degradation in the DNA extracted from acidified and salted products, the maximum length of the amplicons was set at 200 bp. The PCR was developed using 66 reference DNA samples. It gave successful amplifications in 85.4% of 48 ready to eat products (REs) and in 60% of 30 classical salted products (CPs) collected on the market. PMID:25393326

Armani, Andrea; Giusti, Alice; Castigliego, Lorenzo; Rossi, Aurelio; Tinacci, Lara; Gianfaldoni, Daniela; Guidi, Alessandra

2014-12-17

256

Transient expression and stable transformation of soybean using the jellyfish green fluorescent protein  

Microsoft Academic Search

Embryogenic soybean [Glycine max (L.) Merrill.] suspension cultures were bombarded with five different gene constructions encoding the jellyfish (Aequorea victoria) green fluorescent protein (GFP). These constructions had altered codon usage compared to the native GFP gene and mutations\\u000a that increased the solubility of the protein and\\/or altered the native chromophore. All of the constructions produced green\\u000a fluorescence in soybean cultures

T. Ponappa; A. E. Brzozowski; J. J. Finer

1999-01-01

257

Purification and properties of a cytolytic toxin in venom of the jellyfish Carybdea marsupialis  

Microsoft Academic Search

A haemolytic toxin was purified by ion-exchange chromatography and FPLC gel filtration from the nematocysts of the jellyfish Carybdea marsupialis. Sheep red cells, but not human or rabbit red cells, were susceptible to lysis by the toxin. The toxin is a protein with an apparent molecular mass of about 102–107 kDa, is heat labile, highly unstable in polar media, inactivated

Giandomenico Rottini; Laura Gusmani; Elisabetta Parovel; Massimo Avian; Pierluigi Patriarca

1995-01-01

258

Evolutionary aspects of developmentally regulated helix-loop-helix transcription factors in striated muscle of jellyfish  

Microsoft Academic Search

The function of basic helix-loop-helix (bHLH) proteins in cell differentiation was shown to be conserved from Drosophila to vertebrates, exemplified by the function of MyoD in striated muscle differentiation. In phylogeny striated muscle tissue appears first in jellyfish and the question of its evolutionary position is controversially discussed. For this reason we have studied the developmental role of myogenic bHLH

Peter Müller; Katja Seipel; Nathalie Yanze; Susanne Reber-Müller; Ruth Streitwolf-Engel; Michael Stierwald; J. ürg Spring; Volker Schmid

2003-01-01

259

Nutrient cycling and the biogeochemistry of manganese, iron. and zinc in Jellyfish Lake, Palau  

Microsoft Academic Search

The oxic waters in Jellyfish Lake, a stagnant marine lake in Palau, are depleted in N03-, POd3-, dissolved Si, Mn, Fe, and Zn, while the underlying anoxic waters are significantly enriched in these species and NH,. NH, and Pod3 regeneration and dissolved sulfide production in the anoxic zone yield a stoichiometry of C,,,N,,P for organic matter undergoing recycling in the

WILLIAM M. LANDING; WILLIAM C. BURNETT; W. BERRY LYONS; WILLIAM H. OREM

1991-01-01

260

Biomimetic jellyfish-inspired underwater vehicle actuated by ionic polymer metal composite actuators  

NASA Astrophysics Data System (ADS)

This paper presents the design, fabrication, and characterization of a biomimetic jellyfish robot that uses ionic polymer metal composites (IPMCs) as flexible actuators for propulsion. The shape and swimming style of this underwater vehicle are based on the Aequorea victoria jellyfish, which has an average swimming speed of 20 mm s-1 and which is known for its high swimming efficiency. The Aequorea victoria is chosen as a model system because both its bell morphology and kinematic properties match the mechanical properties of IPMC actuators. This medusa is characterized by its low swimming frequency, small bell deformation during the contraction phase, and high Froude efficiency. The critical components of the robot include the flexible bell that provides the overall shape and dimensions of the jellyfish, a central hub and a stage used to provide electrical connections and mechanical support to the actuators, eight distinct spars meant to keep the upper part of the bell stationary, and flexible IPMC actuators that extend radially from the central stage. The bell is fabricated from a commercially available heat-shrinkable polymer film to provide increased shape-holding ability and reduced weight. The IPMC actuators constructed for this study demonstrated peak-to-peak strains of ˜0.7% in water across a frequency range of 0.1-1.0 Hz. By tailoring the applied voltage waveform and the flexibility of the bell, the completed robotic jellyfish with four actuators swam at an average speed 0.77 mm s-1 and consumed 0.7 W. When eight actuators were used the average speed increased to 1.5 mm s-1 with a power consumption of 1.14 W.

Najem, Joseph; Sarles, Stephen A.; Akle, Barbar; Leo, Donald J.

2012-09-01

261

Purification, characterization and cDNA cloning of a novel lectin from the jellyfish Nemopilema nomurai  

Microsoft Academic Search

A lectin (designated NnL) from a jellyfish Nemopilema nomurai was purified by ion-exchange chromatography followed by affinity chromatography. The apparent molecular mass of NnL was 28kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis under reducing and nonreducing conditions. NnL agglutinated horse erythrocytes, the gram-positive bacterium Bacillus subtilis and gram-negative bacterium Escherichia coli K12. The hemagglutinating activity of NnL was inhibited by

Yoshitaka Imamichi; Yoshihiro Yokoyama

2010-01-01

262

Seasonal changes in oocyte size and maturity of the giant jellyfish, Nemopilema nomurai  

Microsoft Academic Search

To determine the reproductive season of the giant jellyfish Nemopilema nomurai, we investigated gonadal maturity in specimens collected from the East China Sea, Korea Strait, Wakasa Bay, and the Shonai\\u000a Coast of Yamagata Prefecture. After the sex of the samples was determined, the long axis of at least 256 oocytes from each\\u000a female was measured. In specimens collected from the

Masaya Toyokawa; Akio Shimizu; Katashi Sugimoto; Kou Nishiuchi; Toru Yasuda

2010-01-01

263

Experimental induction of gonadal maturation and spawning in the giant jellyfish Nemopilema nomurai (Scyphozoa: Rhizostomeae)  

Microsoft Academic Search

We studied the processes of gonadal maturation, spawning, fertilization and embryonic development of the giant jellyfish Nemopilema nomurai, which has been blooming in recent years in the Sea of Japan. Healthy medusae actively swimming offshore had immature gonads,\\u000a but damaged and ashore-drifted animals had relatively mature gonads. The animals maintained in a small net on the nearshore\\u000a to mimic the

Kohzoh Ohtsu; Masato Kawahara; Hideki Ikeda; Shin-ichi Uye

2007-01-01

264

A new cyclic tetrapeptide from the jellyfish-derived fungus Phoma sp.  

PubMed

A new cyclic tetrapeptide (1), along with known congeners (2, 3), was isolated from the fungus Phoma sp. derived from the giant jellyfish Nemopilema nomurai. The absolute configuration of 1 was determined using the modified Mosher's method and Marfey's method. Compound 1 displayed a weak suppressive effect on the production of nitric oxide (NO) in murine macrophage cells (RAW264.7) without notable cytotoxicity. PMID:23037010

Kim, Eun La; Li, Jian Lin; Xiao, Bin; Hong, Jongki; Yoo, Eun Sook; Yoon, Won Duk; Jung, Jee H

2012-01-01

265

Current Biology 24, 111, February 3, 2014 2014 Elsevier Ltd All rights reserved http://dx.doi.org/10.1016/j.cub.2013.12.003 Regulation of Polyp-to-Jellyfish  

E-print Network

://dx.doi.org/10.1016/j.cub.2013.12.003 Article Regulation of Polyp-to-Jellyfish Transition in Aurelia aurita Bjo machinery controlling transition of the sessile polyp into a free-swimming jellyfish consists of two parts of the strobilation hormone of Aurelia. Conclusions: Our findings uncover the molecule framework controlling the polyp-to-jellyfish

266

Jellyfish mucin may have potential disease-modifying effects on osteoarthritis  

PubMed Central

Background We aimed to study the effects of intra-articular injection of jellyfish mucin (qniumucin) on articular cartilage degeneration in a model of osteoarthritis (OA) created in rabbit knees by resection of the anterior cruciate ligament. Qniumucin was extracted from Aurelia aurita (moon jellyfish) and Stomolophus nomurai (Nomura's jellyfish) and purified by ion exchange chromatography. The OA model used 36 knees in 18 Japanese white rabbits. Purified qniumucin extracts from S. nomurai or A. aurita were used at 1 mg/ml. Rabbits were divided into four groups: a control (C) group injected with saline; a hyaluronic acid (HA)-only group (H group); two qniumucin-only groups (M groups); and two qniumucin + HA groups (MH groups). One milligram of each solution was injected intra-articularly once a week for 5 consecutive weeks, starting from 4 weeks after surgery. Ten weeks after surgery, the articular cartilage was evaluated macroscopically and histologically. Results In the C and M groups, macroscopic cartilage defects extended to the subchondral bone medially and laterally. When the H and both MH groups were compared, only minor cartilage degeneration was observed in groups treated with qniumucin in contrast to the group without qniumucin. Histologically, densely safranin-O-stained cartilage layers were observed in the H and two MH groups, but cartilage was strongly maintained in both MH groups. Conclusion At the concentrations of qniumucin used in this study, injection together with HA inhibited articular cartilage degeneration in this model of OA. PMID:19995451

2009-01-01

267

Optimization of antioxidant activity by response surface methodology in hydrolysates of jellyfish (Rhopilema esculentum) umbrella collagen*  

PubMed Central

To optimize the hydrolysis conditions to prepare hydrolysates of jellyfish umbrella collagen with the highest hydroxyl radical scavenging activity, collagen extracted from jellyfish umbrella was hydrolyzed with trypsin, and response surface methodology (RSM) was applied. The optimum conditions obtained from experiments were pH 7.75, temperature (T) 48.77 °C, and enzyme-to-substrate ratio ([E]/[S]) 3.50%. The analysis of variance in RSM showed that pH and [E]/[S] were important factors that significantly affected the process (P<0.05 and P<0.01, respectively). The hydrolysates of jellyfish umbrella collagen were fractionated by high performance liquid chromatography (HPLC), and three fractions (HF-1>3000 Da, 1000 Da

Zhuang, Yong-liang; Zhao, Xue; Li, Ba-fang

2009-01-01

268

A GLIMPSE of the Southern Jellyfish Nebula and Its Massive YSO  

NASA Astrophysics Data System (ADS)

In Spitzer/IRAC images obtained under the GLIMPSE Legacy Survey, we have identified a unique and provocative nebular object we call the ``Southern Jellyfish Nebula.'' The Southern Jellyfish Nebula is characterized by a fan of narrow tendrils with extreme length-to-width ratios that emanate from the vicinity of a bright infrared point source embedded in a smaller resolved nebula. From CO observations of the Nebula's morphologically associated molecular cloud, we have derived a kinematic distance of 5.7+/-0.8 kpc and a cloud mass of 3.2+/-0.9×103 Msolar. The tendril-like ropes of the Nebula have widths of ~0.1 pc and lengths of up to ~2 pc. We have integrated the infrared spectral energy distribution (SED) of the point source to establish it as a massive young stellar object (MYSO), most likely forming alone, but possibly masking fainter cluster members. The shape of the SED is consistent with the shape of a late Class 0 SED model. Based on its far-IR luminosity of 3.3+/-0.9×104 Lsolar, the Southern Jellyfish's MYSO has a zero-age main sequence (ZAMS) spectral type of B0. Given the curious nature of this nebula, we suspect its peculiar IR-bright structure is directly related to its current state of star formation.

Mercer, E. P.; Clemens, D. P.; Rathborne, J. M.; Meade, M. R.; Babler, B. L.; Indebetouw, R.; Whitney, B. A.; Watson, C.; Wolfire, M. G.; Wolff, M. J.; Bania, T. M.; Benjamin, R. A.; Cohen, M.; Dickey, J. M.; Jackson, J. M.; Kobulnicky, H. A.; Mathis, J. S.; Stolovy, S. R.; Uzpen, B.; Churchwell, E. B.

2007-02-01

269

Neuropeptides trigger oocyte maturation and subsequent spawning in the hydrozoan jellyfish Cytaeis uchidae.  

PubMed

Oocyte maturation and subsequent spawning in hydrozoan jellyfish are generally triggered by light-dark cycles. To examine if the initiation of the maturation process after light stimulus is mediated by neurotransmitters, neuropeptides isolated originally from Hydra magnipapillata were applied to sexually mature female medusae of the hydrozoan jellyfish Cytaeis uchidae. Among the Hydra neuropeptides tested, Hym-53 (NPYPGLW-NH2 ), as well as a nonphysiological peptide, CGLWamide (CGLW-NH2 ), were most effective in inducing oocyte maturation and spawning. Hym-355 (FPQSFLPRG-NH2 ) also triggered these events, but the stimulatory effect was weaker. Since Hym-53-OH (NPYPGLW) and Hym-355-OH (FPQSFLPRG) had no effect, amidation at the C-terminus may be critical for the stimulatory activities of the peptides. Exposure to Hym-53 for 2 min was sufficient to trigger of oocyte maturation, and the spawned eggs were able to be fertilized and to develop normally. Transmission electron microscopy confirmed that bundles of axon-like structures that contain dense-core synaptic vesicles and microtubules are present in the ovarian ectodermal epithelium overlying the oocytes. In addition, immunohistological analyses revealed that some of the neurons in the ectodermal epithelium are GLWamide- and PRGamide-positive. These results suggest that a neuropeptide signal transduction pathway is involved in mediating the induction of oocyte maturation and spawning in this jellyfish. PMID:23341254

Takeda, Noriyo; Nakajima, Yoko; Koizumi, Osamu; Fujisawa, Toshitaka; Takahashi, Toshio; Matsumoto, Midori; Deguchi, Ryusaku

2013-03-01

270

Isolation, Characterization and Biological Evaluation of Jellyfish Collagen for Use in Biomedical Applications  

E-print Network

Abstract: Fibrillar collagens are the more abundant extracellular proteins. They form a metazoan-specific family, and are highly conserved from sponge to human. Their structural and physiological properties have been successfully used in the food, cosmetic, and pharmaceutical industries. On the other hand, the increase of jellyfish has led us to consider this marine animal as a natural product for food and medicine. Here, we have tested different Mediterranean jellyfish species in order to investigate the economic potential of their collagens. We have studied different methods of collagen purification (tissues and experimental procedures). The best collagen yield was obtained using Rhizostoma pulmo oral arms and the pepsin extraction method (2–10 mg collagen/g of wet tissue). Although a significant yield was obtained with Cotylorhiza tuberculata (0.45 mg/g), R. pulmo was used for further experiments, this jellyfish being considered as harmless to humans and being an abundant source of material. Then, we compared the biological properties of R. pulmo collagen with mammalian fibrillar collagens in cell cytotoxicity assays and cell adhesion. There was no statistical difference in cytotoxicity (p> 0.05) between R. pulmo collagen and rat type I collagen. However, since heparin

Sourour Addad; Jean-yves Exposito; Clément Faye; Sylvie Ricard-blum; Claire Lethias

2011-01-01

271

Optimization of antioxidant activity by response surface methodology in hydrolysates of jellyfish (Rhopilema esculentum) umbrella collagen.  

PubMed

To optimize the hydrolysis conditions to prepare hydrolysates of jellyfish umbrella collagen with the highest hydroxyl radical scavenging activity, collagen extracted from jellyfish umbrella was hydrolyzed with trypsin, and response surface methodology (RSM) was applied. The optimum conditions obtained from experiments were pH 7.75, temperature (T) 48.77 degrees C, and enzyme-to-substrate ratio ([E]/[S]) 3.50%. The analysis of variance in RSM showed that pH and [E]/[S] were important factors that significantly affected the process (P<0.05 and P<0.01, respectively). The hydrolysates of jellyfish umbrella collagen were fractionated by high performance liquid chromatography (HPLC), and three fractions (HF-1>3000 Da, 1000 Da

Zhuang, Yong-liang; Zhao, Xue; Li, Ba-fang

2009-08-01

272

Lessons learned from the jellyfish: Fluid transport at intermediate Reynolds numbers  

NASA Astrophysics Data System (ADS)

Biologically inspired hydrodynamic propulsion and maneuvering strategies promise the advancement of medical implants and novel robotic tools. We have chosen juvenile jellyfish as a model system for investigating fluid dynamics and morphological properties underlying fluid transport by an elastic system at intermediate Reynolds numbers. Recently we have described how natural variations in viscous forces are balanced by changes in jellyfish body shape (phenotypic plasticity), to the effect of facilitating efficient body-fluid interaction. Complementing these studies in our live model organisms, we are also engaged in engineering a synthetic jellyfish, that is, a rhythmically actuated elastomer capable of generating efficient feeding and propulsion currents. The main challenges here are (1) to derive a body shape and deformation suitable for effective fluid transport under physiological fluid conditions, (2) to understand the mechanical properties of actuator and elastomer to derive a design capable of the desired deformation, (3) to establish adequate 3D kinematics of power and recovery stroke, and (4) to evaluate the performance of the design.

Nawroth, Janna; Dabiri, John

2011-11-01

273

[Effects of macro-jellyfish abundance dynamics on fishery resource structure in the Yangtze River estuary and its adjacent waters].  

PubMed

Based on the bottom trawl survey data in May 2007 and May and June 2008, this paper analyzed the effects of the abundance dynamics of macro-jellyfish on the species composition, distribution, and abundance of fishery resource in the Yangtze River estuary and its adjacent waters. From May 2007 to June 2008, the average catch per haul and the top catch per haul of macro-jellyfish increased, up to 222.2 kg x h(-1) and 1800 kg x h(-1) in June 2008, respectively. The macro-jellyfish were mainly distributed in the areas around 50 m isobath, and not beyond 100 m isobath where was the joint front of the coastal waters of East China Sea, Yangtze River runoff, and Taiwan Warm Current. The main distribution area of macro-jellyfish in June migrated northward, as compared with that in May, and the highest catches of macro-jellyfish in May 2007 and May 2008 were found in the same sampling station (122.5 degrees E, 28.5 degrees N). In the sampling stations with higher abundance of macro-jellyfish, the fishery abundance was low, and the fishery species also changed greatly, mainly composed by small-sized species (Trachurus japonicus, Harpadon nehereus, and Acropoma japonicum) and pelagic species (Psenopsis anomala, Octopus variabilis) and Trichiurus japonicus, and P. anomala accounted for 23.7% of the total catch in June 2008. Larimichthys polyactis also occupied higher proportion of the total catch in sampling stations with higher macro-jellyfish abundance, but the demersal species Lophius litulon was not found, and a few crustaceans were collected. This study showed that macro-jellyfish had definite negative effects on the fishery community structure and abundance in the Yangtze River estuary fishery ecosystem, and further, changed the energy flow patterns of the ecosystem through cascading trophic interactions. Therefore, macro-jellyfish was strongly suggested to be an independent ecological group when the corresponding fishery management measures were considered. PMID:22384604

Shan, Xiu-Juan; Zhuang, Zhi-Meng; Jin, Xian-Shi; Dai, Fang-Qun

2011-12-01

274

Jellyfish as Prey: Frequency of Predation and Selective Foraging of Boops boops (Vertebrata, Actinopterygii) on the Mauve Stinger Pelagia noctiluca (Cnidaria, Scyphozoa)  

PubMed Central

In recent years, jellyfish blooms have attracted considerable scientific interest for their potential impacts on human activities and ecosystem functioning, with much attention paid to jellyfish as predators and to gelatinous biomass as a carbon sink. Other than qualitative data and observations, few studies have quantified direct predation of fish on jellyfish to clarify whether they may represent a seasonally abundant food source. Here we estimate predation frequency by the commercially valuable Mediterranean bogue, Boops boops on the mauve stinger jellyfish, Pelagia noctiluca, in the Strait of Messina (NE Sicily). A total of 1054 jellyfish were sampled throughout one year to quantify predation by B. boops from bite marks on partially eaten jellyfish and energy density of the jellyfish. Predation by B. boops in summer was almost twice that in winter, and they selectively fed according to medusa gender and body part. Calorimetric analysis and biochemical composition showed that female jellyfish gonads had significantly higher energy content than male gonads due to more lipids and that gonads had six-fold higher energy content than the somatic tissues due to higher lipid and protein concentrations. Energetically, jellyfish gonads represent a highly rewarding food source, largely available to B. boops throughout spring and summer. During the remainder of the year, when gonads were not very evident, fish predation switched towards less-selective foraging on the somatic gelatinous biomass. P. noctiluca, the most abundant jellyfish species in the Mediterranean Sea and a key planktonic predator, may represent not only a nuisance for human leisure activities and a source of mortality for fish eggs and larvae, but also an important resource for fish species of commercial value, such as B. boops. PMID:24727977

Fuentes, Veronica L.; Boero, Ferdinando; Guglielmo, Letterio; Purcell, Jennifer E.; Piraino, Stefano

2014-01-01

275

Jellyfish life histories: role of polyps in forming and maintaining scyphomedusa populations.  

PubMed

Large population fluctuations of jellyfish occur over a variety of temporal scales, from weekly to seasonal, inter-annual and even decadal, with some regions of the world reported to be experiencing persistent seasonal bloom events. Recent jellyfish research has focussed on understanding the causes and consequences of these population changes, with the vast majority of studies considering the effect of changing environmental variables only on the pelagic medusa. But many of the bloom-forming species are members of the Scyphozoa with complex metagenic life cycles consisting of a sexually reproducing pelagic medusa and asexually reproducing benthic polyp. Recruitment success during the juvenile (planula, polyp and ephyrae) stages of the life cycle can have a major effect on the abundance of the adult (medusa) population, but until very recently, little was known about the ecology of the polyp or scyphistoma phase of the scyphozoan life cycle. The aim of this review is to synthesise the current state of knowledge of polyp ecology by examining (1) the recruitment and metamorphosis of planulae larvae into polyps, (2) survival and longevity of polyps, (3) expansion of polyp populations via asexual propagation and (4) strobilation and recruitment of ephyrae (juvenile medusae). Where possible, comparisons are made with the life histories of other bentho-pelagic marine invertebrates so that further inferences can be made. Differences between tropical and temperate species are highlighted and related to climate change, and populations of the same species (in particular Aurelia aurita) inhabiting different habitats within its geographic range are compared. The roles that polyps play in ensuring the long-term survival of jellyfish populations as well as in the formation of bloom populations are considered, and recommendations for future research are presented. PMID:22877612

Lucas, Cathy H; Graham, William M; Widmer, Chad

2012-01-01

276

Speciation and isotopic composition of sulfur in sediments from Jellyfish Lake, Palau  

USGS Publications Warehouse

Jellyfish Lake, Palau, is a meromictic marine lake with high organic productivity, low reactive Fe content, and anoxic bottom waters. Sediment samples from Jellyfish Lake were examined for the distribution of sulfur species and their isotopic signatures in order to gain a better understanding of sedimentary sulfur incorporation in Fe-poor environments. Surface samples were taken along a transect from a near-shore site to the center of the lake, and include a sample below oxic water, a sample below the chemocline layer, and samples below anoxic waters. Three additional samples were taken from a core, 2 m long, collected near the lake center. Sulfur to organic carbon weight ratios in all samples were lower than the expected value of 0.36 for normal marine sediment, probably because the lake water is deficient in reactive Fe to form iron sulfides. Total sulfur contents in the surface sediments indicated no changes with distance from shore; however, the sulfur content of the surface sample at the chemocline layer may be slightly higher. Total sulfur content increased with depth in the core and is inversely related to organic carbon content. Organic sulfur is the major sulfur species in the samples, followed in descending order by sulfate, disulfides and monosulfides. Sulfate sulfur isotope ??34S-values are positive (from +20.56 to +12.04???), reflecting the marine source of sulfate in Jellyfish Lake. Disulfide and monosulfide ??34S-values are negative (from -25.07 to -7.60???), because of fractionation during bacterial reduction of sulfate. Monosulfide ??34S-values are somewhat higher than those of disulfides, and they are close to the ??34S-values of organic sulfur. These results indicate that most of the organic sulfur is formed by reaction of bacteriogenic monosulfides, or possibly monosulfide-derived polysulfides, with organic matter in the sediment. ?? 1993.

