Note: This page contains sample records for the topic jellyfish chironex fleckeri from Science.gov.
While these samples are representative of the content of Science.gov,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of Science.gov
to obtain the most current and comprehensive results.
Last update: November 12, 2013.
1

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

2012-12-07

2

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

Microsoft Academic Search

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 45kDa, respectively, and both proteins are strongly antigenic to commercially available box jellyfish antivenom and rabbit polyclonal antibodies

Diane Brinkman; James Burnell

2007-01-01

3

A cell-based assay for screening of antidotes to, and antivenom against Chironex fleckeri (box jellyfish) venom  

Microsoft Academic Search

IntroductionChironex fleckeri is a large box jellyfish that has been labelled the ‘most venomous animal’ in the world. We have recently shown that the primary effect of C. fleckeri venom in vivo is cardiovascular collapse. This study utilised a cell-based assay to examine the effects of C. fleckeri venom on the proliferation of a rat aortic smooth muscle cell line.

Nicki Konstantakopoulos; Geoffrey K. Isbister; Jamie E. Seymour; Wayne C. Hodgson

2009-01-01

4

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

2007-06-26

5

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

2007-12-23

6

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

Microsoft Academic Search

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)

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

2009-01-01

7

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

Microsoft Academic Search

Intravenous verapamil prolonged survival in mice challenged with intravenous Chironex fleckeri venom prepared from clarified nematocyst suspensions. Ovoid antivenom protected mice who had been challenged but only over a limited dose range. Verapamil also enhanced the beneficial effect of ovine antivenom but again was most active only over a restricted dose range. This data suggests that there may be an,

David A Bloom; Jose Burnett

1999-01-01

8

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

Microsoft Academic Search

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 ?370 and 145kDa, and one minor cytolysin (?70kDa) were isolated. SDS-PAGE and western blot protein profiles revealed that the 370kDa haemolysin is composed of CfTX-1 and CfTX-2

Diane Brinkman; James Burnell

2008-01-01

9

Growth, Development and Temporal Variation in the Onset of Six Chironex fleckeri Medusae Seasons: A Contribution to Understanding Jellyfish Ecology  

PubMed Central

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.

Gordon, Matthew; Seymour, Jamie

2012-01-01

10

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

2012-04-23

11

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

2011-12-02

12

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

Microsoft Academic Search

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

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

2003-01-01

13

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

Microsoft Academic Search

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

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

2007-01-01

14

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

Microsoft Academic Search

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

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

2010-01-01

15

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

2009-02-20

16

A functional comparison of the venom of three Australian jellyfishChironex fleckeri, Chiropsalmus sp., and Carybdea xaymacana—on cytosolic Ca 2+, haemolysis and Artemia sp. lethality  

Microsoft Academic Search

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

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

2005-01-01

17

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

Microsoft Academic Search

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

D. A Bloom; F. F. Y Radwan; J. W Burnett

2001-01-01

18

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

Microsoft Academic Search

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

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

2007-01-01

19

Temperature effects on box jellyfish venom: a possible treatment for envenomed patients?  

Microsoft Academic Search

Objective: To determine the effect of temperature on lethality of venom from Chironex fleckeri (the potentially fatal box jellyfish). Design: Venom extracted from nematocysts of mature Chironex fleckeri specimens was exposed to temperatures between 4°C and 58°C for periods of two, five or 20 minutes, and then injected into freshwater crayfish (Cherax quadricarinatus) to assess lethality. Main outcome measure: Venom

Teresa J Carrette; Paul Cullen; Peter L Peiera; Jamie E Seymour

20

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.

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

1971-01-01

21

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

Microsoft Academic Search

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.

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

2005-01-01

22

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

Microsoft Academic Search

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?g\\/kg, i.v.) produced a transient hypertensive response (44±4mmHg; n=6) followed by hypotension and cardiovascular collapse. Concurrent artificial respiration or pretreatment with Chironex fleckeri antivenom (AV, 3000U\\/kg, i.v.) did not have any

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

2005-01-01

23

Recurrent dermatitis from jellyfish envenomation.  

PubMed Central

Jellyfish envenomation can cause an immediate local skin reaction, which is usually a painful linear vesiculourticarial eruption. Persistent, delayed, or recurrent dermatitis is less common. Because jellyfish sting reactions and their management are unfamiliar to family physicians, we describe a case of recurrent local dermatitis after jellyfish envenomation and suggest appropriate treatment. Images Figure 1

Menahem, S.; Shvartzman, P.

1994-01-01

24

Photoreceptors of cubozoan jellyfish  

Microsoft Academic Search

The anatomically sophisticated visual system of the cubozoan jellyfish Carybdea marsupialis is described. Individual cubomedusae have eight complex eyes, each with a cornea, lens, and retina of ciliated photoreceptor\\u000a cells, eight slit ocelli, and eight dimple ocelli. The photoreceptor cells of the complex eyes are bipolar and resemble vertebrate\\u000a rod cells. Each photoreceptor has an outer cylindrical light-receptive segment that

Vicki J. Martin

2004-01-01

25

Photoreceptors of cubozoan jellyfish  

Microsoft Academic Search

The anatomically sophisticated visual system of the cubozoan jellyfish Carybdea marsupialis is described. Individual cubomedusae have eight complex eyes, each with a cornea, lens, and retina of ciliated photoreceptor\\u000a cells, eight slit ocelli, and eight dimple ocelli. The photoreceptor cells of the complex eyes are bipolar and resemble vertebrate\\u000a rod cells. Each photoreceptor has an outer cylindrical light-receptive segment that

Vicki J. Martin

26

Localized neuropathy following jellyfish sting  

Microsoft Academic Search

This report describes the case of an 18 year old female who sustained a jellyfish sting on her right wrist. She subsequently developed complete radial, ulnar and median nerve palsies distal to the site of the sting, which recovered fully over the next 10 months. We believe this to be due to a direct neurotoxic effect of the jellyfish venom.

N. Peel; R. Kandler

1990-01-01

27

A case of jellyfish sting.  

PubMed

Jellyfish sting may result in a wide range of symptoms from common erythematous urticarial eruptions to the rare box-jelly induced acute respiratory failure. In Taiwan, with the increasing frequency of international travel, cases of jellyfish sting to foreigners are on the rise. We report a case of jellyfish sting with the rare presentation of painless contact dermatitis. A 38-y-o man accidentally stepped on a sea urchin with his right foot during scuba diving in a beach in Thailand. Traditional therapy with vinegar was applied on the lesion. However, when he returned to Taiwan, erythematous patches on the left thigh with linear radiations to the leg were discovered. The skin lesions had bizzare shapes and showed progressive change. No pain or numbness was noticed. Jellyfish stingwas suspected, topical medications were applied, and the patient recovered without complication. Jellyfish stings usually result in a painful erythematous eruption. In this case, though the lesion involved a large surface, there was no pain. Delayed diagnosis of jellyfish sting was due to the atypical presentation and the physician's unfamiliarity to the Thai jellyfish sting. Awareness to the wide spectrum of jellyfish sting symptoms should be promoted. PMID:11474731

Lee, N S; Wu, M L; Tsai, W J; Deng, J F

2001-08-01

28

[Jellyfish sting. A case report].  

PubMed

Jellyfish bites in Hungary are rare. Yet, from a differential diagnostic point of view this epizoonozis might gain importance given the ever-growing popularity of seaside tourism. A 10 year old female patient was stung by a jellyfish while sea-bathing in the Adriatic in the summer of 2005. A couple of minutes after the bite urticaria were formed in the contacted area accompanied by a burning and sore sensation. In a few hours the above lesions turned livid and the patient developed low-grade fever and general discomfort. In acute therapy she received thorough rinse with vinegar, antibiotic ointment and systemic calcium. General symptoms regressed within 24 hours and dermatological symptoms improved progressively. Finally, the patient grew symptomless in 4 weeks altogether due to general antihistamine and local antibiotic therapy. 3 months later the patient presented again with hyperaemic papules and an increasing itching and burning sensation in the previously jellyfish-contacted area. Histopathology showed vascular involvement and eosinophilic infiltration. The inflammatory symptoms gradually diminished to locally applied steroids in an occlusive bandage leaving behind hypopigmentation. Although bare-skin contact with the different poisonous jellyfish species usually do lead to the forming of dermatological symptoms, vascular involvement developed months after the encounter in the exposure site has seldom been published. The article covers the main potential symptoms of jellyfish stings--both local and general--going into details about the possible dermatological differential diagnoses. Furthermore, the most venomous jellyfish species, their geographical habitats, do's and don't-s of first aid, therapy and prevention are being briefly discussed by the authors. PMID:18089481

Tamás, Ildikó; Veres, Imre; Remenyik, Eva

2008-01-01

29

Clinical manifestations of jellyfish envenomation  

Microsoft Academic Search

Jellyfish produce clinical diseases in humans. Death from venom toxicity is more common than anaphylaxis. The main venom actions are on the cardiovascular, respiratory and renal systems and these agents may induce systemic symptoms accompanying their cutaneous lesions. Keloids, fat atrophy, gangrene, contractions, arthralgias, neuritis, hyperpigmentation, corneal ulcerations, vasospasm and post-envenomation herpes simplex or granuloma annulare may appear. Recurrent eruptions,

Joseph W. Burnett

1991-01-01

30

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

31

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

32

Micro- and Macrorheology of Jellyfish Extracellular Matrix  

PubMed Central

Mechanical properties of the extracellular matrix (ECM) play a key role in tissue organization and morphogenesis. Rheological properties of jellyfish ECM (mesoglea) were measured in vivo at the cellular scale by passive microrheology techniques: microbeads were injected in jellyfish ECM and their Brownian motion was recorded to determine the mechanical properties of the surrounding medium. Microrheology results were compared with macrorheological measurements performed with a shear rheometer on slices of jellyfish mesoglea. We found that the ECM behaved as a viscoelastic gel at the macroscopic scale and as a much softer and heterogeneous viscoelastic structure at the microscopic scale. The fibrous architecture of the mesoglea, as observed by differential interference contrast and scanning electron microscopy, was in accord with these scale-dependent mechanical properties. Furthermore, the evolution of the mechanical properties of the ECM during aging was investigated by measuring microrheological properties at different jellyfish sizes. We measured that the ECM in adult jellyfish was locally stiffer than in juvenile ones. We argue that this stiffening is a consequence of local aggregations of fibers occurring gradually during aging of the jellyfish mesoglea and is enhanced by repetitive muscular contractions of the jellyfish.

Gambini, Camille; Abou, Berengere; Ponton, Alain; Cornelissen, Annemiek J.M.

2012-01-01

33

Simulation of Piezoelectric Jellyfish Power Generator  

NASA Astrophysics Data System (ADS)

The energy problem is getting increasingly serious. As such, unused energy recovery technology is crucial for environmental protection, which has been investigated extensively. Several methods have been developed to utilize scavenged energy from the environment, such as waste heat, solar energy, wind energy, and tides energy to convert into useful power. There is a new idea of piezoelectric jellyfish generator which combines the utilization of sea wave and vibration energy. When sea wave passes through the jellyfish, the wave causes the tentacles to vibrate. The tentacles is made of piezoelectric polymer which can convert the strain energy into electrical energy. This paper discusses about the piezoelectric jellyfish's tentacles being disturbed by wave in the sea. We employed the commercial CFD software CFD-ACE+ 2006 to simulate this phenomenon. The parameters including its tentacle length (L) and wave propagating function (Y) are studied which affect the piezoelectric jellyfish capacity to generate power.

Wu, Yeong-Jen; Lai, Wei-Hsiang

34

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.

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

2007-01-01

35

Efficacy of a Jellyfish Sting Inhibitor in Preventing Jellyfish Stings in Normal Volunteers  

Microsoft Academic Search

Methods.—Twenty-four healthy subjects at 2 research sites were randomly assigned to receive the jellyfish sting inhibitor (Nidaria Technology Ltd, Jordan Valley, Israel) to one forearm and conven- tional sunscreen to the other arm in a blinded fashion. Subjects were stung with jellyfish tentacles on each forearm for up to 60 seconds. Erythema and pain were assessed at 15-minute intervals over

Alexa Boer Kimball; Arlen Ray Stauffer; Valeh Levy; Valerie Weaver Davis; Michael Liu; Wingfield Ellis Rehmus; Amit Lotan; Paul S. Auerbach

2004-01-01

36

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

2012-12-31

37

Jellyfish Body Plans Provide Allometric Advantages beyond Low Carbon Content.  

PubMed

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

2013-08-13

38

Elimination of Jellyfish and the Like.  

National Technical Information Service (NTIS)

The method concerns a method whereby Sea creatures of the genus Medusa (sea nettles, jellyfish) are driven to the surface of water by exposure to acoustic waves at frequencies from about 2 to about 3.2 kilohertz. The creatures may then be identified and g...

E. V. Thomas B. E. Douglas

1970-01-01

39

Jellyfish sting injury to the cornea.  

PubMed

A 25-year-old woman presented to the emergency room 2 hours after a jellyfish sting to the left eye. Centrally located linear epithelial defects were observed on slit-lamp evaluation. The epithelial defects improved but did not heal totally after meticulous patching with antibiotic ointment and cycloplegic drops. Small, subepithelial negative staining areas within the epithelial defects were observed on day 3. Confocal microscopy was performed and revealed thread-like hyperreflective structures, mainly located at the basal epithelial layer. Following debridement of the traumatized areas, the corneal epithelium healed completely in 24 hours, resulting in increased visual acuity and decreased foreign body sensation. Jellyfish stings to the eye may involve the intrusion of the nematocysts, thread-like venomous structures, into the cornea. Debridement of these foreign bodies can be helpful in the treatment of resistant cases. PMID:18831428

Sonmez, Baris; Beden, Umit; Yeter, Volkan; Erkan, Dilek

40

Jellyfish stings and their management: a review.  

PubMed

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

2013-02-22

41

Mediterranean jellyfish venoms: a review on scyphomedusae.  

PubMed

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

2010-04-04

42

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.

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

2013-01-01

43

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

44

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

2012-12-12

45

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.

Yanagihara, Angel A.; Shohet, Ralph V.

2012-01-01

46

Environmental forcing on jellyfish communities in a small temperate estuary.  

PubMed

The impact of biological, hydrodynamic and large scale climatic variables on the jellyfish community of Mondego estuary was evaluated from 2003 to 2010. Plankton samples were collected at the downstream part of the estuary. Siphonophora Muggiaea atlantica and Diphyes spp. were the main jellyfish species. Jellyfish density was generally higher in summer and since 2005 densities had increased. Summer community analysis pointed out Acartia clausi, estuarine temperature and salinity as the main driven forces for the assemblage's structure. Also, Chl a, estuarine salinity, runoff and SST were identified as the major environmental factors influencing the siphonophores summer interannual variability. Temperature influenced directly and indirectly the community and fluctuation of jellyfish blooms in the Mondego estuary. This study represents a contribution to a better knowledge of the gelatinous plankton communities in small temperate estuaries. PMID:22770533

Primo, Ana Lígia; Marques, Sónia C; Falcão, Joana; Crespo, Daniel; Pardal, Miguel A; Azeiteiro, Ulisses M

2012-06-23

47

Lagrangian coherent structures in jetting and paddling jellyfish swimming  

NASA Astrophysics Data System (ADS)

Lagrangian coherent structures (LCS) are a relatively new technique for visualizing and analysing structures and transport in complex fluid flows. In this study, we use LCS to examine the flow created by swimming jellyfish. We focus on identifying structures which contribute to feeding and propulsion and find several interesting results. Jellyfish which use different methods of propulsion create very different flow structures during swimming which are complimentary to the type of propulsion used. Additionally, we investigate the relationship between flow structures, pressure and swimming performance for the jetting Jellyfish, Sarsia tubulosa. We have previously detected structures within the bell of Sarsia tubulosa and we now focus on examining how these structures may impact the jellyfish's swimming.

Lipinski, Doug; Mohseni, Kamran

2009-11-01

48

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

2010-05-31

49

Patterns of jellyfish abundance in the North Atlantic  

Microsoft Academic Search

A number of explanations have been advanced to account for the increased frequency and intensity at which jellyfish (pelagic\\u000a cnidarians and ctenophores) blooms are being observed, most of which have been locally directed. Here, we investigate seasonal\\u000a and inter-annual patterns in abundance and distribution of jellyfish in the North Atlantic Ocean to determine if there have\\u000a been any system-wide changes

Mark J. Gibbons; Anthony J. Richardson

50

Acoustic survey of a jellyfish dominated ecosystem (Mljet Island, Croatia)  

Microsoft Academic Search

Acoustic techniques have been proposed as a new tool to assess jellyfish populations. However, the presence of mixed echoes\\u000a from jellyfish and other organisms that share their distribution often prevent accurate estimates of their abundance and distribution\\u000a being obtained. The isolated population of Aurelia inhabiting the Veliko Jezero (Big Lake-BL) of Mljet Island, in the South Adriatic Sea, offered a

G. Alvarez Colombo; A. Benovi?; A. Malej; D. Lu?i?; T. Makovec; V. Onofri; M. Acha; A. Madirolas; H. Mianzan

51

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

2011-06-23

52

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

53

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

54

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

55

Jellyfish mucin may have potential disease-modifying effects on osteoarthritis  

Microsoft Academic Search

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

Naoshi Ohta; Masato Sato; Kiminori Ushida; Mami Kokubo; Takayuki Baba; Kayoko Taniguchi; Makoto Urai; Koji Kihira; Joji Mochida

2009-01-01

56

Identification of genetically and oceanographically distinct blooms of jellyfish.  

PubMed

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

2013-01-03

57

Isolated severe median mononeuropathy caused by a jellyfish sting.  

PubMed

Neuropathies caused by jellyfish stings are extremely rare and poorly studied. A 20-year-old female patient was stung on the volar aspect of the right forearm by an unidentified species of jellyfish. Local cutaneous reaction was followed within few days by severe median mononeuropathy, involving the motor and sensory branches to the hand and forearm but sparing the palmar branch. The patient had neuropathic pain relieved by pregabaline. Electrodiagnostic studies confirmed a demyelinating lesion. Ultrasound and magnetic resonance imaging of the median nerve revealed uniform swelling with mild uptake of contrast along the forearm. Within 2 months, strength improved significantly, pain subsided, and numbness partially resolved. Literature review and discussion of the possible mechanisms and implications of this rare effect of marine animal envenomation is presented. Jellyfish sting may cause focal mononeuropathies most probably because of the local effects of the toxins. PMID:23703015

Al-Ajmi, Abdullah M; Jayappa, Sateesh; Rousseff, Rossen T

2013-06-01

58

OBSERVATIONS ON THREE S1'ECIES OF JELLYFISHES FROM  

Microsoft Academic Search

Cyanea capillata, flue pimuk jellyfish or lion's nuane, occurs in Chesapeake Bay and its tributary rivers from the latter part of November to the first of May. The largest specimens attain an umbrellar dianieter of eiglut inches, but most speci muiens observed are in flue range of four to six inclues. Pigmentatiomi varies from pink to brown in different specinuelus.

NOLAN E. RICE; V. ALLAN POWELL

59

Role of Thyroxine in Space-Developed Jellyfish.  

National Technical Information Service (NTIS)

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 ...

D. B. Spangenberg

1997-01-01

60

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

61

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

62

Influence of jellyfish blooms on carbon, nitrogen and phosphorus cycling and plankton production  

Microsoft Academic Search

Due to their boom and bust population dynamics and the enormous biomasses they can attain, jellyfish and ctenophores can have\\u000a a large influence on the cycling of carbon (C), nitrogen (N) and phosphorus (P). This review initially summarises the biochemical\\u000a composition of jellyfish, and compares and contrasts the mechanisms by which non-zooxanthellate and zooxanthellate jellyfish\\u000a acquire and recycle C, N

Kylie A. Pitt; David T. Welsh; Robert H. Condon

2009-01-01

63

First aid for jellyfish stings: do we really know what we are doing?  

PubMed

Jellyfish stings remains a common envenoming, and yet confusion appears to exist in the community as to the correct first aid. Current guidelines from the Australian Resuscitation Council still recommends ice for most jellyfish stings, although there appears to belittle evidence to support this. There is more evidence supporting the use of hot water. More research is required to simplify first aid for jellyfish stings. PMID:18251731

Little, Mark

2008-02-01

64

Project Jelly-Fish: B.R.N.O. Observations of Semiregular Variable Stars  

NASA Astrophysics Data System (ADS)

Brno Regional Network of Observers (BRNO) is a group which prefers to observe eclipsing binary stars. A team called the Jelly-Fish has been formed within BRNO for the purpose of observing variable stars other than eclipsing binaries. The observations by Jelly-Fish members are predominantly visual; CCD observing has started only recently and such observations are not yet included in our statistics. Jelly-Fish has about twenty members at this moment. This paper presents preliminary results based on Jelly-Fish observations of S Camelopardalis, AU Camelopardalis, WZ Cassiopeiae, RS Cygni, T Persei, RU Persei, and R Ursae Minoris.

Hajek, P.

2006-06-01

65

High time resolution luminosity profiles of Jellyfish (Super) Sprites  

NASA Astrophysics Data System (ADS)

We compare the time history of luminosity and VLF measurements associated with different classes of sprites. In particular we are interested in the larger "jellyfish, or super" sprites that are very bright, very brief duration sprites. Optical observations reveal these sprites are collections of multiple carrot sprites, comprised of both downward and upward propagating streamers. We find the time scales of super sprites are shorter than that for carrot sprites and column sprites. The exponential decrease in sprite luminosity has been related to the conductivity profile assumed for the middle atmosphere by [Barrington-Leigh et. al. (2002), doi: 10.1029/2001JA900117]. We investigate the possibility that the overall brighter and rapid decrease in jellyfish sprite luminosity compared to other types of sprites may be related to changes in the middle atmosphere conductivity, and/or in the driving electrostatic field associated with the causative lightning flash.

McHarg, M. G.; Ahrns, J.; Stenbaek-Nielsen, H. C.; Kammae, T.; Haaland, R. K.; Cummer, S. A.; Li, J.; Liu, N.; Yukman, P.

2011-12-01

66

Anticoagulant activity of Moon jellyfish (Aurelia aurita) tentacle extract.  

PubMed

Moon jellyfish (Aurelia aurita) tentacle extract was studied for its anticoagulant activity in vitro. The Jellyfish Tentacle Extract (JFTE) showed very strong fibrinogenolytic activity by cleaving A? and B? chain of fibrinogen molecule. The fibrinogenolytic activity was found to be stronger than some snake venom derived anticoagulants. JFTE also completely liquefied fibrin clots in 24 h. JFTE was found to contain both high and low molecular weight proteins/peptides. The fibrinogenolysis appears to be caused by high molecular weight fractions of the extract. It has been also noted that PMSF significantly reduced fibrinogenolytic activity and heating totally abolished it. Autolytic degradation of the high molecular weight protein was also noted. Autolysis slowed down, but did not abolish the fibrinogenolytic activity of the extract. PMID:22652129

Rastogi, Akriti; Biswas, Sumit; Sarkar, Angshuman; Chakrabarty, Dibakar

2012-05-28

67

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.

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

2012-01-01

68

What's on the mind of a jellyfish? A review of behavioural observations on Aurelia sp. jellyfish.  

PubMed

Aurelia sp. (scyphozoa; Moon Jellies) are one of the most common and widely distributed species of jellyfish. Their behaviours include swimming up in response to somatosensory stimulation, swimming down in response to low salinity, diving in response to turbulence, avoiding rock walls, forming aggregations, and horizontal directional swimming. These are not simple reflexes. They are species typical behaviours involving sequences of movements that are adjusted in response to the requirements of the situation and that require sensory feedback during their execution. They require the existence of specialized sensory receptors. The central nervous system of Aurelia sp. coordinates motor responses with sensory feedback, maintains a response long after the eliciting stimulus has disappeared, changes behaviour in response to sensory input from specialized receptors or from patterns of sensory input, organizes somatosensory input in a way that allows stimulus input from many parts of the body to elicit a similar response, and coordinates responding when stimuli are tending to elicit more than one response. While entirely different from that of most animals, the nervous system of Aurelia sp. includes a brain that creates numerous adaptive behaviours that are critical to the survival of these phylogenetically ancient species. PMID:20540961

Albert, David J

2010-06-09

69

Epidemiology of jellyfish stings reported to poison centers in Texas.  

PubMed

This study examined the relationship between selected factors and all human exposures involving jellyfish stings reported to Texas poison centers. Cases were obtained retrospectively from calls to poison centers in Texas and included all reported human exposures during 1998-2004 involving jellyfish stings. The distribution of cases was determined for a variety of demographic and clinical parameters. There were 423 total cases. Among the cases with a known patient age, 19.8% were <6 years of age, 53.5% were age 6-19 years, and 26.7% were >19 years of age. Males accounted for 52% of the cases. Of the 118 cases with a known clinical outcome, 0.8% had no effect, 80.5% had minor effects, and 18.6% had moderate effects. Counties along the Gulf Coast accounted for 72.3% of the calls. This information can be used to identify those portions of the population most at need of education regarding the prevention and treatment of jellyfish stings. PMID:16696293

Forrester, M B

2006-04-01

70

Isolation and characterization of lethal proteins in nematocyst venom of the jellyfish Cyanea nozakii Kishinouye  

Microsoft Academic Search

Cyanea nozakii Kishinouye, a jellyfish widely distributed in coastal areas of China, has garnered attention because of its stinging capacity and the resulting public health hazard. We used a recently developed technique to extract jellyfish venom from nematocysts; the present study investigates the lethality of C. nozakii venom. The nematocyst contents were extremely toxic to the grass carp, Ctenopharyngodon idellus,

Jinhua Feng; Huahua Yu; Cuiping Li; Ronge Xing; Song Liu; Lin Wang; Shengbao Cai; Pengcheng Li

2010-01-01

71

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...

72

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

73

An examination of the cardiovascular effects of an ‘Irukandji’ jellyfish, Alatina nr mordens  

Microsoft Academic Search

Irukandji syndrome is usually characterized by delayed severe abdominal, back and chest pain associated with autonomic effects including diaphoresis, hypertension and, in severe cases, myocardial injury and pulmonary oedema. It is most often associated with envenoming by the jellyfish Carukia barnesi, but a number of other jellyfish, including Alatina mordens, are now known to produce Irukandji syndrome. In the present

Kelly L. Winter; Geoffrey K. Isbister; Jennifer J. Schneider; Nicki Konstantakopoulos; Jamie E. Seymour; Wayne C. Hodgson

2008-01-01

74

Jellyfish-Venom-Induced Deep Venous ThrombosisA Case Report  

Microsoft Academic Search

The authors describe a case of jellyfish sting that resulted in deep venous thrombosis of the leg and thigh of a thirty-five-year-old healthy man. The authors found no mention of this complication from jellyfish sting in the literature. Successful treatment measures are described.

K. Al-Ebrahim; M. Z. Tahir; M. Rustom; H. Shafei

1995-01-01

75

Modeling jellyfish Pelagia noctiluca transport and stranding in the Ligurian Sea.  

PubMed

Jellyfish blooms are generally attributed to a biological response to the environment, neglecting the role of transport patterns in redistributing existing populations. Here, we use high-resolution (1.25km) ocean modeling to examine the role of transport in the onshore arrival and abundance of the pelagic stinging jellyfish Pelagia noctiluca on the Ligurian Sea coast. Jellyfish are modeled as Lagrangian particles with a 0-300-m diel vertical migration typical of P. noctiluca. Over the course of a year, onshore arrivals are not restricted to the summer. Arrivals are concentrated at capes, but abundance can reach maxima in bays and in the lee of capes. Two factors impact jellyfish arrivals at the coast: the position of the Northern Current and the wind. A comparison of summer 2006 and available onshore jellyfish observations suggests a correct capture of the main stranding events by the model. These results have implications for understanding long-term fluctuations. PMID:23490349

Berline, L; Zakardjian, B; Molcard, A; Ourmières, Y; Guihou, K

2013-03-08

76

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

77

A shift to parasitism in the jellyfish symbiont Symbiodinium microadriaticum.  

PubMed

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 the potential for virulence evolution in this widespread symbiosis. In one experimental treatment, vertical transmission of algae (parent to offspring) selected for symbiont cooperation, because symbiont fitness was tied to host reproduction. In the other treatment, horizontal transmission (infectious spread) decoupled symbiont fitness from the host, potentially allowing parasitic symbionts to spread. Fitness estimates revealed a striking shift to parasitism in the horizontal treatment. The horizontally transmitted algae proliferated faster within hosts and had higher dispersal rates from hosts compared to the vertical treatment, while reducing host reproduction and growth. However, a trade-off was detected between harm caused to hosts and symbiont fitness. Virulence trade-offs have been modelled for pathogens and may be critical in stabilising 'infectious' symbioses. Our results demonstrate the dynamic nature of this symbiosis and illustrate the potential ease with which beneficial symbionts can evolve into parasites. PMID:16615208

Sachs, Joel L; Wilcox, Thomas P

2006-02-22

78

Velarium control and visual steering in box jellyfish.  

PubMed

Directional swimming in the box jellyfish Tripedalia cystophora (cubozoa, cnidaria) is controlled by the shape of the velarium, which is a thin muscular sheet that forms the opening of the bell. It was unclear how different patterns of visual stimulation control directional swimming and that is the focus of this study. Jellyfish were tethered inside a small experimental tank, where the four vertical walls formed light panels. All four panels were lit at the start of an experiment. The shape of the opening in the velarium was recorded in response to switching off different combinations of panels. We found that under the experimental conditions the opening in the velarium assumed three distinct shapes during a swim contraction. The opening was (1) centred or it was off-centred and pocketed out either towards (2) a rhopalium or (3) a pedalium. The shape of the opening in the velarium followed the direction of the stimulus as long as the stimulus contained directional information. When the stimulus contained no directional information, the percentage of centred pulses increased and the shape of the off-centred pulses had a random orientation. Removing one rhopalium did not change the directional response of the animals, however, the number of centred pulses increased. When three rhopalia were removed, the percentage of centred pulses increased even further and the animals lost their ability to respond to directional information. PMID:23417442

Petie, Ronald; Garm, Anders; Nilsson, Dan-Eric

2013-02-16

79

Guillain-Barré syndrome after a jellyfish sting.  

PubMed

This is the case of a jellyfish sting associated with the rare development of Guillain-Barré syndrome. The patient, a 66-year-old woman, was stung by a jellyfish on the right thigh while swimming in the Atlantic Ocean, off Charleston, SC. Ten days later, she developed low back and right thigh pain followed by progressive numbness and weakness in all extremities. These symptoms reached their peak in 30 days and slowly began to improve. Initial neurologic examination showed areflexia, weakness, absent vibration and position sense, and hyperesthesia to pin and light touch in the mid to distal region of all four extremities. Serial electromyography and nerve conductions were consistent with an improving predominantly demyelinating polyneuropathy. Spinal fluid analysis showed no cells, elevated protein (108), gammaglobulin 6 (normal less than 5.4), and immunoglobulin G 8.2 (normal less than 6). The only treatment was gabapentin for neuropathy pain. The patient made an excellent recovery in less than 1 year with minimal residual numbness in both thumbs, index fingers, and middle toes. PMID:22361521

Devere, Ronald

2011-06-01

80

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

81

A new record of the freshwater jellyfish Craspedacusta sowerbii Lankester, 1880 (Hydrozoa) in Southeastern Anatolia (Turkey)  

NASA Astrophysics Data System (ADS)

We report the first record of the invasive freshwater jellyfish Craspedacusta sowerbii Lankester in Kralkizi Dam Lake, Southeastern Anatolia, Turkey. The medusa was found only in August, 2008 when average surface water temperatures were 26.9°C.

Bekleyen, Aysel; Varol, Memet; Gokot, Bulent

2011-03-01

82

Review of Fatal and Severe Cases of Box Jellyfish Envenomation in Thailand.  

PubMed

The study aimed to describe severe and fatal cases of box jellyfish stings in Thailand. Medical records were reviewed and patients, relatives, health staffs, and witnesses were interviewed. The pictures of suspected box jellyfish were sent via e-mail to experts in the toxic jellyfish network for further identification. There were at least 8 cases of box jellyfish envenomation, with 4 fatal and 4 near-fatal cases. There were an equal number of male and female patients from 4 to 26 years of age. In each case, there was immediate severe pain followed by systemic reactions. Immediately after exposure to the sting, 7 victims collapsed experiencing severe pain at the tentacle marks, respiratory failure, and cardiac arrest. All patients had tentacle marks on their bodies. In none of the fatal cases was vinegar applied to the tentacle marks as first aid, but 3 out of the 4 near-fatal cases were treated with a vinegar application. PMID:22743852

Thaikruea, Lakkana; Siriariyaporn, Potjaman; Wutthanarungsan, Rochana; Smithsuwan, Punnarai

2012-06-28

83

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.

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

84

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

85

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

86

Stranding events provide indirect insights into the seasonality and persistence of jellyfish medusae (Cnidaria: Scyphozoa)  

Microsoft Academic Search

It is becoming increasingly evident that jellyfish (Cnidaria: Scyphozoa) play an important role within marine ecosystems,\\u000a yet our knowledge of their seasonality and reproductive strategies is far from complete. Here, we explore a number of life\\u000a history hypotheses for three common, yet poorly understood scyphozoan jellyfish (Rhizostoma octopus; Chrysaora hysoscella; Cyanea capillata) found throughout the Irish and Celtic Seas. Specifically,

Jonathan David Roy Houghton; Thomas K. Doyle; John Davenport; Martin K. S. Lilley; Rory P. Wilson; Graeme C. Hays

2007-01-01

87

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

88

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

89

Acoustic survey of a jellyfish-dominated ecosystem (Mljet Island, Croatia)  

Microsoft Academic Search

Acoustic techniques have been proposed as a new tool to assess jellyfish populations. However, the presence of mixed echoes\\u000a from jellyfish and other organisms that share their distribution often prevent accurate estimates of their abundance and distribution\\u000a being obtained. The isolated population of Aurelia inhabiting the Veliko Jezero (Big Lake-BL) of Mljet Island, in the South Adriatic Sea, offered a

G. Alvarez Colombo; A. Benovi?; A. Malej; D. Lu?i?; T. Makovec; V. Onofri; M. Acha; A. Madirolas; H. Mianzan

2009-01-01

90

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

91

Extract from the zooxanthellate jellyfish Cotylorhiza tuberculata modulates gap junction intercellular communication in human cell cultures.  

PubMed

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-7 and HEKa cells. A significantly higher cytotoxicity and GJIC enhancement in MCF-7 compared to HEKa cells was recorded. A putative action mechanism for the anticancer bioactivity through the modulation of GJIC has been hypothesized and its nutraceutical and pharmaceutical potential was discussed. PMID:23697954

Leone, Antonella; Lecci, Raffaella Marina; Durante, Miriana; Piraino, Stefano

2013-05-22

92

Complete mitochondrial genome of the jellyfish, Chrysaora quinquecirrha (Cnidaria, Scyphozoa).  

PubMed

Abstract We sequenced 16,775?bp of the linear mitochondrial DNA of the jellyfish Chrysaora quinquecirrha and characterized them. C. quinquecirrha has 13 protein-coding genes (PCGs), 16S rRNA and 12S rRNA with 3 tRNAs (tRNA-Leu, tRNA-Ser(TGA), tRNA-Met) as shown in Aurelia sp. nov. Both have another two PCGs such as helicase and orf363 with telomeres at both ends. The PCGs of C. quinquecirrha shows anti-G bias on 2nd and 3rd positions of PCGs as well as anti-C bias on 1st and 3rd positions of PCGs. PMID:23488924

Hwang, Dae-Sik; Park, Eunji; Won, Yong-Jin; Lee, Woo-Jin; Shin, Kyoungsoon; Lee, Jae-Seong

2013-03-14

93

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

94

Multiple organ dysfunction: a delayed envenomation syndrome caused by tentacle extract from the jellyfish Cyanea capillata.  

PubMed

The delayed jellyfish envenomation syndrome (DJES) with serious multiple organ dysfunction or systemic damages, generally developed 2 h after jellyfish stings, deserves special attention for it is very meaningful to the clinical interventions. To set up a DJES model as well as to obtain more details about its process, an integrative approach, including clinical chemistry, pathology and immunohistochemistry, was conducted to simultaneously monitor the effects of tentacle extract (TE) from the jellyfish Cyanea capillata on the vital target organs (heart, lung, liver and kidney). Our results showed that the TE from C. capillata could induce diverse toxic effects on these organs, among which the liver and kidney injuries seemed to be more serious than cardiopulmonary injuries and might be the leading causes of death in rats with DJES. In summary, we have established a DJES model with multiple organ dysfunction, which could facilitate the research on its underlying mechanism as well as the development of specific prevention or therapy strategies against jellyfish envenomation. The application of this model suggested that the possible mechanism of DJES might be attributed to the synergy of cytotoxicity, vasoconstriction effect and other specific target organ toxicities of jellyfish venom. PMID:23151380

Wang, Beilei; Zhang, Lin; Zheng, Jiemin; Wang, Qianqian; Wang, Tao; Lu, Jia; Wen, Xiaojuan; Zhang, Bo; Liu, Guoyan; Zhang, Wei; Xiao, Liang; Zhang, Liming

2012-11-11

95

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

96

Effects of anthropogenic disturbance on the abundance and size of epibenthic jellyfish Cassiopea spp.  

PubMed

Jellyfish blooms in pelagic systems appear to be increasing on a global scale because of anthropogenic impacts, but much less is known about the link between human activities and epibenthic jellyfish abundance. The aim of this study was to investigate whether the epibenthic jellyfish, Cassiopea spp., were found in greater abundance, and attained larger sizes, in coastal habitats adjacent to high human population densities compared to sites adjacent to uninhabited areas on Abaco Island, Bahamas. Cassiopea spp. were found to be significantly more dense and larger in areas with high human population densities. Ambient nutrient levels and nutrient content of seagrass were elevated in high human population density sites, and may be one mechanism driving higher abundance and size of Cassiopea spp. Cassiopea spp. may have important effects on community structure and ecosystem function in critical coastal ecosystems (e.g., seagrass beds), and their impacts warrant further study. PMID:21486672

Stoner, Elizabeth W; Layman, Craig A; Yeager, Lauren A; Hassett, Heather M

2011-04-12

97

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.

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

2013-01-01

98

Changes in the small-jellyfish community in recent decades in Jiaozhou Bay, China  

NASA Astrophysics Data System (ADS)

We used long term monitoring data to evaluate changes in abundance and species dominance of small-jellyfish (collected with zooplankton net whose bell diameter was less than 5 cm) between 1991 and 2009 in the Jiaozhou Bay, China. Zooplankton samples were vertically towed with conical plankton net from near-bottom to surface, identified microscopically, and mapped in time-space using Grapher 7.0 and Surfer 8.0. Results show that the abundance of small-jellyfish throughout the bay had been increasing during 2001-2009 on average of 15.2 ind./m3, almost 5 times higher than that between 1991 and 2000. The occurrence of peak abundance shifted from spring to summer after 2000, and two peaks appeared in spring and summer, respectively, after 2005. Both the abundance and the frequency of blooms of small-jellyfish increased after 2000 in the bay. In addition, the biodiversity of jellyfish has increased significantly in recent years with a change in dominant species. Several new dominant species appeared after 2000, including Rathkae octopunctata in winter, Phialidium hemisphaericum in spring, summer, and autumn, Phialucium carolinae in spring, and Pleurobrachia globosa in summer and autumn, while some previous dominant species throughout the 1990s ( Eirene ceylonensis, Zanclea costata, Lovenella assimilis, and Muggiaea atlantica ) were no longer dominant after 2000. The abundance of small-jellyfish was positively correlated with the density of dinoflagellates, and the abundance of zooplankton. We believe that the changes in smalljellyfish abundance and species composition were the result of eutrophication, aquaculture and coastal construction activities around the bay. Concurrently, seawater warming and salinity decrease in recent decades promoted the growth and reproduction of small-jellyfish in the bay.

