Artículos de revistas: "Sea urchin spines"

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NASSAB, R., S. RAYATT y F. PEART. "The Management of Hand Injuries Caused by Sea Urchin Spines". Journal of Hand Surgery 30, n.º 4 (agosto de 2005): 432–33. http://dx.doi.org/10.1016/j.jhsb.2005.04.001.

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Injuries to the hand by sea urchin spines are not commonly seen in the United Kingdom. There are many varieties of sea urchins (Echinoidea) throughout the world. They have a spherical calcium carbonate exoskeleton covered with spines. Certain varieties may be venomous, in particular the flower urchin ( Toxopneustes pileolus) found in the Indo-Pacific oceans. Injury may also be caused by the urchin spines or pedicellaria (delicate seizing organs equipped with jaws) ( Auerbach, 1991 ; Smith, 2002 ). A small number of hand injuries associated with sea urchin spines have been reported in the literature.

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Rossetto, André Luiz, Jamesson de Macedo Mora y Vidal Haddad Junior. "Sea urchin granuloma". Revista do Instituto de Medicina Tropical de São Paulo 48, n.º 5 (octubre de 2006): 303–6. http://dx.doi.org/10.1590/s0036-46652006000500013.

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Injuries caused by venomous and poisonous aquatic animals may provoke important morbidity in humans. The phylum Echinoderma include more than 6000 species of starfish, sea urchins, sand dollars, and sea cucumbers some of which have been found responsible for injuries to humans. Initial injuries by sea urchins are associated with trauma and envenomation, but later effects can be observed. Sea urchin granuloma is a chronic granulomatous skin disease caused by frequent and successive penetration of sea urchin spines which have not been removed from wounds. The authors report a typical case of sea urchin granuloma in a fisherman and its therapeutic implications.

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Goetz, Andreas, Erika Griesshaber y Wolfgang W. Schmahl. "An Easy Approach to Increase the Precision of EBSD Analysis – Examples from a Sea Urchin Calcite Study". Solid State Phenomena 160 (febrero de 2010): 229–34. http://dx.doi.org/10.4028/www.scientific.net/ssp.160.229.

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Sea urchins mineralize Mg-calcite skeletons, both, within their exoskeletons as well as in their spines. In this study we have investigated sea urchin spines of the species Amblypneustes pachistus. The spines are round and consist of several wedges that extend from the base to the tip of the spine. The wedges are connected to each other by porous calcite. Rocking curves of the spines show a distribution of 0.5° of the 110 reflection, with the domains being misoriented by 0.1° to each other. In our EBSD system the average mean angular (MAD) deviation is 0.3°. This is higher than the signal that is needed for the detection of small misorientations of domains within a sea urcin spine. In order to increase the precision (not the accuracy) of the EBSD measurements several factors, such as geometric artifacts and charging of calcite were minimized. Handling of these factors and utilizing the subsequently described statistical approach allowed for the identification of different domains within the spines. It further allowed calculating the degree of misorientation between these domains. Our EBSD analyses and the subsequent evaluation of the data show that the wedges forming the spines of Amblypneustes pachistus are mosaic crystals. The misorientation of the wedges to each other increases from the base of the spine towards its tip. The here proposed method for increasing the precision of the angular resolution showed reproducibility on silicon of 0.05°.

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Tsafnat, Naomi, John D. Fitz Gerald, Hai N. Le y Zbigniew H. Stachurski. "Micromechanics of Sea Urchin Spines". PLoS ONE 7, n.º 9 (11 de septiembre de 2012): e44140. http://dx.doi.org/10.1371/journal.pone.0044140.

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Stiefel, Klaus y Glyn Barrett. "Sea Urchins as an Inspiration for Robotic Designs". Journal of Marine Science and Engineering 6, n.º 4 (10 de octubre de 2018): 112. http://dx.doi.org/10.3390/jmse6040112.

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Neuromorphic engineering is the approach to intelligent machine design inspired by nature. Here, we outline possible robotic design principles derived from the neural and motor systems of sea urchins (Echinoida). Firstly, we review the neurobiology and locomotor systems of sea urchins, with a comparative emphasis on differences to animals with a more centralized nervous system. We discuss the functioning and enervation of the tube feet, pedicellariae, and spines, including the limited autonomy of these structures. We outline the design principles behind the sea urchin nervous system. We discuss the current approaches of adapting these principles to robotics, such as sucker-like structures inspired by tube feet and a robotic adaptation of the sea urchin jaw, as well as future directions and possible limitations to using these principles in robots.

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Yu, Yushi, Jiangnan Sun, Yaqing Chang y Chong Zhao. "High fitness areas drive the aggregation of the sea urchin Mesocentrotus nudus". PeerJ 10 (19 de enero de 2022): e12820. http://dx.doi.org/10.7717/peerj.12820.

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Sea urchin aggregation is a common phenomenon in coastlines. However, it remains controversial whether sea urchins form resource aggregations or behavioral aggregations in a non-spawning season. To clarify, we studied the aggregative responses to food and predators in the sea urchin Mesocentrotus nudus when high fitness areas (HFAs) were scarce versus sufficient. By taking the occupied area of each sea urchin (test diameter + spines = 4.5 cm) as a square (4.5 cm × 4.5 cm), we set scarce HFAs for the sea urchins in Experiment 1 (the squares of HFAs: the area occupied by experimental sea urchins = 1:1) and sufficient HFAs for the sea urchins in Experiment 2 (the squares of HFAs: the area occupied by experimental sea urchins = 2:1). If M. nudus form resource aggregations, they would aggregate passively under the scarce HFAs conditions, but not in the sufficient HFAs conditions. Conversely, if M. nudus form behavioral aggregation, aggregation would occur in both scarce and sufficient HFAs. The present results showed that in the scarce HFAs, M. nudus in the food and predator groups were significantly closer to the food and further from predators, and had significantly more aggregated numbers in HFAs than those in the control group. Sea urchins did not aggregate in response to food or predators under the sufficient HFAs, although significantly more sea urchins of the experimental group was found in HFAs than that of the control group. Sea urchins (at least M. nudus) form resource aggregations that are driven by the scarce HFAs. This provides valuable information into the mechanisms of the aggregation of sea urchins.