Bates, A.L.; Spiker, E. C.; Orem, W.H.; Burnett, W.C.

1993-01-01

277

Development studies of Aurelia (Jellyfish) ephyrae which developed during the SLS-1 mission  

NASA Astrophysics Data System (ADS)

Aurelia polyps (scyphistomae) and ephyrae were exposed to microgravity for nine days aboard the space shuttle during the SLS-1 mission. During strobilation, polyps segment transversely and each segment develops into an ephyra. Polyps were induced to strobilate at 28°C, using iodine or thyroxine, at L(Launch)-48h, L-24h, and L+8h. Ephyrae developed in the groups tested in space and on Earth. The number of ephyrae formed per polyp was slightly higher in the L+8h groups as compared with those induced at L-24h and L-48h. On Earth, iodine is used by jellyfish to synthesize jellyfish-thyroxine (JfT 4), needed for ephyra production. Since iodine-treated polyps strobilated and formed ephyrae in space, it appears that jellyfish can synthesize Jf-T4 in space. Indeed, two groups of polyps not given inducer formed ephryae in space, presumably due to enhanced Jf-T4 synthesis, utilization or accumulation. Some ephyrae that formed in space were also fixed in space on Mission Day (MD) 8; others were fixed post-flight. Examination of living ephyrae with the light microscope and fixed ones with the Scanning and Transmission Electron Microscopes revealed that those which developed in space were morphologically very similar to those which developed on Earth. Quantitation of arm numbers determined that there were no significant differences between space and Earth-developed ephyrae. Pulsing abnormalities, however, were found in greater numbers (18.3%) in space-developed ephyrae than in Earth-developed controls (2.9%). These abnormalities suggest abnormal development of the graviceptors, the neuromuscular system, or a defect in the integration between these systems in apparently microgravity-sensitive animals.

Spangenberg, D. B.; Jernigan, T.; McCombs, R.; Lowe, B. T.; Sampson, M.; Slusser, J.

1994-08-01

278

Development studies of Aurelia (jellyfish) ephyrae which developed during the SLS-1 mission  

NASA Technical Reports Server (NTRS)

Aurelia polyps (scyphistomae) and ephyrae were exposed to microgravity for nine days aboard the space shuttle during the SLS-1 mission. During strobilation, polyps segment transversely and each segment develops into an ephyra. Polyps were induced to strobilate at 28 C, using iodine or thyroxine, at L(Launch)-48h, L-24h, and L+8h. Ephyrae developed in the groups tested in space and on Earth. The number of ephyrae formed per polyp was slightly higher in the L+8h groups as compared with those induced at L-24h and L-48h. On Earth, iodine is used by jellyfish to synthesize jellyfish-thyroxine (Jf T(sub 4)), needed for ephyra production. Since iodine-treated polyps strobilated and formed ephyrae in space, it appears that jellyfish can synthesize Jf-T(sub 4) in space. Indeed, two groups of polyps not given inducer formed ephryae in space, presumably due to enhanced Jf-T(sub 4) synthesis, utilization or accumulation. Some ephyrae that formed in space were also fixed in space on Mission Day (MD) 8; others were fixed post-flight. Examination of living ephyrae with the light microscope and fixed ones with the Scanning and Transmission Electron Microscopes revealed that those which developed in space were morphologically very similar to those which developed on Earth. Quantitation of arm numbers determined that there were no significant differences between space and Earth-developed ephyrae. Pulsing abnormalities, however, were found in greater number (18.3%) in space-developed ephyrae than in Earth-developed controls (2.9%). These abnormalities suggest abnormal development of the graviceptors, the neuromuscular system, or a defect in the integration between these systems in apparently microgravity-sensitive animals.

Spangenberg, D. B.; Jernigan, T.; Mccombs, R.; Lowe, B. T.; Sampson, M.; Slusser, J.

1994-01-01

279

Ecosystem relevance of variable jellyfish biomass in the Irish Sea between years, regions and water types  

NASA Astrophysics Data System (ADS)

Monitoring the abundance and distribution of taxa is essential to assess their contribution to ecosystem processes. For marine taxa that are difficult to study or have long been perceived of little ecological importance, quantitative information is often lacking. This is the case for jellyfish (medusae and other gelatinous plankton). In the present work, 4 years of scyphomedusae by-catch data from the 2007-2010 Irish Sea juvenile gadoid fish survey were analysed with three main objectives: (1) to provide quantitative and spatially-explicit species-specific biomass data, for a region known to have an increasing trend in jellyfish abundance; (2) to investigate whether year-to-year changes in catch-biomass are due to changes in the numbers or in the size of medusa (assessed as the mean mass per individual), and (3) to determine whether inter-annual variation patterns are consistent between species and water masses. Scyphomedusae were present in 97% of samples (N = 306). Their overall annual median catch-biomass ranged from 0.19 to 0.92 g m-3 (or 8.6 to 42.4 g m-2). Aurelia aurita and Cyanea spp. (Cyanea lamarckii and Cyanea capillata) made up 77.7% and 21.5% of the total catch-biomass respectively, but species contributions varied greatly between sub-regions and years. No consistent pattern was detected between the distribution and inter-annual variations of the two genera, and contrasting inter-annual patterns emerged when considering abundance either as biomass or as density. Significantly, A. aurita medusae were heavier in stratified than in mixed waters, which we hypothesize may be linked to differences in timing and yield of primary and secondary productions between water masses. These results show the vulnerability of time-series from bycatch datasets to phenological changes and highlight the importance of taking species- and population-specific distribution patterns into account when integrating jellyfish into ecosystem models.

Bastian, Thomas; Lilley, Martin K. S.; Beggs, Steven E.; Hays, Graeme C.; Doyle, Thomas K.

2014-08-01

280

The ontogenetic scaling of hydrodynamics and swimming performance in jellyfish (Aurelia aurita).  

PubMed

It is not well understood how ontogenetic changes in the motion and morphology of aquatic animals influence the performance of swimming. The goals of the present study were to understand how changes in size, shape and behavior affect the hydrodynamics of jet propulsion in the jellyfish Aurelia aurita and to explore how such changes affect the ontogenetic scaling of swimming speed and cost of transport. We measured the kinematics of jellyfish swimming from video recordings and simulated the hydrodynamics of swimming with two computational models that calculated thrust generation by paddle and jet mechanisms. Our results suggest that thrust is generated primarily by jetting and that there is negligible thrust generation by paddling. We examined how fluid forces scaled with body mass using the jet model. Despite an ontogenetic increase in the range of motion by the bell diameter and a decrease in the height-to-diameter ratio, we found that thrust and acceleration reaction scaled with body mass as predicted by kinematic similarity. However, jellyfish decreased their pulse frequency with growth, and speed consequently scaled at a lower exponential rate than predicted by kinematic similarity. Model simulations suggest that the allometric growth in Aurelia results in swimming that is slower, but more energetically economical, than isometric growth with a prolate bell shape. The decrease in pulse frequency over ontogeny allows large Aurelia medusae to avoid a high cost of transport but generates slower swimming than if they maintained a high pulse frequency. Our findings suggest that ontogenetic change in the height-to-diameter ratio and pulse frequency of Aurelia results in swimming that is relatively moderate in speed but is energetically economical. PMID:14555752

McHenry, Matthew J; Jed, Jason

2003-11-01

281

Studies on the hemolytic activity of tentacle extracts of jellyfish Rhopilema esculentum Kishinouye: application of orthogonal test.  

PubMed

The present work is first reporting the hemolytic activity of venom from jellyfish Rhopilema esculentum Kishinouye extracted by different phosphate buffer solutions and incubated at different temperature according to the orthogonal test L6(1) x 3(6). Of the seven controllable independent variables, incubated temperature and phenylmethylsulfonyl fluoride (PMSF) had strongest effect on the hemolytic activity. PMID:16890282

Yu, Huahua; Xing, Ronge; Liu, Song; Li, Cuiping; Guo, Zhanyong; Li, Pengcheng

2007-02-20

282

In vivo transfection of testicular germ cells and transgenesis by using the mitochondrially localized jellyfish fluorescent protein gene  

Microsoft Academic Search

We aimed to introduce foreign DNA into spermatogenic cells in the testis by injection of the DNA encoding jellyfish fluorescent proteins, green fluorescent protein (GFP) and yellow fluorescent protein (YFP) into the seminiferous tubules and in vivo electroporation. We obtained fluorescent spermatozoa only when using the gene of the YFP protein fused to a mitochondrial localization signal peptide. Intracytoplasmic injection

Zhenyong Huang; Masaru Tamura; Takayuki Sakurai; Shinichiro Chuma; Tetsuichiro Saito; Norio Nakatsuji

2000-01-01

283

Presence of trans -6-Hexadecenoic acid in the White Jellyfish Aurelia aurita Lamarck and in a Caribbean gorgonian  

Microsoft Academic Search

An unusual fatty acid,trans-6-hexadecenoic, previously found in the lipids of marine turtles, the ocean sunfish and a sea anemone, is also present in\\u000a the lipids of the white jellyfish and in a common Caribbean sublittoral gorgonian.

S. N. Hooper; R. G. Ackman

1972-01-01

284

The Homeobox Gene Otx of the Jellyfish Podocoryne carnea: Role of a Head Gene in Striated Muscle and Evolution  

Microsoft Academic Search

In many bilaterian animals members of the Otx gene family are expressed in head or brain structures. Cnidarians, however, have no clearly homologous head and no distinct brain; but an Otx homolog from the jellyfish Podocoryne carnea is highly conserved in sequence and domain structure. Sequence similarities extend well beyond the homeodomain and Podocoryne Otx can be aligned over its

Peter Müller; Nathalie Yanze; Volker Schmid; Jürg Spring

1999-01-01

285

THE PARAMETERS AND PROPERTIES OF A GROUP OF ELECTRICALLY COUPLED NEURONES IN THE CENTRAL NERVOUS SYSTEM OF A HYDROZOAN JELLYFISH  

Microsoft Academic Search

SUMMARY 1. Swimming of the jellyfish Polyorchis penicillatus is controlled by a network of large, electrically coupled, motor neurones in the inner nerve- ring (Fig. 3). Recordings from pairs of neurones, even at widely separated positions, display essentially the same electrical activity (Fig. 1). 2. Electrical coupling between neurones is via gap-junctions and is very strong, giving the network a

A. N. SPENCER

286

Conservation of Brachyury, Mef2, and Snail in the Myogenic Lineage of Jellyfish: A Connection to the Mesoderm of Bilateria  

Microsoft Academic Search

One major difference between simple metazoans such as cnidarians and all the bilaterian animals is thought to involve the invention of mesoderm. The terms diploblasts and triploblasts are therefore, often used to group prebilaterian and bilaterian animals, respectively. However, jellyfish contain well developed striated and smooth muscle tissues that derive from the entocodon, a mesoderm-like tissue formed during medusa development.

Jürg Spring; Nathalie Yanze; Christoph Jösch; Arnoud M. Middel; Brigitte Winninger; Volker Schmid

2002-01-01

287

Bioluminescence resonance energy transfer from aequorin to a fluorophore: an artificial jellyfish for applications in multianalyte detection  

Microsoft Academic Search

In nature, the green light emission observed in the jellyfish Aequorea victoria is a result of a non-radiative energy transfer from the excited-state aequorin to the green fluorescent protein. In this work, we have modified the photoprotein aequorin by attaching selected fluorophores at a unique site on the protein. This will allow for in vitro transfer of bioluminescent energy from

Sapna K. Deo; Mara Mirasoli; Sylvia Daunert

2005-01-01

288

A report on a Moon Jellyfish Aurelia aurita bloom in Sishili Bay, Northern Yellow Sea of China in 2009  

Microsoft Academic Search

In recent years, an increasing number of reports on blooms of Moon Jellyfish (Aurelia aurita) have occurred in the northern coast of China. Throughout the summer of 2009, we studied the occurrence of an A. aurita bloom in relation to environmental variables in the Yantai Sishili Bay of the Northern Yellow Sea. The mean abundance of A. aurita was 0.62

Zhijun Dong; Dongyan Liu; Yujue Wang; Baoping Di; Xiukai Song; Yajun Shi

2012-01-01

289

Original Article DOI: 10.4176/081215 Skin and Systemic Manifestations of Jellyfish Stings in Iraqi Fishermen  

E-print Network

Background: Jellyfish stings are common worldwide with an estimated 150 million cases annually, and their stings cause a wide range of clinical manifestations from skin inflammation to cardiovascular and respiratory collapse. No studies on jellyfish stings have been carried out in Basra, Iraq. Objectives: To describe the immediate and delayed skin reactions to White Jellyfish (Rhizostoma sp.) stings and the types of local treatment used by fishermen. Methods and Materials: 150 fishermen were enrolled at three Marine stations in Basra, Iraq. Demographic data, types of skin reactions, systemic manifestations and kinds of treatments were collected. Results: Overall, 79 % of fishermen in all three Marine stations gave a history of having been stung. The common sites of sings were the hands and arms followed by the legs. Most fishermen claimed that stings led to skin reactions within 5 minutes. The presenting complaints were itching, burning sensation, and erythematic wheals. A few days after the sting, new groups of painless and itchy erythematous monomorphic papular rashes developed at the site of the sting in 62 % of cases as a delayed type of skin reaction that resolved spontaneously. The local remedies commonly used by the fishermen were seawater, tap water and ice. A few fishermen considered stings as insignificant and did not think there was a need to seek medical help. Conclusions: We conclude that jellyfish causes many stings among fishermen in the Basra region. Their stings lead to immediate and delayed skin reactions. Self-treatment by topical remedies is common.

Al-rubiay Kk; Al-musaoi Ha; Alrubaiy L; Al-freje Mg

290

PREDICTION MODEL OF JELLYFISH BLOOMS BASED IN SEA SURFACE TEMPERATURE AND SALINITY AND OTHER WATER QUALITY INDICATORS  

E-print Network

The objective of this work is to create a processing chain that will transform physical parameters and biological ocean data (Chlorophyll concentration, salinity, temperature and winds) sampled at a RxR meter resolution into the probability of jellyfish occurrence at each pixel. The feature extraction and classification methodology will be developed using ground truth from in situ measurements

Laura Moreno-patricio; Laia Romero; Aureli Soria-frisch

291

Synthesis of hierarchical tree-like and jellyfish-like silicon oxide nanostructures.  

PubMed

Hierarchical tree-like and jellyfish-like SiOx nanostructures have been synthesized by annealing a mixture of carbon coated Ni nanoparticles (Ni@C) and SiO2 powers under argon atmosphere at 1400 degrees C. The synthesized products were characterized by electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. The tree-like SiOx nanostructures consisting of the trunks and many branches and subbranches with diminishing diameters have been observed for the first time. The diameters of the trunks are about 150-1000 nm, and the branches become more slender for each branching, ultimately to 20-40 nm in diameter for the ends. The jellyfish-like SiOx nanostructures are constructed by the catalyst heads with sizes of about 1-10 microm and many connected quasi-aligned SiOx nanowires with diameters about 20-40 nm. The Ni species of the Ni@C nanoparticles acts as the catalyst and the surface carbon as the reducing agent for carbothermal reduction of SiO2. The experimental results suggest that the formation of different SiOx nanostructures mainly depend on the dimensions of the congregated Ni catalyst droplets during the reaction process and the growth mechanism is reasonably discussed. PMID:19504941

Huo, Kaifu; Fu, Jijiang; Lu, Bin; Ni, Hongwei; Hu, Yemin; Chu, Paul K; Hu, Zheng

2009-06-01

292

Purification, characterization and cDNA cloning of a novel lectin from the jellyfish Nemopilema nomurai.  

PubMed

A lectin (designated NnL) from a jellyfish Nemopilema nomurai was purified by ion-exchange chromatography followed by affinity chromatography. The apparent molecular mass of NnL was 28kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis under reducing and nonreducing conditions. NnL agglutinated horse erythrocytes, the gram-positive bacterium Bacillus subtilis and gram-negative bacterium Escherichia coli K12. The hemagglutinating activity of NnL was inhibited by N-acetyl-D-galactosamine N-acetylneuraminic acid and N-glycolylneuraminic acid. Bovine submaxillary mucin was the potent inhibitor of the hemagglutinating activity of NnL among the glycoproteins tested. cDNA cloning of NnL revealed that its primary structure contained part of a fibrinogen-like domain. The deduced amino acid sequence of NnL showed no significant sequence identities to other known lectins. On the other hand NnL showed high sequence identity to a predicted protein of the sea anemone Nematostella vectensis suggesting that NnL may belong to a novel lectin family in metazoans. This is the first report to describe the purification characterization and cDNA cloning of a jellyfish lectin. PMID:20102748

Imamichi, Yoshitaka; Yokoyama, Yoshihiro

2010-05-01

293

A jellyfish-inspired jet propulsion robot actuated by an iris mechanism  

NASA Astrophysics Data System (ADS)

A jellyfish-inspired jet propulsion robot (JetPRo) is designed, fabricated, and characterized with the objective of creating a fast-swimming uncrewed undersea vehicle. JetPRo measures 7.9 cm in height, 5.7 cm in diameter and is designed to mimic the proficient jetting propulsion mechanism used by the hydromedusa Sarsia tubulosa, which measures approximately 1 cm in diameter. In order to achieve the uniform-bell contraction used by S. tubulosa, we develop a novel circumferential actuation technique based on a mechanical iris diaphragm. When triggered, this mechanism induces a volumetric change of a deformable silicone cavity to expel a jet of fluid and produces positive thrust. A theoretical jetting model is used to optimize JetPRo’s gait for maximum steady-state swimming velocity, a result achieved by minimizing the timing between the contraction and relaxation phases. We validate this finding empirically and quantify the swimming performance of the robot using video tracking and time resolved digital particle image velocimetry. JetPRo was able to produce discrete vortex rings shed before pinch off and swim upwards with a maximum steady-state velocity of 11.6 cm s-1, outperforming current state-of-the-art robotic jellyfish in velocity as well as diameter-normalized velocity.

Marut, Kenneth; Stewart, Colin; Michael, Tyler; Villanueva, Alex; Priya, Shashank

2013-09-01

294

The HOX-like gene Cnox2Pc is expressed at the anterior region in all life cycle stages of the jellyfish Podocoryne carnea  

Microsoft Academic Search

The marine jellyfish Podocoryne carnea (Cnidaria, Hydrozoa) has a metagenic life cycle consisting of a larva, a colonial polyp and a free-swimming jellyfish (medusa).\\u000a To study the function of HOX genes in primitive diploblastic animals we screened a library of P. carnea cDNA using PCR primers derived from the most conserved regions in helix 1 and helix 3 of the

Liria M. Masuda-Nakagawa; H. Gröer; Birgit L. Aerne; Volker Schmid

2000-01-01

295

Polyspermy block in jellyfish eggs: collaborative controls by Ca(2+) and MAPK.  

PubMed

Jellyfish eggs neither undergo apparent cortical reaction nor show any significant change in the membrane potential at fertilization, but nevertheless show monospermy. Utilizing the perfectly transparent eggs of the hydrozoan jellyfish Cytaeis uchidae, here we show that the polyspermy block is accomplished via a novel mechanism: a collaboration between Ca(2+) and mitogen-activated protein kinase (MAPK). In Cytaeis, adhesion of a sperm to the animal pole surface of an egg was immediately followed by sperm-egg fusion and initiation of an intracellular Ca(2+) rise from this site. The elevated Ca(2+) levels lasted for several minutes following the sperm-egg fusion. The Ca(2+) rise proved to be necessary and sufficient for a polyspermy block, as inhibiting a Ca(2+) rise with EGTA promoted polyspermy, and conversely, triggering a Ca(2+) rise by inositol 1,4,5-trisphosphate (IP3) or excess K(+) immediately abolished the egg's capacity for sperm-egg fusion. A Ca(2+) rise at fertilization or by artificial stimulations evoked dephosphorylation of MAPK in eggs. The eggs in which phosphorylated MAPK was maintained by injection of mRNA for MAPK kinase kinase (Mos), like intact eggs, exhibited a Ca(2+) rise at fertilization or by IP3 injection, and shut down the subsequent sperm-egg fusion. However, the Mos-expressing eggs became capable of accepting sperm following the arrest of Ca(2+) rise. In contrast, addition of inhibitors of MAPK kinase (MEK) to unfertilized eggs caused MAPK dephosphorylation without elevating Ca(2+) levels, and prevented sperm-egg fusion. Rephosphorylation of MAPK by injecting Mos mRNA after fertilization recovered sperm attraction, which is known to be another MAPK-dependent event, but did not permit subsequent sperm-egg fusion. Thus, it is possible that MAPK dephosphorylation irreversibly blocks sperm-egg fusion and reversibly suppresses sperm attraction. Collectively, our data suggest that both the fast and late mechanisms dependent on Ca(2+) and MAPK, respectively, ensure a polyspermy block in jellyfish eggs. PMID:24809798

Arakawa, Mio; Takeda, Noriyo; Tachibana, Kazunori; Deguchi, Ryusaku

2014-08-01

296

Long-Term Fluctuations in Circalunar Beach Aggregations of the Box Jellyfish Alatina moseri in Hawaii, with Links to Environmental Variability  

PubMed Central

The box jellyfish Alatina moseri forms monthly aggregations at Waikiki Beach 8–12 days after each full moon, posing a recurrent hazard to swimmers due to painful stings. We present an analysis of long-term (14 years: Jan 1998– Dec 2011) changes in box jellyfish abundance at Waikiki Beach. We tested the relationship of beach counts to climate and biogeochemical variables over time in the North Pacific Sub-tropical Gyre (NPSG). Generalized Additive Models (GAM), Change-Point Analysis (CPA), and General Regression Models (GRM) were used to characterize patterns in box jellyfish arrival at Waikiki Beach 8–12 days following 173 consecutive full moons. Variation in box jellyfish abundance lacked seasonality, but exhibited dramatic differences among months and among years, and followed an oscillating pattern with significant periods of increase (1998–2001; 2006–2011) and decrease (2001–2006). Of three climatic and 12 biogeochemical variables examined, box jellyfish showed a strong, positive relationship with primary production, >2 mm zooplankton biomass, and the North Pacific Gyre Oscillation (NPGO) index. It is clear that that the moon cycle plays a key role in synchronizing timing of the arrival of Alatina moseri medusae to shore. We propose that bottom-up processes, likely initiated by inter-annual regional climatic fluctuations influence primary production, secondary production, and ultimately regulate food availability, and are therefore important in controlling the inter-annual changes in box jellyfish abundance observed at Waikiki Beach. PMID:24194856

Chiaverano, Luciano M.; Holland, Brenden S.; Crow, Gerald L.; Blair, Landy; Yanagihara, Angel A.

2013-01-01

297

Antioxidant activity of the giant jellyfish Nemopilema nomurai measured by the oxygen radical absorbance capacity and hydroxyl radical averting capacity methods.  