Sun, Song; Li, Yinghong; Sun, Xiaoxia

2012-07-01

99

The role of hyperiid parasites as a trophic link between jellyfish and fishes.  

PubMed

The trophic interactions between the scyphozoan medusa Chrysaora plocamia and the palm ruff Seriolella violacea were investigated off northern Chile and showed that large numbers of hyperiid amphipods parasitizing the medusa may channel energy back to the fishes, which feed on the parasites. The biomass of hyperiids eaten by the fish was a function of the biomass of hyperiids parasitizing the medusa. This temporally available food supply may enhance fish recruitment. The large number of hyperiids parasitizing diverse jellyfish species represents a missing trophic link in current efforts to understand the effects of jellyfish blooms on marine food webs. PMID:23020568

Riascos, J M; Vergara, M; Fajardo, J; Villegas, V; Pacheco, A S

2012-09-14

100

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.

2012-03-01

101

Distribution of moon jellyfish Aurelia aurita in relation to summer hypoxia in Hiroshima Bay, Seto Inland Sea  

NASA Astrophysics Data System (ADS)

Biological and physical surveys were conducted in order to investigate the relationship between environmental conditions and the distribution of moon jellyfish Aurelia aurita in Hiroshima Bay, western Seto Inland Sea, Japan. Moon jellyfish and ichthyoplankton were collected at 13 stations in Hiroshima Bay during monthly surveys from July to September in 2006 and 2007. Surface temperature in 2006 was significantly lower during the August and September cruises and surface salinity was lower during all cruises than in 2007. Moon jellyfish was the most dominant gelatinous plankton collected, accounting for 89.7% in wet weight. Mean moon jellyfish abundance in 2006 was higher than that in 2007 from July through September, with significant inter-year differences for July and September. Variability in precipitation and nutritional input from the Ohta River, northernmost part of Hiroshima Bay, were suggested as possible factors affecting the inter-annual variability in moon jellyfish abundance in the coastal areas of northern Hiroshima Bay. Moon jellyfish were more abundant in the coastal areas of northern Hiroshima Bay, where the dissolved oxygen (DO) concentration was lower, while low in the central part of the bay. Japanese anchovy Engraulis japonicus eggs were most dominant (58.1% in number) among the ichthyoplankton and were abundant in the central area of Hiroshima Bay. Explanatory analysis was conducted to detect possible effects of environmental conditions on the abundance of moon jellyfish and Japanese anchovy eggs during the summer months in Hiroshima Bay. Of the environmental conditions tested (temperature, salinity and DO of surface and bottom layers at each sampling station), bottom DO had the most significant effect on the moon jellyfish abundance: there was a negative correlation between the bottom DO and the moon jellyfish abundance in Hiroshima Bay during summer.

Shoji, Jun; Kudoh, Takaya; Takatsuji, Hideyuki; Kawaguchi, Osamu; Kasai, Akihide

2010-02-01

102

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

National Technical Information Service (NTIS)

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 ...

D. B. Spangenberg

1991-01-01

103

Diversification of animal venom peptides-were jellyfish amongst the first combinatorial chemists?  

PubMed

An ocean of data: Huge numbers of protein toxins are found in animal venoms. This diversity is widely believed to have arisen by gene duplication events. However, recent data now challenges this tradition view. Here we highlight how jellyfish could hold the key to unravelling toxin diversification, with a view towards future combinatorial biosynthesis of toxin libraries. PMID:23821453

Starcevic, Antonio; Long, Paul F

2013-07-02

104

Learning from jellyfish: Fluid transport in muscular pumps at intermediate Reynolds numbers  

NASA Astrophysics Data System (ADS)

Biologically inspired hydrodynamic propulsion and maneuvering strategies promise the advancement of medical implants and minimally invasive clinical tools. We have chosen juvenile jellyfish as a model system for investigating fluid dynamics and morphological properties underlying fluid transport by a muscular pump 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 an artificial jellyfish, that is, a jellyfish-inspired construct of a flexible plastic sheet actuated by a monolayer of rat cardiomyocytes. The main challenges here are (1) to derive a body shape and deformation suitable for effective fluid transport under physiological conditions, (2) to understand the mechanical properties of the muscular film and derive a design capable of the desired deformation, (3) to master the proper alignment and timely contraction of the muscle component needed to achieve the desired deformation, and (4) to evaluate the performance of the design.

Nawroth, Janna; Dabiri, John

2010-11-01

105

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

PubMed

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

2013-10-07

106

Electrophysiological and hemolytic activity elicited by the venom of the jellyfish Cassiopea xamachana  

Microsoft Academic Search

In this study, we determined hemolysis activity in human and sheep erythrocytes, and characterized the electrical responses in Xenopus oocyte membrane elicited by the venom of the jellyfish Cassiopea xamachana (Cx). The Cx venom produced hemolysis in both species, being more potent on human red cells. The electrophysiological study showed that the Cx venom elicited three different responses in the

Mónica Torres; Manuel B. Aguilar; Andrés Falcón; Lenin Sánchez; Faisal F. Y. Radwan; Joseph W. Burnett; Edgar P. Heimer-de la Cotera; Rogelio O. Arellano

2001-01-01

107

Lichen planus-like eruption resulting from a jellyfish sting: a case report  

PubMed Central

Introduction Contact with a jellyfish can cause a wide variety of conditions, ranging from cutaneous eruption to fatal cardiovascular and respiratory collapse. Cutaneous features can be both acute and chronic. We report a case of persistent lichen planus-like eruption in a young boy after a jellyfish sting, a hitherto unreported occurrence. Case presentation A 15-year-old boy presented with multiple lichen planus-like violaceous papules over the lower part of his left thigh on the anterior aspect and also over the patellar region. He had a history of a jellyfish sting over his lower limbs incurred while bathing in the sea four weeks prior to presentation. Histopathology revealed a predominantly perivascular mononuclear cell infiltrate immediately beneath the dermoepidermal junction underneath the hyperplastic epidermis. The lesions significantly subsided with topical corticosteroid application. Conclusion This case report demonstrates a new variant of chronic cutaneous change following a jellyfish sting. We report it because of its uniqueness and we believe that physicians should be aware of the possibility of an aquatic animal-induced disease when dealing with lesions with lichen planus-like morphology.

2009-01-01

108

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

109

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.

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

2008-01-01

110

Venom ontogeny, diet and morphology in Carukia barnesi, a species of Australian box jellyfish that causes Irukandji syndrome  

Microsoft Academic Search

Venom profiles of two age groups of the medically important Australian box jellyfish Carukia barnesi [Southcott, R.V., 1967. Revision of some Carybdeidae (Scyphozoa, Cubomedusae), including description of jellyfish responsible for the ‘Irukandji’ syndrome. Aust. J. Zool. 15, 651–657] were compared. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis revealed differences in protein banding of tentacular venom between immature and mature animals. This correlates

Avril H. Underwood; Jamie E. Seymour

2007-01-01

111

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

112

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

2006-07-14

113

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

2011-10-01

114

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

115

[Marine envenomation by box-jellyfish in a tourist in Cambodia].  

PubMed

We report a case of box-jellyfish related envenomation in a 40 year old tourist that occurred in Sihanoukville, Cambodia, in the Gulf of Thailand. Symptoms that appeared within a few minutes associated intense pain, hand edema and large edematous and erythematous flagellations in the stung skin areas. Antibiotics and corticosteroids were delivered. Inflammatory signs and skin lesions disappeared within 15 days followed by crusts then scars. Jellyfish at risk for humans are generally found in tropical seas and their geographic distribution seems to spread. As it is difficult to prevent this kind of accident, travelers should be aware of the first acts to perform, such as appropriate cleaning of the wound, the interest of vinegar usage, the administration of analgesics and corticosteroids in case of significant inflammatory signs. PMID:24072422

Bellaud, G; Epelboin, L; Henn, A; Perignon, A; Bricaire, F; Caumes, E

2013-09-26

116

Prolonged urinary incontinence and biliary dyskinesia following abdominal contact with jellyfish tentacles.  

PubMed

A 16-year-old girl was seriously stung on her abdomen by a jellyfish as she jumped on her small surfboard. She and her mother identified the animal from photographs as Chrysaora fuscescens. Within several minutes the girl developed a massive abdominal cutaneous eruption composed of hundreds of punctuate erythematous papules and macules, which persisted for 5 to 7 days. Persistent urinary incontinence and biliary dyskinesia appeared over the following night. It is theorized that a systemic uptake of venom occurred percutaneously after contact of the jellyfish tentacles with her abdominal skin. The result was an injury to the urinary and biliary bladders. This is the first case report of such sequellae after topical contact with a marine animal. The causal relationship of these abnormalities with the sting is suggested by their temporal association. The gallbladder disorder required surgical intervention, but spontaneous resolution of the urinary bladder dysfunction occurred within 20 months. PMID:17078314

Burnett, Joseph W

2006-01-01

117

Extension of methods for jellyfish and ctenophore trophic ecology to large-scale research  

Microsoft Academic Search

Science has rapidly expanded its frontiers with new technologies in the 20th Century. Oceanography now is studied routinely\\u000a by satellite. Predictive models are on global scales. At the same time, blooms of jellyfish and ctenophores have become problematic,\\u000a especially after 1980. Although we have learned a great deal about gelatinous zooplankton ecology in the 20th Century on local\\u000a scales, we

Jennifer E. Purcell

118

Extension of methods for jellyfish and ctenophore trophic ecology to large-scale research  

Microsoft Academic Search

Science has rapidly expanded its frontiers with new technologies in the 20th Century. Oceanography now is studied routinely\\u000a by satellite. Predictive models are on global scales. At the same time, blooms of jellyfish and ctenophores have become problematic,\\u000a especially after 1980. Although we have learned a great deal about gelatinous zooplankton ecology in the 20th Century on local\\u000a scales, we

Jennifer E. Purcell

2009-01-01

119

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

120

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

Microsoft Academic Search

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 48h LC50 values were 123.1, 581.6, and 716.3?g\\/mL, respectively. Of the

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

2005-01-01

121

Partial characterization of the hemolytic activity of the nematocyst venom from the jellyfish Cyanea nozakii Kishinouye  

Microsoft Academic Search

Using a recently developed technique to extract jellyfish venom from nematocysts, the present study investigated the hemolytic activity of Cyanea nozakii Kishinouye nematocyst venom on chicken erythrocytes. Venom extract caused a significant concentration-dependent hemolytic effect. The extract could retain its activity at ?80°C but was unstable when kept at 4°C and ?20°C for 2 days. The hemolytic activity was inhibited

Jinhua Feng; Huahua Yu; Ronge Xing; Song Liu; Lin Wang; Shengbao Cai; Pengcheng Li

2010-01-01

122

Apoptosis induced by box jellyfish ( Chiropsalmus Quadrigatus) toxin in glioma and vascular endothelial cell lines  

Microsoft Academic Search

This study was made to investigate whether Chiropsalmus Quadrigatus toxins (CqTX), which isolated from box jellyfish C. Quadrigatus venom, could induce apoptosis in human U251 and rat C6 malignant glioma cells and transformed vascular endothelial ECV 304 cell lines. Cell viability was estimated by MTT assay. Apoptosis was evaluated using TdT (terminal deoxynucleotidyl transferase)-mediated dUTP nick-end labeling (TUNEL) method and

Lian-Kun Sun; Yoshihiko Yoshii; Akio Hyodo; Hideo Tsurushima; Atsushi Saito; Tsuyoshi Harakuni; Ya-Ping Li; Masatoshi Nozaki; Nobuya Morine

2002-01-01

123

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

Microsoft Academic Search

In this study, hemolytic activity of venom from the jellyfish Rhopilema esculentum Kishinouye and some factors affecting it were assayed. The HU50 of R. esculentum full venom (RFV) against chicken erythrocytes was 3.40?g\\/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

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

2007-01-01

124

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

Microsoft Academic Search

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. Zn2+, Mg2+, and Mn2+ in sodium phosphate buffer (0.02M, pH 8.0) could increase protease activity. Mn2+ had

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

2005-01-01

125

Isolation and characterization of venom from nematocysts of jellyfish Rhopilema esculentum Kishinouye  

Microsoft Academic Search

The present work is the first report of the biochemical characterization of the venom from nematocysts of the jellyfish Rhopilema esculentum Kishinouye. The nematocysts were isolated by autolysis and centrifugation and separated by flow cytometry. Four types of\\u000a nematocysts were identified: mastigophores, euryteles, and atrichous and holotrichous isorhiza. SDS-PAGE and amino acid analyses\\u000a demonstrated that most of the proteins in

Jinhua Feng; Huahua Yu; Cuiping Li; Ronge Xing; Song Liu; Lin Wang; Shengbao Cai; Pengcheng Li

2009-01-01

126

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

Microsoft Academic Search

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\\u000a venom are not applicable due to the low concentration of the compounds dissolved. Although the recovery efficiency and the\\u000a total venom obtained

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

2009-01-01

127

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

Microsoft Academic Search

Sediment cores from Jellyfish Lake were processed under an inert atmos phcre and the pore waters extracted and analyzed for the following parameters: pH, titration alkalinity (TA), Cl-, H4Si04, POd3-, NH4+, Ca2+, Mg2+, SOd2-, and H2S. Additionally, in one set of pore-water samples (core lo), the 613C of the X0, was also determined. The TA, H4Si04, POd3-, NH;+, and H,S

Robert M. Lent; William C. Burnett; Philip Chin; William M. Landing; William H. Orem; John M. McArthur

1996-01-01

128

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

129

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.

2009-01-01

130

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

2013-02-15

131

Feeding currents of the upside down jellyfish in the presence of background flow.  

PubMed

The upside-down jellyfish (Cassiopea spp.) is an ideal organism for examining feeding and exchange currents generated by bell pulsations due to its relatively sessile nature. Previous experiments and numerical simulations have shown that the oral arms play an important role in directing new fluid into the bell from along the substrate. All of this work, however, has considered the jellyfish in the absence of background flow, but the natural environments of Cassiopea and other cnidarians are dynamic. Flow velocities and directions fluctuate on multiple time scales, and mechanisms of particle capture may be fundamentally different in moving fluids. In this paper, the immersed boundary method is used to simulate a simplified jellyfish in flow. The elaborate oral arm structure is modeled as a homogenous porous layer. The results show that the oral arms trap vortices as they form during contraction and expansion of the bell. For constant flow conditions, the vortices are directed gently across the oral arms where particle capture occurs. For variable direction flows, the secondary structures change the overall pattern of the flow around the bell and appear to stabilize regions of mixing around the secondary mouths. PMID:22936161

Hamlet, Christina L; Miller, Laura A

2012-08-31

132

The Jellyfish: smart electro-active polymers for an autonomous distributed sensing node  

NASA Astrophysics Data System (ADS)

The US Navy has recently placed emphasis on deployable, distributed sensors for Force Protection, Anti-Terrorism and Homeland Defense missions. The Naval Undersea Warfare Center has embarked on the development of a self-contained deployable node that is composed of electro-active polymers (EAP) for use in a covert persistent distributed surveillance system. Electro-Active Polymers (EAP) have matured to a level that permits their application in energy harvesting, hydrophones, electro-elastic actuation and electroluminescence. The problem to resolve is combining each of these functions into an autonomous sensing platform. The concept presented here promises an operational life several orders of magnitude beyond what is expected of a Sonobuoy due to energy conservation and harvesting, and at a reasonable cost. The embodiment envisioned is that of a deployed device resembling a jellyfish, made in most part of polymers, with the body encapsulating the necessary electronic processing and communications package and the tentacles of the jellyfish housing the sonar sensors. It will be small, neutrally buoyant, and will survey the water column much in the manner of a Cartesian Diver. By using the Electro-Active Polymers as artificial muscles, the motion of the jellyfish can be finely controlled. An increased range of detection and true node autonomy is achieved through volumetric array beamforming to focus the direction of interrogation and to null-out extraneous ambient noise.

Blottman, John B.; Richards, Roger T.

2006-06-01

133

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

134

THE JELLYFISH AURELIA AURITA (CNIDARIA: SCYPHOMEDUSAE): ITS LIFE HISTORY STRATEGY, MIGRATION ACTIVITY AND ITS IMPACT ON THE ZOOPLANKTON COMMUNITY OF SUEZ CANAL, EGYPT  

Microsoft Academic Search

Suez Canal is the main connecting link between the Red Sea in the south and the Mediterranean in the north. It crosses different lakes on its route from Port Said on the Mediterranean Sea to Port Suez on the Red Sea. Jellyfishes form a major part of the macro- plankton of the canal. The role of jellyfishes in general and

HAMED A. EL-SEREHY

135

Effects of collagen and collagen hydrolysate from jellyfish umbrella on histological and immunity changes of mice photoaging.  

PubMed

Jellyfish collagen (JC) was extracted from jellyfish umbrella and hydrolyzed to prepare jellyfish collagen hydrolysate (JCH). The effects of JC and JCH on UV-induced skin damage of mice were evaluated by the skin moisture, microscopic analyses of skin and immunity indexes. The skin moisture analyses showed that moisture retention ability of UV-induced mice skin was increased by JC and JCH. Further histological analysis showed that JC and JCH could repair the endogenous collagen and elastin protein fibers, and could maintain the natural ratio of type I to type III collagen. The immunity indexes showed that JC and JCH play a role in enhancing immunity of photoaging mice in vivo. JCH showed much higher protective ability than JC. These results suggest that JCH as a potential novel antiphotoaging agent from natural resources. PMID:23344251

Fan, Jian; Zhuang, Yongliang; Li, Bafang

2013-01-17

136

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

137

Isolation and in vitro partial characterization of hemolytic proteins from the nematocyst venom of the jellyfish Stomolophus meleagris.  

PubMed

Jellyfish venom contains various toxins and can cause itching, edema, muscle aches, shortness of breath, blood pressure depression, shock or even death after being stung. Hemolytic protein is one of the most hazardous components in the venom. The present study investigated the hemolytic activity of the nematocyst venom from jellyfish Stomolophus meleagris. Anion exchange chromatography, DEAE Sepharose Fast Flow, and gel filtration chromatography, Superdex200 had been employed to isolate hemolytic proteins from the nematocyst venom of jellyfish S. meleagris. Hemolysis of chicken red blood cells was used to quantify hemolytic potency of crude nematocyst venom and chromatography fractions during the purification process. Native-PAGE profile displayed one protein band in the purified hemolytic protein (SmTX); however, two protein bands with apparent molecular weights of ?45kDa and 52kDa were observed in the reducing SDS-PAGE analysis. Approximately 70?g/mL of SmTX caused 50% hemolysis (HU50) of the erythrocyte suspension. The hemolytic activity of SmTX was shown to be temperature and pH dependent, with the optimum temperature and pH being 37°C and pH 5.0. The present study is the first report of isolation and partial characterization of hemolytic proteins from the nematocyst venom of the jellyfish S. meleagris. The mechanism of the hemolytic activity of SmTX is not clear and deserves further investigation. PMID:23603477

Li, Rongfeng; Yu, Huahua; Xing, Ronge; Liu, Song; Qing, Yukun; Li, Kecheng; Li, Bing; Meng, Xiangtao; Cui, Jinhui; Li, Pengcheng

2013-04-17

138

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

Microsoft Academic Search

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 L61×36. Of the seven controllable independent variables, incubated temperature and phenylmethylsulfonyl fluoride (PMSF) had strongest effect on the hemolytic activity.

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

2007-01-01

139

Ontogeny of swimming speed, schooling behaviour and jellyfish avoidance by Japanese anchovy Engraulis japonicus.  

PubMed

The ontogeny of swimming speed, schooling behaviour and jellyfish avoidance was studied in hatchery-reared Japanese anchovy Engraulis japonicus to compare its life-history strategy with two other common pelagic fishes, jack mackerel Trachurus japonicus and chub mackerel Scomber japonicus. Cruise swimming speed of E. japonicus increased allometrically from 1·4 to 3·9 standard length (L(S) ) per s (L(S) s(-1) ) from early larval to metamorphosing stage. Burst swimming speed also increased from 6·1 to 28 L(S) s(-1) in these stages. Cruise speed was inferior to that of S. japonicus, as was burst speed to that of T. japonicus. Engraulis japonicus larvae were highly vulnerable to predation by moon jellyfish Aurelia aurita and were readily eaten until they reached 23 mm L(S) , but not at 26 mm L(S) . Schooling behaviour (indicated by parallel swimming) started at c. 17 mm L(S) . Average distance to the nearest neighbour was shorter than values reported in other pelagic fishes. The relatively low predator avoidance capability of E. japonicus may be compensated for by their transparent and thus less conspicuous body, in addition to their early maturation and high fecundity. PMID:21539545

Masuda, R

2011-04-04

140

An Experimental Investigation of the Feeding Currents Generated by Upside-Down Jellyfish  

NASA Astrophysics Data System (ADS)

The flow characteristics of oblate medusan swimmers such as the moon jellyfish (Aurelia) have been examined to understand the bio-fluid mechanics of feeding via unsteady propulsion (see Dabiri et al., J. Exp. Biol., 2005). The upside-down jellyfish (Cassiopea) differs from the commonly observed swimming forms of scyphomedusae in that it is naturally found adhered to the muddy bottoms of shallow ocean waters. While they swim when disturbed, these organisms prefer to otherwise attach their bell surface to the floor and direct their oral arms upwards. Prey capture is accomplished by pulsatile contractions of the bell. The flow generated by the unsteady pulsations is examined using a combination of DPIV and morphological measurements. The phase-averaged flow field closely resembles a blowing jet centered about the body, with fluid entrainment occurring near the bell surface. Reversed flow regions are identified during both the contraction and relaxation phases. The effect of changing bell diameter on the jet as well as the production of flow structures is investigated. A qualitative comparison of the flow field between these organisms and swimming medusae will be presented.

Santhanakrishnan, Arvind; Miller, Laura

2009-11-01

141

JetSum: SMA actuator based undersea unmanned vehicle inspired by jellyfish bio-mechanics  

NASA Astrophysics Data System (ADS)

Previously, we reported an undersea unmanned vehicle (UUV) termed as JetSum, inspired by the locomotion of medusa jellyfish, [12]. The propulsion of JetSum was based on shape memory alloy (SMA) wires replicating the contraction-relaxation cycle of natural jellyfish locomotion. In this paper, we report modified design of JetSum that addresses problems related to electrical isolation and power consumption. The modifications lead to significant improvement in functionality, providing implementation of a full continuous bell, bolstering critical sealing junctions, and reducing the overall power requirement. A LabVIEW controller program was developed to automate and optimize the driving of JetSum enabling reduction in power consumption for full contraction of SMA. JetSum locomotion in underwater conditions was recorded by using a high-speed camera and analyzed with image processing techniques developed in MatLab. The results show that JetSum was able to achieve velocity of 7 cm/s with power consumption of 8.94 W per cycle.

Bressers, Scott; Chung, Sanghun; Villanueva, Alex; Smith, Colin; Priya, Shashank

2010-03-01

142

A wake-based correlate of swimming performance in seven jellyfish species  

NASA Astrophysics Data System (ADS)

Animal-fluid interactions have been hypothesized as a principal selective pressure on the evolution of aquatic and aerial animals. However, attempts to discover the fluid dynamic mechanisms that dictate the fitness of an animal---or even to quantify `fitness'---have been limited by an inability to measure the fluid interactions of freely moving animals (i.e., in the absence of tethers or artificial water/wind currents) in comparative studies of multiple species with similar evolutionary histories. We used digital particle image velocimetry (DPIV) measurements to calculate wake kinetic energy, drag, and swimming speed of the seven co-occurring species of free-swimming jellyfish. Using this new data, we demonstrate that the swimming and foraging behavior are related to a robust fluid dynamic threshold between two distinct configurations of the wake vortices. The transition between the two wake vortex configurations is known as optimal vortex formation, because it maximizes the fluid dynamic thrust generated for a given energy input (Krueger and Gharib, Phys. Fluids 2003). By comparing the observed wake structures created by each jellyfish species with the optimal vortex configuration, we are able to predict their relative swimming efficiencies and proficiencies and to deduce their corresponding ecological niches.

Dabiri, John; Colin, Sean; Katija, Kakani; Costello, John

2009-11-01

143

Modeling and optimization of IPMC actuator for autonomous jellyfish vehicle (AJV)  

NASA Astrophysics Data System (ADS)

Ionomeric Polymer Metal Composite (IPMC) actuators generate high flexural strains at small voltage amplitudes of 2-5V. IPMCs bend toward the anode when a potential drop is applied across its thickness. The actuation mechanism is due to the motion of ions inside it; which requires a form of hydration to dissociate and mobilize the charges. In our group IPMCs are developed either water based or Ionic Liquid based which is also known as the dry IPMCs. This combination of small voltage requirement with operation in both dry and underwater conditions makes the IPMCs a viable alternative for an Autonomous Jellyfish Vehicle (AJV). In this study, we estimate the mechanical properties of IPMC actuator having curved geometry using FEM model to match the experimental deformation. We combine the results from an electric model to estimate charge accumulated on electrode surface with piezoelectric model to estimate stress due to this charge accumulation. In the last step, the results are integrated with a structural model to simulate the actuator deformation. We have designed an AJV with embedded IPMC actuators using these properties to achieve the curvature of relaxed and contracted Jellyfish (Aurelia Aurita). Bio-mimetic deformation profile was achieved by using structural mechanics of beams with large deformation with only application of +/- 0.8V to optimized beam within 8.1% error norm in relaxed state and 21.3% in contracted state, with only -0.24% to 0.26% maximum flexural strain at maximum curvature point in contracted state.

Joshi, Keyur B.; Akle, Barbar J.; Leo, Donald J.; Priya, Shashank

2011-03-01

144

Use of in vivo insert molding to form a jellyfish valve leaflet.  

PubMed

We developed an in vivo insert molding technique to form tissue-derived biomaterials into the desired shape, and with sufficient strength and durability, for use in artificial organs. Molds of acrylic resin with inserted velour cloth were implanted under the skin of goats to form a circular leaflet for a jellyfish valve. The valve leaflets were successfully produced in the molds after 17-60 days. Dense connective tissue covered the velour cloth, and loose connective tissue was formed within it. Tissue was radially formed from the hole in the mold. The tissue was simultaneously formed and shrunk. It is necessary to increase the connected portion between the tissue inside and outside the mold so that the tissue can completely cover the inserted materials without shrinkage. PMID:20618219

Kishi, Ayumi; Isoyama, Takashi; Saito, Itsuro; Miura, Hidekazu; Nakagawa, Hidemoto; Kouno, Akimasa; Ono, Toshiya; Inoue, Yusuke; Yamaguchi, Sachiko; Shi, Wei; Abe, Yusuke; Imachi, Kou; Noshiro, Makoto

2010-12-01

145

Complete mitochondrial genome of the moon jellyfish, Aurelia sp. nov. (Cnidaria, Scyphozoa).  

PubMed

Abstract We sequenced 16,971 bp of the linear mitochondrial DNA of the moon jellyfish Aurelia sp. nov. and characterized it by comparing with Aurelia aurita. They had 13 protein-coding genes (PCGs), 16S rRNA and 12S rRNA with three tRNAs (tRNA-Leu, tRNA-Ser(TGA), tRNA-Met). Both have another two PCGs, orf969 and orf324 with telomeres at both ends. After comparison of Aurelia sp. nov. with Aurelia aurita, we found low-protein similarity of orf969 (59%) and orf324 (75%), respectively, while the other 13 PCGs showed 80% to 98% protein similarities. PMID:23488923

Hwang, Dae-Sik; Park, Eunji; Won, Yong-Jin; Lee, Jae-Seong

2013-03-14

146

Evidence-based treatment of jellyfish stings in North America and Hawaii.  

PubMed

We performed a systematic review of the evidence supporting various treatments for envenomation by jellyfish (cnidarian) and related organisms in North America and Hawaii. Our review produced 19 pertinent primary articles. Current research demonstrates variable response to treatment, often with conflicting results according to species studied, which contributes to considerable confusion about what treatment is warranted and efficacious. Our review suggests that vinegar causes pain exacerbation or nematocyst discharge in the majority of species. Hot water and topical lidocaine appear more widely beneficial in improving pain symptoms and are preferentially recommended. Unfortunately, they may be difficult to obtain at the site of envenomation, such as the beach or diving sites. In these instances, removing the nematocysts and washing the area with saltwater may be considered. If the envenomation is thought to be due to the bluebottle (Physalia), vinegar may be beneficial. PMID:22677532

Ward, Nicholas T; Darracq, Michael A; Tomaszewski, Christian; Clark, Richard F

2012-06-06

147

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

2012-03-20

148

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

2009-03-18

149

Flow structure and transport characteristics of feeding and exchange currents generated by upside-down Cassiopea jellyfish.  

PubMed

Quantifying the flows generated by the pulsations of jellyfish bells is crucial for understanding the mechanics and efficiency of their swimming and feeding. Recent experimental and theoretical work has focused on the dynamics of vortices in the wakes of swimming jellyfish with relatively simple oral arms and tentacles. The significance of bell pulsations for generating feeding currents through elaborate oral arms and the consequences for particle capture are not as well understood. To isolate the generation of feeding currents from swimming, the pulsing kinematics and fluid flow around the benthic jellyfish Cassiopea spp. were investigated using a combination of videography, digital particle image velocimetry and direct numerical simulation. During the rapid contraction phase of the bell, fluid is pulled into a starting vortex ring that translates through the oral arms with peak velocities that can be of the order of 10 cm s(-1). Strong shear flows are also generated across the top of the oral arms throughout the entire pulse cycle. A coherent train of vortex rings is not observed, unlike in the case of swimming oblate medusae such as Aurelia aurita. The phase-averaged flow generated by bell pulsations is similar to a vertical jet, with induced flow velocities averaged over the cycle of the order of 1-10 mm s(-1). This introduces a strong near-horizontal entrainment of the fluid along the substrate and towards the oral arms. Continual flow along the substrate towards the jellyfish is reproduced by numerical simulations that model the oral arms as a porous Brinkman layer of finite thickness. This two-dimensional numerical model does not, however, capture the far-field flow above the medusa, suggesting that either the three-dimensionality or the complex structure of the oral arms helps to direct flow towards the central axis and up and away from the animal. PMID:22723475

Santhanakrishnan, Arvind; Dollinger, Makani; Hamlet, Christina L; Colin, Sean P; Miller, Laura A

2012-07-15

150

Partial purification and characterization of a novel neurotoxin and three cytolysins from box jellyfish ( Carybdea marsupialis ) nematocyst venom  

Microsoft Academic Search

This paper describes one neurotoxin and three cytolysins isolated from the venom of the Caribbean box jellyfish Carybdea marsupialis. To assess the cytolytic and neurotoxic activity of the nematocyst venom, several bioassays were carried out, and to evaluate\\u000a the effect of the toxin, the dose causing 50% lethality (LD50) was determined in vivo using sea crabs (Ocypode quadrata). The proteins

J. Sánchez-Rodríguez; E. Torrens; L. Segura-Puertas

2006-01-01

151

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

Microsoft Academic Search

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

Xiao Liang; Wang Beilei; Li Ying; Wang Qianqian; Liu Sihua; Wang Yang; Liu Guoyan; Lu Jia; Ye Xuting; Zhang Liming

2012-01-01

152

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.

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

2012-01-01

153

Design and development of bio-inspired underwater jellyfish like robot using ionic polymer metal composite (IPMC) actuators  

NASA Astrophysics Data System (ADS)

This study presents the design and development of an underwater Jellyfish like robot using Ionic Polymer Metal Composites (IPMCs) as propulsion actuators. For this purpose, IPMCs are manufactured in several variations. First the electrode architecture is controlled to optimize the strain, strain rate, and stiffness of the actuator. Second, the incorporated diluents species are varied. The studied diluents are water, formamide, and 1-ethyl-3-methyimidazolium trifluoromethanesulfonate (EmI-Tf) ionic liquid. A water based IPMC demonstrates a fast strain rate of 1%/s, but small peak strain of 0.3%, and high current of 200mA/cm2, as compared to an IL based IPMC which has a slow strain rate of 0.1%/s, large strain of 3%, and small current of 50mA/cm2. The formamide is proved to be the most powerful with a strain rate of approximately 1%/s, peak strain larger than 5%, and a current of 150mA/cm2. The IL and formamide based samples required encapsulation for shielding the diluents from being dissolved in the surrounding water. Two Jellyfish like robots are developed each with an actuator with different diluents. Several parameters on the robot are optimized, such as the input waveform to the actuators, the shape and material of the belly. The finesse ratio of the shape of the robotic belly is compared with biological jellyfish such as the Aurelia-Aurita..

Akle, Barbar; Najem, Joseph; Leo, Donald; Blottman, John

2011-03-01

154

Plastic Jellyfish.  

ERIC Educational Resources Information Center

|Presents an environmental science activity designed to enhance students' awareness of the hazards of plastic waste for wildlife in aquatic environments. Discusses how students can take steps to reduce the effects of plastic waste. (WRM)|

Moseley, Christine

2000-01-01

155

Stokesian Jellyfish  

NASA Astrophysics Data System (ADS)

Most studies into the swimming of microscopic organisms are directed at flagellated cells, ciliated bodies, or other biologically relevant models. However, biological systems need not be emulated in order to produce locomotion. We present here a proof-of-principle model for a closed bilayer vesicle swimming at low Reynolds number due to a prescribed physically-actuated shape change of the surface. By modulating the volume and membrane composition of the vesicle via osmotic or colloidal effects, the vesicle shapes change continuously in thermal equilibrium, leading to non-reciprocal deformation, and therefore swimming, if the proper conditions are satisfied.

Evans, Arthur; Spagnolie, Saverio; Lauga, Eric

2009-11-01

156

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

2006-07-15

157

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.

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

2013-01-01

158

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

159

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.

2012-01-01

160

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

PubMed

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

2013-08-30

161

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

PubMed

Aurelin is a 40-residue cationic antimicrobial peptide isolated from the mezoglea of a scyphoid jellyfish Aurelia aurita. Aurelin and its (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(10)-helix and two ?-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 ?-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(+)-channels. The obtained data permit to correlate the modest antibacterial properties and membrane activity of aurelin. PMID:23137541

Shenkarev, Zakhar O; Panteleev, Pavel V; Balandin, Sergey V; Gizatullina, Albina K; Altukhov, Dmitry A; Finkina, Ekaterina I; Kokryakov, Vladimir N; Arseniev, Alexander S; Ovchinnikova, Tatiana V

2012-11-05

162

Heavy metals affect regulatory volume decrease (RVD) in nematocytes isolated from the jellyfish Pelagia noctiluca.  

PubMed

The environmental contamination caused by heavy metals raises the question of their effect on biological systems. Among bio-indicators useful to monitor the toxicological effects of these chemicals, Cnidarians offer a unique model. Cnidarians possess highly specialized stinging cells, termed nematocytes, which respond to hyposmotic solution with well established homeostatic parameters as an acute osmotic phase (OP), leading to cell swelling, and then a slower regulatory volume decrease (RVD) phase, causing cell shrinkage. Here we report the effect of 65% artificial sea water (ASW) containing heavy metals, such as Cd, La, Co, Cu and Zn (concentrations comprised between 100 and 0.1 ?M) on both OP and RVD in nematocytes isolated from the jellyfish Pelagia noctiluca by 605 mM NaSCN plus 0.01 mM Ca(2+). The exposure of the cells to Co and La inhibited RVD but not OP. However, Cu, Cd and Zn prevented the OP in a dose-dependent manner and, hence, also the detection of RVD. These results suggest that, in isolated nematocytes, heavy metal pollutants impair RVD either directly or indirectly through interference with the OP, thus negating RVD. Although further studies need to clarify the exact mechanisms whereby heavy metals exert their toxicity, it is evident that nematocytes of Cnidarians could serve as a model for ecotoxicological investigations. PMID:23499922

Morabito, R; Marino, A; La Spada, G

2013-03-14

163

Downward particulate organic carbon export and jellyfish blooms in southeastern Hudson Bay  

NASA Astrophysics Data System (ADS)

A long-term sediment trap was deployed at 100 m (station AN03; 55°24?N; 77°55?W; water depth = 136 m) from October 2005 to August 2007 to monitor downward carbon export in southeastern Hudson Bay in the Canadian subarctic region. Elevated particulate organic carbon (POC) and total fluxes during fall 2005 and 2006 were the result of wind-induced resuspension of settled POC. The absence of a significant increase in POC fluxes in summer 2006 in contrast to summer 2007 suggests variation in the processes regulating carbon export in southeastern Hudson Bay. Large quantities of the holoplanktonic jellyfish Aglantha digitale were collected in the sediment trap during fall 2006 and summer 2007. The large collection of A. digitale during fall 2006 corresponds to the seasonal descent of the population, while the large abundance during summer 2007 remains unexplained. The increased POC fluxes in summer 2007 and the large occurrence of A. digitale in 2006 and 2007 may be early signs of environmental changes in southeastern Hudson Bay, however more sampling is needed to capture the variability of the ecosystem.

Lalande, Catherine; Fortier, Louis

2011-12-01

164

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

2010-03-01

165

Cytotoxicity of the venom from the nematocysts of jellyfish Cyanea nozakii Kishinouye.  

PubMed

In this article, the cytotoxicity of the venom from the nematocysts of jellyfish Cyanea nozakii Kishinouye on human hepatoma cells (Bel-7402, SMMC-7721) and human colon cancer cells (H630) was investigated first. Of the three kinds of cells, the venom had the strongest cytotoxicity on H630 cells with the 50% lethal concentration (IC(50)) of 5.1 ?g/ml. However, the IC(50) on Bel-7402 and SMMC-7721 was approximate 17.9 and 24.3 ?g/ml, respectively. The cytotoxicity of the venom was affected by pH, temperature and storage conditions. At the pH 4.5-8.5, the venom displayed obvious cytotoxicity and the percentage of survival was about 50%. When pre-incubated at temperatures over 60°C for as short as 10 min, the percentage of survival sharply improved from 4.6% up to 80%. The venom was stored in a more stable condition at -80°C and in lyophilized state compared to other storage conditions used in this study. Lactate dehydrogenase release assay performed on H630 cells indicated that exposure to the venom could result in damage to the cell membrane. PMID:21949089

Cuiping, Li; Pengcheng, Li; Jinhua, Feng; Rongfeng, Li; Huahua, Yu

2011-09-23

166

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.

Onizuka, Neil

2011-01-01

167

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

2007-01-11

168

THE STRUCTURE AND FUNCTION OF CENTRIOLES AND THEIR SATELLITES IN THE JELLYFISH PHIALIDIUM GREGARIUM  

PubMed Central

Testes of jellyfish Phialidium gregarium were fixed in 2 per cent OsO4 in Veronal-acetate buffer at pH 7.4. Thin sections showed that in young spermatids the spindle fibers of the last maturation division are attached to satellites of the filament-forming centriole. In more mature spermatids this attachment is not observed. During the developmental phase, nine satellites can be observed emanating from the interspaces between the nine tubular triplets of this centriole. A circular region on each of the enlarged distal ends of the satellites attaches them to the cell membrane. The satellites apparently provide a firm anchor for the axial filament. Each of the epithelial cells covering the testis produces a single long flagellum. On the filament-forming centriole often a satellite can be observed to which tubules are attached. These tubules are 180 A in diameter and probably represent remnants of spindle fibers. It is suggested that the distal centriole has the ability to form several satellites or appendages at appropriate times during the cell cycle. These satellites are distinct from the daughter centrioles in that they are supportive structures: in certain phases of cell life, spindle fibers may attach to them, while in other instances the distal centriole and the flagellum it is forming are anchored by them.