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Haddad Junior, Vidal. "Observation of initial clinical manifestations and repercussions from the treatment of 314 human injuries caused by black sea urchins (Echinometra lucunter) on the southeastern Brazilian coast". Revista da Sociedade Brasileira de Medicina Tropical 45, n.º 3 (junio de 2012): 390–92. http://dx.doi.org/10.1590/s0037-86822012000300021.

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INTRODUCTION: Injuries caused by sea urchins are the most common caused by marine animals in humans in Brazil, with the black sea urchin (Echinometra lucunter) causing the most injuries to bathers. METHODS: This study observed 314 human wounds with emphasis on the early observation of clinical signs and symptoms and their implications on the recommended treatment. RESULTS: All the injuries were caused by black sea urchins and were observed in bathers. The lesions and the pain were associated with penetration of the spines; there was no early inflammation or pain without pressure on the wounded places. Complications arising from this kind on injury, including infections and foreign body granulomas, are associated with the permanence of the spines in the wounds. CONCLUSIONS: The study confirmed that this kind of injury is the most common accident caused by aquatic animals in Brazil. The main therapeutical recommendation is early removal of the spines to prevent late complications, such as infections and the formation of foreign body granulomas.

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Denny, M. y B. Gaylord. "Why the urchin lost its spines: hydrodynamic forces and survivorship in three echinoids". Journal of Experimental Biology 199, n.º 3 (1 de marzo de 1996): 717–29. http://dx.doi.org/10.1242/jeb.199.3.717.

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Two species of sea urchins (Colobocentrotus atratus and Echinometra mathaei) commonly co-occur on wave-swept intertidal shores in the Indo West Pacific. E. mathaei is a typical spiny urchin and is confined to cavities in the rock. In contrast, C. atratus has an unusual morphology, in which the spines are much reduced, and is found on substrata fully exposed to wave-induced velocities and accelerations. Previous researchers have suggested that spine reduction may therefore be a morphological adaptation to hydrodynamic forces. However, measurement of the drag, lift and accelerational forces on sea urchins show that the adaptive significance of spine reduction is less straightforward than it initially appears. The reduction in drag in C. atratus as compared with that in E. mathaei is to a large extent offset by an increase in lift. Instead, the 'streamlined' morphology of C. atratus seems best adapted to provide a reduction in the force imposed by water acceleration, thereby making it feasible for C. atratus to venture safely into the tumultuous flows of the surf zone.

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Rodríguez-Barreras, Ruber, Anelisse Dominicci-Maura, Eduardo L. Tosado-Rodríguez y Filipa Godoy-Vitorino. "The Epibiotic Microbiota of Wild Caribbean Sea Urchin Spines Is Species Specific". Microorganisms 11, n.º 2 (3 de febrero de 2023): 391. http://dx.doi.org/10.3390/microorganisms11020391.

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Caribbean sea urchins are marine invertebrates that have experienced a decline over the years. Studies on sea urchins have focused primarily on the microbiome of the coelomic fluid or the gut microbiota. In this study, the epibiota community associated with four wild Caribbean sea urchin species, Lytechinus variegatus, Echinometra lucunter, Tripneustes ventricosus, and Diadema antillarum, was characterized for the first time. Using 57 sea urchin animal samples, we evaluated the influence of animal species, trophic niches, and geographical location on the composition of the epibiotic microbiota. We found significant differences in the bacterial biota among species and trophic niches, but not among geographical locations. L. variegatus exhibited the highest alpha diversity with high dominance of Fusobacteria, Planctomycetes, and Cyanobacteria, whereas T. ventricosus and D. antillarum were dominated by Firmicutes. T. ventricosus inhabiting the seagrass biotope dominated by Thalassia testudinum meadows had mostly Endozoicomonas. In contrast, samples located in the reef (dominated by corals and other reef builders) had a higher abundance of Kistimonas and Photobacterium. Our findings confirm that the epibiotic microbiota is species-specific, but also niche-dependent, revealing the trophic networks emerging from the organic matter being recycled in the seagrass and reef niches. As echinoids are important grazers of benthic communities, their microbiota will likely influence ecosystem processes.

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Solari, Paolo, Giorgia Sollai, Viviana Pasquini, Angelica Giglioli, Roberto Crnjar y Piero Addis. "Blue-Green Algae as Stimulating and Attractive Feeding Substrates for a Mediterranean Commercial Sea Urchin Species, Paracentrotus lividus". Life 13, n.º 7 (5 de julio de 2023): 1510. http://dx.doi.org/10.3390/life13071510.

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Sea urchins rely on chemical senses to localize suitable food resources, therefore representing model species for chemosensory studies. In the present study, we investigated the chemical sensitivity of the Mediterranean sea urchin Paracentrotus lividus to the blue-green alga Aphanizomenon flos-aquae, namely “Klamath”, and to a few amino acids chosen from the biochemical composition of the same algae. To this end, we used the “urchinogram” method, which estimates the movement rate of the sea urchins in response to chemicals. Our results showed that Klamath represents a strong chemical stimulus for P. lividus as it elicits an overall movement of spines, pedicellariae, and tube feet coupled, in some cases, to a coordinated locomotion of the animals. Sea urchins also displayed a sensitivity, even if to a lesser extent, to leucine, threonine, arginine, and proline, thus implying that the amino acids contained in Klamath may account, at least in part, for the stimulating effects exerted by the whole algae. Additionally, our results show that Klamath, as well as spirulina, another blue-green alga with high nutritional value, is very attractive for this sea urchin species. These findings gain further importance considering the potential profit of echinoderms for commercial consumers and their growing role in aquaculture. Klamath and spirulina combine high nutritional profiles with attractive and stimulating abilities and may be considered potential valuable feed supplements in sea urchin aquaculture.