PubMed

The giant jellyfish Nemopilema nomurai (reaching sizes of up to 2 m diameter and 150 kg), which forms dense blooms, has caused extensive damage to fisheries by overloading trawl nets, while its toxic nematocysts cause dermatological symptoms. Giant jellyfish are currently discarded on the grounds of pest control. However, the giant jellyfish is considered to be edible and is part of Chinese cuisine. Therefore, we investigated whether any benefits for human health may be derived from consumption of the jellyfish in order to formulate medicated diets. Antioxidant activity of Nemopilema nomurai was measured using the oxygen radical absorbance capacity (ORAC) and hydroxyl radical averting capacity (HORAC) methods. Based on the results, the ORAC value of the giant jellyfish freeze-dried sample was 541 µmol trolox equivalent (TE)/100 g and the HORAC value was 3,687 µmol gallic acid equivalent (GAE)/100 g. On the other hand, the IC50 value of hydroxyl radical scavenging activity measured by using the electron spin resonance method was 3.3%. In conclusion, the results suggest that the freeze-dried powder of the giant jellyfish Nemopilema nomurai is a potentially beneficial food for humans. PMID:21667028

Harada, Kazuki; Maeda, Toshimichi; Hasegawa, Yoshiro; Tokunaga, Takushi; Ogawa, Shinya; Fukuda, Kyoko; Nagatsuka, Norie; Nagao, Keiko; Ueno, Shunshiro

2011-01-01

298

Phospholipase A2 in cnidaria.  

PubMed

Phospholipase A2 (PLA2) is an enzyme present in snake and other venoms and body fluids. We measured PLA2 catalytic activity in tissue homogenates of 22 species representing the classes Anthozoa, Hydrozoa, Scyphozoa and Cubozoa of the phylum Cnidaria. High PLA2 levels were found in the hydrozoan fire coral Millepora sp. (median 735 U/g protein) and the stony coral Pocillopora damicornis (693 U/g) that cause skin irritation upon contact. High levels of PLA2 activity were also found in the acontia of the sea anemone Adamsia carciniopados (293 U/g). Acontia are long threads containing nematocysts and are used in defense and aggression by the animal. Tentacles of scyphozoan and cubozoan species had high PLA2 activity levels: those of the multitentacled box jellyfish Chironex fleckeri contained 184 U/g PLA2 activity. The functions of cnidarian PLA2 may include roles in the capture and digestion of prey and defense of the animal. The current observations support the idea that cnidarian PLA2 may participate in the sting site irritation and systemic envenomation syndrome resulting from contact with cnidarians. PMID:15581805

Nevalainen, Timo J; Peuravuori, Heikki J; Quinn, Ronald J; Llewellyn, Lyndon E; Benzie, John A H; Fenner, Peter J; Winkel, Ken D

2004-12-01

299

The marine biologist--Bob Endean.  

PubMed

Bob Endean was a dedicated marine biologist with an extensive knowledge of coral reef communities in the Great Barrier Reef and fauna in subtropical Queensland waters. He commenced a study of venomous and poisonous marine animals dangerous to man at a time when the field was new, employing a variety of techniques to investigate the venom apparatus, mode of delivery of venom or toxin, mode of toxic action on excitable tissues, and biochemistry of venom or toxin. Determination of the pharmacological properties of crude venom from Conus marine snails advanced characterization of conotoxins by later workers. A study of four types of nematocysts from the box-jellyfish Chironex fleckeri provided information as to their structure, function, and mechanism of discharge; myotoxins T1 and T2 were isolated from microbasic mastigophores. Endean studied poisonous stonefish (Synanceia trachynis) and, with Ann Cameron, scorpionfish (Notesthes robusta); investigations of ciguatera and of paralytic shellfish poisoning were initiated. He organized the collection of Australian frogs which led to the isolation of caerulein by Erspamer in Italy. Endean highlighted the ecological danger of the population explosion of the crown-of-thorns starfish (Acanthaster planci) and provided the impetus for the creation of the Great Barrier Reef Marine Park. PMID:16952385

Hawgood, Barbara J

2006-12-01

300

Detection of common antigenic sites in lethal proteins of non-related animal venoms.  

PubMed

Monoclonal antibodies neutralizing specific coelenterate lethal toxins were used to determine the presence of homologous antigenic sites on toxin proteins of a rattlesnake (Crotalus durissus terrificus), a hornet (Vespa orientalis) and the sea wasp (Chironex fleckeri). An anti-Portuguese man-o'war toxin antibody was found useful for isolating a C. d. terrificus toxin. PMID:6623490

Russo, A J; Cobbs, C S; Calton, G J; Burnett, J W

1983-01-01

301

Insecticidal activity of proteinous venom from tentacle of jellyfish Rhopilema esculentum Kishinouye.  

PubMed

Insecticidal activity of proteinous venom from tentacle of jellyfish Rhopilema esculentum Kishinouye was determined against three pest species, Stephanitis pyri Fabriciusa, Aphis medicaginis Koch, and Myzus persicae Sulzer. R. esculentum full proteinous venom had different insecticidal activity against S. pyri Fabriciusa, A. medicaginis Koch, and M. persicae Sulzer. The 48 h LC50 values were 123.1, 581.6, and 716.3 microg/mL, respectively. Of the three pests, R. esculentum full proteinous venom had the most potent toxicity against S. pyri Fabriciusa, and the corrected mortality recorded at 48 h was 97.86%. So, S. pyri Fabriciusa could be a potential target pest of R. esculentum full proteinous venom. PMID:16168648

Yu, Huahua; Liu, Xiguang; Dong, Xiangli; Li, Cuiping; Xing, Ronge; Liu, Song; Li, Pengcheng

2005-11-15

302

Factors affecting the protease activity of venom from jellyfish Rhopilema esculentum Kishinouye.  

PubMed

In this paper, the effects of some chemical and physical factors such as temperature, pH values, glycerol, and divalent metal cations on the protease activity of venom from jellyfish, Rhopilema esculentum Kishinouye, were assayed. Protease activity was dependent on temperature and pH values. Zn(2+), Mg(2+), and Mn(2+) in sodium phosphate buffer (0.02M, pH 8.0) could increase protease activity. Mn(2+) had the best effects among the three metal cations and the effect was about 20 times of that of Zn(2+) or Mg(2+) and its maximal protease activity was 2.3x10(5)U/mL. EDTA could increase protease activity. PMSF had hardly affected protease activity. O-Phenanthroline and glycerol played an important part in inhibiting protease activity and their maximal inhibiting rates were 87.5% and 82.1%, respectively. PMID:16213717

Li, Cuiping; Yu, Huahua; Liu, Song; Xing, Ronge; Guo, Zhanyong; Li, Pengcheng

2005-12-15

303

Structural analysis of O-glycans of mucin from jellyfish (Aurelia aurita) containing 2-aminoethylphosphonate.  

PubMed

The structure of O-glycan in qniumucin (Q-mucin), which is a novel mucin extracted from jellyfish, was analyzed by a combination of NMR and ESI-MS/MS. A previously unidentified monosaccharide involved in the glycan chains was determined to be N-acetylgalactosamine (GalNAc) substituted by 2-aminoethylphosphonate (AEP) at the C-6. The O-glycans in Q-mucin from Aurelia aurita were proved to be mainly composed of three monosaccharides: GalNAc, AEP-(O-->6)-GalNAc, and P-6-GalNAc. To the best of our knowledge, this is the first example of an O-glycan structure of glycoproteins containing AEP. This exceptionally simple structure of Q-mucin and its potential use in material science and technology are revealed. PMID:19732869

Urai, Makoto; Nakamura, Takemichi; Uzawa, Jun; Baba, Takayuki; Taniguchi, Kayoko; Seki, Hiroko; Ushida, Kiminori

2009-11-01

304

Exploring vortex enhancement and manipulation mechanisms in jellyfish that contributes to energetically efficient propulsion  

PubMed Central

The ability of animals to propel themselves efficiently through a fluid medium is ecologically advantageous. Flexible components that influence vortex interactions are widespread among animal propulsors. However the mechanisms by which vortices are enhanced and appropriately positioned for thrust generation are still poorly understood. Here, we describe how kinematic propulsor movements of a jellyfish can enhance and reposition a vortex ring that allows the recapture of wake energy for secondary thrust generation and efficient locomotion. We use high-speed video and digital particle image velocimetry (DPIV) to resolve kinematics simultaneously with fluid structures. These results provide new insight into how animals can manipulate fluid structures to reduce metabolic energy demands of swimming muscles and may have implications in bio-inspired design. PMID:25346796

Gemmell, Brad J; Costello, John H; Colin, Sean P

2014-01-01

305

Cytotoxic cytochalasins from the endozoic fungus Phoma sp. of the giant jellyfish Nemopilema nomurai.  

PubMed

Four new cytochalasin derivatives (1-4), together with cytochalasin B (5), were isolated from the fungus Phoma sp. obtained from the giant jellyfish Nemopilema nomurai. The planar structure and relative stereochemistry were established by analysis of 1D and 2D NMR data. The absolute configuration was defined by the modified Mosher's method. The compounds showed significant cytotoxicity against a small panel of human solid tumor cell lines (A549, SK-OV-3, SK-MEL-2, XF 498, and HCT15) with IC(50) values in the range of 0.5-30 ?M. The cytochalasin B (5) showed obvious cytotoxicity with IC(50) of 7.9 ?M against HeLa human cervical carcinoma cells. PMID:22483395

Kim, Eun La; Li, Jian Lin; Dang, Hung The; Hong, Jongki; Lee, Chong-Ok; Kim, Dong-Kyoo; Yoon, Won Duk; Kim, Euikyung; Liu, Yonghong; Jung, Jee H

2012-05-01

306

The Occurrence of Type S1A Serine Proteases in Sponge and Jellyfish  

NASA Technical Reports Server (NTRS)

Although serine proteases are found in all kinds of cellular organisms and many viruses, the classic "chymotrypsin family" (Group S1A by th e 1998 Barrett nomenclature) has an unusual phylogenetic distribution , being especially common in animals, entirely absent from plants and protists, and rare among fungi. The distribution in Bacteria is larg ely restricted to the genus Streptomyces, although a few isolated occ urrences in other bacteria have been reported. The family may be enti rely absent from Archaea. Although more than a thousand sequences have been reported for enzymes of this type from animals, none of them ha ve been from early diverging phyla like Porifera or Cnidaria, We now report the existence of Group SlA serine proteases in a sponge (phylu m Porifera) and a jellyfish (phylum Cnidaria), making it safe to conc lude that all animal groups possess these enzymes.

Rojas, Ana; Doolittle, Russell F.

2003-01-01

307

Evolutionary aspects of developmentally regulated helix-loop-helix transcription factors in striated muscle of jellyfish.  

PubMed

The function of basic helix-loop-helix (bHLH) proteins in cell differentiation was shown to be conserved from Drosophila to vertebrates, exemplified by the function of MyoD in striated muscle differentiation. In phylogeny striated muscle tissue appears first in jellyfish and the question of its evolutionary position is controversially discussed. For this reason we have studied the developmental role of myogenic bHLH genes in medusa development. Based on their dimerization ability, four genes of the bHLH family of transcription factors were isolated from the hydrozoan jellyfish Podocoryne carnea. While the proteins Id and Ash group with cognate family members from bilaterians, Net-like and JellyD1 could not be unequivocally classified. Id is expressed during the medusa budding process and in the adult medusa, Ash and Net-like are expressed in all life cycle stages from egg to adult medusa and JellyD1 is expressed in the blastula and gastrula stages, the planula larva, and in late medusa bud stages. The dimerization specificity, the expression pattern, and the conservation of two residues specific for a MyoD bHLH domain suggest that JellyD1 is related to an ancestral MyoD gene. Id, Net-like, and JellyD1 are either expressed in the entocodon or its derived tissues, the striated and smooth muscle of the bell. These findings strengthen the hypothesis that the entocodon is a mesoderm-like structure and that the common ancestor of Cnidaria and Bilateria was more complex in cell-type architecture and body organization than commonly thought. PMID:12648485

Müller, Peter; Seipel, Katja; Yanze, Nathalie; Reber-Müller, Susanne; Streitwolf-Engel, Ruth; Stierwald, Michael; Spring, Jürg; Schmid, Volker

2003-03-15

308

Cytotoxicity and hemolytic activity of jellyfish Nemopilema nomurai (Scyphozoa: Rhizostomeae) venom.  

PubMed

The recent bloom of a giant jellyfish Nemopilema nomurai has caused a danger to sea bathers and fishery damages in the waters of China, Korea, and Japan. The present study investigated the cytotoxic and hemolytic activities of crude venom extract of N. nomurai using a number of in vitro assays. The jellyfish venom showed a much higher cytotoxic activity in H9C2 heart myoblast than in C2C12 skeletal myoblast (LC(50)=2 microg/mL vs. 12 microg/mL, respectively), suggesting its possible in vivo selective toxicity on cardiac tissue. This result is consistent with our previous finding that cardiovascular function is a target of the venom. In order to determine the stability of N. nomurai venom, its cytotoxicity was examined under the various temperature and pH conditions. The activity was relatively well retained at low environmental temperature (or=60 degrees C). In pH stability test, the venom has abruptly lost its activity at low pH environment (pH

Kang, Changkeun; Munawir, Al; Cha, Mijin; Sohn, Eun-Tae; Lee, Hyunkyoung; Kim, Jong-Shu; Yoon, Won Duk; Lim, Donghyun; Kim, Euikyung

2009-07-01

309

Isolation and Characterization of a Novel Protein Toxin from the Hawaiian Box Jellyfish (Sea Wasp) Carybdea alata  

Microsoft Academic Search

The box jellyfish (sea wasp) Carybdea alata Reynaud, 1830 (Cubozoa) is distributed widely in the tropics. The sting of C. alata causes severe pain and cutaneous inflammation in humans. We successfully isolated C. alata toxin-A (CaTX-A, 43 kDa) and -B (CaTX-B, 45 kDa) for the first time from the tentacle of C. alata collected at a site along the Hawaiian

Hiroshi Nagai; Kyoko Takuwa; Masahiro Nakao; Bryan Sakamoto; Gerald L Crow; Terumi Nakajima

2000-01-01

310

Stable isotope and biochemical fractionation in the marine pelagic food chain: the jellyfish Pelagia noctiluca and net zooplankton  

Microsoft Academic Search

In our field study we analyzed the C and H isotopic and biochemical (C, N, P, protein, lipid, carbohydrate) composition of the jellyfish Pelagia noctiluca (collected from the Gulf of Trieste in 1985 to 1986) and its presumed diet-net zooplankton. The mean d 13C (-18.8‰) and d D (-58.4‰) ratios of P. noctiluca showed enrichment in heavy isotopes relative to

A. Malej; J. Faganeli; J. Pezdi?

1993-01-01

311

[Spectral diversity among the members of the family of Green Fluorescent Protein in hydroid jellyfish (Cnidaria, Hydrozoa)].  

PubMed

The cDNAs encoding the genes of new proteins homologous to the well-known Green Fluorescent Protein (GFP) from the hydroid jellyfish Aequorea victoria were cloned. Two green fluorescent proteins from one un-identified anthojellyfish, a yellow fluorescent protein from Phialidium sp., and a nonfluorescent chromoprotein from another unidentified anthojellyfish were characterized. Thus, a broad diversity of GFP-like proteins among the organisms of the class Hydrozoa in both spectral properties and primary structure was shown. PMID:15787213

Ianushevich, Iu G; Shagin, D A; Fradkov, A F; Shakhbazov, K S; Barsova, E V; Gurskaia, N G; Labas, Iu A; Matts, M V; Luk'ianov, k A; Lul'ianov, S A

2005-01-01

312

First Complete Mitochondrial Genome Sequence from a Box Jellyfish Reveals a Highly Fragmented Linear Architecture and Insights into Telomere Evolution  

PubMed Central

Animal mitochondrial DNAs (mtDNAs) are typically single circular chromosomes, with the exception of those from medusozoan cnidarians (jellyfish and hydroids), which are linear and sometimes fragmented. Most medusozoans have linear monomeric or linear bipartite mitochondrial genomes, but preliminary data have suggested that box jellyfish (cubozoans) have mtDNAs that consist of many linear chromosomes. Here, we present the complete mtDNA sequence from the winged box jellyfish Alatina moseri (the first from a cubozoan). This genome contains unprecedented levels of fragmentation: 18 unique genes distributed over eight 2.9- to 4.6-kb linear chromosomes. The telomeres are identical within and between chromosomes, and recombination between subtelomeric sequences has led to many genes initiating or terminating with sequences from other genes (the most extreme case being 150 nt of a ribosomal RNA containing the 5? end of nad2), providing evidence for a gene conversion–based model of telomere evolution. The silent-site nucleotide variation within the A. moseri mtDNA is among the highest observed from a eukaryotic genome and may be associated with elevated rates of recombination. PMID:22117085

Smith, David Roy; Kayal, Ehsan; Yanagihara, Angel A.; Collins, Allen G.; Pirro, Stacy; Keeling, Patrick J.

2012-01-01

313

Jellyfish Support High Energy Intake of Leatherback Sea Turtles (Dermochelys coriacea): Video Evidence from Animal-Borne Cameras  

E-print Network

The endangered leatherback turtle is a large, highly migratory marine predator that inexplicably relies upon a diet of lowenergy gelatinous zooplankton. The location of these prey may be predictable at large oceanographic scales, given that leatherback turtles perform long distance migrations (1000s of km) from nesting beaches to high latitude foraging grounds. However, little is known about the profitability of this migration and foraging strategy. We used GPS location data and video from animal-borne cameras to examine how prey characteristics (i.e., prey size, prey type, prey encounter rate) correlate with the daytime foraging behavior of leatherbacks (n = 19) in shelf waters off Cape Breton Island, NS, Canada, during August and September. Video was recorded continuously, averaged 1:53 h per turtle (range 0:08–3:38 h), and documented a total of 601 prey captures. Lion’s mane jellyfish (Cyanea capillata) was the dominant prey (83–100%), but moon jellyfish (Aurelia aurita) were also consumed. Turtles approached and attacked most jellyfish within the camera’s field of view and appeared to consume prey completely. There was no significant relationship between encounter rate and dive duration (p = 0.74, linear mixed-effects models). Handling time increased with prey size regardless of prey species (p = 0.0001). Estimates of energy intake averaged 66,018 kJNd 21 but were as high as 167,797 kJNd 21 corresponding to turtles consuming

Susan G. Heaslip; Sara J. Iverson; W. Don Bowen; Michael C. James

314

Jellyfish and Juvenile Salmon Associations with Oceanographic Characteristics during Warm and Cool Years in the Eastern Bering Sea  

E-print Network

Abstract: We explored possible associations between jellyfish biomass (Aequorea spp., Aurelia labiata, Chrysaora melanaster, and Cyanea capillata), juvenile salmon (Oncorhynchus keta, O. nerka, O. gorbuscha, O. kisutch, and O. tshawytscha) abundance, and oceanographic characteristics (temperature, salinity, chlorophyll-a, and bottom depth) during two warm years (2004, 2005) and two cool years (2006, 2007) in the eastern Bering Sea from the annual Bering-Aleutian Salmon International Surveys (US BASIS). A significant difference was observed in the mean relative biomass of the four jellyfish species in response to the various conditions in warm versus cool years. Our results indicated that juvenile O. tshawytscha were significantly associated with cooler temperatures in only cool years and shallower bottom depths in all years. Juvenile O. kisutch were associated with shallower than average bottom depths for all years and juvenile O. keta had only cool-year associations with lower salinities and shallower bottom depths. Similar spatial distributions were seen between jellyfish and juvenile salmon, suggesting the possibility of competition. Immature O. keta were significantly associated with the same physical ocean factors as Aequorea spp. during fall warm years, indicating a potential for interaction.

Kristin Cieciel; Edward V. Farley; Lisa B. Eisner

315

Diversity, Phylogeny and Expression Patterns of Pou and Six Homeodomain Transcription Factors in Hydrozoan Jellyfish Craspedacusta sowerbyi  

PubMed Central

Formation of all metazoan bodies is controlled by a group of selector genes including homeobox genes, highly conserved across the entire animal kingdom. The homeobox genes from Pou and Six classes are key members of the regulation cascades determining development of sensory organs, nervous system, gonads and muscles. Besides using common bilaterian models, more attention has recently been targeted at the identification and characterization of these genes within the basal metazoan phyla. Cnidaria as a diploblastic sister group to bilateria with simple and yet specialized organs are suitable models for studies on the sensory organ origin and the associated role of homeobox genes. In this work, Pou and Six homeobox genes, together with a broad range of other sensory-specific transcription factors, were identified in the transcriptome of hydrozoan jellyfish Craspedacusta sowerbyi. Phylogenetic analyses of Pou and Six proteins revealed cnidarian-specific sequence motifs and contributed to the classification of individual factors. The majority of the Craspedacusta sowerbyi Pou and Six homeobox genes are predominantly expressed in statocysts, manubrium and nerve ring, the tissues with sensory and nervous activities. The described diversity and expression patterns of Pou and Six factors in hydrozoan jellyfish highlight their evolutionarily conserved functions. This study extends the knowledge of the cnidarian genome complexity and shows that the transcriptome of hydrozoan jellyfish is generally rich in homeodomain transcription factors employed in the regulation of sensory and nervous functions. PMID:22558464

Hroudova, Miluse; Vojta, Petr; Strnad, Hynek; Krejcik, Zdenek; Ridl, Jakub; Paces, Jan; Vlcek, Cestmir; Paces, Vaclav

2012-01-01

316

Jellyfish stings  

MedlinePLUS

... okay, but make sure you do NOT get sand in the wound). Protect affected area if possible. ... Determine the following information: Patient's age, weight, and condition Name of the marine animal, if possible Time stung

317

Behavior of the giant jellyfish Nemopilema nomurai in the East China Sea and East\\/Japan Sea during the summer of 2005: A numerical model approach using a particle-tracking experiment  

Microsoft Academic Search

The contribution of physical processes in the distribution of the giant jellyfish Nemopilema nomurai in the northern East China (ECS) Yellow (YS) and East\\/Japan (EJS) seas in summer 2005 was simulated by a Lagrangian particle-tracking experiment based on ROMS (Regional Ocean Modeling System). The particles representing jellyfish were released in the western YS between the Shandong Peninsula and the Changjiang

Jae-Hong Moon; Ig-Chan Pang; Joon-Yong Yang; Won Duk Yoon

2010-01-01

318

Crude Venom from Nematocysts of the Jellyfish Pelagia noctiluca as a Tool to Study Cell Physiology.  

PubMed

Marine animals represent a good model for toxicological investigations, being a source of novel bioactive substances considered as a suitable research tool. Among stinging animals, Cnidarians possess specialized cells, termed nematocytes, containing an inverted tubule and toxins, synergistically responsible for mechanisms of defence and predation. Such compounds include proteins and secondary metabolites with toxic action. To elucidate the effects of Cnidarian venom upon cell targets, this short review reports on the biological activity of venom extracted from nematocysts of the jellyfish Pelagia noctiluca, whose "blooming" is well known in the Mediterranean Sea. The effects on erythrocytes and on cultured cells, from both mammals and invertebrates, along with in vivo studies, are here being considered. What is known about the biological activity of Pelagia noctiluca crude venom accounts for a notable effect at different levels, suggesting that cell damage may be due to a pore formation mechanism on cell membrane target leading to osmotic lysis, and /or to oxidative stress events. In this light, the study of venom activity may contribute to i) validate suitable biological assays for venom testing; ii) elucidate cell function features; iii) understand the pathophysiology of envenoming. PMID:25353952

Morabito, Rossana; La Spada, Giuseppina; Crupi, Rosalia; Esposito, Emanuela; Marino, Angela

2014-10-28

319

The state of water in living systems: from the liquid to the jellyfish.  