Szollosi, Daniel

1964-01-01

169

Phenotypic plasticity in juvenile jellyfish medusae facilitates effective animal-fluid interaction  

PubMed Central

Locomotion and feeding in marine animals are intimately linked to the flow dynamics created by specialized body parts. This interaction is of particular importance during ontogeny, when changes in behaviour and scale challenge the organism with shifts in fluid regimes and altered functionality. Previous studies have indicated that Scyphozoan jellyfish ontogeny accommodates the changes in fluid dynamics associated with increasing body dimensions and velocities during development. However, in addition to scale and behaviour that—to a certain degree—underlie the control of the animal, flow dynamics are also dependent on external factors such as temperature. Here, we show phenotypic plasticity in juvenile Aurelia aurita medusae, where morphogenesis is adapted to altered fluid regimes imposed by changes in ambient temperature. In particular, differential proportional growth was found to compensate for temperature-dependent changes in viscous effects, enabling the animal to use adhering water boundary layers as ‘paddles’—and thus economize tissue—at low temperatures, while switching to tissue-dominated propulsion at higher temperatures where the boundary layer thickness is insufficient to serve for paddling. This effect was predicted by a model of animal–fluid interaction and confirmed empirically by flow-field visualization and assays of propulsion efficiency.

Nawroth, J. C.; Feitl, K. E.; Colin, S. P.; Costello, J. H.; Dabiri, J. O.

2010-01-01

170

Deduced amino acid sequence of a putative sodium channel from the scyphozoan jellyfish Cyanea capillata.  

PubMed Central

Members of the phylum Cnidaria are the lowest extant organisms to possess a nervous system and are the first that are known to contain cells that produce action potentials carried exclusively by Na+ ions. They thus occupy an important position in the evolution of Na+ channels. A cDNA encoding a 198-kDa protein with high sequence identity to known Na+ channels was isolated from the scyphozoan jellyfish Cyanea capillata. The similarity between this and other Na+ channels is greatest in the transmembrane segments and the putative pore region and less so in the cytoplasmic loops that link the four domains of the protein. Phylogenetic analysis of the deduced protein reveals that it is closely related to known Na+ channels, particularly those of squid and Drosophila, and more distantly separated from Ca2+ channels. Scrutiny of the Cyanea channel in regions corresponding to those purported to form the tetrodotoxin receptor and selectivity filter of Na+ channels in higher animals reveals several anomalies that suggest that current models of the location of the tetrodotoxin binding site and Na+ channel selectivity filter are incomplete. Images Fig. 1 Fig. 2 Fig. 3

Anderson, P A; Holman, M A; Greenberg, R M

1993-01-01

171

Subcellular calcium measurements in mammalian cells using jellyfish photoprotein aequorin-based probes.  

PubMed

The jellyfish Aequorea victoria produces a 22-kDa protein named aequorin that has had an important role in the study of calcium (Ca(2+)) signaling. Aequorin reacts with Ca(2+) via oxidation of the prosthetic group, coelenterazine, which results in emission of light. This signal can be detected by using a special luminescence reader (called aequorinometer) or luminescence plate readers. Here we describe the main characteristics of aequorin as a Ca(2+) probe and how to measure Ca(2+) in different intracellular compartments of animal cells (cytosol, different mitochondrial districts, nucleus, endoplasmic reticulum (ER), Golgi apparatus, peroxisomes and subplasma-membrane cytosol), ranging from single-well analyses to high-throughput screening by transfecting animal cells using DNA vectors carrying recombinant aequorin chimeras. The use of aequorin mutants and modified versions of coelenterazione increases the range of calcium concentrations that can be recorded. Cell culture and transfection takes ?3 d. An experiment including signal calibration and the subsequent analyses will take ?1 d. PMID:24113784

Bonora, Massimo; Giorgi, Carlotta; Bononi, Angela; Marchi, Saverio; Patergnani, Simone; Rimessi, Alessandro; Rizzuto, Rosario; Pinton, Paolo

2013-10-10

172

Marine sterols. III--The sterol compositions of oceanic jellyfish. The use of gas chromatographic mass spectrometric techniques to identify unresolved components.  

PubMed

The sterol compositions of three oceanic jellyfish have been determined using gas chromatographic mass spectrometric techniques involving the use of two separate gas chromatographic column systems. The components in overlapping peaks have been identified by comparison of the mass spectra of peaks in the two column systems using subtractive techniques. A mid-water animal, Periphylla periphylla, was found to contain a very complex and unusual sterol profile including rare 5alpha-stanols, whereas two other oceanic jellyfish Pelagia noctiluca and Atolla wyvillei contained similar mixtures of delta5 sterols to those previously isolated from coastal species. PMID:4172

Ballantine, J A; Roberts, J C; Morris, R J

1976-02-01

173

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

174

Mitochondrial Genome of the Freshwater Jellyfish Craspedacusta sowerbyi and Phylogenetics of Medusozoa  

PubMed Central

The 17,922 base pairs (bp) nucleotide sequence of the linear mitochondrial DNA (mtDNA) molecule of the freshwater jellyfish Craspedacusta sowerbyi (Hydrozoa,Trachylina, Limnomedusae) has been determined. This sequence exhibits surprisingly low A+T content (57.1%), containing genes for 13 energy pathway proteins, a small and a large subunit rRNAs, and methionine and tryptophan tRNAs. Mitochondrial ancestral medusozoan gene order (AMGO) was found in the C. sowerbyi, as those found in Cubaia aphrodite (Hydrozoa, Trachylina, Limnomedusae), discomedusan Scyphozoa and Staurozoa. The genes of C. sowerbyi mtDNA are arranged in two clusters with opposite transcriptional polarities, whereby transcription proceeds toward the ends of the DNA molecule. Identical inverted terminal repeats (ITRs) flank the ends of the mitochondrial DNA molecule, a characteristic typical of medusozoans. In addition, two open reading frames (ORFs) of 354 and 1611 bp in length were found downstream of the large subunit rRNA gene, similar to the two ORFs of ORF314 and polB discovered in the linear mtDNA of C. aphrodite, discomedusan Scyphozoa and Staurozoa. Phylogenetic analyses of C. sowerbyi and other cnidarians were carried out based on both nucleotide and inferred amino acid sequences of the 13 mitochondrial energy pathway genes. Our working hypothesis supports the monophyletic Medusozoa being a sister group to Octocorallia (Cnidaria, Anthozoa). Within Medusozoa, the phylogenetic analysis suggests that Staurozoa may be the earliest diverging class and the sister group of all other medusozoans. Cubozoa and coronate Scyphozoa form a clade that is the sister group of Hydrozoa plus discomedusan Scyphozoa. Hydrozoa is the sister group of discomedusan Scyphozoa. Semaeostomeae is a paraphyletic clade with Rhizostomeae, while Limnomedusae (Trachylina) is the sister group of hydroidolinans and may be the earliest diverging lineage among Hydrozoa.

Zou, Hong; Zhang, Jin; Li, Wenxiang; Wu, Shangong; Wang, Guitang

2012-01-01

175

Developmental and evolutionary aspects of the basic helix–loop–helix transcription factors Atonal-like 1 and Achaete-scute homolog 2 in the jellyfish  

Microsoft Academic Search

The close functional link of nerve and muscle cells in neuromuscular units has led to the hypothesis of a common evolutionary origin of both cell types. Jellyfish are well suited to evaluate this theory since they represent the most basal extant organisms featuring both striated muscle and a nervous system. Here we describe the structure and expression of two novel

Katja Seipel; Nathalie Yanze; Volker Schmid

2004-01-01

176

[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

177

The lethality of tentacle-only extract from jellyfish Cyanea capillata is primarily attributed to cardiotoxicity in anaesthetized SD rats  

Microsoft Academic Search

Previous studies in our laboratory have shown that tentacle-only extract (TOE) has similar hypotensive effects with nematocyst venom from jellyfish Cyanea capillata, and the experimental studies on the in vivo cardiovascular effects of TOE were further performed to explore the leading cause of death and analyze the basic physiopathologic change in anaesthztized SD rats. Plots of TOE dose versus time

Liang Xiao; Guan-sheng Liu; Qian-qian Wang; Qian He; Si-hua Liu; Yue Li; Jing Zhang; Li-ming Zhang

2010-01-01

178

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

179

Isolation, identification and characterization of a novel antioxidant protein from the nematocyst of the jellyfish Stomolophus meleagris.  

PubMed

Reactive oxygen species (ROS) can damage the lipids, proteins and DNA when produced excessively in cells. Here, we describe the isolation and identification of a novel antioxidant protein named SmP90 from the nematocyst of jellyfish Stomolophus meleagris by 50% ammonium sulfate precipitation and gel filtration chromatography, superdex75. HPLC and SDS-PAGE analysis revealed >95% purity of SmP90 with apparent molecular weight of 90 kDa, approximately. The identification of SmP90 was confirmed by both N-terminal amino acids sequencing, with the sequences of NLDTPYCFYSGDYGG, and peptide mass fingerprint (PMF) analysis by MALDI-TOF-MS. However, no known protein had been completely matched in the database, which indicated that SmP90 might be a novel protein. The antioxidant assay result showed that it had strong superoxide anion radical-scavenging activity with the half-scavenging concentration (EC(50)) of about 16 ?g/mL. Therefore, the present study is the first time to demonstrate a high efficient method of isolating a novel antioxidant protein from the nematocyst of jellyfish S. meleagris. PMID:22627106

Li, Rongfeng; Yu, Huahua; Xing, Ronge; Liu, Song; Qing, Yukun; Li, Kecheng; Li, Bing; Meng, Xiangtao; Cui, Jinhui; Li, Pengcheng

2012-05-22

180

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

181

Lipid peroxidation is another potential mechanism besides pore-formation underlying hemolysis of tentacle extract from the jellyfish Cyanea capillata.  

PubMed

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

2013-01-09

182

Cardiovascular effect is independent of hemolytic toxicity of tentacle-only extract from the jellyfish Cyanea capillata.  

PubMed

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

Liang, Xiao; Beilei, Wang; Ying, Li; Qianqian, Wang; Sihua, Liu; Yang, Wang; Guoyan, Liu; Jia, Lu; Xuting, Ye; Liming, Zhang

2012-08-15

183

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

184

Interannual variability in the Northern California Current food web structure: Changes in energy flow pathways and the role of forage fish, euphausiids, and jellyfish  

NASA Astrophysics Data System (ADS)

The Northern California Current (NCC) is a seasonally productive and open ecosystem. It is home to both a diverse endemic community and to seasonally transient species. Productivity and food web structure vary seasonally, interannually, and decadally due to variability in coastal upwelling, climate-scale physical processes, and the migratory species entering the system. The composition of the pelagic community varies between years, including changes to mid-trophic level groups that represent alternate energy-transfer pathways between lower and upper trophic levels (forage fishes, euphausiids, jellyfish). Multiple data sets, including annual spring and summer mesoscale surveys of the zooplankton, pelagic fish, and seabird communities, were used to infer NCC trophic network arrangements and develop end-to-end models for each of the 2003-2007 upwelling seasons. Each model was used to quantify the interannual variability in energy-transfer efficiency from bottom to top trophic levels. When each model was driven under an identical nutrient input rate, substantial differences in the energy available to each functional group were evident. Scenario analyses were used to examine the roles of forage fishes, euphausiids, and jellyfish (small gelatinous zooplankton and large carnivorous jellyfish) as alternate energy transfer pathways. Euphausiids were the more important energy transfer pathway; a large proportion of the lower trophic production consumed was transferred to higher trophic levels. In contrast, jellyfish acted as a production loss pathway; little of the production consumed was passed upwards. Analysis of the range of ecosystem states observed interannually and understanding system sensitivity to variability among key trophic groups improves our ability to predict NCC ecosystem response to short- and long-term environmental change.

Ruzicka, James J.; Brodeur, Richard D.; Emmett, Robert L.; Steele, John H.; Zamon, Jeannette E.; Morgan, Cheryl A.; Thomas, Andrew C.; Wainwright, Thomas C.

2012-09-01

185

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

Microsoft Academic Search

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),

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

2011-01-01

186

Haemodynamic effects of the crude venom from nematocysts of the box-jellyfish Chiropsalmus quadrigatus (Habu-kurage) in anaesthetized rabbits  

Microsoft Academic Search

Haemodynamic effects of saline-extracted venom from nematocysts isolated from tentacles of the box-jellyfish Chiropsalmus quadrigatus (Habu-kurage) were investigated. In anaesthetized rabbits, i.v. injections of the venom produced hypotension following a transient hypertension. Mean femoral arterial blood flow markedly decreased immediately after the injection and femoral vascular resistance increased. Left ventricular dP\\/dt remarkably decreased after a transient and small increase, and

Tomoyuki Koyama; Katsuhiko Noguchi; Toshihiro Matsuzaki; Mayuko Sakanashi; Junko Nakasone; Kanako Miyagi; Makiko Sakanashi; Matao Sakanashi

2003-01-01

187

Large-scale sampling reveals the spatio-temporal distributions of the jellyfish Aurelia aurita and Cyanea capillata in the Irish Sea  

Microsoft Academic Search

At-sea distributions of large scyphozoan jellyfish across the Irish Sea were studied using visual surface counts from ships\\u000a of opportunity. Thirty-seven surveys were conducted along two >100 km long transects between Ireland and the UK from April\\u000a to September in 2009 and 2010. Five species were recorded but only Aurelia aurita and Cyanea capillata were frequently observed. The first formal description

Thomas Bastian; Damien Haberlin; Jennifer E. Purcell; Graeme C. Hays; John Davenport; Rob McAllen; Thomas K. Doyle

188

Effects of turbidity on survival of larval ayu and red sea bream exposed to predation by jack mackerel and moon jellyfish  

Microsoft Academic Search

We conducted laboratory experiments to examine the effects of turbidity on the survival of red sea bream Pagrus major and ayu Plecoglossus altivelis altivelis larvae when exposed to either visual (jack mackerel juveniles) or tactile (moon jellyfish) predators. The experiments were\\u000a conducted in 30-l tanks with three different levels of turbidity obtained by dissolving 0, 50, or 300 ppm kaolin. Predators

Ryosuke Ohata; Reiji Masuda; Masahiro Ueno; Yuichi Fukunishi; Yoh Yamashita

2011-01-01

189

Reproductive strategy of the jellyfish Aurelia aurita (Cnidaria Scyphomedusae) in the Suez Canal and its migration between the Red Sea and Mediterranean  

Microsoft Academic Search

The life history of the common jellyfish A. aurita (Linnaeus) in the Suez Canal was investigated by monthly sampling over a 28 month period from September 2006 to December 2008. Young medusae of 2–3 cm diameter appeared during February\\/March. Growth was rapid. Some specimens of this cohort reached 16 cm and spawned by March\\/May and then decreased in size or

Hamed A. El-Serehy; Khaled A. Al-Rasheid

2011-01-01

190

The lethality of tentacle-only extract from jellyfish Cyanea capillata is primarily attributed to cardiotoxicity in anaesthetized SD rats.  

PubMed

Previous studies in our laboratory have shown that tentacle-only extract (TOE) has similar hypotensive effects with nematocyst venom from jellyfish Cyanea capillata, and the experimental studies on the in vivo cardiovascular effects of TOE were further performed to explore the leading cause of death and analyze the basic physiopathologic change in anaesthztized SD rats. Plots of TOE dose versus time to death showed dose-dependent curvilinear relationship. ECG changed in a dose- and time-dependent manner. Haemodynamic parameters, including the heart rate, mean femoral arterial pressure, left ventricular developed pressure and the first derivative of left ventricular pressures, decreased, but left ventricular end-diastolic pressure did not increase. Arterial partial pressure of oxygen and oxygen saturation did not change. Lactate dehydrogenase, creatine kinase and MB isoenzyme of creatine kinase increased significantly. Histopathological examination showed congestion, haemorrhage, edema and denaturation in the heart; congestion, haemorrhage in the lung and acute congestion in the liver. Transmission electron microscopy examination found that parts of sarcomeric filaments disrupted, dissolved and disappeared, and parts of mitochondria swelled in cardiocytes. Laser scanning confocal microscope examination found that ventricular myocytes from adult rat were deformed and ultimately died within 30 min after TOE treatment. Our results reveal that cardiodepressive effect of C. capillata TOE is the leading cause of death and acute total heart failure is the basic physiopathologic change in anaesthetized SD rats. PMID:20025895

Xiao, Liang; Liu, Guan-sheng; Wang, Qian-qian; He, Qian; Liu, Si-hua; Li, Yue; Zhang, Jing; Zhang, Li-ming

2009-12-16

191

Spatial distribution of the upside-down jellyfish Cassiopea sp. within fringing coral reef environments of the Northern Red Sea: implications for its life cycle  

NASA Astrophysics Data System (ADS)

The zooxanthellate mangrove jellyfish Cassiopea sp. represents a prominent invasive species and a potential bioindicator for nutrient monitoring in coral reefs. However, information about its spatial distribution in combination with abundance, habitat specificity and life cycle elements is barely available. This study, therefore, presents the results of field surveys conducted within four different benthic habitat types (coral reef, seagrass meadow, reef-sand transition and sand flat) in the Northern Red Sea. Cassiopea sp. exhibited a highly patchy distribution within the entire study area with mean abundance of 1.6 ± 0.3 animals m-2 and benthic coverage of 3.2%. Within coral reef habitats, maximum abundance of up to 31 animals m-2 and benthic coverage of up to 20% were detected. Additionally, this study revealed that 65% of all observed Cassiopea specimens were associated with the commensalistic crustacean mysid Idiomysis tsurnamali. Cassiopea abundance and size as well as association patterns with mysids differed between most of the surveyed habitats. In summary, the findings of the present study (1) characterize Cassiopea as one of the key organisms in investigated benthic habitats, (2) indicate active habitat selection by the jellyfish and (3) may hint to an unexplored life cycle of Cassiopea with central role of seagrass meadows providing cues for larval settlement and metamorphosis in the absence of mangroves.

Niggl, Wolfgang; Wild, Christian

2010-12-01

192

Skin lesions in envenoming by cnidarians (Portuguese man-of-war and jellyfish): etiology and severity of accidents on the Brazilian coast.  

PubMed

This work attempts to establish dermatological identification patterns for Brazilian cnidarian species and a probable correlation with envenoming severity. In an observational prospective study, one hundred and twenty-eight patients from the North Coast region of São Paulo State, Brazil were seen between 2002 and 2008. About 80% of these showed only local effects (erythema, edema, and pain) with small, less than 20 cm, oval or round skin marks and impressions from small tentacles. Approximately 20% of the victims had long, more than 20 cm, linear and crossed marks with frequent systemic phenomena, such as malaise, vomiting, dyspnea, and tachycardia. The former is compatible with the common hydromedusa from Southeast and Southern Brazil (Olindias sambaquiensis). The long linear marks with intense pain and systemic phenomena are compatible with envenoming by the box jellyfish Tamoya haplonema and Chiropsalmus quadrumanus and the hydrozoan Portuguese man-of-war (Physalis physalis). There was an association between skin marks and probable accident etiology. This simple observation rule can be indicative of severity, as the Cubozoa Class (box jellyfish) and Portuguese man-of-war cause the most severe accidents. In such cases, medical attention, including intensive care, is important, as the systemic manifestations can be associated with death. PMID:20305955

Haddad Junior, Vidal; Silveira, Fábio Lang da; Migotto, Alvaro Esteves

193

Mitochondrial dysfunction contributes to the cytotoxicity induced by tentacle extract from the jellyfish Cyanea capillata in rat renal tubular epithelial NRK-52E cells.  

PubMed

Our previous studies have shown that tentacle extract (TE) from the jellyfish Cyanea capillata could induce a delayed jellyfish envenomation syndrome with severe multiple organ dysfunctions, among which renal injury with tubular necrosis seemed to be most serious. So, in this study, we aimed to explore the toxic effect of TE on rat renal tubular epithelial NRK-52E cells. Based on the previous findings that TE could cause oxidative damage in erythrocytes, the effects of TE on cell oxidative stress conditions, including ROS production and lipid peroxidation, and mitochondrial dysfunction associated with cell death were investigated in NRK-52E cells. The results showed that TE caused cell morphological change and decreased cell viability through induction of apoptosis and necrosis in NRK-52E cells. Meanwhile, ROS overproduction and mitochondrial membrane potential decrease were found before the cell death occurred. It was concluded that TE could induce cytotoxicity, especially apoptosis and necrosis, in NRK-52E cells, and mitochondrial dysfunction and ROS overproduction might play important roles in the process of cell injury and death. PMID:23916600

Wang, Tao; He, Qian; Xiao, Liang; Wang, Qianqian; Zhang, Bo; Wang, Beilei; Liu, Guoyan; Zheng, Jiemin; Yu, Bentong; Zhang, Liming

2013-08-02

194

Effect of low dissolved oxygen concentrations on behavior and predation rates on red sea bream Pagrus major larvae by the jellyfish Aurelia aurita and by juvenile Spanish mackerel Scomberomorus niphonius  

Microsoft Academic Search

A shift in outcomes of predator-prey interactions in plankton community may occur at sublethal dissolved oxygen concentrations that commonly occur in coastal waters. Laboratory experiments were conducted to investigate how a decline in dissolved oxygen concentration alters the predation rate on fish larvae by two estuarine predators. Behavior and consumption of larval fish by moon jellyfish Aurelia aurita (103.1±12.4 mm in

J. Shoji; R. Masuda; Y. Yamashita; M. Tanaka

2005-01-01

195

Snakes, Jellyfish and Spiders  

Microsoft Academic Search

Our knowledge of animal and human physiological processes owes much to over a century of study of natural toxins. The neurotoxins\\u000a of kraits (bungarotoxins from Bungarus spp.) and cobras (Naja spp.) have helped define the acetylcholine receptor and neuromuscular transmission. Axonal trafficking and sodium channels\\u000a have been studied using tetrodotoxin from the blue-ringed octopus (Hapalochlaena spp.) and puffer fish (fugu).

Bart J. Currie

196

Oxidative stress induced by crude venom from the jellyfish Pelagia noctiluca in neuronal-like differentiated SH-SY5Y cells.  

PubMed

Marine toxins are a suitable research model and their mechanism of action is intriguing and still under debate. Either a pore formation mechanism or oxidative stress phenomena may explain the damage induced by toxins. The effect of crude venom from isolated nematocysts of the jellyfish Pelagia noctiluca on neuronal-like cells derived from human neuroblastoma SH-SY5Y has been here studied. To prove the possible oxidative stress events, cell viability, assessed by MTT quantitative colorimetric assay, intracellular reactive oxygen species (ROS) quantified by the non-fluorescent probe H2DCF-DA and changes in mitochondrial transmembrane potential (??m) measured by the incorporation of a cationic fluorescent dye rhodamine-123 were verified on venom-treated cells (0.05-0.5?g/ml doses). A dose- and time-dependent reduction of all parameters was observed after venom treatment. NAC (N-acetyl-cysteine), antioxidant applied before crude venom application, significantly counteracted the decrease in cell viability and ROS production, while ??m was only partially restored. The disruption of mitochondrial membrane by P. noctiluca crude venom may thus induce oxidative stress by inhibiting mitochondrial respiration and uncoupling oxidative phosphorylation, sensitizing mitochondria in SH-SY5H cells and facilitating membrane permeability. In sum, our findings suggest that P. noctiluca crude venom directly induces ??m collapse with further generation of ROS and add novel information to the understanding of such toxins, still not completely clarified. PMID:22445879

Morabito, Rossana; Condello, Salvatore; Currò, Monica; Marino, Angela; Ientile, Riccardo; La Spada, Giuseppina

2012-03-14

197

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

198

Biological Invasions by Marine Jellyfish  

Microsoft Academic Search

Comparatively little research has been conducted on the ecology of invasive organisms in marine ecosystems when balanced against\\u000a their terrestrial counterparts (Carlton and Geller 1993). Perhaps rates of invasions in marine systems are simply lower than\\u000a in other systems, but more likely lack of scrutiny, difficulty with taxonomic resolution, and unusual life-history characters\\u000a of marine organisms cause the vast majority

William M. Graham; Keith M. Bayha

199

For the Classroom: "Plastic" Jellyfish.  

ERIC Educational Resources Information Center

|Describes an activity in which students monitor the plastic waste production in their households, research its effects on freshwater and marine life, and propose ways to lessen the problem. Provides objectives, background information, materials, procedures, extension activities, and an evaluation for students. (Author/RT)|

Current: The Journal of Marine Education, 1989

1989-01-01

200

Comparison of haemolytic activity of tentacle-only extract from jellyfish Cyanea capillata in diluted whole blood and erythrocyte suspension: diluted whole blood is a valid test system for haemolysis study.  

PubMed

In this paper, we utilized two different test systems to compare the haemolysis of tentacle-only extract (TOE) devoid of nematocysts from jellyfish Cyanea capillata, the 1% whole blood and 0.45% erythrocyte suspension approximately with the same erythrocyte concentration from the blood samples of sheep, rabbit, mouse, rat and human, respectively. Without exception, the haemolytic activity of TOE was dose-dependent in both test systems from all the five kinds of blood samples, while it was generally stronger in erythrocyte suspension than that in diluted whole blood at the relatively high concentration of TOE. When various aliquots of plasma were added into the erythrocyte suspension test system, the haemolytic activity of TOE was declined with the plasma quantity increasing, and dropped to about 20% at the presence of two aliquots of plasma. If serum albumin of 0.5 mg/ml, approximately the same albumin content in 1% whole blood, was added into the erythrocyte suspension test system instead, the haemolysis of TOE was similarly inhibited. The effects of GSH, ascorbic acid and protease inhibitor on the haemolytic activity of TOE were detected in the erythrocyte suspension and diluted whole blood simultaneously, and the test results were coincident between the two systems. These results suggested that the inconsistency of TOE haemolysis between the erythrocyte suspension and diluted whole blood is a universal occurrence in the mammals, and blood plasma plays a dose-dependent protective role against haemolysis which may be due to serum albumin. Diluted whole blood is a valid and convenient test system for haemolysis study in vitro. PMID:21474292

Wang, Qianqian; Xiao, Liang; He, Qian; Liu, Sihua; Zhang, Jing; Li, Yue; Zhang, Zhi; Nie, Fei; Guo, Yufeng; Zhang, Liming

2011-04-06

201

Visual tracking of jellyfish in situ  

Microsoft Academic Search

Marine biologists desire an automated system for observing gelatinous zooplankton. This study represents the first attempt at real-time robotic tracking of a gelatinous animal in the open ocean. Challenges stem from uneven lighting, encounters with other marine life and frequent out-of-frame events. Analysis of a large video library of human-controlled jelly tracking supported selection of an appropriate vision algorithm. The

Jason Rife; Stephen M. Rock

2001-01-01

202

Stokesian jellyfish: viscous locomotion of bilayer vesicles  

NASA Astrophysics Data System (ADS)

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 efficiencies are similar to that of other low Reynolds number biological swimmers, and suggest that shape-changing vesicles might provide an alternative to flagella-based synthetic microswimmers.

Evans, Arthur A.; Spagnolie, Saverio E.; Lauga, Eric

203

Towards the acoustic estimation of jellyfish abundance  

Microsoft Academic Search

Acoustic target strengths (TSs) of the 2 most common large medusae, Chrysaora hysoscella and Aequorea aequorea, in the northern Benguela (off Namibia) have previously been estimated (at 18, 38 and 120 kHz) from acoustic data collected in conjunction with trawl samples, using the 'comparison method'. These TS values may have been biased because the method took no account of acoustic

Andrew S. Brierley; David C. Boyer; Bjørn E. Axelsen; Christopher P. Lynam; Conrad A. J. Sparks; Helen J. Boyer; Mark J. Gibbons

2005-01-01

204

Feeding rates of the jellyfish Aurelia aurita on fish larvae  

Microsoft Academic Search

We quantified feeding rates of field caught Aurelia aurita feeding on yolk sac cod (Gadus morhua) larvae in a series of incubation experiments. A short-time (~1 h) functional response experiment with a wide range of prey concentrations (0.5–16 prey l?1, initial concentration) revealed that ingestion rates increased linearly over this range, such that clearance rates were similar between the different prey concentrations. This

Josefin Titelman; Lars Johan Hansson

2006-01-01

205

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

206

Pharmacological action of Australian animal venoms.  

PubMed

1. Australia has some of the most venomous fauna in the world. Although humans are not usually perceived as being predators against these animals they are often envenomated, accidentally or otherwise. This has led to the development of antivenoms against some of the potentially lethal venoms. However, further understanding of the mechanism(s) of action of these and other venoms is important, not only for developing new treatment strategies but also in the search for novel research tools. 2. The present review discusses the pharmacology of some of the components found in venoms and outlines the research undertaken on some of Australia's venomous animals, with the exception of snakes. 3. Biogenic amines, peptides and enzymes are common venom components and produce a wide range of effects in envenomated humans. For example, respiratory failure observed after envenomation by the box jellyfish (Chirnex fleckeri) and Sydney funnel-web spider (Atrax robustus) is most likely due to potent neurotoxins in the venoms. Stonefish (Synanceja trachynis) and platypus (Ornithorhynchus anatinus) venoms, although not considered lethal, cause severe pain. However, the components responsible for these effects have not been isolated. Venom components, as yet unidentified, may be responsible for the cutaneous necrotic lesions that have been reported after some spider bites (e.g. Lampona cylindrata). Other venoms, such as those of the jumper ant (Myrmecia pilosula) and bull ant (M. pyriformis), may produce only mild skin irritation to the majority of humans but a severe anaphylactic response in sensitized victims. 4. While there has been a renewed interest in toxinology, further research is required to fully elucidate the pharmacological action of many of these venoms. PMID:9043799

Hodgson, W C

1997-01-01

207

Jellyfish on the Ceiling and Deer in the Den: The Biology of Interior Decoration  

Microsoft Academic Search

Few homes are without at least one or two representations of living things. The author argues that this penchant for organic decoration is related to what Edward O. Wilson calls biophilia, an innate urge in humans to have contact with other species. As many people now live apart from the natural world, pictures, statues, dried flowers and other reminders of

Maura C. Flannery

2005-01-01

208

Opposite patterns of diurnal activity in the box jellyfish Tripedalia cystophora and Copula sivickisi.  

PubMed

Cubozoan medusae have a stereotypic set of 24 eyes, some of which are structurally similar to vertebrate and cephalopod eyes. Across the approximately 25 described species, this set of eyes varies surprisingly little, suggesting that they are involved in an equally stereotypic set of visual tasks. During the day Tripedalia cystophora is found at the edge of mangrove lagoons where it accumulates close to the surface in sun-lit patches between the prop roots. Copula sivickisi (formerly named Carybdea sivickisi) is associated with coral reefs and has been observed to be active at night. At least superficially, the eyes of the two species are close to identical. We studied the diurnal activity pattern of these two species both in the wild and under controlled conditions in laboratory experiments. Despite the very similar visual systems, we found that they display opposite patterns of diurnal activity. T. cystophora is active exclusively during the day, whereas C. sivickisi is actively swimming at night, when it forages and mates. At night T. cystophora is found on the muddy bottom of the mangrove lagoon. C. sivickisi spends the day attached to structures such as the underside of stones and coral skeletons. This species difference seems to have evolved to optimize foraging, since the patterns of activity follow those of the available prey items in their respective habitats. PMID:22426630

Garm, A; Bielecki, J; Petie, R; Nilsson, D-E

2012-02-01

209

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

210

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

211

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

212

Adaptive behaviours of the jellyfish Aurelia labiata in Roscoe Bay on the west coast of Canada  

Microsoft Academic Search

Four behaviours of mature Aurelia labiata medusae (Scyphozoa) were observed. Touching the manubrium with a soft, hollow, silicone rubber ball or a foam rubber ball caused medusae at a depth of 1 m to swim to the surface. Dense aggregations of medusae did not form within 5 m of rock walls. Medusae did not swim into water with salinity <20 parts per

David J. Albert

2008-01-01

213

Jellyfish and other cnidarian envenomations cause pain by affecting TRPV1 channels  

Microsoft Academic Search

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

Eva Cuypers; Angel Yanagihara; Evert Karlsson; Jan Tytgat

2006-01-01

214

The Jellyfish hunter—Jack Barnes: A pioneer medical toxinologist in Australia  

Microsoft Academic Search

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

John Pearn; Peter Fenner

2006-01-01

215

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.

Cuypers, Eva; Yanagihara, Angel; Karlsson, Evert; Tytgat, Jan

2007-01-01

216

Toxicity of jellyfish and sea-anemone venoms on cultured V79 cells  

Microsoft Academic Search

Cnidarian toxins exert an influence on human activities and public health. The cytotoxicity of crude toxins (nematocyst and surrounding tissue venom) of Aequorea aequorea, Rhizostoma pulmo and Anemonia sulcata was assessed on V79 cells. Rhizostoma pulmo and Anemonia sulcata crude venoms showed remarkable cytotoxicity and killed all treated cells at highest tested concentration within 2 and 3 hr, respectively. Aequorea

A. Carli; S. Bussotti; G. L. Mariottini; L. Robbiano

1996-01-01

217

Occurrence of Type S1A Serine Proteases in Sponge and Jellyfish.  

National Technical Information Service (NTIS)

Although serine proteases are found in all kinds of cellular organisms and many viruses, the classic 'chymotrypsin family' (Group S1A by the 1998 Barrett nomenclature) has an unusual phylogenetic distribution, being especially common in animals, entirely ...

A. Rojas R. F. Doolittle

2003-01-01

218

An Action Potential from the Motor Nerves of the Jellyfish Aurellia aurita Lamarck  

Microsoft Academic Search

So long ago as 1878, E. A. Schäfer demonstrated in Aurellia a network of bipolar and tripolar nerve cells the processes of which run in all directions, frequently coming close together at points which have been interpreted as synapses1,2. Using Holmes's method of silver staining, I have been able to confirm this histological picture; moreover, the fibres are similar to

Adrian Horridge

1953-01-01

219

Reproduction of the giant jellyfish, Nemopilema nomurai (Scyphozoa: Rhizostomeae), in 2006-2008 as peripherally-transported populations  

NASA Astrophysics Data System (ADS)

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 study area. The onset of spermatozoa and egg release occurred in September and October, respectively, and peaked in December and January. Medusae migrated eastward from source areas with the Tsushima Warm Current, where they formed gametes and spawned. Peak position and maximum oocyte diameter increased as the gonads developed according to the size-frequency distribution of oocytes. No fertilized eggs or embryos were found in the gonads. The correlation was analyzed with bell diameter, maximum oocyte diameter, sampling date, surface water temperature and gonad color to estimate which environmental factors and maturation indices were related to the maturation stage of females. Maturation stage correlated well with maximum oocyte diameter, which correlated negatively with surface water temperature. There was no significant correlation between bell diameter and maturation stage. Therefore, bell diameter was inappropriate for determining maturation index. Sex could not be distinguished clearly by gonad color. However, light pink gonads were more prevalent in males and various deep colors such as orange and brown were more frequent in female medusae.

Iguchi, Naoki; Lee, Hye Eun; Yoon, Won Duk; Kim, Suam

2010-06-01

220

The anatomy of the nervous system of the hydrozoan jellyfish, Polyorchis penicillatus, as revealed by a monoclonal antibody.  

PubMed

Dissociated cells from the margin and tentacles of the hydromedusa Polyorchis penicillatus were centrifuged in a Percoll gradient to remove cnidocytes. The resulting formaldehyde-fixed cells were used to inoculate mice to produce monoclonal antibodies. One of the hybridomas, which secreted antibodies against all neurons, was cloned and designated as mAb 5C6. Immunohistochemical labelling with mAb 5C6 of whole-mount preparations and paraffin sections provided a far more complete picture of the organisation of the hydromedusan nervous system than was previously available when using neuronal labelling techniques that restrict labelling to certain neuronal types. Besides confirming anatomical features described in earlier studies these techniques allowed us to discover a number of new structures and to determine connections that were only suspected. Such findings included:1. The discovery of an arch-like connection between the swimming motor neuron network at the apices of the subumbrellar muscle sheets 2. An orthogonal network connecting each pair of radial nerves in each radius 3. Continuity of a central branch of the radial nerve with the radial innervation of the manubrium 4. Details of the sensory neuronal contribution to the microanatomy of the ocelli and cnidocyte batteries 5. Presence of specialised receptor cells in the margin at the bases of tentacles 6. Neurons apparently innervating the radial muscles of the velum 7. Isolated neurons in the peduncle and gonads PMID:12488976

Lin, Y C; Gallin, W J; Spencer, A N

2001-08-15

221

Effects of bleaching and nutrient supplementation on wet weight in the jellyfish Cassiopea xamachana (Bigelow) (Cnidaria: Scyphozoa)  

Microsoft Academic Search

Cassiopea xamachana were bleached by elevated temperature or held in complete darkness. Wet weight was measured over several weeks in bleached and unbleached individuals with or without addition of dissolved organic matter (DOM) and\\/or particulate organic matter (POM) in a three-factor experiment. Wet weight decreased to a greater extent in temperature-bleached individuals compared to unbleached individuals. Bleaching by darkness produced

Cheryl J. McGill; Christopher M. Pomory

2008-01-01

222

Gland cells in the tentacles of the jellyfish Cyanea lamarcki reactive with an antibody against 5-hydroxytryptamine  

Microsoft Academic Search

A lightand electron-microscopic immunocytochemical study on the localization of 5-hydroxytryptamine in Cyanea lamarcki revealed a reaction product in the epidermal gland cells surrounding the nematocyst clusters. The closely related scyphozoan medusa Cyanea capillata lacked a reaction product in the similar mucus-producing gland cells. Earlier conflicting views on the presence and localization of 5-hydroxytryptamine in coelenterates can thus be due to

Rolf Elofsson; Mats Carlberg

1989-01-01

223

The in vivo cardiovascular effects of the Irukandji jellyfish ( Carukia barnesi) nematocyst venom and a tentacle extract in rats  

Microsoft Academic Search

Envenoming by Carukia barnesi may produce life-threatening Irukandji syndrome. There is little published on the activity of C. barnesi venom. This is the first study to investigate the in vivo cardiovascular effects of C. barnesi venom and a tentacle extract (devoid of nematocysts).Venom (50?g\\/kg or 100?g\\/kg, i.v.) produced a pressor response (42±3 and 44±6mmHg, respectively; n=4) and increase in heart

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

2005-01-01

224

Morphological differences between, and reproductive isolation of, two populations of the jellyfish Cyanea in Long Island Sound, USA  

Microsoft Academic Search

Two populations of Cyanea, one in the Niantic River estuary and the other in the adjacent Niantic Bay portion of Long Island Sound, were studied for more than a decade. The estuary and the bay are connected by a narrow channel: this and hydrographic features constrain transport between them. Specimens from each site exhibit morphological and seasonal differences comparable to

Robert H. Brewer

1991-01-01

225

Two-step purification and in vitro characterization of a hemolysin from the venom of jellyfish Cyanea nozakii Kishinouye.  