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Brasseur, Lola, Guillaume Caulier, Patrick Flammang, Pascal Gerbaux y Igor Eeckhaut. "Mapping of Spinochromes in the Body of Three Tropical Shallow Water Sea Urchins". Natural Product Communications 13, n.º 12 (diciembre de 2018): 1934578X1801301. http://dx.doi.org/10.1177/1934578x1801301222.

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Sea urchin pigments, also known as spinochromes or polyhydroxynaphthoquinones (PHNQ) have been well studied for their bioactive properties like anti-bacterial, fungicidal, antioxidant and pro-inflammatory effects. Moreover, many studies have analyzed and identified these pigments in sea urchin tests and spines but, and to the best of our knowledge, never in their body compartments or in a quantitative manner. The aim of this work was to investigate the diversity and concentration of pigments in three sea urchins localized in the same coral reef in Madagascar ( Diadema savignyi, Tripneustes gratilla and Toxopneustes pileolus). Their pigment distribution patterns were compared and linked to their behavior in order to understand better the implication of spinochromes in a sea urchin's life. Analyses and quantifications by LC-MS showed the presence of 11 different spinochromes with principally two kinds of patterns. First, D. savignyi showed a high concentration in all its body compartments with a predominance for Echinochrome A and Spinochrome D – Iso 3, a pattern close to the E. mathaei distribution found in our previous study. The presence of these pigments has been linked to their bioactive properties and suggested their implications in UV radiation protection, in reproduction, in feeding as well as in their immune systems. Secondly, T. gratilla and T. pileolus presented few spinochromes, which could explain their restricted diet and their covering behavior facing sunlight. Moreover, the absence of pigments in their gonads could be explained by their seasonal spawning occurring before our collection period. Nevertheless, the near absence of spinochromes may be counterbalanced by other bioactive compounds like their toxic proteins, which may act as either a defense mechanism or immune agents, or like carotenoid pigments already shown in sea urchin and acting as defense agents. In conclusion, spinochromes, and pigments in general, seem to play many roles in sea urchin ecology. Their highly reactive structures confer them with strong bioactive properties involved in most parts of their metabolic system and clearly participate in the survival of the sea urchins.

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Ayyagari, Archana y Ramesh Babu Kondamudi. "Ecological Significance of the Association betweenStomopneustes variolaris(Echinoidea) andLumbrineris latreilli(Polychaeta) from Visakhapatnam Coast, India". Journal of Marine Biology 2014 (2014): 1–4. http://dx.doi.org/10.1155/2014/640785.

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The present study reports a new association between the sea urchinStomopneustes variolaris(Lamarck, 1816) and the polychaeteLumbrineris latreilli(Audouin & Milne Edwards, 1834) based on the specimens collected intertidally at Bay of Bengal (Visakhapatnam, east coast of India). Out of 60 sea urchins collected, 10 (16.67%) were associated with the polychaete. The prevalence increased with the increasing sea urchin test diameter. All polychaetes were exclusively found between the spines, in the aboral region of the host. This association protects the polychaete from the predators during displacement from its natural habitat.

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Barrett, Glyn, Dominic Revell, Lucy Harding, Ian Mills, Axelle Jorcin y Klaus Stiefel. "Tool Use by Four Species of Indo-Pacific Sea Urchins". Journal of Marine Science and Engineering 7, n.º 3 (18 de marzo de 2019): 69. http://dx.doi.org/10.3390/jmse7030069.

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We compared the covering behavior of four sea urchin species, Tripneustes gratilla, Pseudoboletia maculata, Toxopneustes pileolus, and Salmacis sphaeroides found in the waters of Malapascua Island, Cebu Province and Bolinao, Panagsinan Province, Philippines. Specifically, we measured the amount and type of covering material on each sea urchin, and in several cases, the recovery of debris material after stripping the animal of its cover. We found that Tripneustes gratilla and Salmacis sphaeroides have a higher affinity for plant material, especially seagrass, compared to Pseudoboletia maculata and Toxopneustes pileolus, which prefer to cover themselves with coral rubble and other calcified material. Only in Toxopneustes pileolus did we find a significant corresponding depth-dependent decrease in total cover area, confirming previous work that covering behavior serves as a protection mechanism against UV radiation. We found no dependence of particle size on either species or size of sea urchin, but we observed that larger sea urchins generally carried more and heavier debris. We observed a transport mechanism of debris onto the echinoid body surface utilizing a combination of tube feet and spines. We compare our results to previous studies, comment on the phylogeny of sea urchin covering behavior, and discuss the interpretation of this behavior as animal tool use.

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Ouréns, Rosana, Juan Freire, Jose A. Vilar y Luis Fernández. "Influence of habitat and population density on recruitment and spatial dynamics of the sea urchin Paracentrotus lividus: implications for harvest refugia". ICES Journal of Marine Science 71, n.º 5 (2 de enero de 2014): 1064–72. http://dx.doi.org/10.1093/icesjms/fst201.