PubMed

The status of water in living systems is reviewed both from philosophical and scientific viewpoints. Starting from antique Mediterranean civilizations (Sumerian, Egyptian, Hebrew, Greek), a world trip is proposed through Norse myths, Siberian Shamanism, Hinduism, Taoism, Buddhism, Shinto, Mayan, Aztec, Inca, Aboriginal and African philosophies in order to convince that all humans share the same qualitative idea that water was a pre-requisite for life apparition. The quantitative aspect of the problem is further analyzed at the light of the scientific contributions from two leading scientists: R.A. Gortner and E.T. Jaynes. With Gortner's work it is demonstrated using the concrete example of the Jellyfish submitted at a Faraday discussion held in London in 1930, how a paradigm shift has occurred in the thirties concerning the status of bound water in the living cell. With Jaynes' work, the disastrous consequences of the entrenchment of diffusion theory in biology are critically examined and the exact meaning of the second law of thermodynamics for biological systems is given using the concrete example of muscle contraction. In conclusion, the importance of distinguishing between an ontological and epistemological level of knowledge is stressed and suggestions for reconciling scientific and philosophical approaches are given. PMID:16359619

Henry, M

2005-12-14

320

Factors influencing hemolytic activity of venom from the jellyfish Rhopilema esculentum Kishinouye.  

PubMed

In this study, hemolytic activity of venom from the jellyfish Rhopilema esculentum Kishinouye and some factors affecting it were assayed. The HU(50) of R. esculentum full venom (RFV) against chicken erythrocytes was 3.40 microg/ml and a Hill coefficient value was 1.73 suggesting at least two molecules participated in hemolytic activity. The hemolytic activity of RFV was affected by some chemical and physical factors such as divalent cations, EDTA, (NH(4))(2)SO(4), pH and temperature. In the presence of Mg(2+), Cu(2+), Zn(2+), Fe(2+), Ca(2+) (>or=2 mM), Mn(2+) ((>or=1 mM), EDTA ((>or=2 mM) and (NH(4))(2)SO(4), the hemolytic activity of RFV was reduced. RFV had strong hemolytic activity at the pH 6-10 and the hemolytic ratios were 0.95-1.19. Hemolytic activity was temperature-sensitive and when RFV was pre-incubated at temperatures over 40 degrees C, it was sharply reduced. PMID:17306433

Yu, Huahua; Li, Cuiping; Li, Ronggui; Xing, Ronge; Liu, Song; Li, Pengcheng

2007-07-01

321

Radical scavenging activity of protein from tentacles of jellyfish Rhopilema esculentum.  

PubMed

In this study, radical scavenging activity of protein from tentacles of jellyfish Rhopilema esculentum (R. esculentum) was assayed including superoxide anion radical and hydroxyl radical scavenging. The protein samples showed strong scavenging activity on superoxide anion radical and values EC50 of full protein (FP), first fraction (FF), second fraction (SF), and 30% (NH4)2 SO4 precipitate (Fr-1) were 2.65, 7.28, 1.10, and 22.51 microg/mL, respectively, while values EC50 of BHA, BHT, and alpha-tocopherol were 31, 61, and 88 microg/mL, respectively. Also, the protein samples had strong scavenging effect on hydroxyl radical and the values EC50 of FP, FF, SF, Fr-1, and Fr-2 were 48.91, 27.72, 1.82, 16.36, and 160.93 microg/mL, but values EC50 of Vc and mannitol were 1907 and 4536 microg/mL, respectively. Of the five protein samples, SF had the strongest radical scavenging activity and may have a use as a possible supplement in the food and pharmaceutical industries. The radical scavenging activity was stable at high temperature so that R. esculentum may be used as a kind of natural functional food. PMID:15863337

Yu, Huahua; Liu, Xiguang; Xing, Ronge; Liu, Song; Li, Cuiping; Li, Pengcheng

2005-05-16

322

Jellyfish skin polysaccharides: extraction and inhibitory activity on macrophage-derived foam cell formation.  

PubMed

In this work, response surface methodology was used to determine optimum conditions for extraction of polysaccharides from jellyfish skin (JSP). The optimum parameters were found to be raw material to water ratio 1:7.5 (w/v), extraction temperature 100°C and extraction time 4h. Under these conditions, the JSP yield reached 1.007 mg/g. Papain (15 U/mL) in combination with Sevag reagent was beneficial in removing proteins from JSP. After precipitation with ethanol at final concentration of 40%, 60% and 80% in turn, three polysaccharide fractions of JSP1, JSP2 and JSP3 were obtained from JSP, respectively. The three fractions exhibited different physicochemical properties with respect to molecular weight distribution, monosaccharide composition, infrared absorption spectra, and glycosyl bond composition. In addition, JSP3 showed strong inhibitory effects on oxidized low-density lipoprotein (oxLDL) induced conversion of macrophages into foam cells, which possibly attributed to the down-regulation of some atherogenesis-related gene expressions. PMID:24721094

Zhang, Hai-Lin; Cui, Shao-Hua; Zha, Xue-Qiang; Bansal, Vibha; Xue, Lei; Li, Xiao-Long; Hao, Ran; Pan, Li-Hua; Luo, Jian-Ping

2014-06-15

323

Proteomic characterisation of toxins isolated from nematocysts of the South Atlantic jellyfish Olindias sambaquiensis.  

PubMed

Surprisingly little is known of the toxic arsenal of cnidarian nematocysts compared to other venomous animals. Here we investigate the toxins of nematocysts isolated from the jellyfish Olindias sambaquiensis. A total of 29 unique ms/ms events were annotated as potential toxins homologous to the toxic proteins from diverse animal phyla, including cone-snails, snakes, spiders, scorpions, wasp, bee, parasitic worm and other Cnidaria. Biological activities of these potential toxins include cytolysins, neurotoxins, phospholipases and toxic peptidases. The presence of several toxic enzymes is intriguing, such as sphingomyelin phosphodiesterase B (SMase B) that has only been described in certain spider venoms, and a prepro-haystatin P-IIId snake venom metalloproteinase (SVMP) that activates coagulation factor X, which is very rare even in snake venoms. Our annotation reveals sequence orthologs to many representatives of the most important superfamilies of peptide venoms suggesting that their origins in higher organisms arise from deep eumetazoan innovations. Accordingly, cnidarian venoms may possess unique biological properties that might generate new leads in the discovery of novel pharmacologically active drugs. PMID:23688393

Weston, Andrew J; Chung, Ray; Dunlap, Walter C; Morandini, André C; Marques, Antonio C; Moura-da-Silva, Ana M; Ward, Malcolm; Padilla, Gabriel; da Silva, Luiziana Ferreira; Andreakis, Nikos; Long, Paul F

2013-09-01

324

Jellyfish: Special Tools for Biological Research on Earth and in Space  

NASA Technical Reports Server (NTRS)

The most intriguing nature of the jellyfish polyps is their ability to metamorphose, giving rise to tiny immature medusae called ephyrae which have a different form or shape from the polyps. The Aurelia Metamorphosis Test System was used to determine the subtle effects of hydrocarbons found in oil spills and the effects of X-irradiation on developing ephyrae. Currently, this test system is used to determine the effects of the gravity-less environment of outer space on the development and behavior of ephyrae. For this purpose, the effects of clinostat rotation on development of the ephyrae and their gravity receptor are being studied. The behavior of the ephyrae during 0 gravity achieved for short intervals of 30 seconds in parabolic flight is examined. The developing ephyrae and the mature ephyrae are exposed to gravity-less environment of outer space via a six or seven day shuttle experiment. If gravity receptors do form in outer space, they will be studied in detail using various types of microscopes, including the electron microscope, to determin whether they developed normally in space as compared with control on Earth.

Spangenberg, Dorothy B.

1991-01-01

325

Analgesic and antibutyrylcholinestrasic activities of the venom prepared from the Mediterranean jellyfish Pelagia noctiluca (Forsskal, 1775)  

PubMed Central

Background Toxins derived from jellyfishes have been exploited as a model for the development of new drug promising applications to treat neurodegenerative diseases. The present work is aimed to evaluate the acute toxicity of crude venom of Pelagia noctiluca and then to screen the analgesic and antibutyrylcholinestrasic (anti-BuChE) activities of the crude venom and its fractions. Methods Sephadex G75 gel was used to separate crude venom of Pelagia noctiluca, which led to some fractions. In addition, in vivo analgesic and in vitro plasma antibutyrylcholinestrasic activities were carried out with Pelagia crude venom and its fractions respectively. Results The crude venom and its fractions displayed analgesic and anti-BuChE activities at different doses without inducing acute toxicity. Fraction 2 possesses the highest analgesic and antibutyrylcholinestrasic properties. The crude venom and fraction 1 had shown to possess less significant inhibitory activity against analgesic and antibutyrylcholinestrasic models. Conclusions Based on this study, the crude venom of Pelagia noctiluca is found to be a useful tool for probing pharmacological activity. The purification and the determination of chemical structures of compounds of active fractions of the venom are under investigation. PMID:22691546

2012-01-01

326

Synthesis and characterization of polypyrrole composite actuator for jellyfish unmanned undersea vehicle  

NASA Astrophysics Data System (ADS)

In this paper, we investigated two geometries of conductive polymer-metal composite actuators: stripe and axial. The stripe actuator design consisted of gold coated poly(vinylidene difluoride) (PVDF) membrane with polypyrrole film grown potentiodynamically on top and bottom in sandwich structure. For axial type actuator, a gold coated core substrate was used which can be easily dissolved after polymerization of pyrrole. Synthesis of all samples was conducted using cyclic voltammometry technique. Results indicate that axial type actuator consisting of 0.25 M Pyrrole, 0.10 M TBAP and 0.5 M KCl in aqueous solution exhibits strain up to 6% and 18 kPa blocking stress for applied potential of 6V DC after 80 sec stimulation time. The axial type of actuator also exhibits rotary motion under DC voltage in electrolytic media. Experimental data was used to establish stress-strain and energy density-time response relationships. The stripe actuator with dimensions of 20mm length, 5mm width and 63?m thickness exhibited 2.8 mm transversal deflection at 7V and 0.2 Hz. Potential applications of conducting polymer based actuators include biometric jellyfish and expressive robotic head.

Tadesse, Yonas; Brennan, Jaclyn; Smith, Colin; Long, Timothy E.; Priya, Shashank

2010-04-01

327

Construction of chitin/PVA composite hydrogels with jellyfish gel-like structure and their biocompatibility.  

PubMed

High strength chitin/poly(vinyl alcohol) (PVA) composite hydrogels (RCP) were constructed by adding PVA into chitin dissolved in a NaOH/urea aqueous solution, and then by cross-linking with epichlorohydrin (ECH) and freezing-thawing process. The RCP hydrogels were characterized by field emission scanning electron microscopy, FTIR, differential scanning calorimetry, solid-state (13)C NMR, wide-angle X-ray diffraction, and compressive test. The results revealed that the repeated freezing/thawing cycles induced the bicrosslinked networks consisted of chitin and PVA crystals in the composite gels. Interestingly, a jellyfish gel-like structure occurred in the RCP75 gel with 25 wt % PVA content in which the amorphous and crystalline PVA were immobilized tightly in the chitin matrix through hydrogen bonding interaction. The freezing/thawing cycles played an important role in the formation of the layered porous PVA networks and the tight combining of PVA with the pore wall of chitin. The mechanical properties of RCP75 were much higher than the other RCP gels, and the compressive strength was 20× higher than that of pure chitin gels, as a result of broadly dispersing stress caused by the orderly multilayered networks. Furthermore, the cell culture tests indicated that the chitin/PVA composite hydrogels exhibited excellent biocompatibility and safety, showing potential applications in the field of tissue engineering. PMID:25077674

He, Meng; Wang, Zhenggang; Cao, Yan; Zhao, Yanteng; Duan, Bo; Chen, Yun; Xu, Min; Zhang, Lina

2014-09-01

328

Pharmacological Studies of Tentacle Extract from the Jellyfish Cyanea capillata in Isolated Rat Aorta  

PubMed Central

Our previous studies demonstrated that tentacle extract (TE) from the jellyfish, Cyanea capillata, could cause a dose-dependent increase of systolic blood pressure, which seemed to be the result of direct constriction of vascular smooth muscle (VSM). The aim of this study is to investigate whether TE could induce vasoconstriction in vitro and to explore its potential mechanism. Using isolated aorta rings, a direct contractile response of TE was verified, which showed that TE could induce concentration-dependent contractile responses in both endothelium-intact and -denuded aortas. Interestingly, the amplitude of contraction in the endothelium-denuded aorta was much stronger than that in the endothelium-intact one, implying that TE might also bring a weak functional relaxation in addition to vasoconstriction. Further drug intervention experiments indicated that the functional vasodilation might be mediated by nitric oxide, and that TE-induced vasoconstriction could be attributed to calcium influx via voltage-operated calcium channels (VOCCs) from the extracellular space, as well as sarcoplasmic reticulum (SR) Ca2+ release via the inositol 1,4,5-trisphosphate receptor (IP3R), leading to an increase in [Ca2+]c, instead of activation of the PLC/DAG/PKC pathway or the sympathetic nerve system. PMID:23999662

Wang, Beilei; Zhang, Bo; Wang, Qianqian; Zhang, Zhi; Nie, Fei; Liu, Guoyan; Zheng, Jiemin; Xiao, Liang; Zhang, Liming

2013-01-01

329

Cardiovascular effects of Nemopilema nomurai (Scyphozoa: Rhizostomeae) jellyfish venom in rats.  

PubMed

Over the past few years, populations of the giant jellyfish Nemopilema nomurai (Scyphozoa: Rhizostomeae) have increased dramatically in the waters of China, Korea, and Japan without any definitive reason. This has resulted in severe damage to fisheries in the areas. During a pilot study, we observed that the venom of N. nomurai produced a functional cardiac depression in mice. However, the mechanism of action was not examined. In the present study, we investigated the cardiovascular effects of nematocyst-derived venom from N. nomurai in anesthetized rats. Venom (0.1-2.4 mg protein/kg, i.v.) produced dose-dependent hypotension (65+/-12% of initial at a cumulative dose of 3 mg/kg) and bradycardia (80+/-5% of initial at a cumulative dose of 3 mg/kg). At the highest dose, this was characterized by a transient decrease in blood pressure (phase 1) followed by a return to basal level and then a slower decrease in blood pressure (phase 2). Venom also produced a decrease in rate and force of contraction in the rat isolated atria. Interestingly, venom induced a contraction of isolated aortic rings which was blocked by felodipine but not by prazosin, suggesting the contraction is mediated by calcium channel activation. These results suggest that the negative inotropic and chronotropic effects of the venom of N. nomurai may be due to a direct effect on the heart. PMID:17069996

Kim, Euikyung; Lee, Seunghwan; Kim, Jong-Shu; Yoon, Won Duk; Lim, Donghyun; Hart, Andrew J; Hodgson, Wayne C

2006-12-15

330

Changes in bacterial community metabolism and composition during the degradation of dissolved organic matter from the jellyfish Aurelia aurita in a Mediterranean coastal lagoon.  

PubMed

Spatial increases and temporal shifts in outbreaks of gelatinous plankton have been observed over the past several decades in many estuarine and coastal ecosystems. The effects of these blooms on marine ecosystem functioning and particularly on the dynamics of the heterotrophic bacteria are still unclear. The response of the bacterial community from a Mediterranean coastal lagoon to the addition of dissolved organic matter (DOM) from the jellyfish Aurelia aurita, corresponding to an enrichment of dissolved organic carbon (DOC) by 1.4, was assessed for 22 days in microcosms (8 l). The high bioavailability of this material led to (i) a rapid mineralization of the DOC and dissolved organic nitrogen from the jellyfish and (ii) the accumulation of high concentrations of ammonium and orthophosphate in the water column. DOM from jellyfish greatly stimulated heterotrophic prokaryotic production and respiration rates during the first 2 days; then, these activities showed a continuous decay until reaching those measured in the control microcosms (lagoon water only) at the end of the experiment. Bacterial growth efficiency remained below 20 %, indicating that most of the DOM was respired and a minor part was channeled to biomass production. Changes in bacterial diversity were assessed by tag pyrosequencing of partial bacterial 16S rRNA genes, DNA fingerprints, and a cultivation approach. While bacterial diversity in control microcosms showed little changes during the experiment, the addition of DOM from the jellyfish induced a rapid growth of Pseudoalteromonas and Vibrio species that were isolated. After 9 days, the bacterial community was dominated by Bacteroidetes, which appeared more adapted to metabolize high-molecular-weight DOM. At the end of the experiment, the bacterial community shifted toward a higher proportion of Alphaproteobacteria. Resilience of the bacterial community after the addition of DOM from the jellyfish was higher for metabolic functions than diversity, suggesting that jellyfish blooms can induce durable changes in the bacterial community structure in coastal lagoons. PMID:25408076

Blanchet, Marine; Pringault, Olivier; Bouvy, Marc; Catala, Philippe; Oriol, Louise; Caparros, Jocelyne; Ortega-Retuerta, Eva; Intertaglia, Laurent; West, Nyree; Agis, Martin; Got, Patrice; Joux, Fabien

2014-11-20

331

Jellyfish Support High Energy Intake of Leatherback Sea Turtles (Dermochelys coriacea): Video Evidence from Animal-Borne Cameras  

PubMed Central

The endangered leatherback turtle is a large, highly migratory marine predator that inexplicably relies upon a diet of low-energy gelatinous zooplankton. The location of these prey may be predictable at large oceanographic scales, given that leatherback turtles perform long distance migrations (1000s of km) from nesting beaches to high latitude foraging grounds. However, little is known about the profitability of this migration and foraging strategy. We used GPS location data and video from animal-borne cameras to examine how prey characteristics (i.e., prey size, prey type, prey encounter rate) correlate with the daytime foraging behavior of leatherbacks (n?=?19) in shelf waters off Cape Breton Island, NS, Canada, during August and September. Video was recorded continuously, averaged 1:53 h per turtle (range 0:08–3:38 h), and documented a total of 601 prey captures. Lion's mane jellyfish (Cyanea capillata) was the dominant prey (83–100%), but moon jellyfish (Aurelia aurita) were also consumed. Turtles approached and attacked most jellyfish within the camera's field of view and appeared to consume prey completely. There was no significant relationship between encounter rate and dive duration (p?=?0.74, linear mixed-effects models). Handling time increased with prey size regardless of prey species (p?=?0.0001). Estimates of energy intake averaged 66,018 kJ•d?1 but were as high as 167,797 kJ•d?1 corresponding to turtles consuming an average of 330 kg wet mass•d?1 (up to 840 kg•d?1) or approximately 261 (up to 664) jellyfish•d-1. Assuming our turtles averaged 455 kg body mass, they consumed an average of 73% of their body mass•d?1 equating to an average energy intake of 3–7 times their daily metabolic requirements, depending on estimates used. This study provides evidence that feeding tactics used by leatherbacks in Atlantic Canadian waters are highly profitable and our results are consistent with estimates of mass gain prior to southward migration. PMID:22438906

Heaslip, Susan G.; Iverson, Sara J.; Bowen, W. Don; James, Michael C.

2012-01-01

332

Jellyfish support high energy intake of leatherback sea turtles (Dermochelys coriacea): video evidence from animal-borne cameras.  

PubMed

The endangered leatherback turtle is a large, highly migratory marine predator that inexplicably relies upon a diet of low-energy gelatinous zooplankton. The location of these prey may be predictable at large oceanographic scales, given that leatherback turtles perform long distance migrations (1000s of km) from nesting beaches to high latitude foraging grounds. However, little is known about the profitability of this migration and foraging strategy. We used GPS location data and video from animal-borne cameras to examine how prey characteristics (i.e., prey size, prey type, prey encounter rate) correlate with the daytime foraging behavior of leatherbacks (n = 19) in shelf waters off Cape Breton Island, NS, Canada, during August and September. Video was recorded continuously, averaged 1:53 h per turtle (range 0:08-3:38 h), and documented a total of 601 prey captures. Lion's mane jellyfish (Cyanea capillata) was the dominant prey (83-100%), but moon jellyfish (Aurelia aurita) were also consumed. Turtles approached and attacked most jellyfish within the camera's field of view and appeared to consume prey completely. There was no significant relationship between encounter rate and dive duration (p = 0.74, linear mixed-effects models). Handling time increased with prey size regardless of prey species (p = 0.0001). Estimates of energy intake averaged 66,018 kJ • d(-1) but were as high as 167,797 kJ • d(-1) corresponding to turtles consuming an average of 330 kg wet mass • d(-1) (up to 840 kg • d(-1)) or approximately 261 (up to 664) jellyfish • d(-1). Assuming our turtles averaged 455 kg body mass, they consumed an average of 73% of their body mass • d(-1) equating to an average energy intake of 3-7 times their daily metabolic requirements, depending on estimates used. This study provides evidence that feeding tactics used by leatherbacks in Atlantic Canadian waters are highly profitable and our results are consistent with estimates of mass gain prior to southward migration. PMID:22438906

Heaslip, Susan G; Iverson, Sara J; Bowen, W Don; James, Michael C

2012-01-01

333

Recombinant expression and solution structure of antimicrobial peptide aurelin from jellyfish Aurelia aurita  

SciTech Connect

Highlights: Black-Right-Pointing-Pointer Aurelin was overexpressed in Escherichia coli, and its spatial structure was studied by NMR. Black-Right-Pointing-Pointer Aurelin compact structure encloses helical regions cross-linked by three disulfide bonds. Black-Right-Pointing-Pointer Aurelin shows structural homology to the BgK and ShK toxins of sea anemones. Black-Right-Pointing-Pointer Aurelin binds to the anionic lipid vesicles, but does not interact with zwitterionic ones. Black-Right-Pointing-Pointer Aurelin binds to DPC micelle surface with moderate affinity via two helical regions. -- Abstract: Aurelin is a 40-residue cationic antimicrobial peptide isolated from the mezoglea of a scyphoid jellyfish Aurelia aurita. Aurelin and its {sup 15}N-labeled analogue were overexpressed in Escherichia coli and purified. Antimicrobial activity of the recombinant peptide was examined, and its spatial structure was studied by NMR spectroscopy. Aurelin represents a compact globule, enclosing one 3{sub 10}-helix and two {alpha}-helical regions cross-linked by three disulfide bonds. The peptide binds to anionic lipid (POPC/DOPG, 3:1) vesicles even at physiological salt concentration, it does not interact with zwitterionic (POPC) vesicles and interacts with the DPC micelle surface with moderate affinity via two {alpha}-helical regions. Although aurelin shows structural homology to the BgK and ShK toxins of sea anemones, its surface does not possess the 'functional dyad' required for the high-affinity interaction with the K{sup +}-channels. The obtained data permit to correlate the modest antibacterial properties and membrane activity of aurelin.