PubMed

Hemolysin is one of the most hazardous components in the venom of Cyanea nozakii Kishinouye. Here we describe the purification and in vitro characterization of the hemolysin, which we named CnPH. The CnPH was isolated by anion-exchange and size-exclusion chromatography from the nematocyst venom. Two protein bands with molecular masses of 20 kDa, 60 kDa respectively were shown in the reducing SDS-PAGE analysis of the CnPH. And Approximately 5 ?g/mL of the CnPH resulted in 50% hemolysis of the erythrocyte suspension. The hemolytic activity of the CnPH was both temperature and pH dependent. Moreover, it was significantly inhibited in the presence of divalent metal cations, including Cu(2+), Mg(2+), Mn(2+), Zn(2+) and Ca(2+), but enhanced in the presence of EDTA. However, how CnPH performs its hemolytic activity is not yet clear, therefore the mechanism of the hemolytic activity of the CnPH is under research. PMID:21435351

Li, Rongfeng; Yu, Huahua; Feng, Jinhua; Xing, Ronge; Liu, Song; Wang, Lin; Qin, Yukun; Li, Kecheng; Li, Pengcheng

2011-03-22

226

Two-step purification and in vitro characterization of a hemolysin from the venom of jellyfish Cyanea nozakii Kishinouye  

Microsoft Academic Search

Hemolysin is one of the most hazardous components in the venom of Cyanea nozakii Kishinouye. Here we describe the purification and in vitro characterization of the hemolysin, which we named CnPH. The CnPH was isolated by anion-exchange and size-exclusion chromatography from the nematocyst venom. Two protein bands with molecular masses of 20kDa, 60kDa respectively were shown in the reducing SDS–PAGE

Rongfeng Li; Huahua Yu; Jinhua Feng; Ronge Xing; Song Liu; Lin Wang; Yukun Qin; Kecheng Li; Pengcheng Li

2011-01-01

227

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

228

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

229

Marine Bites and Stings  

Microsoft Academic Search

The major box jellyfish is found throughout tropical Australia, with cases being reported from Gladstone (Qld), through to Broome in WA. The greatest numbers of cases occur in the NT. In the NT, major box jellyfish stings have occurred in every month of the year, except one, where as in Qld the jellyfish season is said to be October to

Mark Little; Mike Barnes; Primrose Underhill

230

A toxin homology domain in an astacin-like metalloproteinase of the jellyfish Podocoryne carnea with a dual role in digestion and development  

Microsoft Academic Search

Metalloproteinases of the astacin family such as tolloid play major roles in animal morphogenesis. Cnidarians are thought\\u000a to be evolutionary simple organisms and, therefore, a metalloproteinase from the marine hydrozoan Podocoryne carnea was analysed to evaluate the role of this conserved gene familiy at the base of animal evolution. Surprisingly, the proteinase\\u000a domain of Podocornyne PMP1 is more similar to

T.-L. Pan; Hans Gröger; Volker Schmid; J. Spring

1998-01-01

231

Cardiovascular effects and lethality of venom from nematocysts of the box-jellyfish Chiropsalmus quadrigatus (Habu-kurage) in anaesthetized rats  

Microsoft Academic Search

Haemodynamic effects of saline-extracted venom from nematocysts isolated from Chiropsalmus quadrigatus (Habu-kurage) were studied in anaesthetized rats. Intravenous administration of venom (0.2–5?gprotein\\/kg) produced immediately dose-dependent hypertension and bradycardia. Femoral blood flow transiently increased but calculated femoral vascular conductance decreased. Changes caused by 1?g\\/kg of venom were reproducible, and were not affected by prazosin, atropine or BQ123 (ETA receptor antagonist) but

Katsuhiko Noguchi; Mayuko Sakanashi; Toshihiro Matsuzaki; Junko Nakasone; Makiko Sakanashi; Tomoyuki Koyama; Naobumi Hamadate; Matao Sakanashi

2005-01-01

232

Green-Fluorescent Protein from the Bioluminescent Jellyfish Clytia gregaria Is an Obligate Dimer and Does Not Form a Stable Complex with the Ca2+-Discharged Photoprotein Clytin  

Microsoft Academic Search

Green-fluorescent protein (GFP) is the origin of the green bioluminescence color exhibited by several marine hydrozoans and anthozoans. The mechanism is believed to be Fo?rster resonance energy transfer (FRET) within a luciferase?GFP or photoprotein?GFP complex. As the effect is found in vitro at micromolar concentrations, for FRET to occur this complex must have an affinity in the micromolar range. We

N. P. Malikova; N. V. Visser; Hoek van A; V. V. Skakun; E. S. Vysotski; J. Lee; A. J. W. G. Visser

2011-01-01

233

Dermatitis due to Olindias sambaquiensis: a case report.  

PubMed

Olindias sambaquiensis, Muller 1861 (Hydrozoa: Limnomedusae: Olindiidae) is a neritic jellyfish endemic in the Blanca Bay area (South of Buenos Aires, Argentina). In this paper we describe the first report of a dermatitis caused by this jellyfish in a thirty-four-year-old marine biologist who presented with an erythematous vesicular eruption after contact with Olindias sambaquiensis. Some preliminary ultramicroscopic observations on the nematocysts of this jellyfish are also reported. PMID:8099877

Kokelj, F; Mianzan, H; Avian, M; Burnett, J W

1993-05-01

234

Investigations of combinations of mutations in the jellyfish green fluorescent protein (GFP) that afford brighter fluorescence, and use of a version (VisGreen) in plant, bacterial, and animal cells  

Microsoft Academic Search

Among the GFPs used for imaging green fluorescence, the Emerald version has been considered the best GFP to use but there is no formal report on its construction or the relevance of the amino acid (aa) substitutions in it relative to the commonly used GFPs. Here, we have shown that a version of Emerald makes Escherichia coli host cells visibly

Prapapan Teerawanichpan; Travis Hoffman; Paula Ashe; Raju Datla; Gopalan Selvaraj

2007-01-01

235

DNA sequence organization in the genomes of five marine invertebrates  

Microsoft Academic Search

The arrangement of repetitive and non-repetitive sequence was studied in the genomic DNA of the oyster (Crassostrea virginica), the surf clam (Spisula solidissima), the horseshoe crab (Limulus polyphemus), a nemertean worm (Cerebratulus lacteus) and a jellyfish (Aurelia aurita). Except for the jellyfish these animals belong to the protostomial branch of animal evolution, for which little information regarding DNA sequence organization

Robert B. Goldberg; William R. Crain; Joan V. Ruderman; Gordon P. Moore; Thomas R. Barnett; Ratchford C. Higgins; Robert A. Gelfand; Glenn A. Galau; Roy J. Britten; Eric H. Davidson

1975-01-01

236

Biochemical and molecular characterisation of cubozoan protein toxins  

Microsoft Academic Search

Class Cubozoa includes several species of box jellyfish that are harmful to humans. The venoms of box jellyfish are stored and discharged by nematocysts and contain a variety of bioactive proteins that are cytolytic, cytotoxic, inflammatory or lethal. Although cubozoan venoms generally share similar biological activities, the diverse range and severity of effects caused by different species indicate that their

Diane L. Brinkman; James N. Burnell

2009-01-01

237

Problems with Legs and Feet  

MedlinePLUS

... Sleepaway Camp? Kids Talk About: Summer Vacations Quiz: Baseball Injuries Jellyfish The Pink Locker Society Problems With ... develop a full arch. Very rarely, this requires surgery. Some kids might wear arch supports if their ...

238

What You Need to Know About Drugs: Heroin  

MedlinePLUS

... Sleepaway Camp? Kids Talk About: Summer Vacations Quiz: Baseball Injuries Jellyfish The Pink Locker Society What You ... to treat pain, such as when someone has surgery or breaks a bone, heroin is an illegal ...

239

All about Adenoids  

MedlinePLUS

... Sleepaway Camp? Kids Talk About: Summer Vacations Quiz: Baseball Injuries Jellyfish The Pink Locker Society All About ... This means going into the hospital and having surgery. Sometimes, tonsils and adenoids are removed at the ...

240

Hey! A Flea Bit Me!  

MedlinePLUS

... Injuries Jellyfish The Pink Locker Society Hey! A Flea Bit Me! KidsHealth > Kids > Illnesses & Injuries > Bug Bites ... Do How to Avoid Getting Bitten What's a Flea? A flea is a small (no bigger than ...

241

Hey! A Bedbug Bit Me!  

MedlinePLUS

... Injuries Jellyfish The Pink Locker Society Hey! A Bedbug Bit Me! KidsHealth > Kids > Illnesses & Injuries > Bug Bites ... Do How to Avoid Getting Bitten What a Bedbug Is A bedbug is a small (about the ...

242

50 CFR Table 2d to Part 679 - Species Codes-Non-FMP Species  

Code of Federal Regulations, 2010 CFR

...Grenadier (rattail) 213 Jellyfish (unspecified) 625 Lamprey, Pacific 600 Lingcod 130 Lumpsucker 216 Pacific... 260 Pacific hagfish 212 Pacific hake 112 Pacific lamprey 600 Pacific saury 220 Pacific tomcod 250...

2010-10-01

243

50 CFR Table 2d to Part 679 - Species Codes-Non-FMP Species  

Code of Federal Regulations, 2010 CFR

...Grenadier (rattail) 213 Jellyfish (unspecified) 625 Lamprey, Pacific 600 Lingcod 130 Lumpsucker 216 Pacific... 260 Pacific hagfish 212 Pacific hake 112 Pacific lamprey 600 Pacific saury 220 Pacific tomcod 250...

2009-10-01

244

The Amino Acid Content of Sea Nettle ('Chrysaora quinquecirrha') Nematocysts.  

National Technical Information Service (NTIS)

A study of nematocyst preparations from the jellyfish, Chrysaora quinquecirrha, reveals the presence of hydroxyproline, glycine and other amino acids in concentrations generally compatible with those found in the collagen of invertebrates.

J. H. Stone J. W. Burnett R. Goldner

1969-01-01

245

Properties of the Bioluminescent Protein Aequorin.  

National Technical Information Service (NTIS)

A protein, aequorin from the hydromedusan jellyfish Aequorea having no more than the usual, slight fluorescence of proteins in general, gives a bright, blue, light-emitting reaction with Ca(2+), leading irreversibly to a strongly blue fluorescent protein ...

O. Shimomura F. H. Johnson

1969-01-01

246

76 FR 17107 - Fisheries of the Exclusive Economic Zone Off Alaska; Application for an Exempted Fishing Permit  

Federal Register 2010, 2011, 2012, 2013

...The majority of these other species harvested under the EFP likely would be Pacific cod, skates, flatfish, halibut, and jellyfish. The amount of groundfish harvest under the EFP and by the commercial groundfish fisheries is not expected to exceed...

2011-03-28

247

Introduction to Cnidaria  

NSDL National Science Digital Library

In depth site covers Cnidarian life history, ecology, morphology, systematics, and fossil record. Organisms described include corals, anemones, sea pens, box jellies, siphonophores, hydroids, fire corals, medusae, and true jellyfish. Nice explanations, diagrams, and photos.

248

What's Sweat?  

MedlinePLUS

... Baseball Injuries Jellyfish The Pink Locker Society What's Sweat? KidsHealth > Kids > Q&A > Icky Q & A > What's ... dehydrated (say: dee- hi -drayt-ed). Why Does Sweat Smell? Sweat isn't just wet — it can ...

249

What's West Nile Virus?  

MedlinePLUS

... Baseball Injuries Jellyfish The Pink Locker Society What's West Nile Virus? KidsHealth > Kids > Illnesses & Injuries > Aches, Pains & Injuries > ... are most at risk for the infection. Continue West Nile Symptoms Most of the time, symptoms of West ...

250

36 CFR 7.27 - Dry Tortugas National Park.  

Code of Federal Regulations, 2010 CFR

...Panulirus guttatus ). (10) Marine life means: (i) Sponges, sea anenomes, corals, jellyfish, sea cucumbers, starfish, sea urchins, octopus, crabs, shrimp, barnacles, worms, conch; and (ii) Other animals belonging to the...

2010-07-01

251

Osgood-Schlatter Disease  

MedlinePLUS

... Quiz: Baseball Injuries Jellyfish The Pink Locker Society Osgood-Schlatter Disease KidsHealth > Kids > Illnesses & Injuries > Aches, Pains & Injuries > Osgood-Schlatter Disease Print A A A Text Size Osgood- ...

252

Learning about Carbohydrates  

MedlinePLUS

... Injuries Jellyfish The Pink Locker Society Learning About Carbohydrates KidsHealth > Kids > Staying Healthy > Fabulous Food > Learning About ... of energy for the body. Two Types of Carbohydrates There are two major types of carbohydrates (or ...

253

Finding Out about Fireworks Safety  

MedlinePLUS

... Jellyfish The Pink Locker Society Finding Out About Fireworks Safety KidsHealth > Kids > Staying Safe > Playing It Safe Outdoors and on the Road > Finding Out About Fireworks Safety Print A A A Text Size Isn' ...

254

Letter Responding to Health Claim Petition dated June 23 ...  

Center for Food Safety and Applied Nutrition (CFSAN)

... to, alligator, frog, aquatic turtle, jellyfish, sea cucumber, and sea ... There are only a few studies on this subject ... A case-control study by Guallar et al. ... More results from www.fda.gov/food/ingredientspackaginglabeling/labelingnutrition

255

SEA NETTLE AND MANO'WAR VENOMS: A CHEMICAL COMPARISON OF THEIR VENOMS AND STUDIES ON THE PATHOGENESIS OF THE STING  

Microsoft Academic Search

Sea nettle and Portuguese Man-O'War venoms have many common characteristics and several differences. The mouse lethal factors of both jellyfish have molecular weights of approximately 150,000 and isoelectric points of 4.0–4.5. At least nine lethal fractions can be isolated from each jellyfish by preparative gel electrophoresis. Only sea nettle venom could be easily purified by ammonium sulfate precipitation. The pain

J. W. Burnett; G. J. Calton

1974-01-01

256

Global phylogeography of Cassiopea (Scyphozoa: Rhizostomeae): molecular evidence for cryptic species and multiple invasions of the Hawaiian Islands  

Microsoft Academic Search

The upside-down jellyfish Cassiopea is a globally distributed, semi-sessile, planktonically dispersed scyphomedusa. Cassiopea occurs in shallow, tropical inshore marine waters on sandy mudflats and is generally associated with mangrove-dominated habitats. Controversy over the taxonomy of upside-down jellyfishes precedes their introduction to the Hawaiian Islands during the Second World War, and persists today. Here we address the global phylogeography and molecular

Brenden S. Holland; Michael N. Dawson; Gerald L. Crow; Dietrich K. Hofmann

2004-01-01

257

Effects of pH on asexual reproduction and statolith formation of the scyphozoan, Aurelia labiata  

Microsoft Academic Search

Although anthropogenic influences such as global warming, overfishing, and eutrophication may contribute to jellyfish blooms,\\u000a little is known about the effects of ocean acidification on jellyfish. Most medusae form statoliths of calcium sulfate hemihydrate\\u000a that are components of their balance organs (statocysts). This study was designed to test the effects of pH (7.9, within the\\u000a average current range, 7.5, expected

Amanda K. WinansJennifer; Jennifer E. Purcell

2010-01-01

258

Degradation of the Adriatic medusa Aurelia sp. by ambient bacteria  

Microsoft Academic Search

The decomposition of jellyfish after major bloom events results in the release of large amounts of nutrients, which can significantly\\u000a alter nutrient and oxygen dynamics in the surrounding environment. The response of the ambient bacterial community to decomposing\\u000a jellyfish biomass was evaluated in two marine ecosystems, the Gulf of Trieste (northern Adriatic Sea) and Big Lake (Mljet\\u000a Island, southern Adriatic

Tinkara Tinta; Alenka Malej; Maja Kos; Valentina Turk

2010-01-01

259

Collagen scaffolds derived from a marine source and their biocompatibility  

Microsoft Academic Search

The primary sources of industrial collagens are calf skin and bone. However, these carry a high risk of bovine spongiform encephalopathy or transmissible spongiform encephalopathy. In this study, a novel form of acid-soluble collagen was extracted from jellyfish in an effort to obtain an alternative and safer collagen. Porous scaffolds composed of jellyfish collagen were prepared by freeze-drying and cross-linking

Eun Song; So Yeon Kim; Taehoon Chun; Hyun-Jung Byun; Young Moo Lee

2006-01-01

260

The mauve stinger Pelagia noctiluca (Forsskål, 1775). Distribution, ecology, toxicity and epidemiology of stings. A review.  

PubMed

The toxicity of Cnidaria is a subject of concern due to its influence on humans. In particular, jellyfish blooms can highly affect human economical activities, such as bathing, fishery, tourism, etc., as well as the public health. Stinging structures of Cnidaria (nematocysts) produce remarkable effects on human skin, such as erythema, swelling, burning and vesicles, and at times further severe dermonecrotic, cardio- and neurotoxic effects, which are particularly dangerous in sensitive subjects. In several zones the toxicity of jellyfish is a very important health problem, thus it has stimulated the research on these organisms; to date toxicological research on Cnidarian venoms in the Mediterranean region is not well developed due to the weak poisonousness of venoms of jellyfish and anemones living in this area. In spite of this, during last decades several problems were also caused in the Mediterranean by stinging consequent to Cnidarian blooms mainly caused by Pelagia noctiluca (Forsskål, 1775) which is known to be the most venomous Mediterranean jellyfish. This paper reviews the knowledge on this jellyfish species, particularly considering its occurrence and toxicity. PMID:19005582

Mariottini, Gian Luigi; Giacco, Elisabetta; Pane, Luigi

2008-09-04

261

A hybrid Pseudo-spectral Immersed-Boundary Method for Applications to Aquatic Locomotion  

NASA Astrophysics Data System (ADS)

A hybrid pseudo-spectral immersed boundary method is developed for application in marine locomotion. Spatial derivatives are calculated using pseudo-spectral method while a 2nd-order Runge-Kutta scheme is used for time integration. The singular force applied on the immersed boundary is obtained using a direct forcing method. To avoid Gibb's phenomenon in the spectral method, we regularize the force by smoothing it over several grid cells. This method has the advantage of spectral accuracy and the flexibility to model irregular, moving boundaries on a Cartesian coordinate without complex mesh generation. The method is applied to examine locomotion of jellyfish for both jetting and paddling jellyfish.

Ren, Zheng; Hall, David; Mohseni, Kamran

2011-11-01

262

Investigating the origins of triploblasty: `mesodermal' gene expression in a diploblastic animal, the sea anemone Nematostella vectensis (phylum, Cnidaria; class, Anthozoa)  

Microsoft Academic Search

Mesoderm played a crucial role in the radiation of the triploblastic Bilateria, permitting the evolution of larger and more complex body plans than in the diploblastic, non- bilaterian animals. The sea anemone Nematostella is a non- bilaterian animal, a member of the phylum Cnidaria. The phylum Cnidaria (sea anemones, corals, hydras and jellyfish) is the likely sister group of the

Mark Q. Martindale; Kevin Pang; John R. Finnerty

2004-01-01

263

Genetically modified plants for law enforcement applications  

Microsoft Academic Search

Plants are ubiquitous in the environment and have the unique ability to respond to their environment physiologically and through altered gene expression profiles (they cannot walk away). In addition, plant genetic transformation techniques and genomic information in plants are becoming increasingly advanced. We have been performing research to express the jellyfish green fluorescent protein (GFP) in plants. GFP emits green

C. Neal Stewart

2002-01-01

264

Genetically modified plants for tactical systems applications  

Microsoft Academic Search

Plants are ubiquitous in the environment and have the ability to respond to their environment physiologically and through altered gene expression profiles (they cannot walk away). In addition, plant genetic transformation techniques and genomic information in plants are becoming increasingly advanced. We have been performing research to express the jellyfish green fluorescent protein (GFP) in plants. GFP emits green light

C. Neal Stewart Jr.

2002-01-01

265

A study of the possibility of sprites in the atmospheres of other planets  

Microsoft Academic Search

Sprites are a spectacular type of transient luminous events which occur above thunderstorms immediately after lightning. They have shapes of giant jellyfish, carrots, or columns and last tens of milliseconds. In Earth's atmosphere, sprites mostly emit in red and blue wavelengths from excited N2 and N2+ and span a vertical range between 50 and 90 km above the surface. The

Yoav Yair; Yukihiro Takahashi; Roy Yaniv; Ute Ebert; Yukihiro Goto

2009-01-01

266

Using yeast to shed light on DNA damaging toxins and irradiation.  

PubMed

This unlikely tale of research and development takes us from a Pacific jellyfish to fluorescent green yeast in space, via the high tech world of pharmaceutical screening and an encounter with the YETI. It charts the history of academic research project that through multidisciplinary collaboration and innovation has led to a commercial venture with applications in a number of diverse fields. PMID:15517703

Knight, Andrew W

2004-10-01

267

The properties of mnemiopsin, a bioluminescent and light sensitive protein purified by hollow fiber techniques  

Microsoft Academic Search

A calcium activated photoprotein, termed mnemiopsin, which emits bioluminescence upon the addition of calcium ion, has been isolated from the Ctenophore, Mnemiopsis leidyi, and purified by hollow fiber techniques. The system is similar to aequorin, from the jellyfish Aequorea, except that mnemiopsin can be light-inactivated. Separation of mnemiopsin from the dilute and large volume animal homogenate proved difficult with conventional

S. J. Girsch; J. W. Hastings

1978-01-01

268

Extraction of Renilla-Type Luciferin from the Calcium-Activated Photoproteins Aequorin, Mnemiopsin, and Berovin  

Microsoft Academic Search

Photoproteins, which emit light in an oxygen-independent intramolecular reaction initiated by calcium ions, have been isolated from several bioluminescent organisms, including the hydrozoan jellyfish Aequorea and the ctenophore Mnemiopsis. The system of a related anthozoan coelenterate, the sea pansy Renilla reniformis, however, is oxygen dependent, requiring two organic components, luciferin and luciferase. Previously published indirect evidence indicates that photoproteins may

William W. Ward; Milton J. Cormier

1975-01-01

269

Proteins that glow in green and blue.  

PubMed

An intrinsically fluorescent protein from a Pacific jellyfish promises to become an important power tool in experimental biology. Mutant forms of this green fluorescent protein with altered spectral characteristics have recently been constructed. It is now possible to envision a range of derivatives optimized for specific applications. PMID:9383412

Coxon, A; Bestor, T H

1995-03-01

270

Mnemiopsis leidyi : Distribution and Effect on the Black Sea Ecosystem During the First Years of Invasion in Comparison with Other Gelatinous Blooms  

Microsoft Academic Search

We review the possible sources and effects of the outburst of Mnemiopsis in the Black Sea in comparison with other gelatinous blooms in the Black and Baltic Seas, and in comparison with the dramatic increase of jellyfish biomass (Chrysaora melanaster) in a quite different ecosystem, the arctic Bering Sea, starting in the same period (the early 1990s). Similar patterns were

Ulrich Niermann

271

A bio-inspired shape memory alloy composite (BISMAC) actuator  

Microsoft Academic Search

A beam-shape composite actuator using shape memory alloy (SMA) wires as the active component, termed a Bio-Inspired Shape Memory Alloy Composite (BISMAC), was designed to provide a large deformation profile. The BISMAC design was inspired by contraction of a jellyfish bell, utilizing the rowing mechanism for locomotion. Characterization of maximum deformation in underwater conditions was performed for different actuator configurations

A. A. Villanueva; K. B. Joshi; J. B. Blottman; S. Priya

2010-01-01

272

The Use of GFP to Localize Rho GTPases in Living Cells  

Microsoft Academic Search

The green fluorescent protein (GFP) of the jellyfish Aequorea victoria has revolutionized the study of protein localization and dynamics. GFP fusions permit analysis of proteins in living cells and offer distinct advantages over conventional immunofluorescence. Among these are lower background, higher resolution, robust dual color colocalization, and avoidance of fixation artifacts. In the case of Ras and Rho family proteins,

David Michaelson; Mark Philips

2006-01-01

273

How Does Fluoride Work?  

MedlinePLUS

... Jellyfish The Pink Locker Society How Does Fluoride Work? KidsHealth > Kids > Q&A > Q & A > How Does Fluoride Work? Print A A A Text Size There's fluoride ... even in your water. But how does it work to keep teeth healthy? Let's find out. Fluoride ...

274

Sea Anemone Genome Reveals Ancestral Eumetazoan Gene Repertoire and Genomic Organization  

Microsoft Academic Search

Sea anemones are seemingly primitive animals that, along with corals, jellyfish, and hydras, constitute the oldest eumetazoan phylum, the Cnidaria. Here, we report a comparative analysis of the draft genome of an emerging cnidarian model, the starlet sea anemone Nematostella vectensis. The sea anemone genome is complex, with a gene repertoire, exon-intron structure, and large-scale gene linkage more similar to

Nicholas H. Putnam; Mansi Srivastava; Uffe Hellsten; Bill Dirks; Jarrod Chapman; Asaf Salamov; Astrid Terry; Harris Shapiro; Erika Lindquist; Vladimir V. Kapitonov; Jerzy Jurka; Grigory Genikhovich; Igor V. Grigoriev; Susan M. Lucas; Robert E. Steele; John R. Finnerty; Ulrich Technau; Mark Q. Martindale; Daniel S. Rokhsar

2007-01-01

275

Leatherback turtles: The menace of plastic  

Microsoft Academic Search

The leatherback, Dermochelyscoriacea, is a large sea turtle that feeds primarily on jellyfish. Floating plastic garbage could be mistaken for such prey. Autopsy records of 408 leatherback turtles, spanning 123 years (1885–2007), were studied for the presence or absence of plastic in the GI tract. Plastic was reported in 34% of these cases. If only cases from our first report

N. Mrosovsky; Geraldine D. Ryan; Michael C. James

2009-01-01

276

Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (80th, Chicago, Illinois, July 30-August 2, 1997): Law.  

ERIC Educational Resources Information Center

The Law section of the Proceedings contains the following 10 papers: "Protection without a Shield: Revisiting the Journalist's Common Law Privilege" (Laurence B. Alexander); "Burning the Global Village: The Constitutionality of State Laws Regulating Indecency in Cyberspace" (Dolores L. Flamiano); "Of Jellyfish and Community Leaders: Redefining the…

Association for Education in Journalism and Mass Communication.

277

A Nuclear GFP That Marks Nuclei in Living Drosophila Embryos; Maternal Supply Overcomes a Delay in the Appearance of Zygotic Fluorescence  

Microsoft Academic Search

The central role of gene expression in regulating development has largely been studied by in situ hybridization and antibody staining techniques in fixed material. However, rapid temporal and spatial changes in gene expression are often difficult to correlate with complex morphogenetic movements. A green fluorescent protein (GFP) from the jellyfish, Aequorea victoria, can be used as a real-time reporter for

Ilan Davis; Charles H. Girdham; Patrick H. O'Farrell

1995-01-01

278

Hands-on Science. How Do Sea Critters Make Their Moves?  

ERIC Educational Resources Information Center

Three science experiments teach elementary school students about marine-life locomotion. One teaches primary students how octopi and jellyfish move, using balloons and umbrellas. Another teaches K-6 students the up and down movement of fish in water, using condiment packets. A third teaches 4-6 students about the effect of fish swim bladders,…

VanCleave, Janice

1998-01-01

279

COMPARISON OF PREDICTIVE MODELS FOR GROWTH OF PARENT AND GREEN FLUORESCENT PROTEIN PRODUCING STRAINS OF SALMONELLA  

Technology Transfer Automated Retrieval System (TEKTRAN)

The green fluorescent protein (GFP) from the jellyfish Aequorea victoria can be expressed in and used to follow the fate of Salmonella in microbiologically complex ecosystems, such as food. As a first step in evaluating GFP as a tool for the development of predictive models for naturally contaminat...

280

Learning about Marine Biology. Superific Science Book VI. A Good Apple Science Activity Book for Grades 5-8+.  

ERIC Educational Resources Information Center

Based on the assumption that most students have a natural curiosity about the plant and animal life residing in the oceans, this document provides students in grades five through eight with activities in marine biology. The book provides illustrated information and learning activities dealing with: (1) diatoms; (2) the life cycle of the jellyfish;…

Conway, Lorraine

281

The Science of Museums: Tapping the Social Sciences to Make Exhibits Fathomable and Fun.  

ERIC Educational Resources Information Center

The most successful science-and-technology center exhibits owe as much to the evaluation of visitor reactions as they do to budgets and planning. Explores different types of visitor-evaluation studies and shares examples of successful exhibit designs built upon visitor evaluations, including children's physics exhibits and jellyfish as living art.…

Raloff, Janet

1998-01-01

282

A Sea Creature Treasury. Project CAPE Teaching Module K-2b.  

ERIC Educational Resources Information Center

Fifteen interdisciplinary lessons on marine invertebrates (mollusks, echinoderms, and jellyfish) are provided in this unit designed for students in kindergarten and in grades 1 and 2. Each lesson includes lesson concept, competency goals, objectives, materials needed, background information, teacher preparation, and activities suitable for use in…

Gray, Carmen P.; Forrest, Diane W.

283

TRANSFORMATION OF ESCHERICHIA COLI K-12 WITH A HIGH COPY PLASMID ENCODING THE GREEN FLUORESCENT PROTEIN OF AEQUOREA VICTORIA RESULTS IN REDUCED FITNESS IN THE FORM OF SLOWER GROWTH  

Technology Transfer Automated Retrieval System (TEKTRAN)

The green fluorescent protein (GFP) of the jellyfish Aequorea victoria has been widely used as a biomarker in eucaryotic and prokaryotic cells and has potential for developing predictive models for behavior of single strains of bacteria in naturally contaminated food and environmental samples. Howe...

284

Some Representative Invertebrates from the Cretaceous Period  

NSDL National Science Digital Library

This site provides large, high resolution photos and information about a variety of Cretaceous invertebrate fossil specimens. Fossils are arranged taxonomically and can be viewed by clicking on the appropriate fossil group. Types of organisms covered on the site include Annelids, Jellyfish, Corals, Brachiopods, Echinoids, Gastropods, Crustaceans, Belemnites, Ammonites, and Nautiloids.

Keith, Minor

285

Nature's guiding light  

NASA Astrophysics Data System (ADS)

The Nobel Prize in Chemistry has been awarded for research inspired by jellyfish. This is a reminder that the natural world continues to hint at solutions to modern technological dilemmas, and that when it comes to simple and effective solutions, nature is usually well ahead of man.

2008-11-01

286

Effects of a flexible margin on Robojelly vortex structures  

NASA Astrophysics Data System (ADS)

An Unmanned Underwater Vehicle (UUV) inspired by jellyfish morphology and propulsion mechanism, termed ``Robojelly,'' was used to analyze the effects of the flexible margin on jellyfish propulsion. The natural animal has a bell section which deforms at a different phase then the rest of the bell. This lagging section, referred to as flexible margin or flap, is delimited by the bell margin and an inflexion point. The flap was replicated on the robotic vehicle by a flexible passive material to conduct a systematic parametric study. In a preliminary experiment, Robojelly was tested without a flap and with a flap. This revealed a thrust increase over an order of magnitude. We hypothesize that the length of this passive flap affects the vortex ring circulation strength of the jellyfish which can lead to higher efficiency and thrust. Velocity field measurements were performed using planar Time Resolved Digital Particle Image Velocimetry (TRDPIV) to analyze the change in vortex structures as a function of flap length. The robot input parameters stayed constant over the different configurations tested thus maintaining a near constant power consumption. Results clearly demonstrate that the flap plays an important role in the propulsion mechanism of Robojelly and provides an anatomical understanding of natural jellyfish.

Villanueva, Alex; Stewart, Kelley; Vlachos, Pavlos; Priya, Shashank

2011-11-01

287

Seasonal and vertical distributional patterns of siphonophores and medusae in the Chiloé Interior Sea, Chile  

NASA Astrophysics Data System (ADS)

The horizontal and vertical distribution of jellyfish was assessed in the Chiloé Inland sea, in the northern area of the Chilean Patagonia. A total of 41 species of cnidarians (8 siphonophores, 31 hydromedusae, 2 scyphomedusae) were collected. Eleven jellyfish species were recorded for the first time in the area. Species richness was higher in spring than in winter (37 vs. 25 species, respectively). Species such as Muggiaea atlantica, Solmundella bitentaculata, and Clytia simplex were extremely abundant in spring. The total abundance (408,157 ind 1000 m -3) was 18 times higher in spring than in winter (22,406 ind 1000 m -3). The horizontal distribution of the most abundant species (four in winter, five in spring) showed decreasing abundances in the north-south direction in winter and spring. Peak abundances occurred in the northern microbasins (Reloncaví Fjord, Reloncaví and Ancud gulfs), where the water column stability, phytoplankton and zooplankton abundance were higher, compared with the southern microbasins (Corcovado Gulf, Boca del Guafo). During the spring higher jellyfish abundance season, the vertical distribution of the dominant species (except M. atlantica) showed peak values at mid-depth (30-50 m) and in the deepest sampled layer (50-200 m). This vertical distribution pattern reduced seaward transport in the shallowest layer through estuarine circulation and also limited mortality by predation in the more illuminated shallow layers. Thus, jellyfish were able to remain in the interior waters during the season of maximum biological production.

Palma, Sergio; Silva, Nelson; Cristina Retamal, María; Castro, Leonardo

2011-03-01

288

43 CFR Appendix A to Subpart A of... - Appendix A to Subpart A of Part 17  

Code of Federal Regulations, 2010 CFR

...79 Stat. 1125, 16 U.S.C. 757aâ757f). 6. Aid to Education (70 Stat. 1126, 16 U.S.C. 760d). 7. Jellyfish Act of 1966 (80 Stat. 1149, 16 U.S.C. 1201-1205). (b) Sale, lease, grant, or other disposition of,...

2010-10-01

289

`Green mice' as a source of ubiquitous green cells  

Microsoft Academic Search

The green fluorescent protein (GFP) is responsible for the green bioluminescence of the jellyfish Aequorea victoria. Many classes of GFP mutants exist that display modified fluorescence spectra and an increased extinction coefficient. We produced transgenic mouse lines with an `enhanced' GFP (EGFP) cDNA under the control of a chicken beta-actin promoter and cytomegalovirus enhancer. All of the tissues from these

Masaru Okabe; Masahito Ikawa; Katsuya Kominami; Tomoko Nakanishi; Yoshitake Nishimune

1997-01-01

290

Coelenterate venom research 1991–1995: Clinical, chemical and immunological aspects  

Microsoft Academic Search

Important clinical, chemical, and immunological advances in coelenterate venom research have been made in recent years. Perhaps the most dramatic advance has been in the communication of research data and clinical cases between investigators in this field. Results have been processed by the International Consortium for Jellyfish Stings through their newsletter and the forthcoming publication of the Marine Stinger Book

Joseph W. Burnett; David A. Bloom; Shinichi Imafuku; Heather Houck; Stephen Vanucci; Laure Aurelian; Samuel C. Morris

1996-01-01

291

Toxicity and mAChRs binding activity of Cassiopea xamachana venom from Puerto Rican coasts  

Microsoft Academic Search

A separation of toxic components from the upside down jellyfish Cassiopea xamachana (Cx) was carried out to study their cytotoxic effects and examine whether these effects are combined with a binding activity to cell membrane receptors. Nematocysts containing toxins were isolated from the autolysed tentacles, ruptured by sonication, and the crude venom (CxTX) was separated from the pellets by ultracentrifugation.

Faisal F. Y. Radwan; Laura G. Román; Krishna Baksi; Joseph W. Burnett

2005-01-01

292

managing injuries by venomous sea creatures in Australia  

Microsoft Academic Search

Summary marine injuries or stings are common, but the majority cause only minor effects and do not require medical intervention. Injuries from venomous marine creatures can be divided into jellyfish stings due to contact with nematocysts, and penetrating injuries from spiny fish, stingrays

Geoffrey K Isbister

293

Venomous bites and stings  

Microsoft Academic Search

Bites and stings are common in many tropical countries. Snakebite predominantly affects the rural poor and causes both morbidity and mortality. The clinical features of snake envenoming depend upon the species: both local and systemic envenoming can occur. Spider bites and scorpion, fish and jellyfish stings can all cause significant morbidity, and occasional mortality.

David Lalloo

2010-01-01

294

THE GREEN FLUORESCENT PROTEIN  

Microsoft Academic Search

In just three years, the green fluorescent protein (GFP) from the jellyfish Aequorea victoria has vaulted from obscurity to become one of the most widely studied and exploited proteins in biochemistry and cell biology. Its amazing ability to generate a highly visible, efficiently emitting internal fluorophore is both intrin- sically fascinating and tremendously valuable. High-resolution crystal structures of GFP offer

Roger Y. Tsien

1998-01-01

295

A variant of yellow fluorescent protein with fast and efficient maturation for cell-biological applications  

Microsoft Academic Search

The green fluorescent protein (GFP) from the jellyfish Aequorea victoria has provided a myriad of applications for biological systems. Over the last several years, mutagenesis studies have improved folding properties of GFP (refs 1,2). However, slow maturation is still a big obstacle to the use of GFP variants for visualization. These problems are exacerbated when GFP variants are expressed at

Takeharu Nagai; Keiji Ibata; Eun Sun Park; Mie Kubota; Katsuhiko Mikoshiba; Atsushi Miyawaki

2002-01-01

296

Understanding, improving and using green fluorescent proteins  

Microsoft Academic Search

Green fluorescent proteins (GFPs) are presently attracting tremendous interest as the first general method to create strong visible fluorescence by purely molecular biological means. So far, they have been used as reporters of gene expression, tracers of cell lineage, and as fusion tags to monitor protein localization within living cells. However, the GFP originally cloned from the jellyfish Aequorea victoria

Andrew B. Cubitt; Roger Heim; Stephen R. Adams; Aileen E. Boyd; Larry A. Gross; Roger Y. Tsien

1995-01-01

297

Removal of a Cryptic Intron and Subcellular Localization of Green Fluorescent Protein are Required to Mark Transgenic Arabidopsis Plants Brightly  

Microsoft Academic Search

The green fluorescent protein (GFP) from the jellyfish Aequorea victoria is finding wide use as a genetic marker that can be directly visualized in the living cells of many heterologous organisms. We have sought to express GFP in the model plant Arabidopsis thaliana, but have found that proper expression of GFP is curtailed due to aberrant mRNA processing. An 84-nt

Jim Haseloff; Kirby R. Siemering; Douglas C. Prasher; Sarah Hodge

1997-01-01

298

Breathtaking Discoveries: How Basic Research Led to Treatments for Asthma  

NSDL National Science Digital Library

FASEB Breakthroughs in Bioscience article. A number of animal models have played an invaluable part in key discoveries related to asthma. Experiments involving species as diverse as jellyfish, guinea pigs, and dogs have all shed light on the allergic response that is now known to play a role in asthma.

Margie Patlak (Federation of American Societies for Experimental Biology Office of Public Affairs)

2010-07-12

299

Why Does Eating Ice Cream Give Me a Headache?  

MedlinePLUS

... Quiz: Baseball Injuries Jellyfish The Pink Locker Society Ice Cream Headaches KidsHealth > Kids > Q&A > Q & A > Ice Cream Headaches Print A A A Text Size ... a bad headache . But don't blame the ice cream — it's not acting alone. The roof of ...

300

Chimeric green fluorescent protein as a tool for visualizing subcellular organelles in living cells  

Microsoft Academic Search

Background: It has recently been demonstrated that the green fluorescent protein (GFP) of the jellyfish Aequorea victoria retains its fluorescent properties when recombinantly expressed in both prokaryotic (Escherichia coli) and eukaryotic (Caenorhabditis elegans and Drosophila melanogaster) living cells; it can therefore be used as a powerful marker of gene expression in vivo. The specific targeting of recombinant GFP within cells

Rosario Rizzuto; Marisa Brini; Paola Pizzo; Marta Murgia; Tullio Pozzan

1995-01-01

301

Seascapes: Glimpses of Our Water World.  