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Abstract We studied the spatial variation in recruitment and the population dynamics of the sea urchin Paracentrotus lividus, analysing the effect of depth and presence of sea urchin aggregations on population structure. Over 90% of the observed recruits (individuals under 1 year of age) were concentrated in aggregations found in shallow waters. In these areas, a positive linear relationship was found between adult and recruit density, possibly due to higher survival rates of juveniles taking refuge among the spines of adults. The scarcity of recruits and the presence of adult sea urchins at depths of 8 and 12 m suggest the migration of part of the population towards deep areas when individuals reach a size of ∼40 mm. In light of these results, the implementation of harvest refugia for sea urchins in shallow areas could constitute an effective fishery management tool for this species. High population densities could enhance recruitment, given the inverse density dependence of this process, while their migratory pattern would guarantee biomass exportation towards deeper fishing grounds.

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Mulyana, Jeane Siswitasari, Nur Astri Melinia y Gres Maretta. "Biodiversity of Sea Urchin in the Area of Sari Ringgung Beach, Pesawaran Regency, Lampung". JURNAL PEMBELAJARAN DAN BIOLOGI NUKLEUS 9, n.º 1 (1 de marzo de 2023): 10–22. http://dx.doi.org/10.36987/jpbn.v9i1.3853.

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Echinoderms have specific characteristic in the form of spines or protrusions on its body surface. The class of Echinoidea or commonly known as sea urchin is one of the extant members of Echinoderms with ecologically and economic pivotal roles. Habitat of sea urchin is a hard bottom with a mixture of coral reef ecosystems, seagrass beds, and sand and coral debris. In the area of Sari Ringgung Beach, coral reefs and seagrass ecosystems are quite extensive. The purpose of this study was to investigate sea urchin species and analyze its population, relative abundance, diversity index, and dominance index. This research used purposive sampling method based on substrate type criteria. The sea urchin found were identified using the Clark & Rowe (1971) identification book. Two species of sea urchin were found and identified as Diadema sp. and Brissus sp. Individual abundance values ranged from 0-0.027 ind/m2, relative abundance values ranged from 0-96.67%, sea urchin species diversity index was low, ranging from 0-0.5982, and was dominated by sea urchin types of Diadema sp. at station 2 of 0.9356

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Emerson, Chloe E., Helena C. Reinardy, Nicholas R. Bates y Andrea G. Bodnar. "Ocean acidification impacts spine integrity but not regenerative capacity of spines and tube feet in adult sea urchins". Royal Society Open Science 4, n.º 5 (mayo de 2017): 170140. http://dx.doi.org/10.1098/rsos.170140.

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Increasing atmospheric carbon dioxide (CO 2 ) has resulted in a change in seawater chemistry and lowering of pH, referred to as ocean acidification. Understanding how different organisms and processes respond to ocean acidification is vital to predict how marine ecosystems will be altered under future scenarios of continued environmental change. Regenerative processes involving biomineralization in marine calcifiers such as sea urchins are predicted to be especially vulnerable. In this study, the effect of ocean acidification on regeneration of external appendages (spines and tube feet) was investigated in the sea urchin Lytechinus variegatus exposed to ambient (546 µatm), intermediate (1027 µatm) and high (1841 µatm) partial pressure of CO 2 ( p CO 2 ) for eight weeks. The rate of regeneration was maintained in spines and tube feet throughout two periods of amputation and regrowth under conditions of elevated p CO 2 . Increased expression of several biomineralization-related genes indicated molecular compensatory mechanisms; however, the structural integrity of both regenerating and homeostatic spines was compromised in high p CO 2 conditions. Indicators of physiological fitness (righting response, growth rate, coelomocyte concentration and composition) were not affected by increasing p CO 2 , but compromised spine integrity is likely to have negative consequences for defence capabilities and therefore survival of these ecologically and economically important organisms.

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Domenici, P., D. González-Calderón y R. S. Ferrari. "Locomotor performance in the sea urchin Paracentrotus lividus". Journal of the Marine Biological Association of the United Kingdom 83, n.º 2 (20 de marzo de 2003): 285–92. http://dx.doi.org/10.1017/s0025315403007094h.

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The locomotor performance of the Mediterranean sea urchin Paracentrotus lividus was investigated under laboratory conditions. Individuals were placed singly in the centre of a glass surface positioned either horizontally or vertically in tanks with seawater, and their locomotor activity was recorded. For locomotion on a horizontal surface, speed increased with both sea urchin diameter and their straightness of path. Speeds on a vertical surface were size-independent and not related to the straightness of path, although they were affected by vertical path orientation, with the highest speeds occurring for downward movements and the slowest speeds for the upward movements. Taken together, these results suggest that the scaling of sea urchin locomotion may follow similar laws to those of legged animals, for which locomotor performance increases with size on horizontal surface, while their relative cost of locomotion increases with body size on inclined surfaces. It is suggested that differences in horizontal vs vertical locomotion may also be related to differences in the underlying locomotor mechanisms, i.e. using adhesive appendices (tube feet) or levers (spines). In a second experiment, the sea urchin speed obtained during a negative phototactic response to a direct light stimulus was recorded. The results show that speed during light stimulation is higher than that during spontaneous locomotion in sea urchins of intermediate size (2·5–4 cm), suggesting that, in addition to the direction of locomotion as shown by previous studies, light can also have an effect on speed.

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Nakamura, Masaru, Tsuyoshi Uehara y Masatoshi Mita. "Ultrastructural study of endogenous energy substrates in spermatozoa of the four species of the sea urchin, Echinometra mataei". Zygote 8, S1 (diciembre de 1999): S56—S57. http://dx.doi.org/10.1017/s0967199400130278.