Shenkarev, Zakhar O.; Panteleev, Pavel V.; Balandin, Sergey V. [Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya str., 16/10, 117997 Moscow (Russian Federation)] [Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya str., 16/10, 117997 Moscow (Russian Federation); Gizatullina, Albina K.; Altukhov, Dmitry A. [Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya str., 16/10, 117997 Moscow (Russian Federation) [Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya str., 16/10, 117997 Moscow (Russian Federation); Moscow Institute of Physics and Technology (State University), Department of Physicochemical Biology and Biotechnology, Institutskii per., 9, 141700 Dolgoprudny, Moscow Region (Russian Federation); Finkina, Ekaterina I. [Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya str., 16/10, 117997 Moscow (Russian Federation)] [Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya str., 16/10, 117997 Moscow (Russian Federation); Kokryakov, Vladimir N. [Institute of Experimental Medicine, Russian Academy of Medical Sciences, Academica Pavlova str., 12, 197376 Saint-Petersburg (Russian Federation)] [Institute of Experimental Medicine, Russian Academy of Medical Sciences, Academica Pavlova str., 12, 197376 Saint-Petersburg (Russian Federation); Arseniev, Alexander S. [Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya str., 16/10, 117997 Moscow (Russian Federation) [Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya str., 16/10, 117997 Moscow (Russian Federation); Moscow Institute of Physics and Technology (State University), Department of Physicochemical Biology and Biotechnology, Institutskii per., 9, 141700 Dolgoprudny, Moscow Region (Russian Federation); Ovchinnikova, Tatiana V., E-mail: ovch@ibch.ru [Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya str., 16/10, 117997 Moscow (Russian Federation); Moscow Institute of Physics and Technology (State University), Department of Physicochemical Biology and Biotechnology, Institutskii per., 9, 141700 Dolgoprudny, Moscow Region (Russian Federation)

2012-12-07

334

Epidemiology of Jellyfish Stings Presented to an American Urban Emergency Department  

PubMed Central

Introduction Cnidarian, or jellyfifish, stings are a common malady in tropical Emergency Departments. There are limited studies examining cnidarian stings in the United States. The team investigated the epidemiology and treatments for jellyfish stings presenting to an urban emergency department (ED) in Honolulu, Hawai‘i. Methods The team performed a retrospective chart analysis of stings presented between 2000 and 2008. A total of 116 patients were identified. Charts were reviewed for patient demographics, incident characteristics, patient arrival condition, and treatments given in the emergency department. Results The median age was 24 years (range 9–85). Of patients 58% were men, 64% were Hawai‘i non-residents, and 23 % arrived between the hours of 10pm and 2 am. Emergency Medical System transported 64%, and 65% arrived with normal vital signs. Twenty-four different types of IV/PO medications were administered and patients received up to 5 different medications per visit. Intravenous medications were given to 64%. All patients were eventually discharged home from the ED. Discussion Risk factors for cnidarian stings include being men, being a Hawai‘i non-resident, and nighttime ocean activities. Stings were treated with various medications and routes suggesting that there is no current standard of care for stings. This study suggests that there is a need for public health interventions tailored to tourists. Prevention and education of home treatment could decrease the cost of health care by decreasing ambulance transports and total number of ED visits for a non-urgent disease. PMID:22162597

Onizuka, Neil

2011-01-01

335

Setting the Pace: New Insights into Central Pattern Generator Interactions in Box Jellyfish Swimming  

PubMed Central

Central Pattern Generators (CPGs) produce rhythmic behaviour across all animal phyla. Cnidarians, which have a radially symmetric nervous system and pacemaker centres in multiples of four, provide an interesting comparison to bilaterian animals for studying the coordination between CPGs. The box jellyfish Tripedalia cystophora is remarkable among cnidarians due to its most elaborate visual system. Together with their ability to actively swim and steer, they use their visual system for multiple types of behaviour. The four swim CPGs are directly regulated by visual input. In this study, we addressed the question of how the four pacemaker centres of this radial symmetric cnidarian interact. We based our investigation on high speed camera observations of the timing of swim pulses of tethered animals (Tripedalia cystophora) with one or four rhopalia, under different simple light regimes. Additionally, we developed a numerical model of pacemaker interactions based on the inter pulse interval distribution of animals with one rhopalium. We showed that the model with fully resetting coupling and hyperpolarization of the pacemaker potential below baseline fitted the experimental data best. Moreover, the model of four swim pacemakers alone underscored the proportion of long inter pulse intervals (IPIs) considerably. Both in terms of the long IPIs as well as the overall swim pulse distribution, the simulation of two CPGs provided a better fit than that of four. We therefore suggest additional sources of pacemaker control than just visual input. We provide guidelines for future research on the physiological linkage of the cubozoan CPGs and show the insight from bilaterian CPG research, which show that pacemakers have to be studied in their bodily and nervous environment to capture all their functional features, are also manifest in cnidarians. PMID:22073288

Stöckl, Anna Lisa; Petie, Ronald; Nilsson, Dan-Eric

2011-01-01

336

Jellyfish Lake, Palau: Regeneration of C, N, Si, and P in anoxic marine lake sediments  

USGS Publications Warehouse

Sediment cores from Jellyfish Lake were processed under an inert atmosphere and the pore waters extracted and analyzed for the following parameters: pH, titration alkalinity (TA), Cl-, H4SiO4, PO43-, NH4+, Ca2-, Mg2+, SO42-, and H2S. Additionally, in one set of pore-water samples (core 10), the ??13C of the ??CO2 was also determined. The TA, H4SiO4, PO43-, NH4+, and H2S increased with depth in the pore waters above anoxic bottom-water values. H2S values increased to 3.8 ??M. In one case, both H4SiO4 and PO43- concentrations increased to a maximum value and then decreased with depth, suggesting removal into solid phases. The H4SiO4 concentrations are equal to or greater than pore-water values observed in sediments underlying upwelling areas. PO43- concentrations are, in general, lower than pore-water values from terrigenous nearshore areas but higher than nearshore carbonate pore-water values from Florida Bay or Bermuda. The Ca2+, Cl-, and Mg2+: Cl- ratios show slight decreases in the top 15-20 cm, suggesting that authigenic carbonate may be forming. This suggestion is supported by the fact that the pore waters are saturated with respect to CaCO3 due to the very high TAs. The ??13C measurements of the pore-water ??CO2 are from a shorter core. These measurements reach their most negative concentration at 72 cm and then become slightly heavier. This change is accompanied by a decrease in TA, suggesting the onset of methanogenesis at this location in this core.

Lyons, W.B.; Lent, R.M.; Burnett, W.C.; Chin, P.; Landing, W.M.; Orem, W.H.; McArthur, J.M.

1996-01-01

337

[Molecular identification and detection of moon jellyfish (Aurelia sp.) based on partial sequencing of mitochondrial 16S rDNA and COI].  

PubMed

Taking the moon jellyfish Aurelia sp. commonly found in our coastal sea areas as test object, its genome DNA was extracted, the partial sequences of mt-16S rDNA (650 bp) and mt-COI (709 bp) were PCR-amplified, and, after purification, cloning, and sequencing, the sequences obtained were BLASTn-analyzed. The sequences of greater difference with those of the other jellyfish were chosen, and eight specific primers for the mt-16S rDNA and mt-COI of Aurelia sp. were designed, respectively. The specificity test indicated that the primer AS3 for the mt-16S rDNA and the primer AC3 for the mt-COI were excellent in rapidly detecting the target jellyfish from Rhopilema esculentum, Nemopilema nomurai, Cyanea nozakii, Acromitus sp., and Aurelia sp., and thus, the techniques for the molecular identification and detection of moon jellyfish were preliminarily established, which could get rid of the limitations in classical morphological identification of Aurelia sp. , being able to find the Aurelia sp. in the samples more quickly and accurately. PMID:23755504

Wang, Jian-Yan; Zhen, Yu; Wang, Guo-shan; Mi, Tie-Zhu; Yu, Zhi-gang

2013-03-01

338

Screening of extraction methods for glycoproteins from jellyfish ( Rhopilema esculentum) oral-arms by high performance liquid chromatography  

NASA Astrophysics Data System (ADS)

In order to select an optimum extraction method for the target glycoprotein (TGP) from jellyfish ( Rhopilema esculentum) oral-arms, a high performance liquid chromatography (HPLC)-assay for the determination of the TGP was developed. Purified target glycoprotein was taken as a standard glycoprotein. The results showed that the calibration curves for peak area plotted against concentration for TGP were linear ( r = 0.9984, y = 4.5895 x+47.601) over concentrations ranging from 50 to 400 mgL-1. The mean extraction recovery was 97.84% (CV2.60%). The fractions containing TGP were isolated from jellyfish ( R. esculentum) oral-arms by four extraction methods: 1) water extraction (WE), 2) phosphate buffer solution (PBS) extraction (PE), 3) ultrasound-assisted water extraction (UA-WE), 4) ultrasound-assisted PBS extraction (UA-PE). The lyophilized extract was dissolved in Milli-Q water and analyzed directly on a short TSK-GEL G4000PWXL (7.8 mm×300 mm) column. Our results indicated that the UA-PE method was the optimum extraction method selected by HPLC.

Ren, Guoyan; Li, Bafang; Zhao, Xue; Zhuang, Yongliang; Yan, Mingyan; Hou, Hu; Zhang, Xiukun; Chen, Li

2009-03-01

339

Nitrogen and phosphorus budget of a polyculture system of sea cucumber ( Apostichopus japonicus), jellyfish ( Rhopilema esculenta) and shrimp ( Fenneropenaeus chinensis)  

NASA Astrophysics Data System (ADS)

The nitrogen (N) and phosphorus (P) budget and the ecological efficiency of a polyculture system of sea cucumber ( Apostichopus japonicus), jellyfish ( Rhopilema esculenta) and shrimp ( Fenneropenaeus chinensis) were studied in a cofferdam, 120.2 ha in size. The nutrients were supplied by spring tide inflow. In total, 139600 kg N yr-1 and 9730 kg P yr-1 input to the system; while 118900 kg N yr-1 and 2840 kg P yr-1 outflowed from the system concurrently, thus the outflow was 85.7% (N) and 29.2% (P) of inflow. The production of N and P was 889.5 kg yr-1 and 49.28 kg yr-1 (sea cucumber) and 204 kg yr-1 and 18.03 kg yr-1 (jellyfish and shrimp), respectively. The utilization rate of N and P by polycultured animals was 7.8‰ and 6.9‰, respectively, 21.9% and 38% higher than that of monocultured sea cucumber. Our results indicated that the polyculture system was an efficient culture system of animals and a remediation system of coastal environment as well; it scavenged 14.3% and 70.8% of N and P, respectively. Such an ecological efficiency may be improved further by increasing either the stocking density or the size of sea cucumber or both.

Li, Junwei; Dong, Shuanglin; Gao, Qinfeng; Zhu, Changbo

2014-06-01

340

Abrupt Changes in the Marmara Pelagic Ecosystem during the recent jellyfish Liriope tetraphylla invasion and mucilage events  

NASA Astrophysics Data System (ADS)

In this study, meteorological and hydrographical conditions as well as chemical and biological parameters have been examined for the period 2005-2009 to determine the impact and cause of the massive mucilage phenomenon observed in the Sea of Marmara in October 2007. Results showed that there is a decrease pattern in chl concentration as well as both phytoplankton and zooplankton abundances from August till October in 2007 whilst the jellyfish Liriope tetraphylla had bloom levels. This period coincided with the maximum intensity of pelagic fishing throughout the years. Nitrogen/phosphate ratio increased prior to the mucilage formation. Invasive Liriope tetraphylla abundance increased exponentially in August and died in masses as a result of starvation and meteorological / oceanographic conditions. In October, following the mucilage matter production another new species for the region Gonyaulax fragilis was observed in high abundance through the basin. It is worthy to note that during basin wide samplings conducted in the Sea of Marmara in both 2005 and 2006, high abundances of Liriope tetraphylla have been detected particularly at the northern parts where no mucilage event was observed. We suggest that overfishing in the Sea of Marmara provided a ground for the establishment of the invasive jellyfish and accompanying mucilage event was due to by synergic combinations of several factors.

Erkan Kideys, Ahmet; Yüksek, Ahsen; Sur, Halil Ibrahim

2013-04-01

341

New family of allomorphic jellyfishes, Drymonematidae (Scyphozoa, Discomedusae), emphasizes evolution in the functional morphology and trophic ecology of gelatinous zooplankton.  

PubMed

Molecular analyses have revealed many cryptic species in the oceans, often permitting small morphological differences to be recognized as diagnosing species, but less commonly leading to consideration of cryptic ecology. Here, based on analyses of three nuclear DNA sequence markers (ribosomal 18S, 28S, and internal transcribed spacer 1 [ITS1]), two mitochondrial DNA markers (cytochrome c oxidase subunit I [COI] and ribosomal 16S), and 55 morphological features, we revise the classification of the enigmatic jellyfish genus Drymonema. We describe a new scyphozoan family, Drymonematidae, elevating the previous subfamily Drymonemidae to accommodate three species: the type species D. dalmatinum from the Mediterranean region, for which we identify a neotype; the western South Atlantic species D. gorgo; and a new species, D. larsoni from the western Atlantic and Caribbean, which also is described here. This revision emphasizes the remarkable morphological disparity of Drymonematidae from all other scyphomedusae, including allometric growth of the bell margin distal of the rhopalia, an annular zone of tentacles on the subumbrella, and ontogenetic loss of gastric filaments. Anatomical innovations are likely functionally related to predatory specialization on large gelatinous zooplankton, most notably the phylogenetically younger moon jellyfish Aurelia, indicating evolution of the feeding niche in Drymonematidae. This family-level revision contributes to the growing body of evidence that scyphomedusae are far more taxonomically rich, their biogeography is a more detailed mosaic, and their phenotypes are more nuanced than traditionally thought. Ecological and evolutionary responses to environmental change, past or future, are likely to be commensurately diverse. PMID:21183445

Bayha, Keith M; Dawson, Michael N

2010-12-01

342

The Acute Toxicity and Hematological Characterization of the Effects of Tentacle-Only Extract from the Jellyfish Cyanea capillata  

PubMed Central

To investigate the hematologic changes and the activities of jellyfish venoms other than hemolytic and cardiovascular toxicities, the acute toxicity of tentacle-only extract (TOE) from the jellyfish Cyanea capillata was observed in mice, and hematological indexes were examined in rats. The median lethal dose (LD50) of TOE was 4.25 mg/kg, and the acute toxicity involved both heart- and nervous system-related symptoms. Arterial blood gas indexes, including pH, PCO2, HCO3?, HCO3std, TCO2, BEecf and BE (B), decreased significantly. PO2 showed a slight increase, while SO2c (%) had no change at any time. Na+ and Ca2+ decreased, but K+ increased. Biochemical indexes, including LDH, CK, CK-MB, ALT, AST and sCr, significantly increased. Other biochemical indexes, including BUN and hemodiastase, remained normal. Lactic acid significantly increased, while glucose, Hct% and THbc showed slight temporary increases and then returned to normal. These results on the acute toxicity and hematological changes should improve our understanding of the in vivo pathophysiological effects of TOE from C. capillata and indicate that it may also have neurotoxicity, liver toxicity and muscular toxicity in addition to hemolytic and cardiovascular toxicities, but no kidney or pancreatic toxicity. PMID:21731547

Xiao, Liang; Liu, Sihua; He, Qian; Wang, Qianqian; Ye, Xuting; Liu, Guoyan; Nie, Fei; Zhao, Jie; Zhang, Liming

2011-01-01

343

Cardiovascular Effect Is Independent of Hemolytic Toxicity of Tentacle-Only Extract from the Jellyfish Cyanea capillata  

PubMed Central

Our previous studies have confirmed that the crude tentacle-only extract (cTOE) from the jellyfish Cyanea capillata (Cyaneidae) exhibits hemolytic and cardiovascular toxicities simultaneously. So, it is quite difficult to discern the underlying active component responsible for heart injury caused by cTOE. The inactivation of the hemolytic toxicity from cTOE accompanied with a removal of plenty of precipitates would facilitate the separation of cardiovascular component and the investigation of its cardiovascular injury mechanism. In our research, after the treatment of one-step alkaline denaturation followed by twice dialysis, the protein concentration of the treated tentacle-only extract (tTOE) was about 1/3 of cTOE, and SDS-PAGE showed smaller numbers and lower density of protein bands in tTOE. The hemolytic toxicity of tTOE was completely lost while its cardiovascular toxicity was well retained. The observations of cardiac function, histopathology and ultrastructural pathology all support tTOE with significant cardiovascular toxicity. Blood gas indexes and electrolytes changed far less by tTOE than those by cTOE, though still with significant difference from normal. In summary, the cardiovascular toxicity of cTOE can exist independently of the hemolytic toxicity and tTOE can be employed as a better venom sample for further purification and mechanism research on the jellyfish cardiovascular toxic proteins. PMID:22905209

Qianqian, Wang; Sihua, Liu; Yang, Wang; Guoyan, Liu; Jia, Lu; Xuting, Ye; Liming, Zhang

2012-01-01

344

Lipid Peroxidation Is another Potential Mechanism besides Pore-Formation Underlying Hemolysis of Tentacle Extract from the Jellyfish Cyanea capillata  

PubMed Central

This study was performed to explore other potential mechanisms underlying hemolysis in addition to pore-formation of tentacle extract (TE) from the jellyfish Cyanea capillata. A dose-dependent increase of hemolysis was observed in rat erythrocyte suspensions and the hemolytic activity of TE was enhanced in the presence of Ca2+, which was attenuated by Ca2+ channel blockers (Diltiazem, Verapamil and Nifedipine). Direct intracellular Ca2+ increase was observed after TE treatment by confocal laser scanning microscopy, and the Ca2+ increase could be depressed by Diltiazem. The osmotic protectant polyethylenglycol (PEG) significantly blocked hemolysis with a molecular mass exceeding 4000 Da. These results support a pore-forming mechanism of TE in the erythrocyte membrane, which is consistent with previous studies by us and other groups. The concentration of malondialdehyde (MDA), an important marker of lipid peroxidation, increased dose-dependently in rat erythrocytes after TE treatment, while in vitro hemolysis of TE was inhibited by the antioxidants ascorbic acid—Vitamin C (Vc)—and reduced glutathione (GSH). Furthermore, in vivo hemolysis and electrolyte change after TE administration could be partly recovered by Vc. These results indicate that lipid peroxidation is another potential mechanism besides pore-formation underlying the hemolysis of TE, and both Ca2+ channel blockers and antioxidants could be useful candidates against the hemolytic activity of jellyfish venoms. PMID:23303301

Wang, Tao; Wen, Xiao-Juan; Mei, Xiao-Bin; Wang, Qian-Qian; He, Qian; Zheng, Jie-Min; Zhao, Jie; Xiao, Liang; Zhang, Li-Ming

2013-01-01

345

Antihypertensive Effect of Long-Term Oral Administration of Jellyfish (Rhopilema esculentum) Collagen Peptides on Renovascular Hypertension  

PubMed Central

Antihypertensive effect of long-term oral administration of jellyfish (Rhopilema esculentum) collagen peptides (JCP) on renovascular hypertension rats (RVHs) was evaluated. The systolic blood pressure and diastolic blood pressure of the RVHs were significantly reduced with administration of JCP (p < 0.05), compared with model control group. However, the arterial blood pressure of normal rats showed no significant changes during long-term oral treatment with high dose JCP (p > 0.05). Furthermore, effect of JCP on angiotensin II (Ang II) concentration of plasma had no significance (p > 0.05), but JCP significantly inhibited the Ang II concentration in RVHs’ kidney (p < 0.05). The kidney should be the target site of JCP. PMID:22412809

Zhuang, Yongliang; Sun, Liping; Zhang, Yufeng; Liu, Gaoxiang

2012-01-01

346

Antihypertensive effect of long-term oral administration of jellyfish (Rhopilema esculentum) collagen peptides on renovascular hypertension.  

PubMed

Antihypertensive effect of long-term oral administration of jellyfish (Rhopilema esculentum) collagen peptides (JCP) on renovascular hypertension rats (RVHs) was evaluated. The systolic blood pressure and diastolic blood pressure of the RVHs were significantly reduced with administration of JCP (p < 0.05), compared with model control group. However, the arterial blood pressure of normal rats showed no significant changes during long-term oral treatment with high dose JCP (p > 0.05). Furthermore, effect of JCP on angiotensin II (Ang II) concentration of plasma had no significance (p > 0.05), but JCP significantly inhibited the Ang II concentration in RVHs' kidney (p < 0.05). The kidney should be the target site of JCP. PMID:22412809

Zhuang, Yongliang; Sun, Liping; Zhang, Yufeng; Liu, Gaoxiang

2012-02-01

347

Effects of collagen and collagen hydrolysate from jellyfish (Rhopilema esculentum) on mice skin photoaging induced by UV irradiation.  

PubMed

Collagen (JC) was extracted from jellyfish (Rhopilema esculentum) and hydrolyzed to prepare collagen hydrolysate (JCH). The protective effects of JC and JCH against UV-induced damages to mice skin were evaluated and compared in this article. JC and JCH could alleviate the UV-induced abnormal changes of antioxidative indicators, including the superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) activities and the contents of glutathione (GSH) and malondiaidehyde (MDA). JC and JCH could protect skin lipid and collagen from the UV radiation damages. Furthermore, the changes of total ceramide and glycosaminoglycan in skin were recovered significantly by JC and JCH. The action mechanisms mainly involved the antioxidative properties and the repairing to endogenous collagen synthesis of JC and JCH in vivo. JCH with the lower molecular weight showed much higher effects than JC. The results indicated that JCH was a novel antiphotoaging agent from natural resources. PMID:19723203

Zhuang, Yongliang; Hou, Hu; Zhao, Xue; Zhang, Zhaohui; Li, Bafang

2009-08-01

348

Noninvasive laser therapy in the treatment of keloid scar after injury caused by a jellyfish: a case report  

NASA Astrophysics Data System (ADS)

Keloid scars trouble the patients particularly for aesthetical reasons. They also frequency result in various functional disturbances, they are painful and the patient suffers for dysesthesia on touch. Low level laser is able to provide three principal effects: biostimulating, analgesic and antiinflammatory. Particularly thanks to the first two effects we are able, when adhering to the proper therapeutic procedure, to moderate or even remove the above mentioned problems. We complement the low level laser treatment by applications of ointments, cremes or silicone strips. Our communication is aimed at a case report concerning the treatment of keloid scars resulting from an injury by a jellyfish with the aim to familiarize the reader with wide therapeutic possibilities of non-invasive laser, even in indications which are not frequently encountered in central Europe.

Kymplova, Jaroslava; Navratil, Leos; Skopek, Jiri

2001-10-01

349

Settlement of planulae of the Moon jellyfish Aurelia aurita onto hydrophilic polycarbonate plates modified by atmospheric plasma treatment.  