ERIC Educational Resources Information Center

|Presented is a collection of newspaper articles prepared by the Delaware Sea Grant Marine Advisory Service during the summer of 1978. Subjects addressed are bioluminescence, beachcomber finds, gulls, beach erosion, marine research activities, barnacles, sand, seaweed, jellyfish, shore restaurants, diving mammals, and tides. (Author/BW)|

Hardin, Jan

302

Trophic Structure and Community Stability in an Overfished Ecosystem  

Microsoft Academic Search

Since the collapse of the pelagic fisheries off southwest Africa in the late 1960s, jellyfish biomass has increased and the structure of the Benguelan fish community has shifted, making the bearded goby (Sufflogobius bibarbatus) the new predominant prey species. Despite increased predation pressure and a harsh environment, the gobies are thriving. Here we show that physiological adaptations and antipredator and

Anne C. Utne-Palm; Anne G. V. Salvanes; Bronwen Currie; Stein Kaartvedt; Göran E. Nilsson; Victoria A. Braithwaite; Jonathan A. W. Stecyk; Matthias Hundt; Megan van der Bank; Bradley Flynn; Guro K. Sandvik; Thor A. Klevjer; Andrew K. Sweetman; Volker Brüchert; Karin Pittman; Kathleen R. Peard; Ida G. Lunde; Rønnaug A. U. Strandabø; Mark J. Gibbons

2010-01-01

303

Directed evolution of a monomeric, bright and photostable version of Clavularia cyan fluorescent protein: structural characterization and applications in fluorescence imaging  

Microsoft Academic Search

The arsenal of engineered variants of the GFP [green FP (fluorescent protein)] from Aequorea jellyfish provides researchers with a powerful set of tools for use in biochemical and cell biology research. The recent discovery of diverse FPs in Anthozoa coral species has provided protein engineers with an abundance of alternative progenitor FPs from which improved variants that complement or supersede

Hui-wang Al

2008-01-01

304

The molecular properties and applications of Anthozoa fluorescent proteins and chromoproteins  

Microsoft Academic Search

The green fluorescent protein (GFP) from the jellyfish Aequorea victoria and its fluorescent homologs from Anthozoa corals have become invaluable tools for in vivo imaging of cells and tissues. Despite spectral and chromophore diversity, about 100 cloned members of the GFP-like protein family possess common structural, biochemical and photophysical features. Anthozoa GFP-like proteins are available in colors and properties unlike

Konstantin A Lukyanov; Vladislav V Verkhusha

2004-01-01

305

Plastic Pollution in the Marine Environment: Boaters Can Help Control a Growing Problem,  

National Technical Information Service (NTIS)

Plastic pollution is a growing problem in the oceans; a problem with dire consequences. A six-pack ring can become a deadly noose for a bird or fish. A plastic bag looks like a tasty jellyfish to an indiscriminate feeder like the sea turtle, but plastic i...

J. G. Farrell

1988-01-01

306

Handle with Care! Mid-Atlantic Marine Animals That Demand Your Respect. Educational Series No. 26. Third Printing.  

ERIC Educational Resources Information Center

|Generally speaking, marine organisms found along middle Atlantic shores are not considered threatening to people. However, some of these animals can cause problems, either upon simple contact with the skin, as in the case of some jellyfish, or through careless handling. In addition, larger inhabitants of coastal waters (such as sharks) must…

Lucy, Jon

307

Evidence of a planktonic food web response to changes in nutrient input dynamics in the Mar Menor coastal lagoon, Spain  

Microsoft Academic Search

Nutrient input dynamics in the Mar Menor coastal lagoon has recently changed as a consequence of changes in agricultural practises. An interannual comparison of the environmental variables and the planktonic biomass size-spectra was performed between 1988 and 1997. While nitrate concentration was low in 1988, the values in 1997 increased considerably. Since 1995, two alloctonous jellyfish species (Rhyzostoma pulmo and

A. Pérez-Ruzafa; J. Gilabert; J. M. Gutiérrez; A. I. Fernández; C. Marcos; S. Sabah

2002-01-01

308

A Sea Creature Treasury. Project CAPE Teaching Module K-2b.  

ERIC Educational Resources Information Center

|Fifteen interdisciplinary lessons on marine invertebrates (mollusks, echinoderms, and jellyfish) are provided in this unit designed for students in kindergarten and in grades 1 and 2. Each lesson includes lesson concept, competency goals, objectives, materials needed, background information, teacher preparation, and activities suitable for use in…

Gray, Carmen P.; Forrest, Diane W.

309

Multiphoton molecular spectroscopy and excited-state dynamics of enhanced green fluorescent protein (EGFP): acid–base specificity  

Microsoft Academic Search

Green fluorescent protein (GFP), isolated from Aequorea victoria jellyfish, has been used extensively as a noninvasive intracellular pH indicator and site-specific fluorescent marker in biochemistry, cell biology, and molecular genetics. Numerous mutations, aimed at optimizing spectroscopic and thermodynamic properties of GFP, have been created for different applications. Fluorescence correlation spectroscopy (FCS) reveals that the enhanced green fluorescent protein mutant (EGFP;

Ahmed A Heikal; Samuel T Hess; Watt W Webb

2001-01-01

310

Red Fluorescent Protein-Aequorin Fusions as Improved Bioluminescent Ca2+ Reporters in Single Cells and Mice  

Microsoft Academic Search

Bioluminescence recording of Ca2+ signals with the photoprotein aequorin does not require radiative energy input and can be measured with a low background and good temporal resolution. Shifting aequorin emission to longer wavelengths occurs naturally in the jellyfish Aequorea victoria by bioluminescence resonance energy transfer (BRET) to the green fluorescent protein (GFP). This process has been reproduced in the molecular

Adil Bakayan; Cecilia F. Vaquero; Fernando Picazo; Juan Llopis; Vadim E. Degtyar

2011-01-01

311

Marine & Other Invertebrates. Animal Life in Action[TM]. Schlessinger Science Library. [Videotape].  

ERIC Educational Resources Information Center

|This 23-minute videotape for grades 5-8, presents the myriad of animal life that exists on the planet. Students can view and perform experiments and investigations that help explain animal traits and habits. Invertebrate animals include a vast array of spineless creatures. In this video, students discover marine lifeforms such as jellyfish,…

2000

312

An experimental study of voice-coil driven synthetic jet propulsion for underwater vehicles  

Microsoft Academic Search

This paper investigates the thrust and flow structures produced by submerged synthetic jet actuators. Inspired by the propulsion methods of many sea creatures, such as jellyfish, squids, and salps; synthetic jets use vortex rings to create a net thrust. To assess the potential usability of these thrusters for propulsion and maneuvering of small underwater vehicles, a range of synthetic jet

A. M. Polsenberg-Thomas; Joel Burdick; Kamran Mohseni

2005-01-01

313

ClanTox: a classifier of short animal toxins  

Microsoft Academic Search

Toxins are detected in sporadic species along the evolutionary tree of the animal kingdom. Venomous animals include scorpions, snakes, bees, wasps, frogs and numerous animals living in the sea such as the stonefish, snail, jellyfish, hydra and more. Interestingly, proteins that share a common scaffold with animal toxins also exist in non-venomous spe- cies. However, due to their short length

Guy Naamati; Manor Askenazi; Michal Linial

2009-01-01

314

Developmental regulation of the growth plate  

Microsoft Academic Search

Vertebrates do not look like jellyfish because the bones of their skeletons are levers that allow movement and protect vital organs. Bones come in an enormous variety of shapes and sizes to accomplish these goals, but, with few exceptions, use one process - endochondral bone formation - to generate the skeleton. The past few years have seen an enormous increase

Henry M. Kronenberg

2003-01-01

315

Green fluorescent protein as a vital marker for non-destructive detection of transformation events in transgenic plants  

Microsoft Academic Search

Transformation of plants is a popular tool for modifying various desirable traits. Marker genes, like those encoding for bacterial ?-glucuronidase (GUS), firefly luciferase (LUC) or jellyfish green fluorescent protein (GFP) have been shown to be very useful for establishing of efficient transformation protocols. Due to favourable properties such as no need of exogenous substrates and easy visualization, GFP has been

Marek Hraška; Slavomír Rakouský; Vladislav ?urn

2006-01-01

316

Labeling Neural Cells Using Adenoviral Gene Transfer of Membrane-Targeted GFP  

Microsoft Academic Search

We describe an experimental system to visualize the soma and processes of mammalian neurons and glia in living and fixed preparations by using a recombinant adenovirus vector to transfer the jellyfish green fluorescent protein (GFP) into postmitotic neural cells both in vitro and in vivo. We have introduced several modifications of GFP that enhance its fluorescence intensity in mammalian axons

Koki Moriyoshi; Linda J Richards; Chihiro Akazawa; Dennis D. M O'Leary; Shigetada Nakanishi

1996-01-01

317

Engineering Cowpea Mosaic Virus RNA2 into a Vector to Express Heterologous Proteins in Plants  

Microsoft Academic Search

A series of new cowpea mosaic virus (CPMV) RNA-2-based expression vectors were designed. The jellyfish green fluorescent protein (GFP) was introduced between the movement protein (MP) and the large (L) coat protein or downstream of the small (S) coat protein. Release of the GFP inserted between the MP and L proteins was achieved by creating artificial processing sites each side

Kodetham Gopinath; Joan Wellink; Claudine Porta; Kathryn M. Taylor; George P. Lomonossoff; Ab van Kammen

2000-01-01

318

SHOCKING TAILS IN THE MAJOR MERGER ABELL 2744  

SciTech Connect

We identify four rare 'jellyfish' galaxies in Hubble Space Telescope imagery of the major merger cluster Abell 2744. These galaxies harbor trails of star-forming knots and filaments which have formed in situ in gas tails stripped from the parent galaxies, indicating they are in the process of being transformed by the environment. Further evidence for rapid transformation in these galaxies comes from their optical spectra, which reveal starburst, poststarburst, and active galactic nucleus features. Most intriguingly, three of the jellyfish galaxies lie near intracluster medium features associated with a merging 'Bullet-like' subcluster and its shock front detected in Chandra X-ray images. We suggest that the high-pressure merger environment may be responsible for the star formation in the gaseous tails. This provides observational evidence for the rapid transformation of galaxies during the violent core passage phase of a major cluster merger.

Owers, Matt S.; Couch, Warrick J. [Center for Astrophysics and Supercomputing, Swinburne University of Technology, Hawthorn, VIC 3122 (Australia); Nulsen, Paul E. J.; Randall, Scott W., E-mail: mowers@aao.gov.au [Harvard Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

2012-05-01

319

Advances in fluorescent protein technology.  

PubMed

Current fluorescent protein (FP) development strategies are focused on fine-tuning the photophysical properties of blue to yellow variants derived from the Aequorea victoria jellyfish green fluorescent protein (GFP) and on the development of monomeric FPs from other organisms that emit in the yellow-orange to far-red regions of the visible light spectrum. Progress toward these goals has been substantial, and near-infrared emitting FPs may loom over the horizon. The latest efforts in jellyfish variants have resulted in new and improved monomeric BFP, CFP, GFP and YFP variants, and the relentless search for a bright, monomeric and fast-maturing red FP has yielded a host of excellent candidates, although none is yet optimal for all applications. Meanwhile, photoactivatable FPs are emerging as a powerful class of probes for intracellular dynamics and, unexpectedly, as useful tools for the development of superresolution microscopy applications. PMID:18057027

Shaner, Nathan C; Patterson, George H; Davidson, Michael W

2007-12-15

320

A fluid mechanical model for mixing in a plankton predator-prey system  

NASA Astrophysics Data System (ADS)

A Lagrangian method is developed to study mixing of small particles in open flows. Particle Lagrangian Coherent Structures (pLCS) are identified as transport barriers in the dynamical systems of particles. We apply this method to a planktonic predator-prey system in which moon jellyfish Aurelia aurita uses its body motion to generate fluid currents which carry their prey to the vicinity of their capture appendages. With the flow generated by the jellyfish experimentally measured and the dynamics of prey particles in the flow described by a modified Maxey-Riley equation, we use pLCS to identify the capture region in which prey can be captured. The properties of the capture region enable analysis of the effects of several physiological and mechanical parameters on the predator-prey interaction, such as prey size, escape force, predator perception, etc. The method provides a new methodology to study dynamics and mixing of small organisms in general.

Peng, J.; Dabiri, J. O.

2009-04-01

321

Ocean Life for Kids  

NSDL National Science Digital Library

This website provides a variety of photos and text to teach students about life in the oceans. Various animals discussed include fish, sharks, dolphins, octopus, starfish, eels, lobster and jellyfish. Students choose an animal to look at, view some facts about that animal, and then answer questions based on the information given. The objective is for young elementary students to be able to distinguish amoung types of ocean life and what makes them unique.

322

Ecological insights into the polyp stage of non-native hydrozoans in the San Francisco Estuary  

Microsoft Academic Search

The populations of several invasive jellyfish appear to be increasing around the globe. While data on non-native hydromedusae\\u000a in the San Francisco Estuary have been accumulating in recent years, little is known regarding their polyp phase. The goal\\u000a of this study was to gather the first field-derived ecological data for polyp stages of Blackfordia virginica, Moerisia sp., and Cordylophora caspia

Alpa P. WintzerMariah; Mariah H. Meek; Peter B. Moyle; Bernie May

2011-01-01

323

Naked Axons and Symmetrical Synapses in an Elementary Nervous System  

Microsoft Academic Search

THE animals of the phylum Coelenterata, which includes the anemones, corals and jellyfish, are the simplest animals with undoubted nervous tissue, which is morphologically similar to that of higher animals1, and which has all-or-none impulses accompanied by a typical action potential2. The nervous system is peculiar in being arranged mainly as a network, but in medusæ some neurones form strands

G. A. Horridge

1962-01-01

324

The cnidarian nematocyst: a miniature extracellular matrix within a secretory vesicle  

Microsoft Academic Search

Nematocysts are the taxon-defining features of all cnidarians including jellyfish, sea anemones, and corals. They are highly\\u000a sophisticated organelles used for the capture of prey and defense. The nematocyst capsule is produced within a giant post-Golgi\\u000a vesicle, which is continuously fed by proteins from the secretory pathway. Mature nematocysts consist of a hollow capsule\\u000a body in which a long tubule

Suat Özbek

325

EvoD\\/Vo: the origins of BMP signalling in the neuroectoderm  

Microsoft Academic Search

The genetic systems controlling body axis formation trace back as far as the ancestor of diploblasts (corals, hydra, and jellyfish) and triploblasts (bilaterians). Comparative molecular studies, often referred to as evo–devo, provide powerful tools for elucidating the origins of mechanisms for establishing the dorsal–ventral and anterior–posterior axes in bilaterians and reveal differences in the evolutionary pressures acting upon tissue patterning.

Claudia Mieko Mizutani; Ethan Bier

2008-01-01

326

The antibody response in seabather's eruption.  

PubMed

Thirty-six of 44 patients with seabather's eruption had specific IgG antibodies against Linuche unguilata (thimble jelly) medusae antigen. ELISA detected antibodies in serum stored for 10 years. The extent of the cutaneous eruption or sting severity was correlated with antibody titer. Antibodies were detected in patients acquiring the eruption in Florida, the Bahamas and Aruba, reflecting the habitat of these jellyfish. This serological assay can be useful to confirm the clinical diagnosis. PMID:7778134

Burnett, J W; Kumar, S; Malecki, J M; Szmant, A M

1995-01-01

327

Cell-to-Cell and Long-Distance Trafficking of the Green Fluorescent Protein in the Phloem and Symplastic Unloading of the Protein into Sink Tissues  

Microsoft Academic Search

Macromolecular trafficking within the sieve element-companion cell complex, phloem unloading, and post-phloem transport were studied using the jellyfish green fluorescent protein (GFP). The GFP gene was expressed in Arabidopsis and tobacco under the control of the AtSUC2 promoter. In wild-type Arabidopsis plants, this promoter regulates ex- pression of the companion cell-specific AtSUC2 sucrose-H 1 symporter gene. Analyses of the AtSUC2

Astrid Imlau; Elisabeth Truernit; Norbert Sauer

1999-01-01

328

Water vs. Land  

NSDL National Science Digital Library

This activity, created to accompany the museum's Milstein Hall of Ocean Life, gives students a hands-on look at how some ocean creatures rely on buoyancy for external support. The activity starts with a class discussion in which students ponder how their lives would be different if they lived in water. Then, using plastic baggies filled with water to represent jellyfish, they examine how these creatures without "organic support" rely on buoyancy.

329

Cyanea capillata tentacle-only extract as a potential alternative of nematocyst venom: Its cardiovascular toxicity and tolerance to isolation and purification procedures  

Microsoft Academic Search

As the proteins with cardiovascular toxicity in jellyfish nematocyst venom and tentacle-only extract (TOE) are probably encoded by the same gene, TOE provides a potential alternative of nematocyst venom with much richer source for acquisition of such proteins. In this study, Cyanea capillata nematocyst venom and TOE (5mg\\/kg) both exhibited cardiovascular toxicity in rats, and TOE caused blood pressure reduction

Liang Xiao; Qian He; Yufeng Guo; Jing Zhang; Fei Nie; Yue Li; Xiaofei Ye; Liming Zhang

2009-01-01

330

Human glucocorticoid receptor isoform ?: recent understanding of its potential implications in physiology and pathophysiology  

Microsoft Academic Search

The human glucocorticoid receptor (GR) gene expresses two splicing isoforms ? and ? through alternative use of specific exons\\u000a 9? and 9?. In contrast to the classic receptor GR?, which mediates most of the known actions of glucocorticoids, the functions\\u000a of GR? have been largely unexplored. Owing to newly developed methods, for example microarrays and the jellyfish fluorescence\\u000a proteins, we

Tomoshige Kino; Yan A. Su; George P. Chrousos

2009-01-01

331

Characterization of fission yeast meiotic mutants based on live observation of meiotic prophase nuclear movement  

Microsoft Academic Search

.   We characterized four meiotic mutants of the fission yeast Schizosaccharomyces pombe by live observation of nuclear movement. Nuclei were stained with either the DNA-specific fluorescent dye Hoechst 33342 or\\u000a jellyfish green fluorescent protein (GFP) fused with the N-terminal portion of DNA polymerase ?. We first followed nuclear\\u000a dynamics in wild-type cells to determine the temporal sequence of meiotic events:

Yasushi Hiraoka; Da-Qiao Ding; Ayumu Yamamoto; Chihiro Tsutsumi; Yuji Chikashige

2000-01-01

332

Wavelength Mutations and Posttranslational Autoxidation of Green Fluorescent Protein  

Microsoft Academic Search

The green fluorescent protein (GFP) of the jellyfish Aequorea victoria is an unusual protein with strong visible absorbance and fluorescence from a p-hydroxybenzylidene-imidazolidinone chromophore, which is generated by cyclization and oxidation of the protein's own Ser-Tyr-Gly sequence at positions 65-67. Cloning of the cDNA and heterologous expression of fluorescent protein in a wide variety of organisms indicate that this unique

Roger Heim; Douglas C. Prasher; Roger Y. Tsien

1994-01-01

333

Dynamic Modeling and Control of Biologically Inspired Vortex Ring Thrusters for Underwater Robot Locomotion  

Microsoft Academic Search

A new type of underwater thruster was designed to provide high-accuracy, low-speed maneuvering to underwater robots. Located internal to the vehicle surface, these thrusters have a minimal effect on the forward-drag profile of the vehicle. These thrusters, whose inspiration comes from the natural propulsion of cephalopods and jellyfish, generate control forces by successive ingestion and expulsion of jets of water

Michael Krieg; Kamran Mohseni

2010-01-01

334

Cutaneous injuries from marine animals.  

PubMed

Cutaneous injuries by marine animals have a myriad of clinical presentations. Most require only symptomatic treatment, but some may be limb-threatening or even fatal. This is a report of three cases of marine animal injuries by a stingray, a sea anemone and a jellyfish, respectively, illustrating the potential severity of such injuries. The importance of early diagnosis is emphasised, with a discussion on the management of injuries from these three types of marine animals. PMID:17245501

Lim, Y L; Kumarasinghe, S P W

2007-01-01

335

Field and laboratory observations on predation and prey selectivity of the scyphomedusa Chrysaora cf. caliparea in Southeast Indian waters  

Microsoft Academic Search

Chrysaora cf. caliparea, one of the most abundant medusae species in India, seems to be an important predator in the coastal waters of Bay of Bengal.\\u000a The ability of Chrysaora cf. caliparea to feed at maximum rate in high prey concentrations implies that this jellyfish can efficiently exploit dense prey patches,\\u000a at least for a short period. This study presents

Govindan Kanagaraj; Pazhaniyappan Ezhilarasan; Pitchai Sampathkumar; André C. Morandini; Velayudhan pillai Sivakumar

2011-01-01

336

Blind sea creature hunts with a light  

NSDL National Science Digital Library

The deep sea is a seriously dark place, so when a light shows up, even a tiny one, fish will swim up for a closer look. That seems to be the strategy behind the glowing red spots used by a relative of the jellyfish, called Erenna. Scientists have just discovered that these creatures have glowing red dots in their tentacles, which are probably used to lure fishy prey.

American Association for the Advancement of Science (AAAS;)

2005-07-07

337

Crystal structure of bacterial multidrug efflux transporter AcrB  

Microsoft Academic Search

AcrB is a major multidrug exporter in Escherichia coli. It cooperates with a membrane fusion protein, AcrA, and an outer membrane channel, TolC. We have determined the crystal structure of AcrB at 3.5Å resolution. Three AcrB protomers are organized as a homotrimer in the shape of a jellyfish. Each protomer is composed of a transmembrane region 50Å thick and a

Satoshi Murakami; Ryosuke Nakashima; Eiki Yamashita; Akihito Yamaguchi

2002-01-01

338

Spatio-temporal foraging patterns of a giant zooplanktivore, the leatherback turtle  

Microsoft Academic Search

Understanding food web functioning through the study of natural bio-indicators may constitute a valuable and original approach. In the context of jellyfish proliferation in many overexploited marine ecosystems studying the spatio-temporal foraging patterns of the giant “jellyvore” leatherback turtle turns out to be particularly relevant. Here we analyzed long-term tracking data to assess spatio-temporal foraging patterns in 21 leatherback turtles

Sabrina Fossette; Victoria J. Hobson; Charlotte Girard; Beatriz Calmettes; Philippe Gaspar; Jean-Yves Georges; Graeme C. Hays

2010-01-01

339

A New Method for the Separation of Different Types of Nematocysts from Scyphozoa and Investigation of Proteinaceous Toxins Utilizing Laser Catapulting and Subsequent Mass Spectrometry  

Microsoft Academic Search

Jellyfish have an increasing impact on marine ecology. Cnidocysts bearing stinging cells afford, amongst others, prey capture\\u000a and defence. Several different types of stinging capsules are found in one species and they are supposed to have specific\\u000a functions, e.g. paralysing prey or adhering to it. Due to these assumed different roles of the capsules, it is suggested that\\u000a toxins, which

Annika Wiebring; Heike Helmholz; Ilka Sötje; Stephan Lassen; Andreas Prange; Henry Tiemann

2010-01-01

340

Redistribution of membrane proteins between the Golgi apparatus and endoplasmic reticulum in plants is reversible and not dependent on cytoskeletal networks  

Microsoft Academic Search

Summary We have fused the signal anchor sequences of a rat sialyl transferase and a human galactosyl transferase along with the Arabidopsis homologue of the yeast HDEL receptor (AtERD2) to the jellyfish green fluorescent protein (GFP) and transiently expressed the chimeric genes in tobacco leaves. All constructs targeted the Golgi apparatus and co-expression with DsRed fusions along with immunolabelling of

Claude M. Saint-Jore; Janet Evins; Henri Batoko; Federica Brandizzi; Ian Moore; Chris Hawes

2002-01-01

341

Photo-Induced Peptide Cleavage in the Green-to-Red Conversion of a Fluorescent Protein  

Microsoft Academic Search

Green fluorescent protein from the jellyfish (Aequorea GFP) and GFP-like proteins from coral species encode light-absorbing chromophores within their protein sequences. A coral fluorescent protein, Kaede, contains a tripeptide, His62-Tyr63-Gly64, which acts as a green chromophore that is photoconverted to red. Here, we present the structural basis for the green-to-red photoconversion. As in Aequorea GFP, a chromophore, 4-(p-hydroxybenzylidene)-5-imidazolinone, derived from

Hideaki Mizuno; Tapas Kumar Mal; Kit I. Tong; Ryoko Ando; Toshiaki Furuta; Mitsuhiko Ikura; Atsushi Miyawaki

2003-01-01

342

The crystal structure of the photoprotein aequorin at 2.3 Å resolution  

Microsoft Academic Search

Aequorin is a calcium-sensitive photoprotein originally obtained from the jellyfish Aequorea aequorea. Because it has a high sensitivity to calcium ions and is biologically harmless, aequorin is widely used as a probe to monitor intracellular levels of free calcium. The aequorin molecule contains four helix-loop-helix `EF-hand' domains, of which three can bind calcium. The molecule also contains coelenterazine as its

James F. Head; Satoshi Inouye; Katsunori Teranishi; Osamu Shimomura

2000-01-01

343

Duplication and Quadruplication of Arabidopsis thaliana Cysteinyl and Asparaginyl-tRNA Synthetase Genes of Organellar Origin  

Microsoft Academic Search

.   Two cysteinyl-tRNA synthetases (CysRS) and four asparaginyl-tRNA synthetases (AsnRS) from Arabidopsis thaliana were characterized from genome sequence data, EST sequences, and RACE sequences. For one CysRS and one AsnRS, sequence alignments\\u000a and prediction programs suggested the presence of an N-terminal organellar targeting peptide. Transient expression of these\\u000a putative targeting sequences joined to jellyfish green fluorescent protein (GFP) demonstrated that

Nemo M. Peeters; Anne Chapron; Anatoli Giritch; Olivier Grandjean; Dominique Lancelin; Tatiana Lhomme; Arnaud Vivrel; Ian Small

2000-01-01

344

Endobiotic bacteria and their pathogenic potential in cnidarian tentacles  

Microsoft Academic Search

Endobiotic bacteria colonize the tentacles of cnidaria. This paper provides first insight into the bacterial spectrum and\\u000a its potential of pathogenic activities inside four cnidarian species. Sample material originating from Scottish waters comprises\\u000a the jellyfish species Cyanea capillata and C. lamarckii, hydrozoa Tubularia indivisa and sea anemone Sagartia elegans. Mixed cultures of endobiotic bacteria, pure cultures selected on basis of

Christian Schuett; Hilke Doepke

2010-01-01

345

WHAT EXACTLY IS IT THAT SLEEPS? : THE EVOLUTION, REGULATION AND ORGANIZATION OF AN EMERGENT NETWORK PROPERTY  

Microsoft Academic Search

ABSTRACT ,It is posited that sleep is a network-emergentpropert y of any viable group of interconnected neurons. Animals ranging from jellyfish to all homeotherms,sleep. Biochemical sleep regulatory events, including cytokines and nuclear factor kappa B (NFkB) are shared by insects and mammals. Itseems,likely that these sleep regulatory events evolved from metabolic regulatory events and that sleep is a local use-dependent

James M. Krueger

346

[Dermatotoxicity caused by Chrysaora hysoscella. Presentation of a case].  

PubMed

Chrysaora hysoscella L. rarely occurs in coastal waters of the Adriatic sea and is usually considered an innocuous jellyfish. In June 1989, P.D.N., a 29 year old healthy female, biologist at the Marine Biology Laboratory of Trieste, treated some samples of Chrysaora hysoscella captured that day. She took the animals from the transport tanks and cut the tentacles and oral arms from their bell. About ten minutes later she felt itching and burning of her hands, especially the right one. Twenty minutes later erythematous and slightly edematous lesions appeared on her fingers. These lesions spontaneously disappeared in about 2 hours. We decided to test Chrysaora hysoscella dermotoxicity on healthy volunteers by cutting a Chrysaora hysoscella tentacle and placing it on a gauze soaked in a solution of 3% NaCl and applying then to the volar side of the right wrist for one minute. Both volunteers presented itching and burning within forty seconds of contact. Three minutes later erythematous and vesicular lesions appeared on the sting site. To the best of our knowledge this is the second reported but first documented report of the dermotoxic effect of Chrysaora hysoscella. We underline that the absence of other previous reports may be due to both the relative rarity of this jellyfish and to the fact that people often confuses Chrysaora hysoscella with other more common jellyfish. PMID:2576554

Kokelj, F; Del Negro, P; Tubaro, A

1989-06-01

347

Bio-inspired unmanned undersea vehicle  

NASA Astrophysics Data System (ADS)

Biological systems in ocean environment provide all the desired features required for design of unmanned undersea vehicles. We noticed the uniqueness and simplicity in the design of rowing medusa and have successfully demonstrated working prototypes of Aurelia Aurita. In this study, we demonstrate the effect of bell joints in reducing the contraction force required for deformation. The study is based on observations made for the sub-umbrella features of jellyfish. Artificial jellyfish unmanned undersea vehicle (UUV) was fabricated consisting of silicone as the matrix material and shape memory alloy (SMA) as the actuation material. UUV was characterized for its performance and tailored to achieve vertical motion. SMAs were selected for actuation material because they are simple current-driven device providing large strain and blocking force. However, electrical power requirements were found to be quite high in the underwater conditions. It was identified that by including "joints" in the structural material forming the bell, the overall power requirement can be reduced as it lowers the resistance to compression. An analytical model was developed that correlates the deformation achieved with the morphology of the joints. Experiments were conducted to characterize the effect of both joint shapes and structural materials on the motion. Results are compared with that of natural medusa gastrodermal lamella and analyzed using the theoretical model. By including the features inherently present in natural jellyfish, the required compression force was found to be decreased.

Smith, Colin F.; Priya, Shashank

2010-03-01

348

Australian orchids and the doctors they commemorate.  

PubMed

Botanical taxonomy is a repository of medical biographical information. Such botanical memorials include the names of some indigenous orchids of Australia. By searching reference texts and journals relating to Australian botany and Australian orchidology, as well as Australian and international medical and botanical biographical texts, I identified 30 orchids indigenous to Australia whose names commemorate doctors and other medical professionals. Of these, 24 have names that commemorate a total of 16 doctors who worked in Australia. The doctors and orchids I identified include: doctor-soldiers Richard Sanders Rogers (1862-1942), after whom the Rogers' Greenhood (Pterostylis rogersii) is named, and Robert Brown (1773-1858), after whom the Purple Enamel Orchid (Elythranthera brunonis) is named; navy surgeon Archibald Menzies (1754-1842), after whom the Hare Orchid (Leptoceras menziesii) is named; radiologist Hugo Flecker (1884-1957) after whom the Slender Sphinx Orchid (Cestichis fleckeri) is named; and general medical practitioner Hereward Leighton Kesteven (1881-1964), after whom the Kesteven's Orchid (Dendrobium kestevenii) is named. Biographic references in scientific names of plants comprise a select but important library of Australian medical history. Such botanical taxonomy commemorates, in an enduring manner, clinicians who have contributed to biology outside clinical practice. PMID:23330773

Pearn, John H

2013-01-21

349

Lagrangian coherent structures in low Reynolds number swimming  

NASA Astrophysics Data System (ADS)

This work explores the utility of the finite-time Lyapunov exponent (FTLE) field for revealing flow structures in low Reynolds number biological locomotion. Previous studies of high Reynolds number unsteady flows have demonstrated that ridges of the FTLE field coincide with transport barriers within the flow, which are not shown by a more classical quantity such as vorticity. In low Reynolds number locomotion (O(1)-O(100)), in which viscous diffusion rapidly smears the vorticity in the wake, the FTLE field has the potential to add new insight to locomotion mechanics. The target of study is an articulated two-dimensional model for jellyfish-like locomotion, with swimming Reynolds number of order 1. The self-propulsion of the model is numerically simulated with a viscous vortex particle method, using kinematics adapted from previous experimental measurements on a live medusan swimmer. The roles of the ridges of the computed forward- and backward-time FTLE fields are clarified by tracking clusters of particles both backward and forward in time. It is shown that a series of ridges in front of the jellyfish in the forward-time FTLE field transport slender fingers of fluid toward the lip of the bell orifice, which are pulled once per contraction cycle into the wake of the jellyfish, where the fluid remains partitioned. A strong ridge in the backward-time FTLE field reveals a persistent barrier between fluid inside and outside the subumbrellar cavity. The system is also analyzed in a body-fixed frame subject to a steady free stream, and the FTLE field is used to highlight differences in these frames of reference.

Wilson, Megan M.; Peng, Jifeng; Dabiri, John O.; Eldredge, Jeff D.

2009-05-01

350

Selective toxin-lipid membrane interactions of natural, haemolytic Scyphozoan toxins analyzed by surface plasmon resonance.  

PubMed

A comparison of the molecular interaction of natural Scyphozoan lysins with their bioactivity in a haemolytic assay was performed by establishing an efficient, automatable and reproducible procedure for the measurement of protein-membrane interactions. The toxin-membrane interactions were analyzed utilising a chip-based technology with immobilized liposomes as artificial cell membranes. The technique was established with streptolysin O as a cholesterol-selective model toxin and its cholesterol-selectivity has been proven. The haemolytic potency of protein fractions derived from the venom of the jellyfish Aurelia aurita and Cyanea capillata was tested and EC50 values of 35.3mug/mL and 43.1mug/mL against sheep and 13.5mug/mL and 8.8mug/mL against rabbit erythrocytes were measured. Cell membrane binding as a first step in the haemolytic process was analyzed using the Biacore((R)) technology. Major cell membrane lipids (cholesterol, sphingomyelin and phosphatidylcholine) were immobilized as pure liposomes and in binary mixtures. A preference for cholesterol and sphingomyelin of both jellyfish species was demonstrated. The specificity of the method was proven with a non-haemolytic A. aurita protein fraction that did not express a lipid binding. Additionally, an inactivated C. capillata lysine with negligible haemolytic activity showed a remaining but reduced adsorption onto lipid layers. The binding level of the lytic venom fraction of these dominant boreal jellyfish species increased as a function of protein concentration. The binding strength was expressed in RU50 values ranging from 12.4mug/mL to 35.4mug/mL, which were in the same order of magnitude as the EC50 values in the haemolytic assay. PMID:20599534

Helmholz, Heike

2010-06-25

351

Effect of sub-lethal exposure to ultraviolet radiation on the escape performance of Atlantic cod larvae (Gadus morhua).  

PubMed

The amount of ultraviolet (UV) radiation reaching the earth's surface has increased due to depletion of the ozone layer. Several studies have reported that UV radiation reduces survival of fish larvae. However, indirect and sub-lethal impacts of UV radiation on fish behavior have been given little consideration. We observed the escape performance of larval cod (24 dph, SL: 7.6±0.2 mm; 29 dph, SL: 8.2±0.3 mm) that had been exposed to sub-lethal levels of UV radiation vs. unexposed controls. Two predators were used (in separate experiments): two-spotted goby (Gobiusculus flavescens; a suction predator) and lion's mane jellyfish (Cyanea capillata; a "passive" ambush predator). Ten cod larvae were observed in the presence of a predator for 20 minutes using a digital video camera. Trials were replicated 4 times for goby and 5 times for jellyfish. Escape rate (total number of escapes/total number of attacks ×100), escape distance and the number of larvae remaining at the end of the experiment were measured. In the experiment with gobies, in the UV-treated larvae, both escape rate and escape distance (36%, 38±7.5 mm respectively) were significantly lower than those of control larvae (75%, 69±4.7 mm respectively). There was a significant difference in survival as well (UV: 35%, Control: 63%). No apparent escape response was observed, and survival rate was not significantly different, between treatments (UV: 66%, Control: 74%) in the experiment with jellyfish. We conclude that the effect and impact of exposure to sub-lethal levels of UV radiation on the escape performance of cod larvae depends on the type of predator. Our results also suggest that prediction of UV impacts on fish larvae based only on direct effects are underestimations. PMID:22536406

Fukunishi, Yuichi; Browman, Howard I; Durif, Caroline M F; Bjelland, Reidun M; Skiftesvik, Anne Berit

2012-04-19

352

Effect of Sub-Lethal Exposure to Ultraviolet Radiation on the Escape Performance of Atlantic Cod Larvae (Gadus morhua)  

PubMed Central

The amount of ultraviolet (UV) radiation reaching the earth's surface has increased due to depletion of the ozone layer. Several studies have reported that UV radiation reduces survival of fish larvae. However, indirect and sub-lethal impacts of UV radiation on fish behavior have been given little consideration. We observed the escape performance of larval cod (24 dph, SL: 7.6±0.2 mm; 29 dph, SL: 8.2±0.3 mm) that had been exposed to sub-lethal levels of UV radiation vs. unexposed controls. Two predators were used (in separate experiments): two-spotted goby (Gobiusculus flavescens; a suction predator) and lion's mane jellyfish (Cyanea capillata; a “passive" ambush predator). Ten cod larvae were observed in the presence of a predator for 20 minutes using a digital video camera. Trials were replicated 4 times for goby and 5 times for jellyfish. Escape rate (total number of escapes/total number of attacks ×100), escape distance and the number of larvae remaining at the end of the experiment were measured. In the experiment with gobies, in the UV-treated larvae, both escape rate and escape distance (36%, 38±7.5 mm respectively) were significantly lower than those of control larvae (75%, 69±4.7 mm respectively). There was a significant difference in survival as well (UV: 35%, Control: 63%). No apparent escape response was observed, and survival rate was not significantly different, between treatments (UV: 66%, Control: 74%) in the experiment with jellyfish. We conclude that the effect and impact of exposure to sub-lethal levels of UV radiation on the escape performance of cod larvae depends on the type of predator. Our results also suggest that prediction of UV impacts on fish larvae based only on direct effects are underestimations.

Fukunishi, Yuichi; Browman, Howard I.; Durif, Caroline M. F.; Bjelland, Reidun M.; Skiftesvik, Anne Berit

2012-01-01

353

Venomous bites, stings, and poisoning.  

PubMed

This article discusses the epidemiology, prevention, clinical features, first aid and medical treatment of venomous bites by snakes, lizards, and spiders; stings by fish, jellyfish, echinoderms, and insects; and poisoning by fish and molluscs, in all parts of the world. Of these envenoming and poisonings, snake bite causes the greatest burden of human suffering, killing 46,000 people each year in India alone and more than 100,000 worldwide and resulting in physical handicap in many survivors. Specific antidotes (antivenoms/antivenins) are available to treat envenoming by many of these taxa but supply and distribution is inadequate in many tropical developing countries. PMID:22632635

Warrell, David A

2012-04-24

354

A PC-based spreadsheet for tracking results of crystallization experiments  

NASA Astrophysics Data System (ADS)

Crystallization of proteins often involves many individual experiments entailing a great deal of recordkeeping. A method is used in our laboratory to track crystallization experiments with a commercially available spreadsheet program and an 80286 microprocessor-based personal computer (PC). The system takes advantage of a windowing environment. Results are entered directly into the spreadsheet as experiments are examined. The data are stored and later analyzed. They are sorted by pertinent fields and analyzed for significant trends. New experiments are then designed based upon these results. We have prepared crystals of several proteins, including the photoprotein aequorin, from the jellyfishAequorea, in part by using information obtained from this tracking system.

Hannick, L. I.; Perozzo, M. A.; Schultz, L. W.; Ward, K. B.

1992-08-01

355

Medical grand rounds. West Virginia University Health Sciences Center. Bites and stings. Part 1. Spiders.  

PubMed

Most animals can bite or sting. In narrowing the kingdom down to those that harm humans, the field still is vast. It would be interesting to explore the rich variety of pathology produced in us by moray eels, lionfish, sea urchins, jellyfish, sting rays, fire ants, kissing bugs, flies, lice, mosquitoes, ticks, mites, fleas, puss caterpillars, centipedes, snakes, dogs and cats, camels, and myriad other creatures including homo sapiens (not a trivial biter)--but for this grand rounds, the topic will simply be spiders (Part 1), bees and vespid (Part 2). Vespids are the wasps, yellow jackets and hornets. PMID:2718467

Ullrich, I H

1989-04-01

356

Lagrangian Coherent Structures for Inertial Particles  

NASA Astrophysics Data System (ADS)

In this talk, I will discuss recent results on the asymptotics of inertial (i.e., finite-size) particle motion. The asymptotic particle motion turns out to be governed by a slow manifold that can be constructed explicitly up to any order of precision. Particle motions synchronize with inertial Lagrangian coherent structures (ILCS) obtained from the reduced dynamics on the slow manifold. For larger particle sizes, the slow manifold develops local instabilities that can be located analytically. As applications, I discuss droplet motion in hurricanes, source inversion for contaminants in an urban environment, and predator-prey interaction in jellyfish feeding.

Haller, G.; Sapsis, T.