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The sea urchin Echinometra mathaei (Blainville) which belongs to the order Echinoida, occurs in abundance on shallow reefs throughout the tropical to warm Indo-Pacific region. Though Okinawan E. mathaei had been considered as a single species showing extensive morphological variation in test shape and spine colour, it was recently shown that the genus Echinomtra consists of four independent species (Uehara & Shingaki, 1984, 1985; Arakaki et al., 1998). However, the scientific names of these four complex species found in Okinawa are still unclear. These Echinometra are tentatively described here as Echinometra sp. A, B, C and D. Echinometra sp. A is characterised by white-tipped spines, a definite bright milled ring and dark skin on the peristome. Echinometra sp. B is characterised by spines with no white tip, with very faded milled rings and dark skin on the peristome. Echinometra sp. D is characterised by spines without a white tip but with a definite bright milled ring and bright skin on the peristome. In the field, these two Echinometra sp. exhibit a richly coloured variation in spines. Echinometra sp. D is characterised by deep black spines with well-defined milled rings and dark skin around the peristome. Only black-spined individuals have been found so far. In addition, these species show different distribution patterns, habitat preference and agonistic behaviour. It has also been shown that these two species are not possible to cross-fertilise under sperm at limiting concentration.

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Moreno-García, Dulce María, Monica Salas-Rojas, Eduardo Fernández-Martínez, Ma del Rocío López-Cuellar, Carolina G. Sosa-Gutierrez, Armando Peláez-Acero, Nallely Rivero-Perez, Adrian Zaragoza-Bastida y Deyanira Ojeda-Ramírez. "Sea urchins: an update on their pharmacological properties". PeerJ 10 (4 de julio de 2022): e13606. http://dx.doi.org/10.7717/peerj.13606.

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Sea urchins are a group of benthic invertebrates characterized by having rigid globose bodies, covered in spines, and have an innate immune system that has allowed them to survive in the environment and defend against many pathogens that affect them. They are consumed for their unique flavor, but also for possessing a rich source of bioactive compounds which make them a source for a wide array of medicinal properties. Thus, these may be used to discover and develop new drugs such as anti-bacterials, anti-carcinogenics and anti-virals. Precisely for those reasons, this revision is centered on the known biological activities in various sea urchin species. Recently, the potential pharmacological benefits of nine sea urchin species [Diadema antillarum (Philippi 1845), Echinometra mathaei (de Blainville), Evechinus chloroticus (Valenciennes), Mesocentrotus nudus (Agassiz, 1863), Paracentrotus lividus (Lamarck, 1816), Scaphechinus mirabilis (Agazzis, 1863), Stomopneustes variolaris (Lamarck, 1816), Tripneustes depressus (Agassiz, 1863), and Tripneustes ventricosus (Lamarck, 1816)] have been evaluated. Our work includes a comprehensive review of the anti-fungal, anti-parasitic, anti-inflammatory, hepatoprotective, anti-viral, anti-diabetic, anti-lipidemic, gastro-protective and anti-cardiotoxic effects. Furthermore, we revised the compounds responsible of these pharmacological effects. This work was intended for a broad readership in the fields of pharmacology, drugs and devices, marine biology and aquaculture, fisheries and fish science. Our results suggest that organic extracts, as well as pure compounds obtained from several parts of sea urchin bodies are effective in vitro and in vivo pharmacological models. As such, these properties manifest the potential use of sea urchins to develop emergent active ingredients.

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Newmeyer, William L. "Management of sea urchin spines in the hand". Journal of Hand Surgery 13, n.º 3 (mayo de 1988): 455–57. http://dx.doi.org/10.1016/s0363-5023(88)80031-5.

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AGUIRRE, L. KAREM, YURI HOOKER, PHILIPPE WILLENZ y EDUARDO HAJDU. "A new Clathria (Demospongiae, Microcionidae) from Peru occurring on rocky substrates as well as epibiontic on Eucidaris thouarsii sea urchins". Zootaxa 3085, n.º 1 (31 de octubre de 2011): 41. http://dx.doi.org/10.11646/zootaxa.3085.1.3.

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Southeastern Pacific sponges (Phylum Porifera) range among the world’s least known faunas, with only 13 species reported to date from the entire Peruvian coast. This state of affairs motivated the onset of two large, cooperative, exploratory initiatives, with the aim of mapping sponge richness and distribution in the area: Proyectos ESPER and EsponjAS. Over 800 specimens have been collected in Peru since 2007, with identifications still in progress. Among these, a sponge species originally thought to be an exclusive epibiont on Eucidaris thouarsii sea urchins, relatively conspicuous on Peru’s Punta Sal region. This sponge, latter found to occur on additional substrates too, is described as a new species of Clathria (Microciona). Cidarid density ranged between 1.5 and 12/m 2 , and largest diameter of the tests between 3.2 and 5.6 cm. Total number of spines on each sea urchin varied between 68 and 96, and percent sponge coverage of these, between 18.2 and 75.7. There appears to be only a slight tendency for increased sponge coverage on larger sea urchins, so there may be factors, other than sea urchin age, shaping this association. Clathria (Microciona) aculeofila sp. nov. can be markedly dominant as an epibiont on E. thouarsii, albeit the great sponge richness in the area. This is in contrast to the allegedly opportunistic, diverse epibiosis by sponges reported previously for Antarctic cidaroids.

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Elkin, David J. y Kay Odashima. "Sea urchin spines detected using point-of-care ultrasonography". Visual Journal of Emergency Medicine 17 (octubre de 2019): 100651. http://dx.doi.org/10.1016/j.visj.2019.100651.

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Burnett, Joseph W. "Bolus ejection: A method for removing sea urchin spines". Annals of Emergency Medicine 39, n.º 1 (enero de 2002): 94–95. http://dx.doi.org/10.1067/mem.2002.120747.

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Falkenberg, Per. "Sea urchin spines as foreign bodies—an alternative treatment". Injury 16, n.º 6 (mayo de 1985): 419–20. http://dx.doi.org/10.1016/0020-1383(85)90062-2.

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25

Brasseur, Lola, Marie Demeyer, Corentin Decroo, Guillaume Caulier, Patrick Flammang, Pascal Gerbaux y Igor Eeckhaut. "Identification and quantification of spinochromes in body compartments of Echinometra mathaei ’s coloured types". Royal Society Open Science 5, n.º 8 (agosto de 2018): 171213. http://dx.doi.org/10.1098/rsos.171213.