PubMed

It has been reported that planula larvae of some jellyfish prefer artificial substrates for settlement. This research focused on the relationship between the settlement of planulae and the wettability of artificial substrate surfaces. We used atmospheric plasmas to change the wettability of the surfaces of polycarbonate (PC) plates because plasma treatment has no chemical side effects. The treatment made the surfaces hydrophilic, as evidenced by the decrease of contact angle from 85° to 35°. X-ray photoelectron spectroscopy revealed that the change of wettability of the PC plates could be attributed to N2, which was probably ionized in the air above the plates. Scanning electron microscopy revealed no difference in the surface morphology of the plates before and after plasma treatment. Results of bioassays using treated PC plates showed that planulae tended to preferentially settle on hydrophobic surfaces. PMID:24465603

Tomaru, Akiko; Sasaki, Ryota; Miyahara, Hidekazu; Okino, Akitoshi; Ogawa, Nobuhiro; Hamasaki, Koji

2014-01-01

350

Lipid Peroxidation Is another Potential Mechanism besides Pore-Formation Underlying Hemolysis of Tentacle Extract from the Jellyfish Cyanea capillata  

E-print Network

Abstract: This study was performed to explore other potential mechanisms underlying hemolysis in addition to pore-formation of tentacle extract (TE) from the jellyfish Cyanea capillata. A dose-dependent increase of hemolysis was observed in rat erythrocyte suspensions and the hemolytic activity of TE was enhanced in the presence of Ca 2+, which was attenuated by Ca 2+ channel blockers (Diltiazem, Verapamil and Nifedipine). Direct intracellular Ca 2+ increase was observed after TE treatment by confocal laser scanning microscopy, and the Ca 2+ increase could be depressed by Diltiazem. The osmotic protectant polyethylenglycol (PEG) significantly blocked hemolysis with a molecular mass exceeding 4000 Da. These results support a pore-forming mechanism of TE in the erythrocyte membrane, which is consistent with previous studies by us and other groups. The concentration of malondialdehyde (MDA), an important marker of lipid peroxidation, increased dose-dependently in rat erythrocytes after TE treatment, while in vitro hemolysisMar. Drugs 2013, 11 68

Tao Wang; Xiao-juan Wen; Xiao-bin Mei; Qian-qian Wang; Qian He; Jie-min Zheng; Jie Zhao; Liang Xiao; Li-ming Zhang

2013-01-01

351

First Evidence of Inbreeding, Relatedness and Chaotic Genetic Patchiness in the Holoplanktonic Jellyfish Pelagia noctiluca (Scyphozoa, Cnidaria)  

PubMed Central

Genetic drift and non-random mating seldom influence species with large breeding populations and high dispersal potential, characterized by unstructured gene pool and panmixia at a scale lower than the minimum dispersal range of individuals. In the present study, a set of nine microsatellite markers was developed and used to investigate the spatio-temporal genetic patterns of the holoplanktonic jellyfish Pelagia noctiluca (Scyphozoa) in the Southern Tyrrhenian Sea. Homozygote excess was detected at eight loci, and individuals exhibited intra-population relatedness higher than expected by chance in at least three samples. This result was supported by the presence of siblings in at least 5 out 8 samples, 4 of which contained full-sib in addition to half-sib dyads. Having tested and ruled out alternative explanations as null alleles, our results suggest the influence of reproductive and behavioural features in shaping the genetic structure of P. noctiluca, as outcomes of population genetics analyses pointed out. Indeed, the genetic differentiation among populations was globally small but highlighted: a) a spatial genetic patchiness uncorrelated with distance between sampling locations, and b) a significant genetic heterogeneity between samples collected in the same locations in different years. Therefore, despite its extreme dispersal potential, P. noctiluca does not maintain a single homogenous population, but rather these jellyfish appear to have intra-bloom localized recruitment and/or individual cohesiveness, whereby siblings more likely swarm together as a single group and remain close after spawning events. These findings provide the first evidence of family structures and consequent genetic patchiness in a species with highly dispersive potential throughout its whole life cycle, contributing to understanding the patterns of dispersal and connectivity in marine environments. PMID:24977703

Aglieri, Giorgio; Papetti, Chiara; Zane, Lorenzo; Milisenda, Giacomo; Boero, Ferdinando; Piraino, Stefano

2014-01-01

352

A numerical study of the effects of bell pulsation dynamics and oral arms on the exchange currents generated by the upside-down jellyfish Cassiopea spp  

E-print Network

Mathematical and experimental studies of the flows generated by jellyfish have focused primarily on mechanisms of swimming. More recent work has also considered the fluid dynamics of feeding from currents generated during swimming. Here the benthic lifestyle of the upside down jellyfish (Cassiopea spp.) is capitalized upon to explore the fluids dynamics of feeding uncoupled from swimming. A mathematical model is developed to capture the fundamental characteristics of the motion of the unique concave bell shape. Given the prominence of the oral arms, this structure is included and modeled as a porous layer that perturbs the flow generated by bell contractions. The immersed boundary method is used to solve the fluid-structure interaction problem. Velocity fields obtained from live organisms using digital particle image velocimetry were used to validate the numerical simulations. Parameter sweeps were used to numerically explore the effects of changes in pulse dynamics and the properties of the oral arms indepen...

Hamlet, Christina; Miller, Laura A

2010-01-01

353

Ontogeny of anti-predator behavior in hatchery-reared jack mackerel Trachurus japonicus larvae and juveniles: patchiness formation, swimming capability, and interaction with jellyfish  

Microsoft Academic Search

Laboratory rearing and behavioral observations of larval and juvenile jack mackerel Trachurus japonicus were conducted to elucidate their life-history traits with emphasis on the interaction with the moon jellyfish Aurelia aurita. Jack mackerel were raised from naturally spawned fertilized eggs and they attained 10.3±0.7 (mean±standard deviation) mm\\u000a in body length (BL) by 30 days post hatching (dph) and 26.6±1.8 mm

Reiji Masuda

2006-01-01

354

Spatial distribution of the upside-down jellyfish Cassiopea sp. within fringing coral reef environments of the Northern Red Sea: implications for its life cycle  

Microsoft Academic Search

The zooxanthellate mangrove jellyfish Cassiopea sp. represents a prominent invasive species and a potential bioindicator for nutrient monitoring in coral reefs. However,\\u000a information about its spatial distribution in combination with abundance, habitat specificity and life cycle elements is barely\\u000a available. This study, therefore, presents the results of field surveys conducted within four different benthic habitat types\\u000a (coral reef, seagrass meadow,

Wolfgang Niggl; Christian Wild

2010-01-01

355

First Report of a Peroxiredoxin Homologue in Jellyfish: Molecular Cloning, Expression and Functional Characterization of CcPrx4 from Cyanea capillata  

PubMed Central

We first identified and characterized a novel peroxiredoxin (Prx), designated as CcPrx4, from the cDNA library of the tentacle of the jellyfish Cyanea capillata. The full-length cDNA sequence of CcPrx4 consisted of 884 nucleotides with an open reading frame encoding a mature protein of 247 amino acids. It showed a significant homology to peroxiredoxin 4 (Prx4) with the highly conserved F-motif (93FTFVCPTEI101), hydrophobic region (217VCPAGW222), 140GGLG143 and 239YF240, indicating that it should be a new member of the Prx4 family. The deduced CcPrx4 protein had a calculated molecular mass of 27.2 kDa and an estimated isoelectric point of 6.3. Quantitative real-time PCR analysis showed that CcPrx4 mRNA could be detected in all the jellyfish tissues analyzed. CcPrx4 protein was cloned into the expression vector, pET-24a, and expressed in Escherichia coli Rosetta (DE3) pLysS. Recombinant CcPrx4 protein was purified by HisTrap High Performance chelating column chromatography and analyzed for its biological function. The results showed that the purified recombinant CcPrx4 protein manifested the ability to reduce hydrogen peroxide and protect supercoiled DNA from oxidative damage, suggesting that CcPrx4 protein may play an important role in protecting jellyfish from oxidative damage. PMID:24413803

Ruan, Zengliang; Liu, Guoyan; Wang, Beilei; Zhou, Yonghong; Lu, Jia; Wang, Qianqian; Zhao, Jie; Zhang, Liming

2014-01-01

356

The medical zoologist--Ronald Vernon Southcott.  

PubMed

Dr Ronald Vernon Southcott (1918-1998) was amongst the greatest of the Australian doctor-naturalists. His toxinological contributions included the description and naming of the box-jellyfish, Chironex fleckeri, the first definitive study (1950-1957) of the toxinology, taxonomy and biology of Australian scorpions; and the first observations in Australia of the introduced fiddleback spider, Loxosceles. His research into the medical effects of toxic fungi, poisonous plants and Australian insects was extensive. He was a founding member of the International Society on Toxinology and served on the Toxicon Editorial Board for more than 30 years. He also made extensive contributions to acarology, and to the taxonomy of mites, specifically the sub-families and genera of the Erythraeoidea. This prodigious output was achieved by one who, with the exception of war service (1942-1946), almost never travelled outside South Australia, was almost entirely self-funded and worked from his home laboratory. With Dr. P.D. Scott and C.J. Glover, he was also the authority on the fish of South Australia. Dr. Southcott was also a medical epidemiologist and senior medical administrator (1949-1978) with the Australian Commonwealth Department of Veterans' Affairs. He served for 30 years as an Honorary Consultant in Toxicology to the Adelaide Children's Hospital. As a zoologist and botanist of astounding breadth, he worked indefatigably in a voluntary capacity for the South Australian Museum, of which he was Museum Board Chairman from 1974 to 1982. In the pantheon of the great doctor-naturalists who have worked in Australia, he stands with Robert Brown and Thomas Lane Bancroft. PMID:16934849

Pearn, John

2006-12-01

357

Preliminary Results of the in Vivo and in Vitro Characterization of a Tentacle Venom Fraction from the Jellyfish Aurelia aurita  

PubMed Central

The neurotoxic effects produced by a tentacle venom extract and a fraction were analyzed and correlated by in vivo and in vitro approaches. The tentacle venom extract exhibited a wide range of protein components (from 24 to >225 kDa) and produced tetanic reactions, flaccid paralysis, and death when injected into crabs. Two chromatography fractions also produced uncontrolled appendix movements and leg stretching. Further electrophysiological characterization demonstrated that one of these fractions potently inhibited ACh-elicited currents mediated by both vertebrate fetal and adult muscle nicotinic acetylcholine receptors (nAChR) subtypes. Receptor inhibition was concentration-dependent and completely reversible. The calculated IC50 values were 1.77 ?g/?L for fetal and 2.28 ?g/?L for adult muscle nAChRs. The bioactive fraction was composed of a major protein component at ~90 kDa and lacked phospholipase A activity. This work represents the first insight into the interaction of jellyfish venom components and muscle nicotinic receptors. PMID:24322597

Ponce, Dalia; López-Vera, Estuardo; Aguilar, Manuel B.; Sánchez-Rodríguez, Judith

2013-01-01

358

Flow characteristics past jellyfish and St. Vincent valves in the aortic position under physiological pulsatile flow conditions.  

PubMed

Thrombus formation and hemolysis have been linked to the dynamic flow characteristics of heart valve prostheses. To enhance our understanding of the flow characteristics past the aortic position of a Jellyfish (JF) valve in the left ventricle, in vitro laser Doppler anemometry (LDA) measurements were carried out under physiological pulsatile flow conditions. The hemodynamic performance of the JF valve was then compared with that of the St. Vincent (SV) valve. The comparison was given in terms of mean systolic pressure drop, back flow energy losses, flow velocity, and shear stresses at various locations downstream of both valves and at cardiac outputs of 3.5 L/min, 4.5 L/min, and 6.5 L/min respectively. The results indicated that both valves created disturbed flow fields with elevated levels of turbulent shear stress as well as higher levels of turbulence in the immediate vicinity of the valve and up to 1 diameter of the pipe (D) downstream of the valve. At a location further downstream, the JF valve showed better flow characteristics than the SV in terms of velocity profiles and turbulent shear stresses. The closure volume of the SV valve was found to be 2.5 times higher than that of the JF valve. Moreover, the total back flow losses and mean systolic pressure drop also were found to be higher in the SV than the JF valve. PMID:10916068

Morsi, Y S; Sakhaeimanesh, A A

2000-07-01

359

Fine structure, histochemistry, and morphogenesis during excystment of the podocysts of the giant jellyfish Nemopilema nomurai (Scyphozoa, Rhizostomeae).  

PubMed

Production of podocysts is the exclusive form of asexual reproduction by polyps of the giant jellyfish Nemopilema nomurai, which has been recurrently blooming in the East Asian seas in the last decade. Podocycts consist of a dome-shaped chitinous capsule with laminated structure that encapsulates a mass of cyst cells filled with granules containing nutrient reserves such as proteins, carbohydrates, and lipids. Mitochondria, rough endoplasmic reticulum, and Golgi complexes are scarce in the cytoplasm of these cells, and the staining reaction for RNA is weak, indicating very low metabolic activity. Podocysts are capable of dormancy for at least 5 years without significant change of internal structure or nutrient reserves. Integrated information about spontaneous and artificially induced metamorphosis suggests that the following processes occur during excystment: (1) nematocyst formation in the internal cell mass, (2) stratification of the cell mass into endoderm and ectoderm, (3) extrusion of the cell mass through a gradual opening of the capsule, (4) formation of primordial polyp mouth and tentacles, and (5) metamorphosis to a polyp. We morphologically confirmed that N. nomurai podocysts have the capacity for long-term dormancy, an ability that should contribute to the periodic nature of the massive blooms of medusae of this species. PMID:22186913

Ikeda, Hideki; Ohtsu, Kohzoh; Uye, Shin-Ichi

2011-12-01

360

Density and sound speed of two gelatinous zooplankton: ctenophore (Mnemiopsis leidyi) and lion's mane jellyfish (Cyanea capillata).  

PubMed

The density and sound speed of two coastal, gelatinous zooplankton, Mnemiopsis leidyi (a ctenophore) and Cyanea capillata (lion's mane jellyfish), were measured. These parameters are important inputs to acoustic scattering models. Two different methods were used to measure the density of individual animals: one used a balance and graduated cylinder to determine the mass and displacement volume of the animal, the other varied the density of the solution the animal was immersed in. When the same animal was measured using both methods, density values were within 1% of each other. A travel-time difference method was used to measure the sound speed within the animals. The densities of both zooplankton slightly decreased as the animals increased in length, mass, and volume. The ratio of animal density and sound speed to the surrounding seawater (g and h, respectively) are reported for both animals. For Mnemiopsis leidyi ranging in length from 1 to 5 cm, the mean value (+/-standard deviation) of g and h were 1.009 (+/-0.004) and 1.007 (+/-0.001). For Cyanea capillata ranging in bell diameter from 2 to 11 cm, the mean value (+/-standard deviation) of g and single value of h were 1.009 (+/-0.004) and 1.0004. PMID:17614513

Warren, Joseph D; Smith, Joy N

2007-07-01

361

Behavior of the giant jellyfish Nemopilema nomurai in the East China Sea and East/Japan Sea during the summer of 2005: A numerical model approach using a particle-tracking experiment  

NASA Astrophysics Data System (ADS)

The contribution of physical processes in the distribution of the giant jellyfish Nemopilema nomurai in the northern East China (ECS) Yellow (YS) and East/Japan (EJS) seas in summer 2005 was simulated by a Lagrangian particle-tracking experiment based on ROMS (Regional Ocean Modeling System). The particles representing jellyfish were released in the western YS between the Shandong Peninsula and the Changjiang River mouth from May to July 2005, and then tracked. Particles released in May-June in the Changjiang mouth moved mostly east-northeastward to the Korea/Tsushima Strait, and thereafter they moved to the Tsugaru Strait along the west coast of Japan from summer to fall. About 80% of the particles entered the EJS in this period. However, most of the particles from the northern Changjiang distributed in the YS, drifting anticlockwise, and thus only about 13% of the total particles entered the EJS area. The particle-tracking analysis shows that the observed distributions of the giant jellyfish in the northern ECS and EJS are quite similar to those of particles driven by wind forcing and ambient along-shelf currents in this area. The results with and without wind conditions differ fundamentally. With wind forcing, the eastward summer movement of the particles was enhanced; this determined the spatial distribution pattern of the particles and jellyfish in the waters around the Korean Peninsula. Moreover the particle distribution over time strongly suggests the Changjiang mouth as one of the jellyfish seeding places. The results show that a particle-tracking experiment can be used to determine jellyfish drift and that wind forcing and along-shelf currents are the factors determining the distribution.

Moon, Jae-Hong; Pang, Ig-Chan; Yang, Joon-Yong; Yoon, Won Duk

2010-02-01

362

Spatiotemporal characteristics and mechanisms of intracellular Ca(2+) increases at fertilization in eggs of jellyfish (Phylum Cnidaria, Class Hydrozoa).  

PubMed

We have clarified, for the first time, the spatiotemporal patterns of intracellular Ca(2+) increases at fertilization and the Ca(2+)-mobilizing mechanisms in eggs of hydrozoan jellyfish, which belong to the evolutionarily old diploblastic phylum, Cnidaria. An initial Ca(2+) increase just after fertilization took the form of a Ca(2+) wave starting from one cortical region of the egg and propagating to its antipode in all of four hydrozoan species tested: Cytaeis uchidae, Cladonema pacificum, Clytia sp., and Gonionema vertens. The initiation site of the Ca(2+) wave was restricted to the animal pole, which is known to be the only area of sperm-egg fusion in hydrozoan eggs, and the wave propagating velocity was estimated to be 4.2-5.9 mum/s. After a Ca(2+) peak had been attained by the initial Ca(2+) wave, the elevated Ca(2+) gradually declined and returned nearly to the resting value at 7-10 min following fertilization. Injection of inositol 1,4,5-trisphosphate (IP(3)), an agonist of IP(3) receptors (IP(3)R), was highly effective in inducing a Ca(2+) increase in unfertilized eggs; IP(3) at a final intracellular concentration of 12-60 nM produced a fully propagating Ca(2+) wave equivalent to that observed at fertilization. In contrast, a higher concentration of cyclic ADP-ribose (cADPR), an agonist of ryanodine receptors (RyR), only generated a localized Ca(2+) increase that did not propagate in the egg. In addition, caffeine, another stimulator of RyR, was completely without effect. Sperm-induced Ca(2+) increases in Gonionema eggs were severely affected by preinjection of heparin, an inhibitor of Ca(2+) release from IP(3)R. These results strongly suggest that there is a well-developed IP(3)R-, but not RyR-mediated Ca(2+) release mechanism in hydrozoan eggs and that the former system primarily functions at fertilization. Our present data also demonstrate that the spatial characteristics and mechanisms of Ca(2+) increases at fertilization in hydrozoan eggs resemble those reported in higher triploblastic animals. PMID:15733659

Deguchi, Ryusaku; Kondoh, Eri; Itoh, Junko

2005-03-15

363

Impairment of the cell-to-matrix adhesion and cytotoxicity induced by the Mediterranean jellyfish Pelagia noctiluca venom and its fractions in cultured glioblastoma cells  

PubMed Central

Background The biodiversity of the marine environment and the associated chemical diversity constitute a practically unlimited source of new active substances in the field of the development of bioactive products. In our study, we have investigated the efficiency of the venom from the Mediterranean jellyfish, Pelagia noctiluca and its fractions for anti-proliferative and anti-cell adhesion to cell–extracellular matrix activities. Results Our experiments have indicated that the separation of the Mediterranean jellyfish Pelagia noctiluca crude venom extract by sephadex G-75 chromatography led to four fractions (F1, F2, F3, and F4). Among the four fractions F1 and F3 were cytotoxic against U87 cells with IC50 values of 125 and 179??g/ml respectively. The venom, F1, F2 and F 3 showed significant anti-proliferative activity in time-dependent manner. Our results also suggest that these fractions and the venom are able to inhibit cell adhesion to fibrinogen in dose-dependent manner. This inhibition is reliant on its ability to interact with integrins. Conclusions To conclude, we have demonstrated for the first time that Pelagia noctiluca venom and its fractions especially (F1 and F2) display potent anti-tumoral properties. Separation by sephadex G-75 chromatography give rise to more active fractions than the crude venom extract. The purification and the determination of chemical structures of compounds of these active fractions are under investigation. Overall, Pelagia noctiluca venom may has the potential to serve as a template for future anticancer-drug development. PMID:22741917

2012-01-01

364

Devin, Alligators, Jellyfish, and Me.  

ERIC Educational Resources Information Center

Describes how a first-grade teacher used the "hypothesis-test" approach with Devin, a first grader who struggled as a reader and writer. Points out that, when she started working with Devin, she wanted to understand his difficulties, but by the end, she realized that it was her curriculum, not his difficulties, that needed to be in the foreground.…

Tsuchiyama, Elaine

1997-01-01

365

Jellyfish: Networking Data Centers, Randomly  

E-print Network

Data centers today form the backbone of cloud operations. A well provisioned data center network is important to ensure that servers do not face bandwidth bottlenecks to utilization; to isolate services from each other;

Ankit Singla; Chi-yao Hong; Lucian Popa; P. Brighten Godfrey

366

A rapid and repeatable method for venom extraction from cubozoan nematocysts.  

PubMed

Various comparative studies into the biological activity and relative toxicity of cubozoan venoms have been investigated, in particular the venom from the potentially lethal cubozoan Chironex fleckeri. Efficient and reliable extraction of venom from nematocysts is essential before any research into venom toxicity can be conducted and previous cited methods of extraction have varied greatly, each with their own associated problems. A new standardised technique for the recovery of venom from nematocysts of cubozoans is investigated to decrease the variation displayed between authors due to differing extraction techniques. The use of a mini bead mill beater, as investigated in this trial, allows for the rapid extraction of venom from nematocysts and is devoid of the previously isolated problems experienced with other methods of venom isolation, such as excessive heat build up. PMID:15246760

Carrette, T; Seymour, J

2004-08-01

367

Stokesian jellyfish: Viscous locomotion of bilayer vesicles  

E-print Network

Motivated by recent advances in vesicle engineering, we consider theoretically the locomotion of shape-changing bilayer vesicles at low Reynolds number. By modulating their volume and membrane composition, the vesicles can be made to change shape quasi-statically in thermal equilibrium. When the control parameters are tuned appropriately to yield periodic shape changes which are not time-reversible, the result is a net swimming motion over one cycle of shape deformation. For two classical vesicle models (spontaneous curvature and bilayer coupling), we determine numerically the sequence of vesicle shapes through an enthalpy minimization, as well as the fluid-body interactions by solving a boundary integral formulation of the Stokes equations. For both models, net locomotion can be obtained either by continuously modulating fore-aft asymmetric vesicle shapes, or by crossing a continuous shape-transition region and alternating between fore-aft asymmetric and fore-aft symmetric shapes. The obtained hydrodynamic e...

Evans, Arthur A; Lauga, Eric

2010-01-01

368

The Jelly-Fish of Lake Urumiah  

Microsoft Academic Search

IN Mr. Curzon's recently-published work ``Persia and the Persian Question'' (vol. i. p. 533), he writes as follows:-``When the wind blows on Lake Urumiah, sheets of saline foam are seen scudding along the surface, and the salt is left upon the shore in a solid efflorescence, sometimes several inches thick. No fish or molluscs live in the waters, whose sole

P. L. Sclater

1893-01-01

369

Propulsion in Cubomedusae: Mechanisms and Utility  

PubMed Central

Evolutionary constraints which limit the forces produced during bell contractions of medusae affect the overall medusan morphospace such that jet propulsion is limited to only small medusae. Cubomedusae, which often possess large prolate bells and are thought to swim via jet propulsion, appear to violate the theoretical constraints which determine the medusan morphospace. To examine propulsion by cubomedusae, we quantified size related changes in wake dynamics, bell shape, swimming and turning kinematics of two species of cubomedusae, Chironex fleckeri and Chiropsella bronzie. During growth, these cubomedusae transitioned from using jet propulsion at smaller sizes to a rowing-jetting hybrid mode of propulsion at larger sizes. Simple modifications in the flexibility and kinematics of their velarium appeared to be sufficient to alter their propulsive mode. Turning occurs during both bell contraction and expansion and is achieved by generating asymmetric vortex structures during both stages of the swimming cycle. Swimming characteristics were considered in conjunction with the unique foraging strategy used by cubomedusae. PMID:23437122

Colin, Sean P.; Costello, John H.; Katija, Kakani; Seymour, Jamie; Kiefer, Kristen

2013-01-01

370

Propulsion in cubomedusae: mechanisms and utility.  