2009-04-01

357

Molecular Structure of Salinamide B  

NSDL National Science Digital Library

Salinamide B is produced by the marine bacterium Streptomyces, an actinomycete that has been isolated from the surface of the jellyfish Cassiopeia xamachana, collected from the Florida Keys. Salinamide B shows moderate antibiotic activity against Gram-positive bacteria and exhibits potent topical anti-inflammatory activity. The biosynthesis of salinamide is currently being studied with hopes of generating unnatural salinamide analogues, which would be used to further understand its anti-inflammatory properties. Salinamide is thought to be a possible contender in the treatment of some forms of arthritis.

2003-04-10

358

Lagrangian coherent structures and the smallest finite-time Lyapunov exponent  

NASA Astrophysics Data System (ADS)

We point out that local minimizing curves, or troughs, of the smallest finite-time Lyapunov exponent (FTLE) field computed over a time interval [t0, t] and graphed over trajectory positions at time t mark attracting Lagrangian coherent structures (LCSs) at t. For two-dimensional area-preserving flows, we conclude that computing the largest forward-time FTLE field by itself is sufficient for locating both repelling LCSs at t0 and attracting LCSs at t. We illustrate our results on analytic examples, as well as on a two-dimensional experimental velocity field measured near a swimming jellyfish.

Haller, George; Sapsis, Themistoklis

2011-06-01

359

Global Climate Change : The Ross Ice Shelf  

NSDL National Science Digital Library

This video lecture explores the effects of climate change on the Ross Ice Shelf in Antarctica. Slides depict how a large iceberg fell off the Ross Ice Shelf in March 2000. The lecturer describes his expedition to the ice shelf shortly after this event. He describes dives conducted to observe the underwater ecosystems containing krill and jellyfish, and the ocean currents around the icebergs. Facts about the icebergs in Antarctica are presented, and the sensitivity of polar regions to climate is explained. The video is 14 minutes in length.

2007-12-12

360

Fish Stories  

NSDL National Science Digital Library

This 48 minute radio broadcast contains three fish tales. First discussed is the fact that researchers have found that much of the fish sold as red snapper in the United States may actually be something else. The show explores the unusual behavior of the midshipman fish, which hums to attract a mate. New research indicates a connection between the hormone levels in the female of the species and its ability to hear the humming males. Finally, the show discusses jellyfish, and whether jelly blooms have an environmental significance.

361

Global Climate Change: The Ross Ice Shelf  

NSDL National Science Digital Library

This video lecture explores the effects of climate change on the Ross Ice Shelf in Antarctica. Slides depict how a large iceberg fell off the Ross Ice Shelf in March 2000. The lecturer describes his expedition to the ice shelf shortly after this event. He describes dives conducted to observe the underwater ecosystems containing krill and jellyfish, and the ocean currents around the icebergs. Facts about the icebergs in Antarctica are presented, and the sensitivity of polar regions to climate is explained. The video is 14 minutes in length.

Stone, Greg

362

Shape-changing bodies in fluid: Hovering, ratcheting, and bursting  

NASA Astrophysics Data System (ADS)

Motivated by recent experiments on the hovering of passive bodies, we demonstrate how a simple shape-changing body can hover or ascend in an oscillating background flow. We study this ratcheting effect through numerical simulations of the two-dimensional Navier-Stokes equations at intermediate Reynolds number. This effect could describe a viable means of locomotion or transport in such environments as a tidal pool with wave-driven sloshing. We also consider the velocity burst achieved by a body through a rapid increase in its aspect ratio, which may contribute to the escape dynamics of such organisms as jellyfish.

Spagnolie, Saverio E.; Shelley, Michael J.

2009-01-01

363

Ediacara Biota: Ancestors of Modern Life or Evolutionary Dead End?  

NSDL National Science Digital Library

Ediacara Biota are the first convincing fossils of Precambrian animals that were found in the Ediacara Hills of Australia. The unusual fossils, originally interpreted as jellyfish, strange worms, and frond-like corals, gave scientists their first look at the animals that populated the Precambrian seas. In Canada, Ediacaran fossils are found in the Northwest Territories, Yukon, British Columbia, and Newfoundland. The Mackenzie Mountains, NWT, has the thickest continuous section of rock (2.5 kilometers) containing Ediacaran fossils in the world. This site provides information on the fossils and features a location map with active links and a link to information on Ediacaran fossils found in Namibia.

364

The occurrence of Ophiocnemis marmorata (Echinodermata: Ophiuroidea) associated with the rhizostome medusa Rhopilema hispidum (Cnidaria: Scyphozoa)  

NASA Astrophysics Data System (ADS)

The association of scyphomedusae with invertebrates has been long known in the literature; especially with hyperiids amphipods. The association of echinoderms with jellyfish is not common and rarely recorded. We reported the association of the ophiuroid Ophiocnemis marmorata with the rhizostome scyphomedusa Rhopilema hispidum collected in Vellar estuary (on the southeast coast of India). O. marmorata is supposed to be a filter feeding ophiuroid, quite common in soft bottom of shallow waters. The brittle stars possibly seek for food supply, shelter and protection through the association.

Kanagaraj, Govindan; Kumar, Pithchai Sampath; Morandini, André C.

2008-11-01

365

[Arthropod bite reactions and pyodermias].  

PubMed

Tourists in the tropics often develop reactions to bites or stings of mosquitoes, fleas, mites, ants, bedbugs, beetles, larva, millipedes, spiders and scorpions. In addition, they may have fresh or salt water exposure to sponges, corals, jellyfish and sea urchins with resultant injury and inflammation. Bacterial skin infections (pyodermias) can follow bites or stings as well as mechanical trauma. The most common bacteria involved in skin infections are staphylococci and streptococci. For tourists, bacterial infections are often complicating a pruritic bite reaction and scratching. It is important to know the cause of the bite reaction and pyoderma in order to take appropriate therapeutic measures. PMID:18626616

Hengge, U R

2008-08-01

366

Assembly of the cnidarian camera-type eye from vertebrate-like components  

PubMed Central

Animal eyes are morphologically diverse. Their assembly, however, always relies on the same basic principle, i.e., photoreceptors located in the vicinity of dark shielding pigment. Cnidaria as the likely sister group to the Bilateria are the earliest branching phylum with a well developed visual system. Here, we show that camera-type eyes of the cubozoan jellyfish, Tripedalia cystophora, use genetic building blocks typical of vertebrate eyes, namely, a ciliary phototransduction cascade and melanogenic pathway. Our findings indicative of parallelism provide an insight into eye evolution. Combined, the available data favor the possibility that vertebrate and cubozoan eyes arose by independent recruitment of orthologous genes during evolution.

Kozmik, Zbynek; Ruzickova, Jana; Jonasova, Kristyna; Matsumoto, Yoshifumi; Vopalensky, Pavel; Kozmikova, Iryna; Strnad, Hynek; Kawamura, Shoji; Piatigorsky, Joram; Paces, Vaclav; Vlcek, Cestmir

2008-01-01

367

DNA sequence organization in the genomes of five marine invertebrates.  

PubMed

The arrangement of repetitive and non-repetitive sequence was studied in the genomic DNA of the oyster (Crassostrea virginica), the surf clam (Spisula solidissima), the horseshoe crab (Limulus polyphemus), a nemertean worm (Cerebratulus lacteus) and a jelly-fish (Aurelia aurita). Except for the jellyfish these animals belong to the protostomial branch of animal evolution, for which little information regarding DNA sequence organization has previously been available. The reassociation kinetics of short (250-300 nucleotide) and long (2,000-3,000 nucleotide) DNA fragments was studied by the hydroxyapatite method. It was shown that in each case a major fraction of the DNA consists of single copy sequences less than about 3,000 nucleotides in length, interspersed with short repetitive sequences. The lengths of the repetitive sequences were estimated by optical hyperchromicity and S1 nuclease measurements made on renaturation products. All the genomes studied include a prominent fraction of interspersed repetitive sequences about 300 nucleotides in length, as well as longer repetitive sequence regions. PMID:238802

Goldberg, R B; Crain, W R; Ruderman, J V; Moore, G P; Barnett, T R; Higgins, R C; Gelfand, R A; Galau, G A; Britten, R J; Davidson, E H

1975-07-21

368

QM/MM study on the light emitters of aequorin chemiluminescence, bioluminescence, and fluorescence: a general understanding of the bioluminescence of several marine organisms.  

PubMed

Aequorea victoria is a type of jellyfish that is known by its famous protein, green fluorescent protein (GFP), which has been widely used as a probe in many fields. Aequorea has another important protein, aequorin, which is one of the members of the EF-hand calcium-binding protein family. Aequorin has been used for intracellular calcium measurements for three decades, but its bioluminescence mechanism remains largely unknown. One of the important reasons is the lack of clear and reliable knowledge about the light emitters, which are complex. Several neutral and anionic forms exist in chemiexcited, bioluminescent, and fluorescent states and are connected with the H-bond network of the binding cavity in the protein. We first theoretically investigated aequorin chemiluminescence, bioluminescence, and fluorescence in real proteins by performing hybrid quantum mechanics and molecular mechanics methods combined with a molecular dynamics method. For the first time, this study reported the origin and clear differences in the chemiluminescence, bioluminescence and fluorescence of aequorin, which is important for understanding the bioluminescence not only of jellyfish, but also of many other marine organisms (that have the same coelenterazine caved in different coelenterazine-type luciferases). PMID:23670851

Chen, Shu-Feng; Ferré, Nicolas; Liu, Ya-Jun

2013-05-13

369

Controlling pulsatile jet formation number with variable diameter exit nozzle for maximum impulse generation  

NASA Astrophysics Data System (ADS)

Both jellyfish and Squid propel themselves by ejecting high momentum vortex rings. A set of vortex ring generating thrusters were developed and tested for application in underwater vehicle propulsion. Vortex rings generated from a steady piston cylinder mechanism have a universal formation time, known as the formation number (Gharib et al. 1998), associated with reaching maximum circulation, where the vortex ring separates from its trailing shear flow. The non-dimensional jet formation time (also called the stroke ratio) plays a key role in the thrust output of the device; since thrusters operating above the formation number re-ingest the trailing jet. A variable diameter exit nozzle was used to increase the formation number of the jet to maximize thrust (which is a technique observed in squid and jellyfish locomotion). Visualization studies confirmed the ability to delay the onset of ring ``pinch-off'', using a variable nozzle, and the thrust was empirically shown to achieve a higher maximum. Additionally, a fluid slug model which was developed to predict the thrust output was adapted to incorporate a changing nozzle diameter. This model was verified with the empirical thrust data and was again shown to be accurate for stroke ratios below the formation number.

Krieg, Mike; Thomas, Tyler; Mohseni, Kamran

2009-11-01

370

Field and laboratory observations on predation and prey selectivity of the scyphomedusa Chrysaora cf. caliparea in Southeast Indian waters  

NASA Astrophysics Data System (ADS)

Chrysaora cf. caliparea, one of the most abundant medusae species in India, seems to be an important predator in the coastal waters of Bay of Bengal. The ability of Chrysaora cf. caliparea to feed at maximum rate in high prey concentrations implies that this jellyfish can efficiently exploit dense prey patches, at least for a short period. This study presents preliminary information regarding digestion and feeding rate upon copepods in a warm water environment. The ingestion rate of the average-sized medusae Chrysaora cf. caliparea is well balanced in nature, which in turn implies that this jellyfish is tuned for optimal utilization of available prey resources. Comparison with earlier research indicates that prey escape speed is one important factor governing which prey will be captured. A full understanding of predation mechanics awaits further investigation of both predator and prey behavior. However, because of the scarcity of long-term quantitative population data most insights have to be made indirectly. Nevertheless, low abundance of Chrysaora cf. caliparea in the water column during summer (May 2007) and the overall annual abundance seem not to considerably affect the zooplankton population, especially copepods. The present work contributes to the knowledge of prey-predator relationship of the forgotten fauna in Indian waters, which is especially crucial for understanding the process of ecological recovery of coastal water environment.

Kanagaraj, Govindan; Ezhilarasan, Pazhaniyappan; Sampathkumar, Pitchai; Morandini, André C.; Sivakumar, Velayudhan Pillai

2011-03-01

371

Development of a quantitative real-time PCR for the detection of Tenacibaculum maritimum and its application to field samples.  

PubMed

The development and the application of a quantitative real-time PCR for the detection of Tenacibaculum maritimum are described. A set of primers and probe was designed to amplify a 155-bp fragment specific to the T. maritimum 16S rRNA gene. The test was shown to be very sensitive, able to detect as little as 4.8 DNA copies number ?L(-1) . In addition, the assay was found to have a high degree of repeatability and reproducibility, with a linear dynamic range (R(2) ?=?0.999) extending over 6 log(10) dilutions and a high efficiency (100%). The assay was applied to DNA samples extracted from 48 formalin-fixed paraffin-embedded (FFPE) Atlantic salmon, Salmo salar, gill tissues showing varying degrees of gill pathology (scored 0-3) and from 26 jellyfish samples belonging to the species Phialella quadrata and Muggiaea atlantica. For each sample, the bacterial load was normalised against the level of the salmonid elongation factor alpha 1 (ELF) detected by a second real-time PCR using previously published primers and probe. Tenacibaculum maritimum DNA was detected in 89% of the blocks with no signs of gill disease as well as in 95% of the blocks with mild-to-severe gill pathology. Association between bacterial load and gill pathology severity was investigated. T. maritimum DNA was detected at low level in four of the 26 jellyfish tested. PMID:22724390

Fringuelli, E; Savage, P D; Gordon, A; Baxter, E J; Rodger, H D; Graham, D A

2012-06-21

372

[Research advances in the effects of environmental factors on the growth and development of Aurelia spp].  

PubMed

Aurelia spp. is a cosmopolitan coastal species, and also, one dominant species of large jellyfish in the coastal waters of China. In recent years, Aurelia spp. bloom events occur frequently in the world, causing severe damage to marine ecosystems, coastal economy, and society development. Aurelia spp. has a complicated life history comprising a benthic asexually-reproducing polyp generation and a sexually-reproducing medusa generation, and various vegetative reproduction (budding, strobilation, and podocyst production) and sexual reproduction. Surrounding physical and biological factors affect each growth stage of Aurelia spp., especially the juvenile stage of planktonic-benthic life cycle, which has major effect on the population dynamics of Aurelia spp. This paper reviewed the research advances in the effects of environmental factors on Aurelia spp. at its different growth and development stages, and discussed some problems worthy of further study, aimed to provide useful reference for the research of the key factors controlling the jellyfish blooms in coastal waters of China. PMID:23431810

Wang, Jian-Yan; Yu, Zhi-Gang; Zhen, Yu; Mi, Tie-Zhu; Yao, Qing-Zhen; Wang, Guo-Shan

2012-11-01

373

High-molecular weight protein toxins of marine invertebrates and their elaborate modes of action.  

PubMed

High-molecular weight protein toxins significantly contribute to envenomations by certain marine invertebrates, e.g., jellyfish and fire corals. Toxic proteins frequently evolved from enzymes meant to be employed primarily for digestive purposes. The cellular intermediates produced by such enzymatic activity, e.g., reactive oxygen species or lysophospholipids, rapidly and effectively mediate cell death by disrupting cellular integrity. Membrane integrity may also be disrupted by pore-forming toxins that do not exert inherent enzymatic activity. When targeted to specific pharmacologically relevant sites in tissues or cells of the natural enemy or prey, toxic enzymes or pore-forming toxins even may provoke fast and severe systemic reactions. Since toxin-encoding genes constitute "hot spots" of molecular evolution, continuous variation and acquirement of new pharmacological properties are guaranteed. This also makes individual properties and specificities of complex proteinaceous venoms highly diverse and inconstant. In the present chapter we portray high-molecular weight constituents of venoms present in box jellyfish, sea anemones, sea hares, fire corals and the crown-of-thorns starfish. The focus lies on the latest achievements in the attempt to elucidate their molecular modes of action. PMID:20358685

Butzke, Daniel; Luch, Andreas

2010-01-01

374

Dietary exposure to aluminium of the Hong Kong population.  

PubMed

A total of 256 individual food samples were collected in Hong Kong for aluminium testing. Most of food samples were analysed in ready-to-eat form. High aluminium levels were found in steamed bread/bun/cake (mean: 100-320 mg kg(-1)), some bakery products such as muffin, pancake/waffle, coconut tart and cake (mean: 250, 160, 120 and 91 mg kg(-1), respectively), and jellyfish (ready-to-eat form) (mean: 1200 mg kg(-1)). The results demonstrated that aluminium-containing food additives have been widely used in these food products. The average dietary exposure to aluminium for a 60 kg adult was estimated to be 0.60 mg kg(-1) bw week(-1), which amounted to 60% of the new PTWI established by JECFA. The main dietary source was "steamed bread/bun/cake", which contributed to 60% of the total exposure, followed by "bakery products" and "jellyfish", which contributed to 23 and 10% of the total exposure, respectively. However, the estimation did not include the intake of aluminium from natural food sources, food contact materials or other sources (e.g. drinking water). Although the results indicated that aluminium it is unlikely to cause adverse health effect for the general population, the risk to some populations who regularly consume foods with aluminium-containing food additives cannot be ruled out. PMID:20234962

Wong, Waiky W K; Chung, Stephen W C; Kwong, K P; Yin Ho, Yuk; Xiao, Ying

2010-04-01

375

Simulation of optically conditioned retention and mass occurrences of Periphylla periphylla.  

PubMed

Jellyfish blooms are of increasing concern in many parts of the world, and in Norwegian fjords an apparent increase in mass occurrences of the deep water jellyfish Periphylla periphylla has attracted attention. Here we investigate the hypothesis that changes in the water column light attenuation might cause local retention and thereby facilitate mass occurrences. We use a previously tested individual-based model of light-mediated vertical migration in P. periphylla to simulate how retention is affected by changes in light attenuation. Our results suggest that light attenuation, in combination with advection, has a two-sided effect on retention and that three fjord categories can be defined. In category 1, increased light attenuation turns fjords into dark "deep-sea" environments which increase the habitat and retention of P. periphylla. In category 2, an optimal light attenuation facilitates the maximum retention and likelihood for mass occurrences. In category 3, further increase in light attenuation, however, shoals the habitat so that individuals are increasingly exposed to advection and this results in loss of individuals and decreased retention. This classification requires accurate determinations of the organism's light preference, the water column light attenuation and topographical characteristics affecting advection. PMID:20454515

Dupont, Nicolas; Aksnes, Dag L

2010-02-19

376

Irukandji syndrome: a widely misunderstood and poorly researched tropical marine envenoming.  

PubMed

Irukandji syndrome is a poorly defined set of symptoms that occur after envenoming by certain species of jellyfish, primarily cubozoans or 'box jellyfish'. Envenomed victims can show symptoms ranging from headaches, severe pain, nausea and vomiting to pulmonary oedema, cardiac failure and severe hypertension resulting in death. Historically, this syndrome appears to have been misdiagnosed and reported cases are undoubtedly a significant underestimation of the prevalence of this syndrome. The variation in symptoms has resulted in a myriad of treatments though none has been established as definitive. Effective pain relief with opioids is the most immediate priority. Although the annual numbers of envenomations are generally low, the associated financial costs of this envenomation may be comparatively high, with suggestions that it could run to millions of dollars per season in northern Australia alone. The syndrome has been well documented from many areas along the east coast of northern Australia, leading to the belief that it is an Australian oddity. However, with an increase in medical knowledge and improved diagnosis of the condition, it appears that envenomations causing Irukandji syndrome are an increasing marine problem worldwide. PMID:23258458

Carrette, Teresa J; Underwood, Avril H; Seymour, Jamie E

2012-12-01

377

Epidemiology of the Cnidarian Physalia physalis stings attended at a health care center in beaches of Adicora, Venezuela.  

PubMed

Stings caused by jellyfish and jellyfish-like colonies are common all around the world, with serious manifestations and occasional deaths reported in some countries. Between December 2006 and 2007, epidemiological, clinical and treatment aspects of stings caused by the Portuguese man-of-war (Physalia physalis) in 59 patients consulting the ambulatory emergency in Adicora, Falcon State, Venezuela, were studied. Most of the stings occurred in males (59%) preschool and school-aged children (49%), visitors from other areas of the country (92%) during holidays when bathing or diving at the beach (97%). Injuries presented linear erythematous plaques at the point of contact with the animal, located in several anatomical sites. Most clinical manifestations observed were: intense burning pain, urticaria, erythema and inflammation (100%), as well dyspnea with laryngeal edema and fever (19%). Patients were treated with topical drugs, including antihistamine and antipyretic drugs, but also with systemic hydrocortisone. P. physalis stings in Adicora appeared to have a seasonal pattern, with systemic complications potentially life-threatening. Thus, epidemiological surveillance program is recommended, particularly in travelers. PMID:23067562

Cazorla-Perfetti, Dalmiro J; Loyo, Jesus; Lugo, Lusneida; Acosta, María E; Morales, Pedro; Haddad, Vidal; Rodriguez-Morales, Alfonso J

2012-10-13

378

Simulation of optically conditioned retention and mass occurrences of Periphylla periphylla  

PubMed Central

Jellyfish blooms are of increasing concern in many parts of the world, and in Norwegian fjords an apparent increase in mass occurrences of the deep water jellyfish Periphylla periphylla has attracted attention. Here we investigate the hypothesis that changes in the water column light attenuation might cause local retention and thereby facilitate mass occurrences. We use a previously tested individual-based model of light-mediated vertical migration in P. periphylla to simulate how retention is affected by changes in light attenuation. Our results suggest that light attenuation, in combination with advection, has a two-sided effect on retention and that three fjord categories can be defined. In category 1, increased light attenuation turns fjords into dark “deep-sea” environments which increase the habitat and retention of P. periphylla. In category 2, an optimal light attenuation facilitates the maximum retention and likelihood for mass occurrences. In category 3, further increase in light attenuation, however, shoals the habitat so that individuals are increasingly exposed to advection and this results in loss of individuals and decreased retention. This classification requires accurate determinations of the organism's light preference, the water column light attenuation and topographical characteristics affecting advection.

Dupont, Nicolas; Aksnes, Dag L.

2010-01-01

379

Stimulated bacterioplankton growth and selection for certain bacterial taxa in the vicinity of the ctenophore Mnemiopsis leidyi  

PubMed Central

Episodic blooms of voracious gelatinous zooplankton, such as the ctenophore Mnemiopsis leidyi, affect pools of inorganic nutrients and dissolved organic carbon by intensive grazing activities and mucus release. This will potentially influence bacterioplankton activity and community composition, at least at local scales; however, available studies on this are scarce. In the present study we examined effects of M. leidyi on bacterioplankton growth and composition in incubation experiments. Moreover, we examined community composition of bacteria associated with the surface and gut of M. leidyi. High release of ammonium and high bacterial growth was observed in the treatments with M. leidyi relative to controls. Deep 454 pyrosequencing of 16 S rRNA genes showed specific bacterial communities in treatments with M. leidyi as well as specific communities associated with M. leidyi tissue and gut. In particular, members of Flavobacteriaceae were associated with M. leidyi. Our study shows that M. leidyi influences bacterioplankton activity and community composition in the vicinity of the jellyfish. In particular during temporary aggregations of jellyfish, these local zones of high bacterial growth may contribute significantly to the spatial heterogeneity of bacterioplankton activity and community composition in the sea.

Dinasquet, Julie; Granhag, Lena; Riemann, Lasse

2012-01-01

380

Studies on the orthogonal assembly of ?-cyclodextrin-poly (?-caprolactone) and ferrocene-poly (ethylene oxide).  

PubMed

A biodegradable multi-arm polymer ?-cyclodextrin-poly (?-caprolactone) (CD-PCL) with a ``jellyfish-like'' structure was obtained, in which flexible and hydrophobic PCL arms were selectively grafted to the wide side of the hydrophilic torus-shaped ?-CD. The amphiphilic "jellyfish-like'' polymer with a hollow cavity and hydrophobic tails could orthogonally self-assemble into a new amphiphilic supramolecular copolymer CD-PCL/FcPEG with poly (ethylene oxide) end-decorated by ferrocene (FcPEG) in aqueous solution based on terminal hydrophobic interactions. The chemical structures of CD-PCL and CD-PCL/FcPEG were characterized by IR, NMR and UV and their self-assembled structures in water were investigated by transmission electron microscopy (TEM) and dynamic light scattering (DLS). CD-PCL alone self-assembled into nano vesicles in water, while CD-PCL/FcPEG into nanospheres. The supramolecular nanospheres were further investigated by cyclic voltammogram. The results indicated that the ferrocenyl groups which were embedded into the hydrophobic core of the supramolecular nanospheres could not transmit electrons or carry out electrochemical oxidation and reduction reaction. PMID:23399190

Ming-Wei, Jiang; Cheng-Gong, Guo; Liang, Wang; Ya-Kun, Li; Cai-Qi, Wang

2012-11-10

381

Preparation of nitrogen-doped graphene sheets by a combined chemical and hydrothermal reduction of graphene oxide.  

PubMed

Nitrogen-doped graphene sheets were prepared through a hydrothermal reduction of colloidal dispersions of graphite oxide in the presence of hydrazine and ammonia at pH of 10. The effect of hydrothermal temperature on the structure, morphology, and surface chemistry of as-prepared graphene sheets were investigated though XRD, N(2) adsorption, solid-state (13)C NMR, SEM, TEM, and XPS characterizations. Oxygen reduction and nitrogen doping were achieved simultaneously under the hydrothermal reaction. Up to 5% nitrogen-doped graphene sheets with slightly wrinkled and folded feature were obtained at the relative low hydrothermal temperature. With the increase of hydrothermal temperature, the nitrogen content decreased slightly and more pyridinic N incorporated into the graphene network. Meanwhile, a jellyfish-like graphene structure was formed by self-organization of graphene sheets at the hydrothermal temperature of 160 °C. Further increase of the temperature to 200 °C, graphene sheets could self-aggregate into agglomerate particles but still contained doping level of 4 wt % N. The unique hydrothermal environment should play an important role in the nitrogen doping and the jellyfish-like graphene formation. This simple hydrothermal method could provide the synthesis of nitrogen-doped graphene sheets in large scale for various practical applications. PMID:20863088

Long, Donghui; Li, Wei; Ling, Licheng; Miyawaki, Jin; Mochida, Isao; Yoon, Seong-Ho

2010-10-19

382

Recovery of fish stocks in the Seto Inland Sea.  

PubMed

The total amount of fisheries' yield in the Seto Inland Sea in 1999 was 571,000 MT, consisting of 256,000 MT by fishing and 315,000 MT from aquaculture. About 40,000 people engaged in the fishing and aquaculture industries, earned 129 billion yen (1100 million US$) by fishing and 89 billion yen (770 million $US) by aquaculture. The averaged annual catch for the Seto Inland Sea by fishing was 13 MT/km(2). Division into time periods in terms of eutrophication levels can be made: before 1960 when red sea bream were abundant with ecological divergence (before eutrophication), from 1960 to 1990 when the biomass of anchovy was large (during eutrophication), and after 1990 when the jellyfishes were abundant (excessive eutrophication or high N:P ratio). The fish production will decrease in the sea of jellyfishes. Actually, the amount of catch was 462,000 MT in 1982 which decreased 265,000 MT in 1993, corresponding to 43% in twelve years, then keeping the same level. A big reduction was seen in the catches of the spotlined sardine, anchovy, Spanish mackerel, tiger puffer, short-necked clam, sea cucumber and others. The tiger puffer and Spanish mackerel were abundant as predators in the sea of anchovy. The biomass of anchovy was at its maximum in 1986 and decreased to less than one third in 1996. The stocks of tiger puffer and Spanish mackerel greatly decreased because of the higher fishing pressure compared to the anchovy stock. The fishing power of individual fisheries targeting on the tiger puffer and Spanish mackerel increased substantially when fishing vessel and fishing gear improved, resulting in an excessive fishing effort. A large quantity of small immature fishes is usually caught in the Seto Inland Sea, resulting in growth and/or recruitment overfishing for many species. Hence, it is necessary to promote management of the fisheries so as not to reduce the fish stocks, and to allow the Seto Inland Sea to return from being a sea of jellyfishes to a sea of anchovy, with decreased eutrophication levels. PMID:12787608

Nagai, T

2003-01-01

383

Amazing Jellies  

NSDL National Science Digital Library

Learners can select from three online interactives to learn more about sea creatures known as jellies (often mistakenly known as jellyfish). In "Blobs of Goo", learners explore the question "What is a Jelly?" and guess the features of jelly anatomy. In "Life Cycles", learners play a game and earn points to complete the life cycles of moon jellies. Finally, in "JellyTown", learners play a game in order to maintain the ecological balance in the ocean and/or town and observe the effects of pollution and ocean warming on jellies, their predators and prey. There are three game modes for various ages. Although this site supports the learning associated with an aquarium exhibit, a visit is not necessary to participate in these activities.

Aquarium, New E.; University, Northeastern

2011-01-01

384

Genetically modified plants for tactical systems applications  

NASA Astrophysics Data System (ADS)

Plants are ubiquitous in the environment and have the ability to respond to their environment physiologically and through altered gene expression profiles (they cannot walk away). In addition, plant genetic transformation techniques and genomic information in plants are becoming increasingly advanced. We have been performing research to express the jellyfish green fluorescent protein (GFP) in plants. GFP emits green light when excited by blue or UV light. In addition, my group and collaborators have developed methods to detect GFP in plants by contact instruments and at a standoff. There are several tactical uses for this technology. Some obvious applications are using plants as sentinels for detecting biological and chemical warfare agents or their derivatives from a remote platform, as well as detecting explosives. Another tactical application is covert monitoring using individual plants. Different methods to detect GFP in transgenic plants will be discussed.

Stewart, C. Neal, Jr.

2002-08-01

385

Animal-related fatalities--part II: characteristic autopsy findings and variable causes of death associated with envenomation, poisoning, anaphylaxis, asphyxiation, and sepsis.  

PubMed

In addition to blunt and sharp trauma, animal-related fatalities may result from envenomation, poisoning, anaphylaxis, asphyxiation, and sepsis. Although the majority of envenomation deaths are caused by hornets, bees, and wasps, the mechanism of death is most often anaphylaxis. Envenomation resulting from the injection of a poison or toxin into a victim occurs with snakes, spiders, and scorpions on land. Marine animal envenomation may result from stings and bites from jellyfish, octopus, stonefish, cone fish, stingrays, and sea snakes. At autopsy, the findings may be extremely subtle, and so a history of exposure is required. Poisoning may also occur from ingesting certain fish, with three main forms of neurotoxin poisoning involving ciguatera, tetrodotoxin ingestion, and paralytic shellfish poisoning. Asphyxiation may follow upper airway occlusion or neck/chest compression by animals, and sepsis may follow bites. Autopsy analysis of cases requires extensive toxinological, toxicological, and biochemical analyses of body fluids. PMID:21981407

Bury, Danielle; Langlois, Neil; Byard, Roger W

2011-10-07

386

Pathophysiology of the spreading of complex regional pain syndrome revisited: a case report.  

PubMed

Objective:? To determine if there is a relationship in our patient developing complex regional pain syndrome from a jellyfish and its subsequent spread to the contralateral side. Methods:? Data bases were searched using PubMed and Ovid. Keywords searched include "complex regional pain syndrome,"jelly fish," and "pathophysiology." Results:? This patient was successfully treated with a spinal cord stimulator implantation with bilateral lead placement at thoracic spine (T9) stimulating her lower extremities in addition to the leads that had already been placed in her cervical spine for her upper extremities. Conclusion:? Definite knowledge of the pathophysiology of complex regional pain syndrome would allow better identification of risk factors for the development of this condition after trauma. This patient is at higher risk of developing complex regional pain syndrome and should avoid surgeries (such as knee and wrist surgeries) and high risk physical activities. PMID:21854496

Azari, Pari; Lu, Yan; Clarke, Colin F M; Collins, Timothy; Briones, Dean; Huh, Billy

2011-08-19

387

Improved silencing suppression and enhanced heterologous protein expression are achieved using an engineered viral helper component proteinase.  

PubMed

RNA silencing limits transient expression of heterologous proteins in plants. Co-expression of viral silencing suppressor proteins can increase and prolong protein expression, but highly efficient silencing suppressors may stress plant tissue and be detrimental to protein yields. Little is known whether silencing suppression could be improved without harm to plant tissues. This study reports development of enhanced silencing suppressors by engineering the helper component proteinase (HCpro) of Potato virus A (PVA). Mutations were introduced to a short region of HCpro (positions 330-335 in PVA HCpro), which is hypervariable among potyviruses. Three out of the four HCpro mutants suppressed RNA silencing more efficiently and sustained expression of co-expressed jellyfish green fluorescent protein for a longer time than wild-type HCpro in agroinfiltrated leaves of Nicotiana benthamiana. Leaf tissues remained healthy-looking without any visible signs of stress. PMID:23933077

Haikonen, T; Rajamäki, M-L; Valkonen, J P T

2013-08-06

388

Fully resolved simulation of self-propulsion of aquatic organisms  

NASA Astrophysics Data System (ADS)

We present a computational approach for fully resolved simulation of self-propulsion of organisms through a fluid. Our implicit algorithm solves for the translational and rotational motion of the organism for prescribed deformation kinematics. In addition, the solution for the surrounding flow field is also obtained. The approach is easy to apply to the body forms of a variety of organisms. Our final goal is to use this computational tool to help in understanding the mechanisms of movement and its control in aquatic animals. In this abstract we present validation of this method for different organisms. To validate the method with respect to analytical solutions, we consider two cases: 1) a flagellum which propagates plane waves, and 2) a flagellum that propagates helical waves. To validate the method with respect to empirical measurements we consider data from two organisms: 1) jellyfish (data from John Dabiri at Caltech), and 2) zebrafish (data from Melina Hale at The University of Chicago).

Curet, Oscar M.; Alali, Ibrahim; Patankar, Neelesh A.; Maciver, Malcolm A.

2008-11-01

389

Rapid evolutionary radiation of marine zooplankton in peripheral environments  

PubMed Central

Populations of jellyfish, Mastigias sp., landlocked in tropical marine lakes during the Holocene, show extreme genetic isolation (0.74 ? ?ST ? 1.00), founder effects (genetic diversity: 0.000 ? ? ? 0.001), rapid morphological evolution, and behavioral adaptation. These results demonstrate incipient speciation in what we propose may be modern analogues of Plio-Pleistocene populations isolated in ocean basins by glacially lowered sea level and counterparts to modern marine populations isolated on archipelagos and other distant shores. Geographic isolation in novel environments, even if geologically brief, may contribute much to marine biodiversity because evolutionary rates in marine plankton can rival the most rapid speciation seen for limnetic species, such as cichlids and sticklebacks. Marine lakes present situations rare in their clarity for studying evolution in marine taxa.

Dawson, Michael N; Hamner, William M.

2005-01-01

390

Assessment of space environmental factors by cytotoxicity bioassays  

NASA Astrophysics Data System (ADS)

Cellular bioassays for detection of cyto- and genotoxicity are useful in the risk assessment of space environmental factors. Such bioassay systems have the potential complement the physical detector systems used in space, insofar as they yield intrinsically biologically weighted measures of cellular responses. The experiment Cellular Responses to Radiation in Space (CERASP) has been selected by NASA/ESA to be performed on the International Space Station. It will supply basic information on the cellular response to radiation applied in microgravity. One of the biological endpoints under investigation will be survival reflected by radiation-dependent reduction of constitutive expression of the enhanced variant of green fluorescent protein (EGFP), originally isolated from the bioluminescent jellyfish Aequorea victoria. In this ground based study, the usefulness of this approach in comparison to standard techniques (colony forming ability test, MTT test) is shown.

Hellweg, Christine E.; Arenz, Andrea; Baumstark-Khan, Christa

2007-02-01

391

Fabrication and observation of nanowire-assemblages of Si-Ge  

NASA Astrophysics Data System (ADS)

A few of the interesting structures made by the assemblage of Si-Ge nanowires fabricated by the floating-zone melting-vapor method have been observed. They reveal shapes that are similar to coral, jellyfish and sea anemones. The pre-sintered substrate bar has some large crystalline particles (1-15 ?m), which produce sites that are energetically predisposed to nucleation. The peculiar structures created by the assemblage of Si-Ge nanowires form on favored nucleation sites that consist of numerous bundles of nanowires with diameters of 20-50 nm. The periodic variation in the diameter of the bundles of nanowires is a common feature of these structures. In addition, a growth mechanism assisted by the coexistence of Ge and Si-Ge oxides is suggested. The growth process of these assemblages opens up new possibilities for the study of the growth mechanism of Si-Ge nanowires.

Hu, Q.; Araki, H.; Suzuki, H.; Ishikawa, N.; Yang, W.; Noda, T.

392

Exceptionally preserved Late Ordovician biotas from Manitoba, Canada  

NASA Astrophysics Data System (ADS)

There are few body fossil biotas known from early Paleozoic accretionary shorelines, and very few examples of Ordovician soft-bodied assemblages. This study documents two recently discovered biotas from separate sedimentary basins in Manitoba, Canada, that provide unique information about tropical shoreline communities shortly before the Late Ordovician extinction event. Each site represents a distinct depositional environment, but they share biotic elements, including eurypterids, xiphosurids, and large problematic tubes. The William Lake biota, representing more restricted conditions, includes jellyfish that are among the best hydromedusan body fossils known. Rocks at the Airport Cove site, deposited under more open circulation, contain scolecodonts and noncalcified algae. These biotas have some parallels with the recently described Middle Ordovician Winneshiek Lagerstätte, but are also similar to some Late Silurian assemblages. Considered together, early Paleozoic marginal marine deposits are a rich but as yet poorly known source of paleobiodiversity data.

Young, Graham A.; Rudkin, David M.; Dobrzanski, Edward P.; Robson, Sean P.; Nowlan, Godfrey S.

2007-10-01

393

The evolution of lenses.  

PubMed

Structures which bend light and so form images are present in all the major phyla. Lenses with a graded refractive index, and hence reduced spherical aberration, evolved in the vertebrates, arthropods, annelid worms, and several times in the molluscs. Even cubozoan jellyfish have lens eyes. In some vertebrate eyes, multiple focal lengths allow some correction for chromatic aberration. In land vertebrates the cornea took over the main ray-bending task, leaving accommodation as the main function of the lens. The spiders are the only other group to make use of a single cornea as the optical system in their main eyes, and some of these - the salticids - have evolved a remarkable system based on image scanning. Similar scanning arrangements are found in some crustaceans, sea-snails and insect larvae. PMID:23057564

Land, Michael F

2012-11-01

394

Aquatic dermatology: encounters with the denizens of the deep (and not so deep) a review. Part I: the invertebrates.  

PubMed

Aquatic dermatoses encompass a broad spectrum of cutaneous injuries. These injuries may present through contact with invertebrate organisms such as jellyfish, sea urchins, corals, and molluscs. Each organism is equipped with a unique method of causing harm to man, therefore a myriad of presenting signs and symptoms should be recognized in order to initiate treatment. Aquatic injuries are not limited to areas of the world where these species originate. With the advent of rapid world travel and the hobby of home aquariums, dermatologists play a key role in the early diagnosis and treatment of such injuries. The method of injury, including a discussion of organism identification will be presented. Additionally, treatment of injuries caused by aquatic life will follow. PMID:23347300

Ottuso, Patrick

2013-02-01

395

Integrated trend assessment of ecosystem changes in the Limfjord (Denmark): Evidence of a recent regime shift?  

NASA Astrophysics Data System (ADS)

An integrated ecosystem assessment was carried out for the Limfjord over the period from 1984 to 2008 to describe changes in ecosystem structure and potentially important drivers. The Limfjord is a eutrophic transitional Danish fjord system with the main inflow from the North Sea in the west and main outflow to the Kattegat in the east. We showed that from 1990 to 1995, the ecosystem structure shifted from dominance by demersal fish species (eelpout, whiting, flounder, plaice) to that of pelagic fish species (sprat, herring, sticklebacks), small-bodied fish species (black goby, pipefish), jellyfish, common shore crab, starfish and blue mussels. We interpret this change as a regime shift that showed a similar temporal pattern to regime shifts identified in adjacent seas. The observed changes in trophic interactions and food web reorganisation suggested a non-linear regime shift. The analyses further showed the regime shift to be driven by a combination of anthropogenic pressures and possible interplay with climatic disturbance.