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Sea urchin pigmentation is mainly due to polyhydroxy-1,4-naphthoquinones called spinochromes. If their molecular structures are well known in test and spines of many species, their abundance and distribution in other body compartments remain unstudied. The aim of this study is to analyse the pigment composition in four body compartments (test/spines, digestive system, gonads and coelomic fluid) of four coloured types of the sea urchin Echinometra mathaei . Qualitative and quantitative measurements by mass spectrometry highlight the existence of 13 different pigments; among which are five isomers of known spinochromes as well as three potentially new ones. The composition comparison shows the largest spinochrome diversity in ‘test/spines’ body compartments. The spinochrome concentrations vary from 48 to 1279 mg kg −1 of dried body compartment. It is the highest in the digestive system, although it is also important in the organic fraction of the ‘test/spines’ body compartment. This observation may be explained by higher exposures of some body compartments to external environments and by the protective role fulfilled by spinochromes against microorganisms, ultraviolet radiation and reactive oxygen species. The ‘black’ type—the most common coloured type in coral reefs—has the highest concentration of spinochromes indicating their importance in Echinoids' fitness by acting as a protective agent.

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26

Yu, Yaqin, Jingjing Du y Chuanyong Jing. "Remarkable surface-enhanced Raman scattering on self-assembled {201} anatase". Journal of Materials Chemistry C 7, n.º 45 (2019): 14239–44. http://dx.doi.org/10.1039/c9tc05062k.

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The self-assembled sea urchin-like {201} TiO₂ exhibits Raman enhancement factors at 1.6 × 10⁶, ascribed to shape-dependent electromagnetic enhancement with high-density hotspots in the vicinity of sharp tips and at narrow gaps between spines.

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27

Hernandez, Z. M., M. Morales, D. S. Smith y J. del Castillo. "Barium spikes are generated in the spines of the sea urchin Diadema antillarum". Comparative Biochemistry and Physiology Part A: Physiology 86, n.º 2 (enero de 1987): 355–59. http://dx.doi.org/10.1016/0300-9629(87)90342-2.

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28

Merino, Monica, Erika Vicente, Karen N. Gonzales y Fernando G. Torres. "Ageing and degradation determines failure mode on sea urchin spines". Materials Science and Engineering: C 78 (septiembre de 2017): 1086–92. http://dx.doi.org/10.1016/j.msec.2017.04.155.

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29

Fitriyani, Fitriyani, Didik Santoso y Karnan Karnan. "Abundance and Distribution Patterns of Sea Urchins (Echinoidea) at Lakey Beach, Hu'u District, Dompu Regency". Jurnal Biologi Tropis 22, n.º 1 (27 de enero de 2022): 277–88. http://dx.doi.org/10.29303/jbt.v22i1.3119.

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Sea urchins are marine biota that have many benefits for life, so there is a need for information about the existence of sea urchins. The existence of sea urchins in marine ecosystems has a significant influence on the ecological balance, one of which is for coral reefs, because sea urchins are one of the control of macroalgae populations. The purpose of this study was to determine the species abundance, diversity index, dominance index and distribution pattern of sea urchins (Echinoidea) at Lakey Beach, Hu'u District, Dompu Regency. This type of research is descriptive exploratory using purposive sampling method (chosen method) in determining the three research stations. The data obtained were analyzed using the species formula, the Shanon Wienner diversity index, the Simpson dominance index, and the Morisita index. The results showed that the highest species on the Lakey Coast were Echinometra mathei with values of 0.60 Ind/mÃÂ² and Echinometra viridis with values of 0.45 Ind/mÃÂ². The diversity index of sea urchins at Lakey Beach is included in the moderate criteria with a species diversity index value of H'=1.03. The sea urchin dominance index in Lakey Beach is included in the low criteria with a species dominance index of 0.42. The distribution pattern of sea urchins on Lakey Beach includes two criteria, namely flocking and uniform. Types of sea urchins that belong to a grouped distribution pattern are Echinometra mathei and Echinometra viridis. While the types of sea urchins that have a uniform distribution pattern are Diadema setosum, Echinotrix calamaris (brown striped spines), Mespilia globulus, and Tripneustus gratilia. This research can be used as a reference and source of information to see the condition of the ecosystem in Lakey Beach, Hu'u District, Dompu Regency. So that the community and can preserve marine life such as sea urchins (Echinoidea) so that their lives can be maintained.

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30

LaVigne, M., T. M. Hill, E. Sanford, B. Gaylord, A. D. Russell, E. A. Lenz, J. D. Hosfelt y M. K. Young. "Effects of increased pCO2 and geographic origin on purple sea urchin (Strongylocentrotus purpuratus) calcite elemental composition". Biogeosciences Discussions 9, n.º 12 (13 de diciembre de 2012): 17939–73. http://dx.doi.org/10.5194/bgd-9-17939-2012.