PubMed

Evolutionary constraints which limit the forces produced during bell contractions of medusae affect the overall medusan morphospace such that jet propulsion is limited to only small medusae. Cubomedusae, which often possess large prolate bells and are thought to swim via jet propulsion, appear to violate the theoretical constraints which determine the medusan morphospace. To examine propulsion by cubomedusae, we quantified size related changes in wake dynamics, bell shape, swimming and turning kinematics of two species of cubomedusae, Chironex fleckeri and Chiropsella bronzie. During growth, these cubomedusae transitioned from using jet propulsion at smaller sizes to a rowing-jetting hybrid mode of propulsion at larger sizes. Simple modifications in the flexibility and kinematics of their velarium appeared to be sufficient to alter their propulsive mode. Turning occurs during both bell contraction and expansion and is achieved by generating asymmetric vortex structures during both stages of the swimming cycle. Swimming characteristics were considered in conjunction with the unique foraging strategy used by cubomedusae. PMID:23437122

Colin, Sean P; Costello, John H; Katija, Kakani; Seymour, Jamie; Kiefer, Kristen

2013-01-01

371

Field experiments in the control of a Jellyfish tracking ROV  

Microsoft Academic Search

Continuing ocean experiments demonstrate specific applications in which a jelly-tracking ROV pilot assist enhances collection of scientific data. Recent results have repeatedly demonstrated the tracker's ability to follow a jelly target for extended periods, as long as 34 minutes. Thus far, experimental demonstrations of the jelly tracker have incorporated a linear control law. This paper presents extensions to the control

Jason Rife; Stephen M. Rock

2002-01-01

372

Spatial aggregations of the swarming jellyfish Pelagia noctiluca (Scyphozoa)  

Microsoft Academic Search

In the Adriatic Sea, the spatial distribution and aggregation aspects of swarning Pelagia noctiluca (Forskål, 1775) were studied by SCUBA divers from August 1984 to November 1985. Medusae were asually distributed in the upper 20- to 30-m layer. Dense aggregations caused by wind, currents and tidal phenomena occurred only in shallow coastal waters. Maximum population densities of swarms drifting freely

D. Zavodnik

1987-01-01

373

Central control of swimming in the cubomedusan jellyfish Carybdea rastonii  

Microsoft Academic Search

1.Swimming in the cubomedusaCarybdea rastonii is controlled by a subumbrellar nerve net. Neurons that make up this net, including “giant” neurons, make random synaptic contacts with each other and with the circular subumbrellar swimming muscles (Figs. 1–3).2.Extracellularly recorded swimming impulses originate in the rhopalia and spread throughout the subumbrellar nerve net, initiating contractions of the subumbrellar musculature (Fig. 4).3.Intracellular recordings

Richard A. Satterlie

1979-01-01

374

Graviceptor development in jellyfish ephyrae in space and on Earth  

NASA Technical Reports Server (NTRS)

Graviceptor (rhopalium) development in Aurelia aurita ephyrae which developed on Earth and in space during the nine-day NASA SLS-1 mission was compared. The space-developed ephyrae made graviceptors which were morphologically similar to those of their ground-based controls. Rhopalia of both groups developed statocysts with statoliths, ocelli, ciliated mechanoreceptor cells, and immature touch-plates with one type of hair cell. The number of rhopalia formed per arm of ephyrae of both groups revealed no significant differences. The number of statoliths formed per rhopalium was statistically higher in ephyrae which were induced to form in space with iodine than in L(Launch)+8h controls. Statolith numbers were not significantly different between Earth-formed control ephyrae and those formed from polyps induced on Earth and then sent into space 24h and 48h later. Statolith loss from rhopalia was significantly enhanced in the space-maintained ephyrae in artificial sea water (ASW) as compared to their controls. Ephyrae formed through thyroxine treatment and those maintained in thyroxine in space had statolith numbers comparable to thyroxine-treated controls. Pulsing abnormalitities seen in some space-developed ephyrae suggest that some space-formed ephyrae may have developed abnormal rhopalia because normal rhopalia development and function is necessary for normal pulsing.

Spangenberg, D. B.; Jernigan, T.; Philput, C.; Lowe, B.

1994-01-01

375

Graviceptor development in jellyfish ephyrae in space and on earth  

NASA Astrophysics Data System (ADS)

Graviceptor (rhopalium) development in Aurelia aurita ephyrae which developed on Earth and in space during the nine-day NASA SLS-1 mission was compared. The space-developed ephyrae made graviceptors which were morphologically similar to those of their ground-based controls. Rhopalia of both groups developed statocysts with statoliths, ocelli, ciliated mechanoreceptor cells, and immature touch-plates with one type of hair cell. The number of rhopalia formed per arm of ephyrae of both groups revealed no significant differences. The number of statoliths formed per rhopalium was statistically higher in ephyrae which were induced to form in space with iodine than in L(Launch)+8h controls. Statolith numbers were not significantly different between Earth-formed control ephyrae and those formed from polyps induced on Earth and then sent into space 24h and 48h later. Statolith loss from rhopalia was significantly enhanced in the space-maintained ephyrae in ASW as compared to their controls. Ephyrae formed through thyroxine treatment and those maintained in thyroxine in space had statolith numbers comparable to thyroxine-treated controls. Pulsing abnormalities seen in some space-developed ephyrae suggest that some space-formed ephyrae may have developed abnormal rhopalia because normal rhopalia development and function is necessary for normal pulsing.

Spangenberg, D. B.; Jernigan, T.; Philput, C.; Lowe, B.

1994-08-01

376

Neuronal control of swimming in jellyfish: a comparative story  

Microsoft Academic Search

The swim-control systems of hydrozoan and scyphozoan medusae show distinct differences despite similarity in the mechanics of swimming in the two groups. This dichotomy was first demonstrated by G.J. Romanes at the end of the 19th century, yet his results still accurately highlight differences in the neuronal control systems in the two groups. A review of current information on swim-control

Richard A. Satterlie

2002-01-01

377

Trophic relationships of the freshwater jellyfish Craspedacusta sowerbyi Lankester 1880  

Microsoft Academic Search

The medusae of the hydrozoan Craspedacusta sowerbyi appear in September in a variety of ponds and lakes in Wisconsin. Short term laboratory feeding trials in about 1 liter of water indicate that the medusae (11.6-mm diam) consume zooplankton ranging in size from about 0.2 to 2.0 mm and kill but do not eat nekton up to 8.8 mm long. Clearance

STANLEY I. DODSON; SCOTT D. COOPER

1983-01-01

378

Jellyfish: A Conceptual Model for the AS Internet Topology  

Microsoft Academic Search

Several novel concepts and tools have revolution- ized our understanding of the Internet topology. Most of the existing efforts attempt to develop accurate analytical models. In this paper, our goal is to develop an effective conceptual model: a model that can be easily drawn by hand, while at the same time, it captures significant macro- scopic properties. We build the

Georgos Siganos; U. C. Riverside; Sudhir L Tauro; Michalis Faloutsos

379

Adults feed both during the day and at night, often div-ing hundreds of metres to the deep scattering layer  

E-print Network

. Subjects were presented with visual cues (a plastic jellyfish; white plastic shapes [circle, square jellyfish, Cyanea capillata; moon jellyfish, Au- relia aurita; and a ctenophore, Ocyropsis sp., introduced

Milton, Sarah

380

A Randomized, Controlled Field Trial for the Prevention of Jellyfish Stings With a Topical Sting Inhibitor  

Microsoft Academic Search

Background. Jellyfi sh stings are a common occurrence among ocean goers worldwide with an estimated 150 million envenomations annually. Fatalities and hospitalizations occur annually, particularly in the Indo-Pacifi c regions. A new topical jellyfi sh sting inhibitor based on the mucous coating of the clown fi sh prevents 85% of jellyfi sh stings in labora- tory settings. The fi eld

David R. Boulware

2006-01-01

381

Macro-morphological variation among cryptic species of the moon jellyfish, Aurelia (Cnidaria: Scyphozoa)  

Microsoft Academic Search

Morphological variation in qualitative and quantitative features is compared among species of Aurelia defined a priori using molecular criteria. Macro-morphological features were more numerous than previously implied (28 cf. 17), most were variable (26 of 28), and all species were morphologically distinguishable using univariate, multivariate and phylogenetic statistics. However, due to discrepant morphological descriptions, Aurelia spp. 3, 4, and 6

M. N. Dawson

2003-01-01

382

The conserved mitochondrial gene distribution in relatives of Turritopsis nutricula, an immortal jellyfish  

PubMed Central

Turritopsis nutricula (T. nutricula) is the one of the known reported organisms that can revert its life cycle to the polyp stage even after becoming sexually mature, defining itself as the only immortal organism in the animal kingdom. Therefore, the animal is having prime importance in basic biological, aging, and biomedical researches. However, till date, the genome of this organism has not been sequenced and even there is no molecular phylogenetic study to reveal its close relatives. Here, using phylogenetic analysis based on available 16s rRNA gene and protein sequences of Cytochrome oxidase subunit-I (COI or COX1) of T. nutricula, we have predicted the closest relatives of the organism. While we found Nemopsis bachei could be closest organism based on COX1 gene sequence; T. dohrnii may be designated as the closest taxon to T. nutricula based on rRNA. Moreover, we have figured out four species that showed similar root distance based on COX1 protein sequence. PMID:25352727

Devarapalli, Pratap; Kumavath, Ranjith N; Barh, Debmalya; Azevedo, Vasco

2014-01-01

383

The conserved mitochondrial gene distribution in relatives of Turritopsis nutricula, an immortal jellyfish.  

PubMed

Turritopsis nutricula (T. nutricula) is the one of the known reported organisms that can revert its life cycle to the polyp stage even after becoming sexually mature, defining itself as the only immortal organism in the animal kingdom. Therefore, the animal is having prime importance in basic biological, aging, and biomedical researches. However, till date, the genome of this organism has not been sequenced and even there is no molecular phylogenetic study to reveal its close relatives. Here, using phylogenetic analysis based on available 16s rRNA gene and protein sequences of Cytochrome oxidase subunit-I (COI or COX1) of T. nutricula, we have predicted the closest relatives of the organism. While we found Nemopsis bachei could be closest organism based on COX1 gene sequence; T. dohrnii may be designated as the closest taxon to T. nutricula based on rRNA. Moreover, we have figured out four species that showed similar root distance based on COX1 protein sequence. PMID:25352727

Devarapalli, Pratap; Kumavath, Ranjith N; Barh, Debmalya; Azevedo, Vasco

2014-01-01

384

Evolution of box jellyfish (Cnidaria: Cubozoa), a group of highly toxic invertebrates  

PubMed Central

Cubozoa (Cnidaria: Medusozoa) represents a small clade of approximately 50 described species, some of which cause serious human envenomations. Our understanding of the evolutionary history of Cubozoa has been limited by the lack of a sound phylogenetic hypothesis for the group. Here, we present a comprehensive cubozoan phylogeny based on ribosomal genes coding for near-complete nuclear 18S (small subunit) and 28S (large subunit) and partial mitochondrial 16S. We discuss the implications of this phylogeny for our understanding of cubozoan venom evolution, biogeography and life-history evolution. Our phylogenetic hypothesis suggests that: (i) the last common ancestor of Carybdeida probably possessed the mechanism(s) underlying Irukandji syndrome, (ii) deep divergences between Atlantic and Indo-Pacific clades may be explained by ancient vicariant events, and (iii) sexual dimorphism evolved a single time in concert with complex sexual behaviour. Furthermore, several cubozoan taxa are either para- or polyphyletic, and we address some of these taxonomic issues by designating a new family, Carukiidae, a new genus, Copula, and by redefining the families Tamoyidae and Tripedaliidae. Lastly, cubozoan species identities have long been misunderstood and the data presented here support many of the recent scientific descriptions of cubozoan species. However, the results of a phylogeographic analysis of Alatina moseri from Hawai'i and Alatina mordens from Australia indicate that these two nominal species represent a single species that has maintained metapopulation cohesion by natural or anthropogenic dispersal. PMID:19923131

Bentlage, Bastian; Cartwright, Paulyn; Yanagihara, Angel A.; Lewis, Cheryl; Richards, Gemma S.; Collins, Allen G.

2010-01-01

385

Jellyfish and other cnidarian envenomations cause pain by affecting TRPV1 channels  

PubMed Central

Cnidarian envenomations cause a burning-pain sensation of which the underlying mechanisms are unknown. Activation of TRPV1, a non-selective cation channel expressed in nociceptive neurons, leads to cell depolarisation and pain. Here, we show in vitro and in vivo evidence for desensitization-dependent TRPV1 activation in cnidarian envenomations. Cnidarian venom induced a nociceptive reactivity, comparable to capsaicin, in laboratory rats, which could be reduced by the selective TRPV1 antagonist, BCTC. These findings are the first to explain at least part of the symptomology of cnidarian envenomations and provide insights into the design of more effective treatments for this global public health problem. PMID:17010344

Cuypers, Eva; Yanagihara, Angel; Karlsson, Evert; Tytgat, Jan

2007-01-01

386

The Mesoderm Specification Factor Twist in the Life Cycle of Jellyfish  

Microsoft Academic Search

The basic helix-loop-helix (bHLH) transcription factor Twist is highly conserved from Drosophila to vertebrates and plays a major role in mesoderm specification of triploblasts. The presence of a Twist homologue in diploblasts such as the cnidarian Podocoryne carnea raises questions on the evolution of mesoderm, the third cell layer characteristic for triploblasts. Podocoryne Twist is expressed in the early embryo

Jürg Spring; Nathalie Yanze; Arnoud M. Middel; Michael Stierwald; Hans Gröger; Volker Schmid

2000-01-01

387

First record of encysted metacercariae in hydrozoan jellyfishes and ctenophores of the southern Atlantic.  

PubMed

Three species of pelagic coelenterates and ctenophores captured in Mar del Plata port, Buenos Aires, Argentina, were examined for digenean parasites. Encysted metacercariae were observed and collected. Cysts were found in the mesoglea of the hydromedusae Phialidium sp. and Liriope tetraphylla, and in the ectenophore Mnemiopsis macradyi. The morphology of the worms resembles that of the lepocreadiid digeneans. This is the first record for a metacercaria encysted in hydromedusae or ctenophores. PMID:8604116

Martorelli, S R

1996-04-01

388

Jellyfish: Evidence of Extreme Ram-pressure Stripping in Massive Galaxy Clusters  

NASA Astrophysics Data System (ADS)

Ram-pressure stripping by the gaseous intracluster medium has been proposed as the dominant physical mechanism driving the rapid evolution of galaxies in dense environments. Detailed studies of this process have, however, largely been limited to relatively modest examples affecting only the outermost gas layers of galaxies in nearby and/or low-mass galaxy clusters. We here present results from our search for extreme cases of gas-galaxy interactions in much more massive, X-ray selected clusters at z > 0.3. Using Hubble Space Telescope snapshots in the F606W and F814W passbands, we have discovered dramatic evidence of ram-pressure stripping in which copious amounts of gas are first shock compressed and then removed from galaxies falling into the cluster. Vigorous starbursts triggered by this process across the galaxy-gas interface and in the debris trail cause these galaxies to temporarily become some of the brightest cluster members in the F606W passband, capable of outshining even the Brightest Cluster Galaxy. Based on the spatial distribution and orientation of systems viewed nearly edge-on in our survey, we speculate that infall at large impact parameter gives rise to particularly long-lasting stripping events. Our sample of six spectacular examples identified in clusters from the Massive Cluster Survey, all featuring M F606W < -21 mag, doubles the number of such systems presently known at z > 0.2 and facilitates detailed quantitative studies of the most violent galaxy evolution in clusters. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with programs GO-10491, -10875, -12166, and -12884.

Ebeling, H.; Stephenson, L. N.; Edge, A. C.

2014-02-01

389

Jellyfish: Evidence of extreme ram-pressure stripping in massive galaxy clusters  

E-print Network

Ram-pressure stripping by the gaseous intra-cluster medium has been proposed as the dominant physical mechanism driving the rapid evolution of galaxies in dense environments. Detailed studies of this process have, however, largely been limited to relatively modest examples affecting only the outermost gas layers of galaxies in nearby and/or low-mass galaxy clusters. We here present results from our search for extreme cases of gas-galaxy interactions in much more massive, X-ray selected clusters at $z>0.3$. Using Hubble Space Telescope (HST) snapshots in the F606W and F814W passbands, we have discovered dramatic evidence of ram-pressure stripping in which copious amounts of gas are first shock compressed and then removed from galaxies falling into the cluster. Vigorous starbursts triggered by this process across the galaxy-gas interface and in the debris trail cause these galaxies to temporarily become some of the brightest cluster members in the F606W passband, capable of outshining even the Brightest Cluster...

Ebeling, Harald; Edge, Alastair C

2013-01-01

390

Further observations on the biology of the sea nettle and jellyfishes in Chesapeake Bay  

Microsoft Academic Search

The sessile or polyp stage ofChrysaora quinquecirrha, the sea nettle, is likely to be found in Chesapeake Bay and its tributaries on the hard substrates wherever salinities from\\u000a 7 to 20% occur. From experimental studies in field and laboratory, we found that the planulae, larval stage of the sea nettle,\\u000a set on oyster shells which were placed off the CBL

David G. Cargo; Leonard P. Schultz

1967-01-01

391

Jellyfish and Ctenophore Blooms Coincide with Human Proliferations and Environmental Perturbations  

NASA Astrophysics Data System (ADS)

Human populations have been concentrated along and exploiting the coastal zones for millennia. Of regions with the highest human impacts on the oceans ( Halpern et al. 2008 ), 6 of the top 10 have recently experienced blooms or problems with jellies. I review the time lines of human population growth and their effects on the coastal environment. I explore evidence suggesting that human activities - specifically, seafood harvest, eutrophication, hard substrate additions, transport of nonindigenous species, aquaculture, and climate change - may benefit jelly populations. Direct evidence is lacking for most of these factors; however, numerous correlations show abundant jellies in areas with warm temperatures and low forage fish populations. Jelly populations fluctuate in ˜10- and ˜20-year cycles in concert with solar and climate cycles. Global warming will provide a rising baseline against which climate cycles will cause fluctuations in jelly populations. The probable acceleration of anthropogenic effects may lead to further problems with jellies.

Purcell, Jennifer E.

2012-01-01

392

Distribution, abundance, and predation effects of epipelagic ctenophores and jellyfish in the western Arctic Ocean  

NASA Astrophysics Data System (ADS)

The Arctic Ocean is undergoing changes at an unprecedented rate because of global climate change. Especially poorly-studied in arctic waters are the gelatinous zooplankton, which are difficult to study using traditional oceanographic methods. A distinct zooplanktivore community was characterized in the surface 100 m by use of a Remotely Operated Vehicle, net collections, and SCUBA diving. The large scyphomedusa, Chrysaora melanaster, was associated with the warm Pacific water at ˜35-75 m depth. A diverse ctenophore community lived mainly above the C. melanaster layer, including Dryodora glandula, a specialized predator of larvaceans, Beroe cucumis, a predator of other ctenophores, and the extremely fragile Bolinopsis infundibulum, which was the most abundant species. Gut content analyses showed that Mertensia ovum selectively consumed the largest copepods ( Calanus spp.) and amphipods ( Parathemisto libellula); B. infundibulum consumed smaller copepods and pteropods ( Limacina helicina). Large copepods were digested by M. ovum in ˜12 h at -1.5 to 0 °C, but by B. infundibulum in only ˜4 h. We estimated that M. ovum consumed an average of ˜2% d -1 of the Calanus spp. copepods and that B. infundibulum consumed ˜4% d -1 of copepods <3 mm prosome length. These are significant consumption rates given that Calanus spp. have life-cycles of 2 or more years and are eaten by vertebrates including bowhead whales and arctic cod.

Purcell, Jennifer E.; Hopcroft, Russell R.; Kosobokova, Ksenia N.; Whitledge, Terry E.

2010-01-01

393

Jellyfish and ctenophore blooms coincide with human proliferations and environmental perturbations.  

PubMed

Human populations have been concentrated along and exploiting the coastal zones for millennia. Ofregions with the highest human impacts on the oceans (Halpern et al. 2008), 6 of the top 10 have recently experienced blooms or problems with jellies. I review the time lines of human population growth and their effects on the coastal environment. I explore evidence suggesting that human activities--specifically, seafood harvest, eutrophication, hard substrate additions, transport ofnonindigenous species, aquaculture, and climate change--may benefit jelly populations. Direct evidence is lacking for most of these factors; however, numerous correlations show abundant jellies in areas with warm temperatures and low forage fish populations. Jelly populations fluctuate in approximately 10- and approximately 20-year cycles in concert with solar and climate cycles. Global warming will provide a rising baseline against which climate cycles will cause fluctuations in jelly populations. The probable acceleration of anthropogenic effects may lead to further problems with jellies. PMID:22457974

Purcell, Jennifer E

2012-01-01

394

Optical properties of the iridescent organ of the comb-jellyfish Beroë cucumis (Ctenophora)  

NASA Astrophysics Data System (ADS)

Using transmission electron microscopy, analytical modeling, and detailed numerical simulations, the iridescence observed from the comb rows of the ctenophore Beroë cucumis was investigated. It is shown that the changing coloration which accompanies the beating of comb rows as the animal swims can be explained by the weakly-contrasted structure of the refractive index induced by the very coherent packing of locomotory cilia. The colors arising from the narrow band-gap reflection are shown to be highly saturated and, as a function of the incidence angle, cover a wide range of the visible and ultraviolet spectrum. The high transparency of the structure at the maximal bioluminescence wavelength is also explained.

Welch, Victoria; Vigneron, Jean Pol; Lousse, Virginie; Parker, Andrew

2006-04-01

395

Optical properties of the iridescent organ of the comb-jellyfish Beroë cucumis (Ctenophora)  

Microsoft Academic Search

Using transmission electron microscopy, analytical modeling, and detailed numerical simulations, the iridescence observed from the comb rows of the ctenophore Beroë cucumis was investigated. It is shown that the changing coloration which accompanies the beating of comb rows as the animal swims can be explained by the weakly-contrasted structure of the refractive index induced by the very coherent packing of

Victoria Welch; Jean Pol Vigneron; Virginie Lousse; Andrew Parker

2006-01-01

396

Jellyfish Lake, Palau: early diagenesis of organic matter in sediments of an anoxic marine lake  

USGS Publications Warehouse

The major postdepositional change in the sedimentary organic matter is carbohydrate biodegradation. Lignin and aliphatic substances are preserved in the sediments. Dissolved organic matter in pore waters is primarily composed of carbohydrates, reflecting the degradation of sedimentary carbohydrates. Rate constants for organic carbon degradation and sulfate reduction in sediments of the lake are about 10?? lower than in other anoxic sediments. This may reflect the vascular plant source and partly degraded nature of the organic matter reaching the sediments of the lake. -from Authors

Orem, W.H.; Burnett, W.C.; Landing, W.M.; Lyons, W.B.; Showers, W.

1991-01-01

397

Rock preference of planulae of jellyfish Aurelia aurita (Linnaeus 1758) for settlement in the laboratory  

NASA Astrophysics Data System (ADS)

Planulae of Aurelia aurita were exposed to 11 types of rocks (basalt, gabbro, granite, rhyolite, sandstone, limestone, conglomerate, gneiss, quartzite, marble and schist) to examine their attachment preference among rock material and position. Numbers of attached polyps was the highest on marble and the least on limestone. Their preference with regard to settling position was the same among the rocks, showing the highest density of polyps on the underside (88.5%) compared to upper (23.6%) and perpendicular sides (10.3%) of rock. The results showed that while position preference is more important than rock property, higher numbers of polyps were observed in rocks with a medium surface hardness.

Yoon, Won Duk; Choi, Sung-Hwan; Han, Changhoon; Park, Won Gyu

2014-06-01

398

marine environment SUMMER 2005 Issue 2  

E-print Network

HARBOUR SEAL TEMPERATURE EFFECTS ON MOON JELLYFISH ICONOGRAPHY AND JELLYFISH EVOLUTION ANGLERFISH FEEDING IN THE SHETLANDS JELLYFISH INVADE POWER STATIONS CTENOPHORES IN THE BLACK SEA HUMAN JELLYFISH INTERACTIONS UNIQUE THE PURPLE CLAM Reproduction in sharks and rays The complex world of siphonophores JELLYFISH MAY BENEFIT FROM

Dunn, Casey

399

Bell Pettigrew Museum of Natural History  

E-print Network

such as jellyfish. On this basis, two subphyla are classified: the Medusozoa, in which a medusa occurs in the life. Some scyphozoan jellyfish (e.g. the lion's mane jellyfish, Cyanea capillata ) can reach over 2 metres.g. jellyfish ). The sea wasp is one of the world's most dangerous jellyfish. It kills several people each year

Brierley, Andrew

400

Young, L., & Saxe, R. (2008). The neural basis of belief encoding and integration in moral judgment. Neuroimage, 40(4), 1912-1920.  