Tomczak, Maciej T.; Dinesen, Grete E.; Hoffmann, Erik; Maar, Marie; Støttrup, Josianne G.

2013-01-01

396

Toward an european Med HF-radar coastal monitoring  

NASA Astrophysics Data System (ADS)

The monitoring of coastal areas through HF radar is developping in the european Mediterranean coasts, through national and international projects. Surface current maps may be used for process studies, forecast correction through assimilation, or for practical applications in transport studies (jellyfish, oil-spill, search-and-rescue operations). Results of radar campaigns in the North-western Mediterranean (evidence of mesoscale eddy in the Gulf of Lions and identification of dynamical structures by FSLE in the Ligurian Sea) are shown, as well as techniques for current reconstruction using a single site. A new inter-regional european project started in summer 2010, regrouping 5 countries for an integrated oil-spill coastal awarness network is presented.

Molcard, A.; Fraunie, P.

2010-12-01

397

Angiotensin converting enzyme (ACE) inhibitory, antihypertensive and antihyperlipidaemic activities of protein hydrolysates from Rhopilema esculentum.  

PubMed

Angiotensin-converting enzyme (ACE) inhibitory, antihypertensive and antihyperlipidaemic activities of protein hydrolysates (RPH) from the jellyfish Rhopilema esculentum were investigated. R. esculentum was hydrolysed sequentially with pepsin and papain, and then the hydrolysate was ultrafiltered with a 2000 Da cut-off membrane. It was found that RPH contained high levels of Gly, Glu, Pro, Asp and Ala, having potential ACE inhibitory activity in vitro with an IC(50) of 1.28 mg/ml. It was also found that systolic blood pressure was reduced markedly in spontaneously hypertensive rats after single and chronic oral administration of RPH, indicating that RPH had an antihypertensive effect. In addition, oral administration of RPH decreased total serum cholesterol and triglyceride, and increased high-density lipoprotein cholesterol in rats fed with high-fat diet. These results indicate that RPH may prove to be a promising functional food for the prevention and treatment of hypertension and hyperlipidaemia. PMID:23442666

Liu, Xin; Zhang, Miansong; Zhang, Chao; Liu, Changheng

2012-04-16

398

A study of the possibility of sprites in the atmospheres of other planets  

NASA Astrophysics Data System (ADS)

Sprites are a spectacular type of transient luminous events which occur above thunderstorms immediately after lightning. They have shapes of giant jellyfish, carrots, or columns and last tens of milliseconds. In Earth's atmosphere, sprites mostly emit in red and blue wavelengths from excited N2 and N2 + and span a vertical range between 50 and 90 km above the surface. The emission spectra, morphology, and occurrence heights of sprites reflect the properties of the planetary atmosphere they inhabit and are related to the intensity of the initiating parent lightning. This paper presents results of theoretical calculations of the expected occurrence heights of sprites above lightning discharges in the CO2 atmosphere of Venus, the N2 atmosphere of Titan, and the H2-He atmosphere of Jupiter. The expected emission features are presented, and the potential of detecting sprites in planetary atmospheres by orbiting spacecraft is discussed.

Yair, Yoav; Takahashi, Yukihiro; Yaniv, Roy; Ebert, Ute; Goto, Yukihiro

2009-09-01

399

Is cell death induced by nematocysts extract of medusa pelagia noctiluca related to oxidative stress?  

PubMed

Pelagia noctiluca, a jellyfish widely distributed in the Mediterranean waters, especially in coastal areas of Tunisia, has garnered attention because of its stinging capacity and the resulting public health hazard. Crude extracts of P. noctiluca nematocysts have been tested for their cytotoxicity on Vero cells. Our results clearly showed that nematocysts induced cell mortality in a dose- and time-dependent manner. A cytoprotective effect against cell mortality was obtained when Vero cells were treated with Vitamin E. This process was further confirmed by the generation of reactive oxygen species (ROS) and the induction of Hsp 70 and 27 protein expressions. Thus, our findings suggested that oxidative stress is involved in the toxicity of pelagia nematocysts and may therefore constitute the major mechanism of this medusa nematocysts toxicity. © 2011 Wiley Periodicals, Inc. Environ Toxicol 28: 498-506, 2013. PMID:21809431

Ayed, Yosra; Chayma, Bouaziz; Hayla, Abassi; Abid, Salwa; Bacha, Hassen

2011-08-01

400

Utah's Cambrian Life  

NSDL National Science Digital Library

What was going on in Utah 500 million years ago? Quite a bit, and this website provides an excellent overview of the diverse Cambrian life that flourished in an ancient sea that covered what is now the Beehive State. Interestingly enough, the website was created by the division of invertebrate paleontology at the University of Kansas Natural History Museum, and it includes images of a wide array of fossilized materials from this period of geological history. On the left-hand side of the page, visitors will find four primary sections, including "Localities and Geology" and "Online Fossil Exhibits and Collections". The "Localities and Geology" area is a good place to start as it gives an overview (complete with aerial photographs and maps) of the Cambrian period in Utah. The "Online Fossil Exhibits and Collections" area features fossil representative images from groups like mollusks, algae, jellyfish, and lobopods.

401

The stability of a family of vortex rings  

NASA Astrophysics Data System (ADS)

Jetting swimmers, such as squid or jellyfish, propel themselves by forming axisymmetric vortex rings. In order to evaluate the performance of these swimmers, we must asses the optimality of the vortex wakes they produce, which requires an understanding of their stability. We consider the Norbury family of vorticesootnotetextJ. Norbury, J. Fluid Mech., 57, 417-431, 1973. as a model for the vortex rings produced by jetting swimmers. PozrikidisootnotetextC. Pozrikidis, J. Fluid Mech., 168, 337-367, 1986. has studied the stability of Hill's spherical vortex under axisymmetric prolate and oblate shape perturbations. However, the stability of other members of the Norbury family to axisymmetric perturbations of the type that might occur during the vortex formation process in jetting swimmers is unknown. In order to asses the stability of different members of the family, we introduce physically pertinent shape perturbations and simulate their development in a manner akin to Pozrikidis' analysis.

O'Farrell, Clara; Dabiri, John O.

2010-11-01

402

Bacterial Transformation with Green Fluorescent Protein  

NSDL National Science Digital Library

From the University of California, Davis, Partnership for Plant Genomics Education, this biotechnology laboratory is a five-day activity with bacterial transformations and green fluorescent protein. âÂÂIn this lab activity, students will attempt to cause a wild type strain of E. coli to incorporate and express a plasmid containing a gene that codes for a green fluorescent protein (GFP). The source of the GFP gene is the bioluminescent jellyfish Aequorea victoria. The plasmid also contains an ampicillin-resistance gene.â Several bioethics activities, readings, and diagrams help to illustrate and supplement the experiment. There are safety instructions, objectives, materials, preparation and clean-up notes, procedures, and questions for students to answer. ItâÂÂs a ready-to-use activity for biotechnology or plant genomics classrooms.

2008-12-09

403

A Touch of Class  

NSDL National Science Digital Library

In this online game, learners test their skills of categorization. Sixteen different organisms are given (human, monkey, jellyfish, etc.) and one category (e.g., things that eat fish, birds, things that lay eggs). Learners choose the organisms that fit the category and earn points when they choose correctly, but lose points if they choose something not in the category or miss something in the category. This fun and easy game is useful as introduction or review of the diversity of life. When learners set up a free account at Kinetic City, they can answer bonus questions at the end of the activity as a quick assessment. As a larger assessment, learners can complete the Smart Attack game after they've completed several activities.

Science, American A.

2009-01-01

404

Chesapeake Bay Program: Animals and Plants  

NSDL National Science Digital Library

This site describes the biota of the Chesapeake Bay, including mammals, fish, reptiles, amphibians, and crabs and shellfish. Lower food web organisms described are plankton, benthos, Shipworm, Bristle Worm, Jellyfish, Red Beard Sponge, Sea Squirt, Comb Jellies, and the Ghost Anemone. The description of the flora is confined to bay grasses, which are also known as submerged aquatic vegetation (SAV). Birds described at this site include Bald Eagle, Bufflehead, Osprey, Great Blue Heron, Eastern Screech-Owl, Gulls, Ruddy Duck, Carolina Chickadee, Ruddy Turnstone, and the large group known as waterfowl. The site also includes a special section on invasive species, and provides links to publications, status and trends, and extensive databases that include water quality, living resources, point sources, modeling, and cross-cutting indicators.

405

Structure of a fluorescent protein from Aequorea victoria bearing the obligate-monomer mutation A206K.  

PubMed

The green fluorescent protein (GFP) from the jellyfish Aequoria victoria has been shown to dimerize at high concentrations, which could lead to artefacts in imaging experiments. To ensure a truly monomeric state, an A206K mutation has been introduced into most of its widely used variants, with minimal effect on the spectroscopic properties. Here, the first structure of one of these variants, the cyan fluorescent protein mTurquoise, is presented and compared with that of its dimeric version mTurquoise-K206A. No significant structural change is detected in the chromophore cavity, reinforcing the notion that this mutation is spectroscopically silent and validating that the structural analysis performed on dimeric mutants also applies to monomeric versions. Finally, it is explained why cyan versions of GFP containing the Y66W and N146I mutations do not require the A206K mutation to prevent dimerization at high concentrations. PMID:22869113

von Stetten, David; Noirclerc-Savoye, Marjolaine; Goedhart, Joachim; Gadella, Theodorus W J; Royant, Antoine

2012-07-26

406

Improving propulsive efficiency through passive mechanisms using a Starling vortex generator  

NASA Astrophysics Data System (ADS)

Ruiz et al. (2011) demonstrated that pulsed propulsion with vortex rings, much like those seen in the wake of jellyfish and squid, can greatly enhance the overall efficiency of submersible vehicles. The objective of the present research is to achieve pulsed propulsion passively using a Starling vortex generator which consists of a collapsible tube within an airtight box. Recent work has shown that a Starling vortex generator is able to generate vortex rings, which indicates enhanced propulsion, while requiring less energy to generate pulsatility than the system by Ruiz et al. (2011). Current work is focused on conducting an experimental parameter study to determine an empirical scaling law suitable for design purposes, with the aim to integrate the device into a full-scale unmanned undersea vehicle.

Whittlesey, Robert; Dabiri, John

2011-11-01

407

Aurelia aurita bio-inspired tilt sensor  

NASA Astrophysics Data System (ADS)

The quickly expanding field of mobile robots, unmanned underwater vehicles, and micro-air vehicles urgently needs a cheap and effective means for measuring vehicle inclination. Commonly, tilt or inclination has been mathematically derived from accelerometers; however, there is inherent error in any indirect measurement. This paper reports a bio-inspired tilt sensor that mimics the natural balance organ of jellyfish, called the ‘statocyst’. Biological statocysts from the species Aurelia aurita were characterized by scanning electron microscopy to investigate the morphology and size of the natural sensor. An artificial tilt sensor was then developed by using printed electronics that incorporates a novel voltage divider concept in conjunction with small surface mount devices. This sensor was found to have minimum sensitivity of 4.21° with a standard deviation of 1.77°. These results open the possibility of developing elegant tilt sensor architecture for both air and water based platforms.

Smith, Colin; Villanueva, Alex; Priya, Shashank

2012-10-01

408

Analyzing complex networks from a data analysis viewpoint  

NASA Astrophysics Data System (ADS)

From a data analysis perspective, we propose a method called "node projection" to study the complex networks. The method projects network nodes into a high-dimensional measure space and uses the principal component analysis (PCA) to analyze the produced data cloud. By assigning similar nodes to close positions in the measure space, distinct topological patterns of random, regular, small-world and scale-free networks emerge. From the data analysis view, we also confirm the hierarchical structure and jellyfish model of the Internet Autonomous System fabric. We further use the node projection method to extract network feature based on PCA measurements and use them to quantitatively study similarity among selected networks. Similar networks are clustered together. The node projection method can be developed into a universal framework to discover network structural patterns on diverse scales.

Li, W.; Yang, J.-Y.; Hadden, W.-C.

2009-12-01

409

Dynamics and self-propulsion of a spherical body shedding coaxial vortex rings in an ideal fluid  

NASA Astrophysics Data System (ADS)

We describe a model for the dynamic interaction of a sphere with uniform density and a system of coaxial circular vortex rings in an ideal fluid of equal density. At regular intervals in time, a constraint is imposed that requires the velocity of the fluid relative to the sphere to have no component transverse to a particular circular contour on the sphere. In order to enforce this constraint, new vortex rings are introduced in a manner that conserves the total momentum in the system. This models the shedding of rings from a sharp physical ridge on the sphere coincident with the circular contour. If the position of the contour is fixed on the sphere, vortex shedding is a source of drag. If the position of the contour varies periodically, propulsive rings may be shed in a manner that mimics the locomotion of certain jellyfish. We present simulations representing both cases.

Tallapragada, Phanindra; Kelly, Scott David

2013-01-01

410

Man-induced hydrological changes, metazooplankton communities and invasive species in the Berre Lagoon (Mediterranean Sea, France).  

PubMed

The Berre Lagoon has been under strong anthropogenic pressure since the early 1950s. The opening of the hydroelectric EDF power plant in 1966 led to large salinity drops. The zooplankton community was mainly composed of two common brackish species: Acartia tonsa and Brachionus plicatilis. Since 2006, European litigation has strongly constrained the input of freshwater, maintaining the salinity above 15. A study was performed between 2008 and 2010 to evaluate how these modifications have impacted the zooplankton community. Our results show that the community is more diverse and contains several coastal marine species (i.e., Centropages typicus, Paracalanus parvus and Acartia clausi). A. tonsa is still present but is less abundant, whereas B. plicatilis has completely disappeared. Strong predatory marine species, such as chaetognaths, the large conspicuous autochtonous jellyfish Aurelia aurita and the invasive ctenophore Mnemiopsis leidyi, are now very common as either seasonal or permanent features of the lagoon. PMID:22776776

Delpy, Floriane; Pagano, Marc; Blanchot, Jean; Carlotti, François; Thibault-Botha, Delphine

2012-07-07

411

A Darwinian mechanism for biogenic ocean mixing  

NASA Astrophysics Data System (ADS)

Recent observations of biogenic turbulence in the ocean have led to conflicting ideas regarding the contribution of animal swimming to ocean mixing. Previous measurements indicate elevated turbulent dissipation in the vicinity of large populations of planktonic animals swimming in concert. However, elevated turbulent dissipation is by itself insufficient proof of substantial biogenic mixing. We conducted field measurements of mixing efficiency by individual Mastigias sp. (a Palauan jellyfish) using a self-contained underwater velocimetry apparatus. These measurements revealed another mechanism that contributes to animal mixing besides wake turbulence. This mechanism was first described by Sir Charles Galton Darwin and is in fact the dominant mechanism of mixing by swimming animals. The efficiency of Darwin's mechanism (or drift) is dependent on animal shape rather than fluid length scale and, unlike turbulent wake mixing, is enhanced by the fluid viscosity. Therefore, it provides a means of biogenic mixing that can be equally effective in small plankton and large mammals.

Katija, Kakani; Dabiri, John

2009-11-01

412

Do small swimmers mix the ocean?  

NASA Astrophysics Data System (ADS)

In this communication we address some hydrodynamic aspects of recently proposed drift mechanism of biogenic mixing in the ocean [K. Katija and J. O. Dabiri, Nature (London) 460, 624 (2009)10.1038/nature08207]. The relevance of the locomotion gait at various spatial scales with respect to the drift is discussed. A hydrodynamic scenario of the drift based on unsteady inertial propulsion, typical for most small marine organisms, is proposed. We estimate its effectiveness by taking into account interaction of a swimmer with the turbulent marine environment. Simple scaling arguments are derived to estimate the comparative role of drift-powered mixing with respect to the turbulence. The analysis indicates substantial biomixing effected by relatively small but numerous drifters, such as krill or jellyfish.

Leshansky, A. M.; Pismen, L. M.

2010-08-01

413

Antimicrobial Activity of Defensins and Defensin-Like Peptides with Special Emphasis on those from Fungi and Invertebrate Animals.  

PubMed

Living organisms are in perpetual contact with pathogenic microbes, and in encounter with parasites and predators. In order to protect themselves, they produce a variety of antimicrobial proteins and peptides. One family of such protective or defensive proteins is known as defensins, characterized by a cationic character, a low molecular mass, and an abundance of cysteine residues. Defensins from mammals and plants have been succinctly reviewed by a number of experts in this ever-growing field. This review encompasses the defensin plectasin from the saprophytic fungus Pseudoplectania nigrella as well as defensins and defensin-like peptides from invertebrate animals such as jellyfish, sponges, nematodes, crustaceans, arachnids, insects, bivalves, snails, and sea urchins. Big defensins from mollusks are mentioned together with amphioxus big defensin. The structures and activities of these defense proteins are discussed. PMID:23968349

Ng, Tzi Bun; Cheung, Randy Chi Fai; Wong, Jack Ho; Ye, Xiu Juan

2013-09-01

414

Science 360  

NSDL National Science Digital Library

With a mix of interactive features, social media, and other bells and whistles, the Science 360 Knowledge Network "immerses visitors in the latest wonders of science, engineering, technology and math." The Network website is maintained by the National Science Foundation, and it draws on work by the Foundation and other institutions around the world. On the homepage, visitors are presented with a scrolling six by three matrix of items that cover everything from the science of football kinematics, the biology of jellyfish, and the search for extra-terrestrial life. Visitors can browse the "Topics" area at their leisure, or also play the "Featured Videos". Also, visitors can submit their own content for potential inclusion, and also share information with others via Facebook, Twitter, MySpace, and so on.

415

Fluorescence imaging in the last two decades.  

PubMed

In commemoration of the 20th anniversary of the molecular cloning of the gene for the green fluorescent protein from the jellyfish Aequorea victoria, I would like to reflect on the development of new fluorescence imaging technology in the last two decades. As this technology has become increasingly diversified, it has become more and more of a challenge to come up with a comprehensive and exhaustive review of it. Here I will focus on optogenetics and large-scale, three-dimensional reconstruction. Those two technological innovations have been achieved in the neuroscience community owing to the combined efforts of molecular biologists and light microscopists. In addition, modern fluorescence imaging has indeed improved our understanding of the spatiotemporal regulation of fundamental biological functions at cellular level. As an example, I will introduce some findings we made regarding the movement of biomolecules across the nuclear membrane. The above-mentioned imaging approaches are possible today but were impossible two decades ago. PMID:23393311

Miyawaki, Atsushi

2013-02-07

416

Impact of secondary hard substrate on the distribution and abundance of Aurelia aurita in the western Baltic Sea.  

PubMed

This study assessed the impact of secondary hard substrate, as being introduced into marine ecosystems by the establishment of wind farm pillars, on the occurrence and distribution of the moon jelly Aurelia aurita in the southwestern Baltic Sea. A two-year data sampling was conducted with removable settlement plates to assess the distribution and population development of the scyphozoan polyps. The data collected from these samples were used to set up a model with Lagrangian particle technique. The results confirm that anthropogenic created hard substrate (e.g. offshore wind farms) has the potential to increase the abundance of the A. aurita population. The distribution of wind farm borne jellyfish along Danish, German and Polish coasts indicates conflicts with further sectors, mainly energy and tourism. PMID:23987093

Janßen, H; Augustin, C B; Hinrichsen, H H; Kube, S

2013-08-27

417

Venom evolution through gene duplications.  

PubMed

Venoms contain highly complex mixtures that typically include hundreds of different components and have evolved independently in a diverse range of animals including platypuses, shrews, snakes, lizards, fishes, echinoderms, spiders, wasps, centipedes, sea snails, cephalopods, jellyfish and sea anemones. Many venom genes evolved through gene duplication. Gene duplication occurs in all domains of life and provides the raw substrate from which novel function arise. In this review, we focus on the role that gene duplication has played in the origin and diversification of venom genes. We outline the selective advantages of venom gene duplicates and the role that selection has played in the retention of these duplicates. We use toxin gene intermediates to help trace the evolution of toxin innovation. We also focus on other genomic processes, such as exon and domain duplications, in venom evolution. Finally, we conclude by focusing on the use of high throughput sequencing technology in understanding venom evolution. PMID:22285376

Wong, Emily S W; Belov, Katherine

2012-01-18

418

A genomic view of 500 million years of cnidarian evolution  

PubMed Central

Cnidarians (corals, anemones, jellyfish, and hydras) are a diverse group of animals of interest to evolutionary biologists, ecologists, and developmental biologists. With the publication of the genome sequences of Hydra and Nematostella, whose last common ancestor was the stem cnidarian, we are beginning to see the genomic underpinnings of cnidarian biology. Cnidarians are known for the remarkable plasticity of their morphology and life cycles. This plasticity is reflected in the Hydra and Nematostella genomes, which differ to an exceptional degree in size, base composition, transposable element content, and gene conservation. We now know what cnidarian genomes are capable of doing given 500 million years; the next challenge is to understand how this genomic history has led to the striking diversity we see in cnidarians.

Steele, Robert E.; David, Charles N.; Technau, Ulrich

2010-01-01

419

New Unstable Variants of Green Fluorescent Protein for Studies of Transient Gene Expression in Bacteria  

PubMed Central

Use of the green fluorescent protein (Gfp) from the jellyfish Aequorea victoria is a powerful method for nondestructive in situ monitoring, since expression of green fluorescence does not require any substrate addition. To expand the use of Gfp as a reporter protein, new variants have been constructed by the addition of short peptide sequences to the C-terminal end of intact Gfp. This rendered the Gfp susceptible to the action of indigenous housekeeping proteases, resulting in protein variants with half-lives ranging from 40 min to a few hours when synthesized in Escherichia coli and Pseudomonas putida. The new Gfp variants should be useful for in situ studies of temporal gene expression.

Andersen, Jens Bo; Sternberg, Claus; Poulsen, Lars Kongsbak; Bj?rn, Sara Petersen; Givskov, Michael; Molin, S?ren

1998-01-01

420

A new way to rapidly create functional, fluorescent fusion proteins: random insertion of GFP with an in vitro transposition reaction  

PubMed Central

Background The jellyfish green fluorescent protein (GFP) can be inserted into the middle of another protein to produce a functional, fluorescent fusion protein. Finding permissive sites for insertion, however, can be difficult. Here we describe a transposon-based approach for rapidly creating libraries of GFP fusion proteins. Results We tested our approach on the glutamate receptor subunit, GluR1, and the G protein subunit, ?s. All of the in-frame GFP insertions produced a fluorescent protein, consistent with the idea that GFP will fold and form a fluorophore when inserted into virtually any domain of another protein. Some of the proteins retained their signaling function, and the random nature of the transposition process revealed permissive sites for insertion that would not have been predicted on the basis of structural or functional models of how that protein works. Conclusion This technique should greatly speed the discovery of functional fusion proteins, genetically encodable sensors, and optimized fluorescence resonance energy transfer pairs.

Sheridan, Douglas L; Berlot, Catherine H; Robert, Antoine; Inglis, Fiona M; Jakobsdottir, Klara B; Howe, James R; Hughes, Thomas E

2002-01-01

421

Antarctica Part One  

NSDL National Science Digital Library

In this video, Jonathan treks all the way to Antarctica to investigate life south of the polar circle. Along the way he dives in the majestic kelp forests of Patagonia, where crabs rule the sea floor. Once he arrives in Antarctica, his adventures continue. He swims with penguins, dives under an iceberg, meets a massive jellyfish 3 feet wide, and has an incredible encounter with a Leopard seal, the apex predator of Antarctica. Part 1 finds Jonathan diving in Ushuaia, Patagonia in Argentina before boarding the ship to Antarctica, then he finally gets to Antarctica and meets some penguins! This program won a New England Emmy Award! Please see the accompanying lesson plan for educational objectives, discussion points and classroom activities.

Productions, Jonathan B.

2011-05-04

422

First observations of jelly-falls at the seafloor in a deep-sea fjord  

NASA Astrophysics Data System (ADS)

Faunal communities at the deep-sea floor mainly rely on the downward transport of particulate organic material for energy, which can come in many forms, ranging from phytodetritus to whale carcasses. Recently, studies have shown that the deep-sea floor may also be subsidized by fluxes of gelatinous material to the benthos. The deep-sea scyphozoan medusa Periphylla periphylla is common in many deep-sea fjords in Norway and recent investigations in Lurefjorden in western Norway suggest that the biomass of this jellyfish currently exceeds 50000 t here. To quantify the presence of dead P. periphylla jellyfish falls (hereafter termed jelly-falls) at the deep seafloor and the standing stock of carbon (C) and nitrogen (N) deposited on the seafloor by this species, we made photographic transects of the seafloor, using a 'Yo-Yo' camera system during an opportunistic sampling campaign in March 2011. Of 218 seafloor photographs taken, jelly-falls were present in five, which resulted in a total jelly-fall abundance of 1×10 -2 jelly-falls m -2 over the entire area surveyed. Summed over the entire area of seafloor photographed, 1×10 -2 jelly-falls m -2 was equivalent to a C- and N-biomass of 13 mg C m -2 and 2 mg N m -2. The contribution of each jelly-fall to the C- and N-amount of the sediment in the immediate vicinity of each fall (i.e. to sediment in each 3.02 m 2 image in which jelly-falls were observed) was estimated to be 568±84 mg C m -2 and 88±13 mg N m -2. The only megafaunal taxon observed around or on top of the jelly-falls was caridean shrimp (14±5 individuals jelly-fall -1), and shrimp abundance was significantly greater in photographs in which a jelly-fall was found (14±5 individuals image -1) compared to photographs in which no jelly-falls were observed (1.4±0.7 individuals image -1). These observations indicate that jelly-falls in this fjord can enhance the sedimentary C- and N-amount at the deep-sea floor and may provide nutrition to benthic and demersal faunas in this environment. However, organic enrichment from the jelly-falls found in this single sampling event and associated disturbance was highly localized.

Sweetman, Andrew K.; Chapman, Annelise

2011-12-01

423

Modeling and Thrust Optimization of a Bio-Inspired Pulsatile Jet Thruster  

NASA Astrophysics Data System (ADS)

A new type of thruster technology offers promising low speed maneuvering capabilities for underwater vehicles. Similar to the natural locomotion of squid and jellyfish the thruster successively forces fluid jets in and out of a small internal cavity. We investigate several properties of squid and jellyfish locomotion to drive the thruster design including actuation of nozzle geometry and vortex ring thrust augmentation. The thrusters are compact with no extruding components to negatively impact the vehicle's drag. These devices have thrust rise-times orders of magnitude faster than those reported for typical propeller thrusters, making them an attractive option for high accuracy underwater vehicle maneuvering. The dynamics of starting jet circulation, impulse, and kinetic energy are derived in terms of kinematics at the entrance boundary of a semi-infinite domain, specifically identifying the effect of a non-parallel incoming flow. A model for pressure at the nozzle is derived without the typical reliance on a predetermined potential function, making it a powerful tool for modeling any jet flow. Jets are created from multiple nozzle configurations to validate these models, and velocity and vorticity fields are determined using DPIV techniques. A converging starting jet resulted in circulation 90--100%, impulse 70--75%, and energy 105--135% larger than a parallel starting jet with identical volume flux and piston velocity, depending on the stroke ratio. The new model is a much better predictor of the jet properties than the standard 1D slug model. A simplified thrust model, was derived to describe the high frequency thruster characteristics. This model accurately predicts the average thrust, measured directly, for stroke ratios up to a critical value where the leading vortex ring separates from the remainder of the shear flow. A new model predicting the vortex ring pinch-off process is developed based on characteristic centerline velocities. The vortex ring pinch-off is coincides with this velocity criterion, for all cases tested. Piston velocity program and nozzle radius are optimized with respect to average thrust, and a quantity similar to propulsive efficiency. The average thrust is maximized by a critical nozzle radius. An approximate linear time-invariant (LTI) model of the thruster vehicle system was derived which categorizes maneuvers into different characteristic regimes. Initial thruster testing showed that open and closed loop frequency response were sufficiently approximated by the LTI model, and that the thruster is ideally suited for small scale high accuracy maneuvers.

Krieg, Michael W.

424

A bio-inspired shape memory alloy composite (BISMAC) actuator  

NASA Astrophysics Data System (ADS)

A beam-shape composite actuator using shape memory alloy (SMA) wires as the active component, termed a Bio-Inspired Shape Memory Alloy Composite (BISMAC), was designed to provide a large deformation profile. The BISMAC design was inspired by contraction of a jellyfish bell, utilizing the rowing mechanism for locomotion. Characterization of maximum deformation in underwater conditions was performed for different actuator configurations to analyze the effect of different design parameters, including silicone thickness, flexible steel thickness and distance between the SMA and flexible steel. A constant cross-section (CC)-BISMAC of length 16 cm was found to achieve deformation with a radius of curvature of 3.5 cm. Under equilibrium conditions, the CC-BISMAC was found to achieve 80% of maximum deformation, consuming 7.9 J/cycle driven at 16.2 V/0.98 A and a frequency of 0.25 Hz. A detailed analytical model was developed using the transfer matrix method and a 1D finite beam element (FE) model to simulate the behavior of the BISMAC incorporating gravity, buoyancy and SMA parameters. The FE and transfer matrix models had a maximum deformation error norm of 1.505 and 1.917 cm in comparison with experimentally observed beam deformation in the CC-BISMAC. The mean curvatures predicted by the FE and transfer matrix methods were 0.292 cm-1 and 0.295 cm-1 compared to a mean experimental curvature of 0.294 cm-1, a percentage error of -5.4% and 2.77%, respectively. Using the developed analytical model, an actuator design was fabricated mimicking the maximum deformation profile of jellyfish of the species Aurelia aurita (AA). The designed AA-BISMAC achieved a maximum curvature of 0.428 cm-1 as compared to 0.438 cm-1 for A. aurita with an average square root error of 0.043 cm-1, 10.2% of maximum A. aurita curvature.

Villanueva, A. A.; Joshi, K. B.; Blottman, J. B.; Priya, S.

2010-02-01

425

Transitioning a Chesapeake Bay Ecological Prediction System to Operations  

NASA Astrophysics Data System (ADS)

Ecological prediction of the impacts of physical, chemical, biological, and human-induced change on ecosystems and their components, encompass a wide range of space and time scales, and subject matter. They vary from predicting the occurrence and/or transport of certain species, such harmful algal blooms, or biogeochemical constituents, such as dissolved oxygen concentrations, to large-scale ecosystem responses and higher trophic levels. The timescales of ecological prediction, including guidance and forecasts, range from nowcasts and short-term forecasts (days), to intraseasonal and interannual outlooks (weeks to months), to decadal and century projections in climate change scenarios. The spatial scales range from small coastal inlets to basin and global scale biogeochemical and ecological forecasts. The types of models that have been used include conceptual, empirical, mechanistic, and hybrid approaches. This presentation will identify the challenges and progress toward transitioning experimental model-based ecological prediction into operational guidance and forecasting. Recent efforts are targeting integration of regional ocean, hydrodynamic and hydrological models and leveraging weather and water service infrastructure to enable the prototyping of an operational ecological forecast capability for the Chesapeake Bay and its tidal tributaries. A path finder demonstration predicts the probability of encountering sea nettles (Chrysaora quinquecirrha), a stinging jellyfish. These jellyfish can negatively impact safety and economic activities in the bay and an impact-based forecast that predicts where and when this biotic nuisance occurs may help management effects. The issuance of bay-wide nowcasts and three-day forecasts of sea nettle probability are generated daily by forcing an empirical habitat model (that predicts the probability of sea nettles) with real-time and 3-day forecasts of sea-surface temperature (SST) and salinity (SSS). In the first demonstration phase, the sea surface temperature (SST) and sea surface salinity (SSS) fields are generated by the Chesapeake Bay Operational Forecast System (CBOFS2), a 3-dimensional hydrodynamic model developed and operated by NOAA's National Ocean Service and run operationally at the National Weather Service National Centers for Environmental Prediction (NCEP). Importantly, this system is readily modified to predict the probability of other important target organisms, such as harmful algal blooms, biogeochemical constituents, such as dissolved oxygen concentration, and water-borne pathogens. Extending this initial effort includes advancement of a regional coastal ocean modeling testbed and proving ground. Such formal collaboration is intended to accelerate transition to operations and increase confidence and use of forecast guidance. The outcome will be improved decision making by emergency and resource managers, scientific researchers and the general public. The presentation will describe partnership plans for this testbed as well as the potential implications for the services and research community.

Brown, C.; Green, D. S.; Eco Forecasters

2011-12-01

426

Diversity and functional plasticity of eukaryotic selenoproteins: Identification and characterization of the SelJ family  

PubMed Central

Selenoproteins are a diverse group of proteins that contain selenocysteine (Sec), the 21st amino acid. In the genetic code, UGA serves as a termination signal and a Sec codon. This dual role has precluded the automatic annotation of selenoproteins. Recent advances in the computational identification of selenoprotein genes have provided a first glimpse of the size, functions, and phylogenetic diversity of eukaryotic selenoproteomes. Here, we describe the identification of a selenoprotein family named SelJ. In contrast to known selenoproteins, SelJ appears to be restricted to actinopterygian fishes and sea urchin, with Cys homologues only found in cnidarians. SelJ shows significant similarity to the jellyfish J1-crystallins and with them constitutes a distinct subfamily within the large family of ADP-ribosylation enzymes. Consistent with its potential role as a structural crystallin, SelJ has preferential and homogeneous expression in the eye lens in early stages of zebrafish development. A structural role for SelJ would be in contrast to the majority of known selenoenzymes. The unusually highly restricted phylogenetic distribution of SelJ, its specialization, and the comparative analysis of eukaryotic selenoproteomes reveal the diversity and functional plasticity of selenoproteins and point to a mosaic evolution of the use of Sec in proteins.

Castellano, Sergi; Lobanov, Alexey V.; Chapple, Charles; Novoselov, Sergey V.; Albrecht, Mario; Hua, Deame; Lescure, Alain; Lengauer, Thomas; Krol, Alain; Gladyshev, Vadim N.; Guigo, Roderic

2005-01-01

427

Visual wavelength discrimination by the loggerhead turtle, Caretta caretta.  

PubMed

Marine turtles are visual animals, yet we know remarkably little about how they use this sensory capacity. In this study, our purpose was to determine whether loggerhead turtles could discriminate between objects on the basis of color. We used light-adapted hatchlings to determine the minimum intensity of blue (450 nm), green (500 nm), and yellow (580 nm) visual stimuli that evoked a positive phototaxis (the phototaxis "threshold" [pt]). Juvenile turtles were later trained to associate each color (presented at 1 log unit above that color's pt) with food, then to discriminate between two colors (the original rewarded stimulus plus one of the other colors, not rewarded) when both were presented at 1 log unit above their pt. In the crucial test, turtles were trained to choose between the rewarded and unrewarded color when the colors varied in intensity. All turtles learned that task, demonstrating color discrimination. An association between blue and food was acquired in fewer trials than between yellow and food, perhaps because some prey of juvenile loggerheads in oceanic surface waters (jellyfishes, polyps, and pelagic gastropods) are blue or violet in color. PMID:22426631

Young, Morgan; Salmon, Michael; Forward, Richard

2012-02-01

428

Analysis of baroreflex sensitivity during undulation pump ventricular assist device support.  

PubMed

The aim of this study was to examine the baroreflex sensitivity (BRS), which involves the autonomic nervous system, in a goat with a chronically implanted undulation pump ventricular assist device (UPVAD). The UPVAD involved transforming the rotation of a brushless DC motor into an undulating motion by a disc attached via a special linking mechanism, and a jellyfish valve in the outflow cannula to prevent diastolic backflow. The pump was implanted into the thoracic cavity of a goat by a left thoracotomy, and the inflow and outflow cannulae were sutured to the apex of the left ventricle and to the descending aorta, respectively. The driving cable was wired percutaneously to an external controller. Electrocardiogram and hemodynamic waveforms were recorded at a sampling frequency of 1 kHz. BRS was determined when awake by the slope of the linear regression of R-R interval against mean arterial pressure changes, which were induced by the administration of methoxamine hydrochloride, both with continuous driving of the UPVAD as well as without assistance. BRS values during the UPVAD support and without assistance were 1.60 +/- 0.30 msec/mm Hg and 0.98 +/- 0.22 msec/mm Hg (n = 5, P < 0.05), respectively. BRS was significantly improved during left ventricular assistance. Therefore, UPVAD support might decrease sympathetic nerve activity and increase parasympathetic nerve activity to improve both microcirculation and organ function. PMID:19566735

Liu, Hongjian; Shiraishi, Yasuyuki; Zhang, Xiumin; Song, Hojin; Saijo, Yoshifumi; Baba, Atsushi; Yambe, Tomoyuki; Abe, Yusuke; Imachi, Kou

2009-07-01

429

Xenopus Nanos1 is required to prevent endoderm gene expression and apoptosis in primordial germ cells  

PubMed Central

Nanos is expressed in multipotent cells, stem cells and primordial germ cells (PGCs) of organisms as diverse as jellyfish and humans. It functions together with Pumilio to translationally repress targeted mRNAs. Here we show by loss-of-function experiments that Xenopus Nanos1 is required to preserve PGC fate. Morpholino knockdown of maternal Nanos1 resulted in a striking decrease in PGCs and a loss of germ cells from the gonads. Lineage tracing and TUNEL staining reveal that Nanos1-deficient PGCs fail to migrate out of the endoderm. They appear to undergo apoptosis rather than convert to normal endoderm. Whereas normal PGCs do not become transcriptionally active until neurula, Nanos1-depleted PGCs prematurely exhibit a hyperphosphorylated RNA polymerase II C-terminal domain at the midblastula transition. Furthermore, they inappropriately express somatic genes characteristic of endoderm regulated by maternal VegT, including Xsox17?, Bix4, Mixer, GATA4 and Edd. We further demonstrate that Pumilio specifically binds VegT RNA in vitro and represses, along with Nanos1, VegT translation within PGCs. Repressed VegT RNA in wild-type PGCs is significantly less stable than VegT in Nanos1-depleted PGCs. Our data indicate that maternal VegT RNA is an authentic target of Nanos1/Pumilio translational repression. We propose that Nanos1 functions to translationally repress RNAs that normally specify endoderm and promote apoptosis, thus preserving the germline.

Lai, Fangfang; Singh, Amar; King, Mary Lou

2012-01-01

430

Xenopus germline nanos1 is translationally repressed by a novel structure-based mechanism  

PubMed Central

The translational repressor Nanos is expressed in the germline and stem cell populations of jellyfish as well as humans. Surprisingly, we observed that unlike other mRNAs, synthetic nanos1 RNA translates very poorly if at all after injection into Xenopus oocytes. The current model of simple sequestration of nanos1 within germinal granules is insufficient to explain this observation and suggests that a second level of repression must be operating. We find that an RNA secondary structural element immediately downstream of the AUG start site is both necessary and sufficient to prevent ribosome scanning in the absence of a repressor. Accordingly, repression is relieved by small in-frame insertions before this secondary structure, or translational control element (TCE), that provide the 15 nucleotides required for ribosome entry. nanos1 is translated shortly after fertilization, pointing to the existence of a developmentally regulated activator. Oocyte extracts were rendered fully competent for nanos1 translation after the addition of a small amount of embryo extract, confirming the presence of an activator. Misexpression of Nanos1 in oocytes from unlocalized RNA results in abnormal development, highlighting the importance of TCE-mediated translational repression. Although found in prokaryotes, steric hindrance as a mechanism for negatively regulating translation is novel for a eukaryotic RNA. These observations unravel a new mode of nanos1 regulation at the post-transcriptional level that is essential for normal development.