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Abstract. Ocean acidification will likely have negative impacts on invertebrates producing skeletons composed of calcium carbonate. Skeletal solubility is partly controlled by the incorporation of "foreign" ions (such as Mg and Sr) into the crystal lattice of these skeletal structures, a process that is sensitive to a variety of biological and environmental factors. Here we explore the effects of life stage, oceanographic region of origin, and changes in the partial pressure of carbon dioxide in seawater (pCO2) on trace elemental composition in the purple sea urchin (Strongylocentrotus purpuratus). We show that, similar to other urchin taxa, adult purple sea urchins have the ability to precipitate skeleton composed of a range of biominerals spanning low to high magnesium calcites. Mg/Ca and Sr/Ca ratios were substantially lower in adult spines compared to adult tests. On the other hand, trace elemental composition was invariant among adults collected from four oceanographically distinct regions along the US west coast (Oregon, Northern California, Central California, and Southern California). Skeletons of newly settled juvenile urchins that originated from adults from the four regions exhibited intermediate Mg/Ca and Sr/Ca between adult spine and test endmembers, indicating that skeleton precipitated during early life stages is more soluble than adult spines and less soluble than adult tests. Mean skeletal Mg/Ca or Sr/Ca of juvenile skeleton did not vary with source region when larvae were reared under present-day, global-average seawater carbonate conditions (400 ppm; pH = 8.02 ± 0.03 1 SD; Ωcalcite = 3.3 ± 0.2 1 SD). However, when reared under elevated CO2 (900 ppm; pH = 7.72 ± 0.03; Ωcalcite = 1.8 ± 0.1), skeletal Sr/Ca in juveniles exhibited increased variance across the four regions. Although larvae from the northern populations (Oregon, Northern California, Central California) did not exhibit differences in Mg or Sr incorporation under elevated CO2 (Sr/Ca = 2.09 ± 0.06 mmol mol−1; Mg/Ca = 66.9 ± 4.1 mmol mol−1), juveniles of Southern California origin partitioned ∼ 8% more Sr into their skeletons when exposed to higher CO2 (Sr/Ca = 2.26 ± 0.05 vs. 2.10 ± 0.03 mmol mol−1 1 SD). Together these results suggest that the diversity of carbonate minerologies present across different skeletal structures and life stages in purple sea urchins does not translate into an equivalent plasticity of response associated with geographic variation or temporal shifts in seawater properties. Rather, composition of S. purpuratus skeleton precipitated during both early and adult life history stages appears relatively robust to spatial gradients and predicted changes in seawater carbonate chemistry for 2100. An exception to this trend may arise during early life stages, where certain populations of purple sea urchins may alter skeletal mineral precipitation rates and composition beyond a given CO2 threshold. The degree to which this latter geochemical plasticity might affect mineral stability and solubility in a future, altered ocean requires additional study.

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31

Kinjo, Sonoko, Tsuyoshi Uehara, Ikuko Yazaki, Yoshihisa Shirayama y Hiroshi Wada. "Morphological diversity of larval skeletons in the sea urchin family Echinometridae (Echinoidea: Echinodermata)". Journal of the Marine Biological Association of the United Kingdom 86, n.º 4 (15 de junio de 2006): 799–816. http://dx.doi.org/10.1017/s0025315406013725.

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To clarify the morphological variety of larval skeletons, a detailed morphological comparison among the species of the family Echinometridae was performed. Through conspecific comparison of larval skeletons among different ages, we found five skeletal characters of the body skeleton that are stable in the four-armed pluteus and thus useful in homologous comparison among the species. The morphological variation was summarized as the difference in the number of spines and posteroventral transverse rods, and differences in the shape of the body skeleton. Significant correlations were found between some skeletal characters, such as between upper body length and bottom width of body skeleton and between lower body length and the number of spines. We found that the larval skeletons of tropical species tend to have fewer spines and rods than those of temperate species, which is consistent with the hypothesis that a reduction in skeletal elements decreases the specific gravity of larvae as an adaptation to tropical waters.

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32

Zhang, Yuzhe, Shiqiang Chai, Yurong Ma y Limin Qi. "Investigations on the microstructures of sea urchin spines via selective dissolution". CrystEngComm 18, n.º 48 (2016): 9374–81. http://dx.doi.org/10.1039/c6ce02074g.

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33

Toader, Nicu, Werner Sobek y Klaus G. Nickel. "Energy absorption in functionally graded concrete bioinspired by sea urchin spines". Journal of Bionic Engineering 14, n.º 2 (junio de 2017): 369–78. http://dx.doi.org/10.1016/s1672-6529(16)60405-5.

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34

Boer, A., F. R. Ochsendorf, C. Beier y R. Kaufmann. "Effective removal of sea-urchin spines by erbium: YAG laser ablation". British Journal of Dermatology 145, n.º 1 (julio de 2001): 169–70. http://dx.doi.org/10.1046/j.1365-2133.2001.04306.x.

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35

Peters, Brian H. "The innervation of spines in the sea-urchin Echinus esculentus L." Cell and Tissue Research 239, n.º 1 (enero de 1985): 219–28. http://dx.doi.org/10.1007/bf00214922.

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36

Presser, V., S. Schultheiß, C. Berthold y K. G. Nickel. "Sea urchin spines as a model-system for permeable, light-weight ceramics with graceful failure behavior. Part I. Mechanical behavior of sea urchin spines under compression". Journal of Bionic Engineering 6, n.º 3 (septiembre de 2009): 203–13. http://dx.doi.org/10.1016/s1672-6529(08)60125-0.

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37

Federico, Serena, Francesca Glaviano, Roberta Esposito, Enea Tentoni, Pasquale Santoro, Davide Caramiello, Maria Costantini y Valerio Zupo. "The “Bald Disease” of the Sea Urchin Paracentrotus lividus: Pathogenicity, Molecular Identification of the Causative Agent and Therapeutic Approach". Microorganisms 11, n.º 3 (16 de marzo de 2023): 763. http://dx.doi.org/10.3390/microorganisms11030763.