E-print Network

: JELLYFISH Janet and her neighbor are kayaking in a part of the ocean with lots of jellyfish. Janet the jellyfish don't sting and are totally harmless. B. It is not safe to swim in the ocean because the jellyfish sting, and their stings are fatal. A. Since Janet read information that said the ocean's jellyfish

Saxe, Rebecca

2008-01-01

401

ICES J. mar. Sci., 52: 575581. 1995 Medusae, siphonophores, and ctenophores as planktivorous  

E-print Network

serious declines, it is relevant to recognize that the carnivorous "jellyfishes" are ubiquitous, feeding, fisheries, hydromedusae jellyfish Mnemiopsis, Nanomia, scyphomedusae, siphonophores, submersibles either by fishes or jellyfishes, will be discussed here. I hope to convince the reader that in fact

Carrington, Emily

402

Protein-protein complexation in bioluminescence  

E-print Network

systems of marine organisms, including bacteria, jellyfish and soft corals, with particular focus) from the jellyfish Clytia gregaria, solved by means of X- ray crystallography, NMR mapping, 1952; Lee, 2008). Bioluminescent organisms such as bacteria, fireflies, jellyfish, worms, fungi

Zhijie, Liu

403

Biomechanics Phenotypic plasticity in  

E-print Network

Biomechanics Phenotypic plasticity in juvenile jellyfish medusae facilitates effective animal and altered functionality. Previous studies have indicated that Scyphozoan jellyfish ontogeny accommo- dates; ontogeny; jellyfish 1. INTRODUCTION The swimming and feeding performance of marine ani- mals depends

Dabiri, John O.

404

BUREAU' OF COMMERCIAL FISHE_..__ UNITED STATES DEPARTMENT OF THE INTERIOR  

E-print Network

---------------------------------------------- 77 Jellyfish----------------------------------------------- 79 Environment: Marine, the Anadromous Fish Act of 1965, and the Jellyfish Act of 1966. Information presented is intended to provide

405

Into the Curriculum. Dramatics/Reading/Language Arts: Jellyfish Jiggle and More; Reading/Language Arts: Birthstone Folklore; Science: Jellyfish FAQ; Science: Minerals in Caves; Social Studies: Mapping the Oceans.  

ERIC Educational Resources Information Center

Provides five fully developed library media activities that are designed for use with specific curriculum units in dramatics, reading, language arts, science, and social studies. Library media skills, curriculum objectives, grade levels, resources, instructional roles, activities and procedures, evaluation, and follow-up are describes for each…

School Library Media Activities Monthly, 2003

2003-01-01

406

Reproduction and life history strategies of the common jellyfish, Aurelia aurita, in relation to its ambient environment  

Microsoft Academic Search

The scyphozoan Aurelia aurita (Linnaeus) is a cosmopolitan species, having been reported from a variety of coastal and shelf sea environments around the world. It has been extensively studied over the last 100 years or so, and examination of the literature reveals three striking features: (1) the presence of populations in a wide range of environmental conditions; (2) large inter-population

Cathy H. Lucas

2001-01-01

407

Characterization and expression analysis of an ancestor-type Pax gene in the hydrozoan jellyfish Podocoryne carnea  

Microsoft Academic Search

We characterized a Pax gene from the hydrozoan Podocorynecarnea. It is most similar to cnidarian Pax-B genes and encodes a paired domain, a homeodomain and an octapeptide. Expression analysis demonstrates the presence of Pax-B transcripts in eggs, the ectoderm of the planula larva and in a few scattered cells in the apical polyp ectoderm. In developing and mature medusae, Pax-B

Hans Gröger; Patrick Callaerts; Walter J. Gehring; Volker Schmid

2000-01-01

408

Evolution of Paired Domains: Isolation and Sequencing of Jellyfish and Hydra Pax Genes Related to Pax5 and Pax6  

Microsoft Academic Search

Pax proteins are a family of transcription factors with a highly conserved paired domain; many members also contain a paired-type homeodomain and\\/or an octapeptide. Nine mammalian Pax genes are known and classified into four subgroups: Pax-1\\/9, Pax-2\\/5\\/8, Pax-3\\/7, and Pax-4\\/6. Most of these genes are involved in nervous system development. In particular, Pax-6 is a key regulator that controls eye

Hongmin Sun; Andrei Rodin; Yihong Zhou; Douglas P. Dickinson; Donald E. Harper; David Hewett-Emmett; Wen-Hsiung Li

1997-01-01

409

Jellyfish Support High Energy Intake of Leatherback Sea Turtles (Dermochelys coriacea): Video Evidence from Animal-Borne Cameras  

Microsoft Academic Search

The endangered leatherback turtle is a large, highly migratory marine predator that inexplicably relies upon a diet of low-energy gelatinous zooplankton. The location of these prey may be predictable at large oceanographic scales, given that leatherback turtles perform long distance migrations (1000s of km) from nesting beaches to high latitude foraging grounds. However, little is known about the profitability of

Susan G. Heaslip; Sara J. Iverson; W. Don Bowen; Michael C. James

2012-01-01

410

Swimming depths of the giant jellyfish Nemopilema nomurai investigated using pop-up archival transmitting tags and ultrasonic pingers  

Microsoft Academic Search

The swimming depths of 12 individual Nemopilema nomurai with bell diameters of 0.8–1.6 m were investigated using pop-up archival transmitting tags and ultrasonic pingers, and the\\u000a validity of the research method was evaluated. The N. nomurai studied frequently showed vertical movement, with the swimming depth ranging from 0 to 176 m, The mean swimming depths of\\u000a most individuals were less than 40 m.

Naoto Honda; Toshihiro Watanabe; Yoshiki Matsushita

2009-01-01

411

Reproduction of the giant jellyfish, Nemopilema nomurai (Scyphozoa: Rhizostomeae), in 2006-2008 as peripherally-transported populations  

Microsoft Academic Search

This study investigated the sexual maturation process, release of spermatozoa or eggs and oocyte diameter of the rhizostomid medusae Nemopilema nomurai using samples collected from August 2006 to June 2008 from the waters around Korea and Japan, including peripheral areas outside the species' usual habitat. Immature medusae were observed from June to October only in the western sector of the

Naoki Iguchi; Hye Eun Lee; Won Duk Yoon; Suam Kim

2010-01-01

412

Questioning the Rise of Gelatinous Zooplankton in the World's Oceans Author(s): Robert H. Condon, William M. Graham, Carlos M. Duarte, Kylie A. Pitt, Cathy H.  

E-print Network

by "nuisance" jellyfish. We question this current paradigm by presenting a broad overview of gelatinous zooplankton blooms. Keywords: bloom, media, jellyfish, salp, global synthesis by "nuisance" jellyfish. We of contempo- rary gelatinous zooplankton blooms? What is the human perception of changes in jellyfish

Adolphs, Ralph

413

Impact of Denial of Service Attacks on Ad Hoc Imad Aad Jean-Pierre Hubaux Edward W. Knightly  

E-print Network

the damage that difficult-to-detect attackers can cause. The first attack we study, called the JellyFish devastating effects. The second is the Black Hole attack, which has effects similar to the JellyFish to as JellyFish (JF). Previously studied attackers disobey protocol rules; on the contrary, JellyFish conform

Knightly, Edward W.

414

Hydrobiologia 451: 5568, 2001. 2001 Kluwer Academic Publishers. Printed in the Netherlands.  

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Jellyfish blooms: are populations increasing globally in response to changing ocean conditions? Claudia E of jellyfish are occurring in response to some of the cumulative effects of these impacts. The issue-term increases in native jellyfish populations. A different phenomenon is demonstrated by jellyfish whose

Carrington, Emily

415

Resource Requirements of the Pacific Leatherback Turtle T. Todd Jones1,2  

E-print Network

tonnes (t) of jellyfish in its lifetime (range 924­1112) with the Pacific population consuming 2.16106 t of jellyfish annually (range 1.0­3.76106 ) equivalent to 4.26108 megajoules (MJ) (range 2.0­7.46108 ). Model and account for most of the jellyfish consumption (1.16106 t of jellyfish or 2.26108 MJ per year

Pauly, Daniel

416

Transparent Animals Snke Johnsen  

E-print Network

TRAN JELLYFISH'S MAW is the four-pointed area vis- ible in the center of this overhead image of punc relation of the jellyfish. JELLYFISH'S MAW is the four-pointed area vis- ible in the center hy- dromedusa, a close relation of the jellyfish. G

Johnsen, Sönke

417

UNIVERSIT PARIS DIDEROT -PARIS VII COLE DOCTORALE MATIRE CONDENSE ET INTERFACES  

E-print Network

morphogenesis of the jellyfish Aurelia aurita. The gastrovascular system of this jellyfish is a branched network viscoelastic gel, which structure and mechanical properties evolve during jellyfish development. These changes enhanced in the endoderm, at the tip of a growing canal, during each muscular contraction of the jellyfish

Boyer, Edmond

418

Vortex Rings in Bio-inspired and Biological Jet Propulsion Paul S. Krueger1, a  

E-print Network

. Abstract. Pulsed-jets are commonly used for aquatic propulsion, such as squid and jellyfish locomotion and jellyfish among others. Recent investigations of squid and jellyfish locomotion have demonstrated vortex ring formation during pulsed jet propulsion for several squids and jellyfishes. Parallel studies

Hynes, Wayne L.

419

Identify key design elements of desired function  

E-print Network

design Biomimetic design Optimal design 1mm a e 10m f 100m 1mm Jellyfish ephyra b c d Jellyfish muscle Medusoid muscle 1mm 1mm Supplementary Fig. 2 Jellyfish-inspired Medusoid muscle and body design. a, Muscle architecture in juvenile jellyfish showing radial and circular fiber orientations. Note: Composite image

Dabiri, John O.

420

This article was published as part of the 2009 Green Fluorescent Protein issue  

E-print Network

.1 It is now well appreciated that, aside from the jellyfish found in the Bay of Naples (Pulmo marinus) first of the jellyfish began with Osamu Shimomura's studies of the Aequorea jellyfish in the early 1960's victoria. They observed that when the circumoral ring on the underside of the jellyfish, which contains

Jiang, Wen

421

Oceana Magazine Summer 2012: Ask Dr. Pauly: Are the Oceans Jellifying?  

E-print Network

Oceana Magazine Summer 2012: Ask Dr. Pauly: Are the Oceans Jellifying? Nomura jellyfish, pictured television and newspaper reports have been filled with stories about jellyfish outbreaks in recent years. People notice jellyfish more these days ­ or is it the jellyfish that notice more people? In any case

Pauly, Daniel

422

Introduction The invention of mesoderm was crucial to the evolution of  

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(sea anemones, corals, jellyfishes and hydras) promises to be an especially informative outgroup), Scyphozoa (true jellyfishes) and Cubozoa (box jellyfishes). Most medusozoans display a biphasic life cycle where an asexual polyp phase alternates with a sexually reproducing medusa (jellyfish) phase. The medusa

Finnerty, John R.

423

Contact: Connie Barclay FOR IMMEDIATE RELEASE 301-427-8003 January 20, 2012  

E-print Network

the Pacific to feed on jellyfish. The southern portion stretches along the California coast from Point Arena on jellyfish and lay their eggs on tropical and subtropical beaches. Although very little is known about

424

MARINE ECOLOGY PROGRESS SERIES Mar Ecol Prog Ser  

E-print Network

of jellyfishes, where they find both shelter and food (Jones 1960, Noble 1963, Thiel 1970, Brodeur 1998 kinds of crustaceans are known to associate with jellyfishes, including shrimps (Bruce 1972, Marliave

Thuesen, Erik V.

425

February 26, 2004 Volume 1, Issue 6  

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the scholarships. More... URI oceanographer awarded NSF grant to study the function of jellyfish in coastal an $860,400 National Science Foundation grant to study the ecological function of small jellyfish

Rhode Island, University of

426

CHAPTER 7NOAA Research & Development CHAPTER 7 NOAA RESEARCH & DEVELOPMENT  

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jellyfish, seasonally inhabit the Chesapeake Bay from late spring to early autumn. Their sting is painful, and knowing where and when to expect these jellyfish helps people avoid them. Daily and three- day forecasts

427

MARINE ECOLOGY -PROGRESS SENES Mar. Ecol. Prog. Ser.  

E-print Network

of population density of symbiotic algae in a tropical.marine jellyfish (Mastigiassp.) L. Muscatine', F. P. ~ i, Washington 99324, USA ABSTRACT: Marine jellyfish Mastiglas sp. are abundant in marine lakes in Belau, Western

428

BioMed Central Page 1 of 11  

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Hughes* - thomas.hughes@yale.edu *Corresponding author Abstract Background: The jellyfish green The discovery that the jellyfish green fluorescent protein (GFP) can form a functional fluorophore without other

429

Defense against Routing Disruption Attacks in Mobile Ad Hoc Networks  

E-print Network

, including protocol-compliant (also known as "JellyFish") attacks. Index Terms--Denial-of-Service Attacks difficult to defend against. In [1], Aad et al. refer to such attacks as "JellyFish" (JF) attacks. While

430

Abstract--Leatherback turtles (Der-mochelys coriacea) are regularly seen  

E-print Network

Coast, where they forage on jellyfish (Scyphomedusae) during summer and fall. Aerial line- transect://www.iucnredlist.org/ (accessed 19 November 2006). #12;338 Fishery Bulletin 105(3) ally abundant jellyfish (Scyphomedusae) along

431

50 CFR 217.114 - Mitigation.  

Code of Federal Regulations, 2014 CFR

...iii) If large Sargassum rafts or large concentrations of jellyfish are observed within the safety zone, the mission launch will not continue until the Sargassum rafts or jellyfish that caused the postponement are confirmed to be outside...

2014-10-01

432

Often researchers have the stereotype of not being able to talk about their research  

E-print Network

'i division of research & graduate studies Let's Talk Science! Study jellyfish? Those stinging things of jellyfish-human interactions and much is conducted along the Neuse River Estuary in Eastern North Carolina

433

Marine animal stings or bites  

MedlinePLUS

... stings from any form of sea life, including jellyfish. Almost 2000 species of animals found in the ... stings from various types of marine life, including: jellyfish , Portuguese Man-of-War, stingray , stonefish , scorpion fish , ...

434

August 2012 Volume 9, Issue 2  

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, identifying and measuring dozens of species of jellyfish and crustaceans. The plankton images on Plankton identify interesting new behaviors in jellyfish, such as the first reported documentation of a small

435

Introduction The ability to directly measure physical interactions between  

E-print Network

of ciliated larvae (Emlet 1990) and affects the structure of LCS in the wake of a jellyfish (Katija and Dabiri of Aurelia labiata jellyfish swim- ming in the coastal waters of Long Beach, California. We analyze the DPIV

Dabiri, John O.

436

unknown title  

E-print Network

increases in jellyfish Introduction and errata ‘‘Jellyfish’ ’ section in Haddock comment Following the publication of our paper (Attrill et al. 2007), we became quickly aware of a couple of errors. We have subsequently been collaborating with Dr. Chris

unknown authors

437

Introduction The influence of fluid environments on the evolution of body  

E-print Network

is the determination of how the animal interacts with the surrounding fluid (i.e. water or air). Jellyfish required for jet Cnidarian medusae, commonly known as jellyfish, represent the earliest known animal taxa

Dabiri, John O.

438

Western Nanofabrication Facility Andrea S. Fernandes, M.Sc. thesis, supervisors: Prof. C. Tsujita and Prof. G. Southam  

E-print Network

in concretions, polished 2 mm thick sections from a jellyfish, holothurian and polychaete worm were screened testing (Zr+ irradiated condition). Figure: A) Backscattered electron micrograph of a jellyfish concretion

Lennard, William N.

439

Biophysical Methods of Neurobiology (Dieter Braun) Biophysical Methods in Neuroscience  

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protein is also present in the jellyfish A. victoria, and absorbs blue light (488 nm) emitted by aequorin Green fluorescent protein is also present in the jellyfish A. victoria, and absorbs blue light (488 nm

Kersting, Roland

440

bined alleles also targets the rearranged anti-body genes for further mutation, and that this  

E-print Network

and an outburst of an alien jellyfish Mnemiopsis leidyi. The time series data suggest overfishing as the driver of preda- tory fish has not recovered (and seems unlikely to), although the appearance of the jellyfish

Fraden, Seth

441

INTRODUCTION As a swimming or flying animal moves through its environment,  

E-print Network

jellyfish (Shadden et al., 2006; Peng and Dabiri, 2007). The identification of upstream coherent structures). For example, only fluid inside the upstream structures is sampled by a swimming jellyfish; therefore, only

Dabiri, John O.

442

gamm header will be provided by the publisher On the Approximation of Transport Pheno-  

E-print Network

-prey interaction in jellyfish to the investigation of blood flow in the cardiovascular sys- tem. Our approach Phenomena and the consideration of predator-prey interaction in jellyfish [20] to the investigation of blood

443

J. Fluid Mech. (2005), vol. 538, pp. 111136. c 2005 Cambridge University Press doi:10.1017/S002211200500515X Printed in the United Kingdom  

E-print Network

ranging from the most primitive jellyfish locomotor to the complex trans-mitral and trans-aortic blood for locomotion. Certain cnidarians (e.g. jellyfish), cephalopods (e.g. squid), and bivalves (e.g. scallops

Dabiri, John O.

444

Hydralysins, a New Category of -Pore-forming Toxins in Cnidaria*S  

E-print Network

of action. Cnidarians (corals, sea anemones, jellyfish, and hydrae) are an evolutionarily ancient group in the life threatening stings of the Portuguese Man- O-War (Physalia physalis) and of box jellyfish (4

Lebendiker, Mario

445

R E V I E W Development and Use of Fluorescent Protein  

E-print Network

such as green fluores- cent protein (GFP) from the jellyfish Ae- quorea victoria (Fig. 1, A and B) and its. victoria. Upon purification to homogeneity from the jellyfish, GFP by itself was found to fluoresce under

La Rosa, Andres H.

446

Research Statement Ellie Grano  

E-print Network

discuss an evaluation algorithm called the "jellyfish algorithm" discovered by Bigelow during his work the opportunities for undergraduate research in this area in Section 8. 4 The Jellyfish Algorithm Arising from

Bigelow, Stephen

447

Proc. Natl. Acad. Sci. USA Vol. 93, pp. 83628367, August 1996  

E-print Network

December 26, 1995) ABSTRACT The green fluorescent protein (GFP) of the jellyfish Aequorea Victoria has the photo stability of GFP. The green fluorescent protein (GFP) of the jellyfish Aequorea Victoria has

Boxer, Steven G.

448

United States Dep~rtment of the. Interior Fish and '.Ji l dlife Service  

E-print Network

_hl_·c_a~g~o~~~~~.,~I_ll_.__________________~~__________.________~July 1944 SEA Nl!;TTU1) OR JELLYFISHES Sea nettles and jellyfi.shes are strange-looking, free tropical waters. The nUlT,erous tentacles hanginr; from the um- brella- like body of a jellyfish give~anisms to vvhich the jellyfishes belong is called by scientists Coelenterates , the term l:leaning that in all

449

Mitochondrial DNA Sequence Variation in Domesticated Goldfish, Carassius Richard Beckwitt; Seiji Aoyagi  

E-print Network

. The associationbetween young whit- ing, Gadus merlangus, and the jelly-fish Cyanea cap- illata. Sarsia 3:47-55. FAHAY. Pub. 34:l-316. MANSUETTI, 1963. Symbiotic behavior betweenR. small fishes and jellyfishes, with new., AND R. T. COONEY. sociation of walleyepollock, Theragra chalcogramma, with the jellyfish, Cyanea. Copeia

Beckwitt, Richard

450

MARINE ECOLOGY PROGRESS SERIES Mar Ecol Prog Ser  

E-print Network

Published December 19 INTRODUCTION Blooms of jellyfish, often referring to pelagic cnidarians distributions (Richardson et al. 2009, Brotz et al. 2012, Purcell 2012). Jellyfish mass occurrence and apparent shifts from fish- to jellyfish-dominated systems have been linked to numerous factors such as fisheries

Aksnes, Dag L.

451

Illuminating plant biology: using fluorescent proteins for  

E-print Network

publication date 21January 2010 Abstract First discovered in jellyfish, fluorescent proteins (FPs) have been the Pacific Ocean jellyfish Aequorea victoria [2], the use of GFP and its subsequent fluo- rescent derivatives with UV or blue light, the original jellyfish-derived GFP is excited to emit green light as fluorescence

Jackson, David

452

MARINE ECOLOGY PROGRESS SERIES Mar Ecol Prog Ser  

E-print Network

· www.int-res.com *E-mail: rick.brodeur@noaa.gov Increases in jellyfish biomass in the Bering Sea a dramatic increase in jellyfish biomass over the eastern Bering Sea shelf since the early 1990s, which explore the impact of this jellyfish increase on zoo- plankton and fish communities based on field data

453

INTRODUCTION Animalfluid interactions have been hypothesized as a principal  

E-print Network

in the context of biological propulsion. Jellyfish provide a unique perspective on the evolution of propulsion (DPIV) (Willert and Gharib, 1992). We selected seven species of hydrozoan jellyfish for this comparative speed of the seven co-occurring species of free-swimming jellyfish. Using this new data, we demonstrate

Dabiri, John O.

454

50 CFR 217.84 - Mitigation.  

Code of Federal Regulations, 2012 CFR

...ii) Large concentrations of fish, jellyfish, and/or large Sargassum rafts are...delay would continue until the fish, jellyfish, and/or Sargassum rafts that cause...birds, large concentrations of fish or jellyfish, and large Sargassum mats. The...

2012-10-01

455

Introduction Pulsatile jet propulsion is one of the earliest known forms  

E-print Network

by periodically ejecting jets of water in a direction opposite to the desired trajectory. Hydromedusan jellyfish speeds (Bartol et al., 2001; Anderson and Grosenbaugh, 2005). The body plan of hydromedusan jellyfish of locomotion (Gladfelter, 1972; Daniel, 1983; Daniel, 1985). Fast-swimming hydromedusan jellyfish possess

Dabiri, John O.

456

GFP variants for multispectral imaging of living cells. Jim Haseloff  

E-print Network

the jellyfish green fluorescent protein for use as a directly visible gene marker in Arabidopsis, and developed jellyfish Aequorea victoria shares none of these problems, and there has been much interest in using, with glowing points around the margin of the jellyfish umbrella. Light arises from yellow tissue masses

Franks, Robert

457

Check List 5(1): 133138, 2009. ISSN: 1809-127X  

E-print Network

Check List 5(1): 133­138, 2009. ISSN: 1809-127X LISTS OF SPECIES 133 Neritic Jellyfishes (Cnidaria of this study was to perform a survey of the jellyfish (Cnidaria: Cubozoa and Scyphozoa) on the coast of Rio of large jellyfish, and new records of the following cubozoan and scyphozoan species were verified

Morandini, Andre C.

458

itats have not been dearly revealed . In no case is the diet of the hatchlings well known although it is assume d  

E-print Network

a diet of jellyfish (Schypho- medusidae) and tunicates, together with crustacean parasites and symbiotic fish that are associated with th e jellyfish (Brongersma 1969, Bleakney 1965) . This diet is reflected, contain crabs and jellyfish as wel l as shrimp. The guts of 10 olive ridleys captured 30 t o 50 km off

Prestwich, Ken

459

The First Mutant of the Aequorea Victoria Green Fluorescent Protein That Forms a Red Chromophore  

E-print Network

ReceiVed February 27, 2008 ABSTRACT: Green fluorescent protein (GFP) from a jellyfish, Aequorea Victoria of the jellyfish A. Victoria where GFP played a role of secondary emitter transforming blue light from). In particular, a yellow FP and a purple CP from hydroid jellyfishes were characterized. Between 1994 and 1999

Verkhusha, Vladislav V.

460

50 CFR 217.84 - Mitigation.  

Code of Federal Regulations, 2014 CFR

...ii) Large concentrations of fish, jellyfish, and/or large Sargassum rafts are...delay would continue until the fish, jellyfish, and/or Sargassum rafts that cause...birds, large concentrations of fish or jellyfish, and large Sargassum mats. The...

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