Luo, Xueting; Nerlick, Steve; An, Weijun; King, Mary Lou

2011-01-01

431

Traditional Chinese food technology and cuisine.  

PubMed

From ancient wisdom to modern science and technology, Chinese cuisine has been established from a long history of the country and gained a global reputation of its sophistication. Traditional Chinese foods and cuisine that exhibit Chinese culture, art and reality play an essential role in Chinese people's everyday lives. Recently, traditional Chinese foods have drawn a great degree of attention from food scientists and technologists, the food industry, and health promotion institutions worldwide due to the extensive values they offer beyond being merely another ethnic food. These traditional foods comprise a wide variety of products, such as pickled vegetables, salted fish and jellyfish, tofu and tofu derived products, rice and rice snack foods, fermented sauces, fish balls and thousand-year-old eggs. An overview of selected popular traditional Chinese foods and their processing techniques are included in this paper. Further development of the traditional techniques for formulation and production of these foods is expected to produce economic, social and health benefits. PMID:15228981

Li, Jian-rong; Hsieh, Yun-Hwa P

2004-01-01

432

Cell-to-cell and long-distance trafficking of the green fluorescent protein in the phloem and symplastic unloading of the protein into sink tissues.  

PubMed Central

Macromolecular trafficking within the sieve element-companion cell complex, phloem unloading, and post-phloem transport were studied using the jellyfish green fluorescent protein (GFP). The GFP gene was expressed in Arabidopsis and tobacco under the control of the AtSUC2 promoter. In wild-type Arabidopsis plants, this promoter regulates expression of the companion cell-specific AtSUC2 sucrose-H+ symporter gene. Analyses of the AtSUC2 promoter-GFP plants demonstrated that the 27-kD GFP protein can traffic through plasmodesmata from companion cells into sieve elements and migrate within the phloem. With the stream of assimilates, the GFP is partitioned between different sinks, such as petals, root tips, anthers, funiculi, or young rosette leaves. Eventually, the GFP can be unloaded symplastically from the phloem into sink tissues, such as the seed coat, the anther connective tissue, cells of the root tip, and sink leaf mesophyll cells. In all of these tissues, the GFP can traffic cell to cell by symplastic post-phloem transport. The presented data show that plasmodesmata of the sieve element-companion cell complex, as well as plasmodesmata into and within the analyzed sinks, allow trafficking of the 27-kD nonphloem GFP protein. The data also show that the size exclusion limit of plasmodesmata can change during organ development. The results are also discussed in terms of the phloem mobility of assimilates and of small, low molecular weight companion cell proteins.

Imlau, A; Truernit, E; Sauer, N

1999-01-01

433

Ecological extinction and evolution in the brave new ocean  

PubMed Central

The great mass extinctions of the fossil record were a major creative force that provided entirely new kinds of opportunities for the subsequent explosive evolution and diversification of surviving clades. Today, the synergistic effects of human impacts are laying the groundwork for a comparably great Anthropocene mass extinction in the oceans with unknown ecological and evolutionary consequences. Synergistic effects of habitat destruction, overfishing, introduced species, warming, acidification, toxins, and massive runoff of nutrients are transforming once complex ecosystems like coral reefs and kelp forests into monotonous level bottoms, transforming clear and productive coastal seas into anoxic dead zones, and transforming complex food webs topped by big animals into simplified, microbially dominated ecosystems with boom and bust cycles of toxic dinoflagellate blooms, jellyfish, and disease. Rates of change are increasingly fast and nonlinear with sudden phase shifts to novel alternative community states. We can only guess at the kinds of organisms that will benefit from this mayhem that is radically altering the selective seascape far beyond the consequences of fishing or warming alone. The prospects are especially bleak for animals and plants compared with metabolically flexible microbes and algae. Halting and ultimately reversing these trends will require rapid and fundamental changes in fisheries, agricultural practice, and the emissions of greenhouse gases on a global scale.

Jackson, Jeremy B. C.

2008-01-01

434

[Ciliate diversity and spatiotemporal variation in surface sediments of Yangtze River estuary hypoxic zone].  

PubMed

By using denaturing gradient gel electrophoresis (DGGE) and sequencing as well as Ludox-QPS method, an investigation was made on the ciliate diversity and its spatiotemporal variation in the surface sediments at three sites of Yangtze River estuary hypoxic zone in April and August 2011. The ANOSIM analysis indicated that the ciliate diversity had significant difference among the sites (R = 0.896, P = 0.0001), but less difference among seasons (R = 0.043, P = 0.207). The sequencing of 18S rDNA DGGE bands revealed that the most predominant groups were planktonic Choreotrichia and Oligotrichia. The detection by Ludox-QPS method showed that the species number and abundance of active ciliates were maintained at a higher level, and increased by 2-5 times in summer, as compared with those in spring. Both the Ludox-QPS method and the DGGE technique detected that the ciliate diversity at the three sites had the similar variation trend, and the Ludox-QPS method detected that there was a significant variation in the ciliate species number and abundance between different seasons. The species number detected by Ludox-QPS method was higher than that detected by DGGE bands. Our study indicated that the ciliates in Yangtze River estuary hypoxic zone had higher diversity and abundance, with the potential to supply food for the polyps of jellyfish. PMID:23479889

Feng, Zhao; Kui-Dong, Xu; Zhao-Cui, Meng

2012-12-01

435

Polonium (210Po) and lead (210Pb) in marine organisms and their transfer in marine food chains.  

PubMed

The determination of (210)Po and (210)Pb was performed in marine organisms from the seashore to abyssal depths, encompassing a plethora of species from the microscopic plankton to the sperm whale. Concentrations of those radionuclides ranged from low values of about 5 × 10(-1) Bq kg(-1) (wet wt.) in jellyfish, to very high values of about of 3 × 10(4) Bq kg(-1) (wet wt.) in the gut walls of sardines, with a common pattern of (210)Po > (210)Pb.These radionuclides are primarily absorbed from water and concentrated by phyto- and microzooplankton, and then are transferred to the next trophic level along marine food chains. Investigation in epipelagic, mesopelagic, bathypelagic and abyssobenthic organisms revealed that (210)Po is transferred in the marine food webs with transfer factors ranging from 0.1 to 0.7, and numerically similar to those of the energy transfer in the marine food chains. As (210)Po preferentially binds to amino acids and proteins, its transfer in food chains likely traces protein transfer and, thus, (210)Po transfer factors are similar to ecotrophic coefficients. (210)Pb is transferred less efficiently in marine food chains and this contributes to increased (210)Po:(210)Pb activity ratios in some trophic levels. PMID:21106281

Carvalho, Fernando P

2010-11-23

436

Sprites in other planetary atmospheres  

NASA Astrophysics Data System (ADS)

Lightning have been detected in clouds on other planets either by direct imaging of the optical emissions from flashes emanating through the atmosphere or else by remote sensing of electromagnetic signals such as sferics or whistlers guided by the planet's magnetosphere. While the intensity of the electrical activity on Venus may be still inconclusive, there is little doubt, based on the Voyager, Galileo and Cassini missions, that lightning are prevalent on Jupiter and Saturn, and that their total power is much stronger than on Earth (Desch et al., 2002; Gurnett et al., 2005). Sprites are a type of a transient luminous emission which accompanies powerful lightning flashes (Lyons et al. 2001). They are caused the quasi-electrostatic electric field between the charged cloud top and the planetary ionosphere. They can take weird and magnificent shapes resembling jelly-fish, carrot heads, pearls or columns. On Earth, they emit in red and blue wavelengths, mostly from molecular Nitrogen species, and span a vertical range between 50 and 90 km. The emission spectra of sprites, their height and occurrence frequency reflect the properties of the planetary atmosphere and are directly related to the intensity of the parent lightning. We present results of theoretical calculations of the expected emissions in sprites, occurring above thunderstorms in the CO2 atmosphere of Venus and the Hydrogen-Helium atmospheres of Jupiter and Saturn. Detection methodology of sprites in planetary atmospheres by orbiting spacecraft will be discussed

Yair, Y.; Yaniv, R.

437

Poisoning, envenomation, and trauma from marine creatures.  

PubMed

In the course of their clinical work or during leisure activity, family physicians occasionally may encounter patients with injuries from marine creatures. Poisoning, envenomation, and direct trauma are all possible in the marine environment. Ciguatera poisoning can result from ingestion of predatory fish that have accumulated biotoxins. Symptoms can be gastrointestinal or neurologic, or mixed. Management is mostly symptomatic. Scombroid poisoning results from ingestion of fish in which histamine-like substances have developed because of improper refrigeration. Gastrointestinal and systemic symptoms occur. Treatment is based on antihistamines. Envenomations from jellyfish in U.S. waters and the Caribbean are painful but rarely deadly. Household vinegar deactivates the nematocysts, and manual removal of tentacles is important. Treatment is symptomatic. Heat immersion may help with the pain. Stingrays cause localized damage and a typically severe envenomation. The venom is deactivated by heat. The stingray spine, including the venom gland, typically is difficult to remove from the victim, and radiographs may be necessary to localize the spine or fragment. Surgical débridement occasionally is needed. Direct trauma can result from contact with marine creatures. Hemorrhage and tissue damage occasionally are severe. Infections with organisms unique to the marine environment are possible; antibiotic choices are based on location and type of injury. Shark attacks, although rare, require immediate attention. PMID:14989575

Perkins, R Allen; Morgan, Shannon S

2004-02-15

438

sine oculis in basal Metazoa.  

PubMed

We report the recovery of homologs of Six1/2/sine oculis (so), a homeodomain-containing member of the Six-gene family, from a diverse set of basal Metazoa, including representatives of the poriferan classes Demospongia, Calcarea and Hexactinellida, the cnidarian classes Hydrozoa, Scyphozoa and Anthozoa, as well as a ctenophore. so sequences were also recovered from a platyhelminth, an echiurid and two bivalve molluscs, members of the super-phyletic group Lophotrochozoa. In the case of the platyhelminth, multiple distinct so sequences were recovered, as well as a member of the related group Six4/5/D-Six4. Extended sequences of the so gene were recovered from the demosponge, Haliclona sp., and the scyphozoan Aurelia aurita via PCR, and 3' RACE. The affinities of all recovered sequences were assessed using a parsimony analysis based on both nucleic and amino acid sequence and using successive character weighting. Our results indicate that so is highly conserved across the animal kingdom. Preliminary expression data for Aurelia reveal that transcripts of the so homolog are present in the manubrium as well as in the rhopalia, which contain the statocyst and eyes, in the free-swimming ephyra and juvenile stages of these jellyfish. PMID:15221378

Bebenek, Ilona G; Gates, Ruth D; Morris, Joshua; Hartenstein, Volker; Jacobs, David K

2004-06-25

439

Proteome of Hydra Nematocyst*  

PubMed Central

Stinging cells or nematocytes of jellyfish and other cnidarians represent one of the most poisonous and sophisticated cellular inventions in animal evolution. This ancient cell type is unique in containing a giant secretory vesicle derived from the Golgi apparatus. The organelle structure within the vesicle comprises an elastically stretched capsule (nematocyst) to which a long tubule is attached. During exocytosis, the barbed part of the tubule is accelerated with >5 million g in <700 ns, enabling a harpoon-like discharge (Nüchter, T., Benoit, M., Engel, U., Ozbek, S., and Holstein, T. W. (2006) Curr. Biol. 16, R316–R318). Hitherto, the molecular components responsible for the organelle's biomechanical properties were largely unknown. Here, we describe the proteome of nematocysts from the freshwater polyp Hydra magnipapillata. Our analysis revealed an unexpectedly complex secretome of 410 proteins with venomous and lytic but also adhesive or fibrous properties. In particular, the insoluble fraction of the nematocyst represents a functional extracellular matrix structure of collagenous and elastic nature. This finding suggests an evolutionary scenario in which exocytic vesicles harboring a venomous secretome assembled a sophisticated predatory structure from extracellular matrix motif proteins.

Balasubramanian, Prakash G.; Beckmann, Anna; Warnken, Uwe; Schnolzer, Martina; Schuler, Andreas; Bornberg-Bauer, Erich; Holstein, Thomas W.; Ozbek, Suat

2012-01-01

440

Conservation status of Chinese species: (2) Invertebrates.  

PubMed

A total of 2441 invertebrate species were evaluated using the IUCN Red List Criteria and Regional Guidelines. Approximately 30 experts were involved in this project, which covered a wide range of species, including jellyfish, corals, planarians, snails, mollusks, bivalves, decapods, benthic crustaceans, arachnids (spiders, scorpions), butterflies, moths, beetles, sea cucumbers, sea urchins, sea stars, acorn worms and lancelets. In general, invertebrate species in China were found to be severely threatened, with 0.9% being critically endangered, 13.44% endangered and 20.63% vulnerable. All species of hermatypic corals and planarians are threatened. More than 80% of evaluated species face serious threat due to habitat destruction by coral collection, logging, non-woody vegetation collection, timber plantations, non-timber plantations, extraction and/or livestock. Other threats are intrinsic factors, harvesting by humans, alien invasive species and pollution. The main intrinsic factors contributing to the high levels of threat are limited dispersal and restricted range. No conservation measures have been taken for 70% of the threatened invertebrates evaluated. Existing conservation measures include: strengthening of national and international legislation (Convention on International Trade in Endangered Species of Wild Fauna and Flora), increasing public awareness, studying population trends/monitoring, and establishment of protected areas. The major conservation measure employed is strengthening of policies. Relative to the situation worldwide (2006 IUCN Red List), there is little information available about invertebrate extinctions in China. PMID:21396022

Xie, Yan; Wang, Sung

2007-06-01

441

Histopathological studies of sclerotia of phytopathogenic fungi parasitized by a GFP transformed Trichoderma virens antagonistic strain.  

PubMed

The gfp gene from the jellyfish Aequorea victoria, coding for the Green Fluorescent Protein (GFP), was used as a reporter gene to transform a Trichoderma virens strain I10, characterized as having a promising biocontrol activity against a large number of phytopathogenic fungi. On the basis of molecular and biological results, a stable GFP transformant was selected for further experiments. In order to evaluate the effects of GFP transformation on mycoparasitic ability of T. virens I10, sclerotia of Sclerotium rolfsii, Sclerotinia sclerotiorum and S. minor were inoculated with the T. virens strain I10 GFP transformant or the wild type strain. Statistical analysis of percentages of decayed sclerotia showed that the transformation of the antagonistic isolate with the GFP reporter gene did not modify mycoparasitic activity against sclerotia. Sclerotium colonization was followed by fluorescent microscopy revealing intracellular growth of the antagonist in the cortex (S. rolfsii) and inter-cellular growth in the medulla (S. rolfsii, and S. sclerotiorum). The uniformly distributed mycelium of T. virens just beneath the rind of sclerotia of both S. rolfsii and S. sclerotiorum suggests that the sclerotia became infected at numerous randomly distributed locations without any preferential point of entry. PMID:16388938

Sarrocco, Sabrina; Mikkelsen, Lisbeth; Vergara, Mariarosaria; Jensen, Dan Funck; Lübeck, Mette; Vannacci, Giovanni

2005-10-25

442

Perception of dimethyl sulfide (DMS) by loggerhead sea turtles: a possible mechanism for locating high-productivity oceanic regions for foraging.  

PubMed

During their long-distance migrations, sea turtles of several species feed on jellyfish and other invertebrates that are particularly abundant in ocean regions characterized by high productivity. An ability to distinguish productive oceanic regions from other areas, and to concentrate foraging activities in locations where prey density is highest, might therefore be adaptive. The volatile compound dimethyl sulfide (DMS) accumulates in the air above productive ocean areas such as upwelling and frontal zones. In principle, DMS might therefore serve as an indicator of high prey density for turtles. To determine whether turtles perceive DMS, juvenile loggerhead sea turtles (Caretta caretta) were placed into a water-filled arena in which DMS and other odorants could be introduced to the air above the water surface. Turtles exposed to air that had passed over a cup containing 10 nmol l(-1) DMS spent more time at the surface with their noses out of the water than control turtles, which were exposed to air that had passed over a cup containing distilled water. Odors that do not occur in the sea (cinnamon, jasmine and lemon) did not elicit increased surface time, implying that the response to DMS is unlikely to reflect a generalized response to any novel odor. The results demonstrate for the first time that sea turtles can detect DMS, an ability that might enable the identification of favorable foraging areas. PMID:23014568

Endres, Courtney S; Lohmann, Kenneth J

2012-10-15

443

Safety assessment of Apoaequorin, a protein preparation: subchronic toxicity study in rats.  

PubMed

Apoaequorin, a calcium-binding protein originally isolated from jellyfish is available commercially as a dietary supplement. The objective of the present study was to investigate potential adverse effects, if any, of Apoaequorin, a recombinant protein preparation, in rats following subchronic administration. For this study, Sprague-Dawley (Hsd:SD) rats (10/sex/group) were administered via oral gavage 0 (control), 92.6, 462.9, and 926.0mg/kg body weight (bw)/day of Apoaequorin preparation, for 90 days. The corresponding amount of Apoaequorin protein was 0, 66.7, 333.3 and 666.7 mg/kg bw/day, respectively. Administration of the Apoaequorin preparation did not result in any mortality. There were no clinical or ophthalmological signs, body weight, body weight gain, food consumption, food efficiency, clinical pathology or histopathological changes attributable to administration of Apoaequorin. Any changes noted were incidental and in agreement with those historically observed in the age and strain of rats used in this study. Based on the results of this study, the No Observed-Adverse-Effect Level (NOAEL) for Apoaequorin was determined as 666.7 mg/kg bw/day, the highest dose tested. PMID:23470325

Moran, Daniel L; Marone, Palma Ann; Bauter, Mark R; Soni, Madhu G

2013-03-05

444

Sequences encoding identical peptides for the analysis and manipulation of coding DNA.  

PubMed

The use of sequences encoding identical peptides (SEIP) for the in silico analysis of coding DNA from different species has not been reported; the study of such sequences could directly reveal properties of coding DNA that are independent of peptide sequences. For practical purposes SEIP might also be manipulated for e.g. heterologous protein expression. We extracted 1,551 SEIP from human and E. coli and 2,631 SEIP from human and D. melanogaster. We then analyzed codon usage and intercodon dinucleotide tendencies and found differences in both, with more conspicuous disparities between human and E. coli than between human and D. melanogaster. We also briefly manipulated SEIP to find out if they could be used to create new coding sequences. We hence attempted replacement of human by E. coli codons via dicodon exchange but found that full replacement was not possible, this indicated robust species-specific dicodon tendencies. To test another form of codon replacement we isolated SEIP from human and the jellyfish green fluorescent protein (GFP) and we then re-constructed the GFP coding DNA with human tetra-peptide-coding sequences. Results provide proof-of-principle that SEIP may be used to reveal differences in the properties of coding DNA and to reconstruct in pieces a protein coding DNA with sequences from a different organism, the latter might be exploited in heterologous protein expression. PMID:23861567

Sánchez, Joaquín

2013-05-08

445

Improving the spectral analysis of fluorescence resonance energy transfer in live cells: Application to interferon receptors and Janus kinases.  

PubMed

The observed Fluorescence Resonance Energy Transfer (FRET) between fluorescently labeled proteins varies in cells. To understand how this variation affects our interpretation of how proteins interact in cells, we developed a protocol that mathematically separates donor-independent and donor-dependent excitations of acceptor, determines the electromagnetic interaction of donors and acceptors, and quantifies the efficiency of the interaction of donors and acceptors. By analyzing large populations of cells, we found that misbalanced or insufficient expression of acceptor or donor as well as their inefficient or reversible interaction influenced FRET efficiency in vivo. Use of red-shifted donors and acceptors gave spectra with less endogenous fluorescence but produced lower FRET efficiency, possibly caused by reduced quenching of red-shifted fluorophores in cells. Additionally, cryptic interactions between jellyfish FPs artefactually increased the apparent FRET efficiency. Our protocol can distinguish specific and nonspecific protein interactions even within highly constrained environments as plasma membranes. Overall, accurate FRET estimations in cells or within complex environments can be obtained by a combination of proper data analysis, study of sufficient numbers of cells, and use of properly empirically developed fluorescent proteins. PMID:23796694

Krause, Christopher D; Digioia, Gina; Izotova, Lara S; Pestka, Sidney

2013-06-21

446

Tilting marks: Observations on tool marks resembling trace fossils and their morphological varieties  

NASA Astrophysics Data System (ADS)

Tilting marks, defined here as linear tool marks having transverse ornamentation, are produced in shallow water when the oscillatory action of waves of short wavelength tilt grounded objects rhythmically in such a way that they move and push sediment aside. These tool marks can resemble trace fossils, particularly if they are bilaterally symmetrical. Even asymmetrical objects can produce symmetrical tilting marks because the shape of the mark only depends on the geometry of the ground-touching part of the object, which may be partially floating. Objects of either soft or hard consistency, such as jellyfish or wood, respectively, can produce tilting marks. Tilting marks are normally produced linearly parallel or at an angle to the direction of wave propagation and do not show sharp bends or curves. Tilting marks can be formed on plane beds as well as rippled surfaces. Tilting marks can be distinguished from trace fossils by taking into account the geometry (symmetry), the direction of movement, and the mainly linear course and the internal pattern.

Wetzel, Andreas

2013-04-01

447

Yellow fluorescent protein phiYFPv (Phialidium): structure and structure-based mutagenesis.  

PubMed

The yellow fluorescent protein phiYFPv (?em(max) ? 537 nm) with improved folding has been developed from the spectrally identical wild-type phiYFP found in the marine jellyfish Phialidium. The latter fluorescent protein is one of only two known cases of naturally occurring proteins that exhibit emission spectra in the yellow-orange range (535-555 nm). Here, the crystal structure of phiYFPv has been determined at 2.05 Å resolution. The `yellow' chromophore formed from the sequence triad Thr65-Tyr66-Gly67 adopts the bicyclic structure typical of fluorophores emitting in the green spectral range. It was demonstrated that perfect antiparallel ?-stacking of chromophore Tyr66 and the proximal Tyr203, as well as Val205, facing the chromophore phenolic ring are chiefly responsible for the observed yellow emission of phiYFPv at 537 nm. Structure-based site-directed mutagenesis has been used to identify the key functional residues in the chromophore environment. The obtained results have been utilized to improve the properties of phiYFPv and its homologous monomeric biomarker tagYFP. PMID:23695245

Pletneva, Nadya V; Pletnev, Vladimir Z; Souslova, Ekaterina; Chudakov, Dmitry M; Lukyanov, Sergey; Martynov, Vladimir I; Arhipova, Svetlena; Artemyev, Igor; Wlodawer, Alexander; Dauter, Zbigniew; Pletnev, Sergei

2013-05-11

448

Sequences encoding identical peptides for the analysis and manipulation of coding DNA  

PubMed Central

The use of sequences encoding identical peptides (SEIP) for the in silico analysis of coding DNA from different species has not been reported; the study of such sequences could directly reveal properties of coding DNA that are independent of peptide sequences. For practical purposes SEIP might also be manipulated for e.g. heterologous protein expression. We extracted 1,551 SEIP from human and E. coli and 2,631 SEIP from human and D. melanogaster. We then analyzed codon usage and intercodon dinucleotide tendencies and found differences in both, with more conspicuous disparities between human and E. coli than between human and D. melanogaster. We also briefly manipulated SEIP to find out if they could be used to create new coding sequences. We hence attempted replacement of human by E. coli codons via dicodon exchange but found that full replacement was not possible, this indicated robust species-specific dicodon tendencies. To test another form of codon replacement we isolated SEIP from human and the jellyfish green fluorescent protein (GFP) and we then re-constructed the GFP coding DNA with human tetra-peptide-coding sequences. Results provide proof-of-principle that SEIP may be used to reveal differences in the properties of coding DNA and to reconstruct in pieces a protein coding DNA with sequences from a different organism, the latter might be exploited in heterologous protein expression.

Sanchez, Joaquin

2013-01-01

449

Measurements of Ca²? concentration with recombinant targeted luminescent probes.  

PubMed

In the last two decades the study of Ca(2+) homeostasis in living cells has been enhanced by the explosive development of genetically encoded Ca(2+)-indicators. The cloning of the Ca(2+)-sensitive photoprotein aequorin and of the green fluorescent protein (GFP) from the jellyfish Aequorea victoria has been enormously advantageous. As polypeptides, aequorin and GFP allow their endogenous production in cell systems as diverse as bacteria, yeast, slime molds, plants, and mammalian cells. Moreover, it is possible to specifically localize them within the cell by including defined targeting signals in the amino acid sequence. These two proteins have been extensively engineered to obtain several recombinant probes for different biological parameters, among which Ca(2+) concentration reporters are probably the most relevant. The GFP-based Ca(2+) probes and aequorin are widely employed in the study of intracellular Ca(2+) homeostasis. The new generation of bioluminescent probes that couple the Ca(2+) sensitivity of aequorin to GFP fluorescence emission allows real-time measurements of subcellular Ca(2+) changes in single cell imaging experiments and the video-imaging of Ca(2+) concentrations changes in live transgenic animals that express GFP-aequorin bifunctional probes. PMID:23007593

Ottolini, Denis; Calì, Tito; Brini, Marisa

2013-01-01

450

The effect of a variable diameter nozzle on starting jet formation and separation dynamics  

NASA Astrophysics Data System (ADS)

As a jet is forced through a nozzle, the shear layer formed at the interface rolls back on itself forming a vortex ring. At a critical point the circulation of the leading vortex ring becomes saturated causing it to "pinch-off" from the trailing shear flow, which then forms a wake of trailing vortices. Jet separation occurs at a nearly universal formation time (Gharib et. al. 1998). Both squid and jellyfish utilize the large impulse transfer associated with vortex ring formation to propel. Both swimmers are also known to actively change the diameter of the fluid interface during jetting. It was predicted by Mohseni et. al. (2001) that changing the diameter of the shear layer during formation can delay the vortex ring separation. We fabricated a prototype vortex ring generator which controls the jet diameter and jet velocity independently. This device was configured to eject a jet through a nozzle which was both opened and closed at a constant rate. The fluid driving mechanism was configured to compensate for the nozzle deformation and maintain a constant jet velocity. The jet formation dynamics were captured using a high speed camera and commercial DPIV software. The temporal evolution of the invariants of motion (circulation, energy and impulse) was determined from the DPIV velocity field. The invariance principle demonstrated a high accuracy before ring saturation, with some losses due to viscosity.

Krieg, Mike; Mohseni, Kamran

2010-11-01

451

A ridge tracking algorithm and error estimate for efficient computation of Lagrangian coherent structures  

NASA Astrophysics Data System (ADS)

A ridge tracking algorithm for the computation and extraction of Lagrangian coherent structures (LCS) is developed. This algorithm takes advantage of the spatial coherence of LCS by tracking the ridges which form LCS to avoid unnecessary computations away from the ridges. We also make use of the temporal coherence of LCS by approximating the time dependent motion of the LCS with passive tracer particles. To justify this approximation, we provide an estimate of the difference between the motion of the LCS and that of tracer particles which begin on the LCS. In addition to the speedup in computational time, the ridge tracking algorithm uses less memory and results in smaller output files than the standard LCS algorithm. Finally, we apply our ridge tracking algorithm to two test cases, an analytically defined double gyre as well as the more complicated example of the numerical simulation of a swimming jellyfish. In our test cases, we find up to a 35 times speedup when compared with the standard LCS algorithm.

Lipinski, Doug; Mohseni, Kamran

2010-03-01

452

A naturally occurring amino acid substitution in the voltage-dependent sodium channel selectivity filter affects channel gating.  

PubMed

The pore of sodium channels contains a selectivity filter made of 4 amino acids, D/E/K/A. In voltage sensitive sodium channel (Nav) channels from jellyfish to human the fourth amino acid is Ala. This Ala, when mutated to Asp, promotes slow inactivation. In some Nav channels of pufferfishes, the Ala is replaced with Gly. We studied the biophysical properties of an Ala-to-Gly substitution (A1529G) in rat Nav1.4 channel expressed in Xenopus oocytes alone or with a ?1 subunit. The Ala-to-Gly substitution does not affect monovalent cation selectivity and positively shifts the voltage-dependent inactivation curve, although co-expression with a ?1 subunit eliminates the difference between A1529G and WT. There is almost no difference in channel fast inactivation, but the ?1 subunit accelerates WT current inactivation significantly more than it does the A1529G channels. The Ala-to-Gly substitution mainly influences the rate of recovery from slow inactivation. Again, the ?1 subunit is less effective on speeding recovery of A1529G than the WT. We searched Nav channels in numerous databases and noted at least four other independent Ala-to-Gly substitutions in Nav channels in teleost fishes. Thus, the Ala-to-Gly substitution occurs more frequently than previously realized, possibly under selection for alterations of channel gating. PMID:23979192

Wu, Mingming; Ye, Na; Sengupta, Biswa; Zakon, Harold H

2013-08-25

453

(1)H, (13)C and (15)N assignments of the four N-terminal domains of human fibrillin-1.  

PubMed

Fibrillins are extracellular, disulphide-rich glycoproteins that form 10-12 nm diameter microfibrils in connective tissues. They are found in the majority of higher animals, from jellyfish to humans. Fibrillin microfibrils confer properties of elasticity and strength on connective tissue and regulate growth factor availability in the extracellular matrix (ECM). Mutations in FBN1, the human gene encoding the fibrillin-1 isoform, are linked to several inherited connective tissue disorders. The fibrillin-1 N-terminus forms many functionally-important interactions, both with other fibrillin molecules and various ECM components. In particular, the first four domains, the fibrillin unique N-terminal (FUN) and three epidermal growth factor (EGF)-like domains (FUN-EGF3), are implicated in microfibril assembly and growth factor sequestration. The structure of these domains, which comprise 134 residues, is unknown. We have produced a recombinant fragment corresponding to this region of human fibrillin-1. Here, we report (1)H, (13)C and (15)N resonance assignments of the FUN-EGF3 fragment. Assignments will facilitate structure determination, analysis of interdomain dynamics and the mapping of interaction surfaces. PMID:23264024

Yadin, David A; Robertson, Ian B; Jensen, Sacha A; Handford, Penny A; Redfield, Christina

2012-12-23

454

Analysis of soluble protein contents from the nematocysts of a model sea anemone sheds light on venom evolution.  

PubMed

The nematocyst is one of the most complex intracellular structures found in nature and is the defining feature of the phylum Cnidaria (sea anemones, corals, jellyfish, and hydroids). This miniature stinging organelle contains and delivers venom into prey and foe yet little is known about its toxic components. In the present study, we identified by tandem mass spectrometry 20 proteins released upon discharge from the nematocyst of the model sea anemone Nematostella vectensis. The availability of genomic and transcriptomic data for this species enabled accurate identification and phylogenetic study of these components. Fourteen of these proteins could not be identified in other animals suggesting that they might be the products of taxonomically restricted genes, a finding which fits well their origin from a taxon-specific organelle. Further, we studied by in situ hybridization the localization of two of the transcripts encoding the putative nematocyst venom proteins: a metallopeptidase related to the Tolloid family and a cysteine-rich protein. Both transcripts were detected in nematocytes, which are the cells containing nematocysts, and the metallopeptidase was found also in pharyngeal gland cells. Our findings reveal for the first time the possible venom components of a sea anemone nematocyst and suggest their evolutionary origins. PMID:23151943

Moran, Yehu; Praher, Daniela; Schlesinger, Ami; Ayalon, Ari; Tal, Yossi; Technau, Ulrich

2012-11-15

455

A potential-flow, deformable-body model for fluid-structure interactions with compact vorticity: application to animal swimming measurements  

NASA Astrophysics Data System (ADS)

This paper presents an approach to quantify the unsteady fluid forces, moments and mass transport generated by swimming animals, based on measurements of the surrounding flow field. These goals are accomplished within a framework that is independent of the vorticity field, making it unnecessary to directly resolve boundary layers on the animal, body-vortex interactions, or interactions among vortex lines in the wake. Instead, the method identifies Lagrangian coherent structures in the flow, whose dynamics in flows with compact vorticity are shown to be well approximated by potential flow concepts, especially the Kirchhoff and deformation potentials from deformable body theory. Examples of the application of these methods are given for pectoral fin locomotion of the bluegill sunfish and undulatory swimming of jellyfish, and the methods are validated by analysis of a canonical starting vortex ring flow. The transition to a Lagrangian approach toward animal swimming measurements suggests the possibility of implementing recently developed particle tracking (vis-à-vis DPIV) techniques for fully three-dimensional measurements of animal swimming.

Peng, Jifeng; Dabiri, John O.

456

Stereo observations of sprites in support of NHK project: The Cosmic Shore  

NASA Astrophysics Data System (ADS)

High speed (~10,000 frames per second) stereo observations of sprites were made during a combined aircraft and ground-based campaign June 27 to July 10, 2011. Observations were made from two Gulfstream IV jet aircraft, based at Denver Centennial, and from the ground at Langmuir Laboratory, NM, Yucca Ridge Field Station, CO, and Rapid City, SD. The aircraft were flown at an altitude of 14 km along same track positioned 200-300 km from sprite producing thunderstorms. The aircraft separation was 30-50 km to provide good stereo viewing. The sprite activity during the campaign was good with several very large sprites, so-called jellyfish or super sprites. A number of sprites were recorded from both aircraft, and several from aircraft and one ground site. These recordings will in particular allow us to follow the development and the track of individual sprite streamers. In addition we recorded ground-based electromagnetic signals from the causal lightning strikes. On the last flight we observed a number of blue jets coming from a spatially small area, which may have been associated with local strong precipitation and hail.

Inoue, T.; Stenbaek-Nielsen, H. C.; McHarg, M. G.; Haaland, R. K.; Kammae, T.; Takahashi, Y.; Sato, M.; Cummer, S. A.; Yair, Y.; Lyons, W.; Ahrns, J.; Yukman, P.; Kudo, T.; Warner, T. A.; Sonnenfeld, R. G.; Li, J.; Lu, G.

2011-12-01

457

One-piece micropumps from liquid crystalline core-shell particles  

NASA Astrophysics Data System (ADS)

Responsive polymers are low-cost, light weight and flexible, and thus an attractive class of materials for the integration into micromechanical and lab-on-chip systems. Triggered by external stimuli, liquid crystalline elastomers are able to perform mechanical motion and can be utilized as microactuators. Here we present the fabrication of one-piece micropumps from liquid crystalline core-shell elastomer particles via a microfluidic double-emulsion process, the continuous nature of which enables a low-cost and rapid production. The liquid crystalline elastomer shell contains a liquid core, which is reversibly pumped into and out of the particle by actuation of the liquid crystalline shell in a jellyfish-like motion. The liquid crystalline elastomer shells have the potential to be integrated into a microfluidic system as micropumps that do not require additional components, except passive channel connectors and a trigger for actuation. This renders elaborate and high-cost micromachining techniques, which are otherwise required for obtaining microstructures with pump function, unnecessary.

Fleischmann, Eva-Kristina; Liang, Hsin-Ling; Kapernaum, Nadia; Giesselmann, Frank; Lagerwall, Jan; Zentel, Rudolf

2012-11-01

458

Neuroglobins, pivotal proteins associated with emerging neural systems and precursors of metazoan globin diversity.  

PubMed

Neuroglobins, previously thought to be restricted to vertebrate neurons, were detected in the brain of a photosymbiotic acoel, Symsagittifera roscoffensis, and in neurosensory cells of the jellyfish Clytia hemisphaerica. For the neuroglobin of S. roscoffensis, a member of a lineage that originated either at the base of the bilateria or of the deuterostome clade, we report the ligand binding properties, crystal structure at 2.3 ?, and brain immunocytochemical pattern. We also describe in situ hybridizations of two neuroglobins specifically expressed in differentiating nematocytes (neurosensory cells) and in statocytes (ciliated mechanosensory cells) of C. hemisphaerica, a member of the early branching animal phylum cnidaria. In silico searches using these neuroglobins as queries revealed the presence of previously unidentified neuroglobin-like sequences in most metazoan lineages. Because neural systems are almost ubiquitous in metazoa, the constitutive expression of neuroglobin-like proteins strongly supports the notion of an intimate association of neuroglobins with the evolution of animal neural systems and hints at the preservation of a vitally important function. Neuroglobins were probably recruited in the first protoneurons in early metazoans from globin precursors. Neuroglobins were identified in choanoflagellates, sponges, and placozoans and were conserved during nervous system evolution. Because the origin of neuroglobins predates the other metazoan globins, it is likely that neuroglobin gene duplication followed by co-option and subfunctionalization led to the emergence of globin families in protostomes and deuterostomes (i.e. convergent evolution). PMID:23288852

Lechauve, Christophe; Jager, Muriel; Laguerre, Laurent; Kiger, Laurent; Correc, Gaëlle; Leroux, Cédric; Vinogradov, Serge; Czjzek, Mirjam; Marden, Michael C; Bailly, Xavier

2013-01-03

459

Independent evolution of striated muscles in cnidarians and bilaterians.  

PubMed

Striated muscles are present in bilaterian animals (for example, vertebrates, insects and annelids) and some non-bilaterian eumetazoans (that is, cnidarians and ctenophores). The considerable ultrastructural similarity of striated muscles between these animal groups is thought to reflect a common evolutionary origin. Here we show that a muscle protein core set, including a type II myosin heavy chain (MyHC) motor protein characteristic of striated muscles in vertebrates, was already present in unicellular organisms before the origin of multicellular animals. Furthermore, 'striated muscle' and 'non-muscle' myhc orthologues are expressed differentially in two sponges, compatible with a functional diversification before the origin of true muscles and the subsequent use of striated muscle MyHC in fast-contracting smooth and striated muscle. Cnidarians and ctenophores possess striated muscle myhc orthologues but lack crucial components of bilaterian striated muscles, such as genes that code for titin and the troponin complex, suggesting the convergent evolution of striated muscles. Consistently, jellyfish orthologues of a shared set of bilaterian Z-disc proteins are not associated with striated muscles, but are instead expressed elsewhere or ubiquitously. The independent evolution of eumetazoan striated muscles through the addition of new proteins to a pre-existing, ancestral contractile apparatus may serve as a model for the evolution of complex animal cell types. PMID:22763458

Steinmetz, Patrick R H; Kraus, Johanna E M; Larroux, Claire; Hammel, Jörg U; Amon-Hassenzahl, Annette; Houliston, Evelyn; Wörheide, Gert; Nickel, Michael; Degnan, Bernard M; Technau, Ulrich

2012-07-12

460

Molecular organization of various collagen fragments as revealed by atomic force microscopy and diffusion-ordered NMR spectroscopy.  

PubMed

Heterogeneous mixtures of collagen fragments can be used as nutrition supplement or as key ingredients for ointments with therapeutic relevance in wound healing. Some mixtures of collagen fragments are referred to as collagen hydrolysates owing to the production process with hydrolytic enzymes. Since the precise composition of collagen hydrolysates is generally unknown, it is of interest to analyze samples containing various collagen fragments with appropriate biophysical methods. Any product optimization without a profound knowledge concerning the size and the molecular weight distribution of its components is nearly impossible. It turned out that a combination of AFM methods with NMR techniques is exceptionally suited to examine the size range and the aggregation behavior of the collagen fragments in the hydrolysates of fish, jellyfish, chicken, porcine and bovine collagen. Supported by molecular modeling calculations, the AFM and NMR experiments provide a detailed knowledge about the composition of collagen hydrolysates and collagen ointments. Furthermore, the data allow a correlation between the size of the fragments and their potential bioactivity. PMID:22855352

Stötzel, Sabine; Schurink, Marloes; Wienk, Hans; Siebler, Uschi; Burg-Roderfeld, Monika; Eckert, Thomas; Kulik, Bianca; Wechselberger, Rainer; Sewing, Judith; Steinmeyer, Jürgen; Oesser, Steffen; Boelens, Rolf; Siebert, Hans-Christian

2012-07-31