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In recent decades, various species of Mediterranean sea urchins, including Paracentrotus lividus, have been subject to widespread seasonal episodes of mass mortality whose causative agents are still unclear. In particular, P. lividus is subject to late winter events of mortality, due to a disease manifested by a massive loss of spines and the presence of greenish amorphous material on the tests (i.e., the sea urchin skeleton consisting of spongeous calcite). Documented mortality events show a seasonal epidemic diffusion and might produce economic losses also in aquaculture facilities, besides the environmental constraints to its diffusion. We collected individuals showing conspicuous lesions on the body surface and reared them in recirculated aquaria. Samples of external mucous were collected along with coelomic liquids and cultured to isolate bacterial and fungal strains, further submitted to molecular identification through the amplification of prokaryotic 16S rDNA. In addition, pools of infected sea urchins were reared in recirculated tanks after short baths in a formulated therapeutic compound and their survival rates were compared to non-treated individuals for variable periods. Here, we aimed at a redescription of the etiopathogenetic nature of the parasites and tested the efficacy of a possible treatment, to be proposed for aquaculture purposes.

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38

LaVigne, M., T. M. Hill, E. Sanford, B. Gaylord, A. D. Russell, E. A. Lenz, J. D. Hosfelt y M. K. Young. "The elemental composition of purple sea urchin (Strongylocentrotus purpuratus) calcite and potential effects of pCO2 during early life stages". Biogeosciences 10, n.º 6 (1 de junio de 2013): 3465–77. http://dx.doi.org/10.5194/bg-10-3465-2013.

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Abstract. Ocean acidification will likely have negative impacts on invertebrates producing skeletons composed of calcium carbonate. Skeletal solubility is partly controlled by the incorporation of "foreign" ions (e.g. magnesium) into the crystal lattice of these skeletal structures, a process that is sensitive to a variety of biological and environmental factors. Here we explore effects of life stage, oceanographic region of origin, and changes in the partial pressure of carbon dioxide in seawater (pCO2) on trace elemental composition in the purple sea urchin (Strongylocentrotus purpuratus). We show that, similar to other urchin taxa, adult purple sea urchins have the ability to precipitate skeleton composed of a range of biominerals spanning low- to high-Mg calcites. Mg / Ca and Sr / Ca ratios were substantially lower in adult spines compared to adult tests. On the other hand, trace elemental composition was invariant among adults collected from four oceanographically distinct regions spanning a range of carbonate chemistry conditions (Oregon, Northern California, Central California, and Southern California). Skeletons of newly settled juvenile urchins that originated from adults from the four regions exhibited intermediate Mg / Ca and Sr / Ca between adult spine and test endmembers, indicating that skeleton precipitated during early life stages is more soluble than adult spines and less soluble than adult tests. Mean skeletal Mg / Ca or Sr / Ca of juvenile skeleton did not vary with source region when larvae were reared under present-day, global-average seawater carbonate conditions (400 μatm; pHT = 8.02 ± 0.03 1 SD; Ωcalcite = 3.3 ± 0.2 1 SD). However, when reared under elevated pCO2 (900 μatm; pHT = 7.73 ± 0.03; Ωcalcite = 1.8 ± 0.1), skeletal Sr / Ca in juveniles exhibited increased variance across the four regions. Although larvae from the northern populations (Oregon, Northern California, Central California) did not exhibit differences in Mg or Sr incorporation under elevated pCO2 (Sr / Ca = 2.10 ± 0.06 mmol mol−1; Mg / Ca = 67.4 ± 3.9 mmol mol−1), juveniles of Southern California origin partitioned ~8% more Sr into their skeletons when exposed to higher pCO2 (Sr / Ca = 2.26 ± 0.08 vs. 2.09 ± 0.005 mmol mol−1 1 SD). Together these results suggest that the diversity of carbonate minerologies present across different skeletal structures and life stages in purple sea urchins does not translate into an equivalent geochemical plasticity of response associated with geographic variation or temporal shifts in seawater properties. Rather, composition of S. purpuratus skeleton precipitated during both early and adult life history stages appears relatively robust to spatial gradients and predicted future changes in carbonate chemistry. An exception to this trend may arise during early life stages, where certain populations of purple sea urchins may alter skeletal mineral precipitation rates and composition beyond a given pCO2 threshold. This potential for geochemical plasticity during early development in contrast to adult stage geochemical resilience adds to the growing body of evidence that ocean acidification can have differing effects across organismal life stages.

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39

Salvatore, Ciaravolo, Cirino, Toscano, Salvatore, Gallo, Naviglio y Andolfi. "Fatty Acids from Paracentrotus lividus Sea Urchin Shells Obtained via Rapid Solid Liquid Dynamic Extraction (RSLDE)". Separations 6, n.º 4 (22 de octubre de 2019): 50. http://dx.doi.org/10.3390/separations6040050.

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Sea urchins (Echinodermata, Echinoidea) are good a source of bioactive compounds belonging to different classes of natural substances. The edible Mediterranean sea urchin Paracentrotus lividus is a renowned animal model for study in different fields of biology, but it is intensively harvested for high commercial value due to the delicacy of its gonads. Most studies have focused on the composition and the nutritional value of P. lividus gonads (the edible part), but little interest has been taken in the other body parts, such as the shells and spines, which are generally considered waste material. The purpose of this study was to obtain an extract from sea urchin shells, with a green methodology of extraction, and to characterize the lipophilic components for potential applications. The shells of P. lividus were extracted via a very well performing technology based on rapid solid liquid dynamic extraction (RSLDE) implemented via an automated device (Naviglio Extractor®). The obtained extract shows the presence of fatty acids and their esters (methyl, ethyl and 1-glycerol esters). Gas chromatography-mass spectrometry (GC-MS) measurements were used to determine fatty acid abundance in the chromatographic fractions of the extract. Arachidonic acid (ARA), 5,8,11,14,17-eicosapentanoic acid (EPA), and 11-eicosenoic acids and their esters are the most abundant components. The presence of many polyunsaturated fatty acids (PUFA) in the extract, even in low percentages allows a future application in nutrition or medical use.

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40

JACINTO, DAVID y TERESA CRUZ. "Paracentrotus lividus (Echinodermata: Echinoidea) attachment force and burrowing behavior in rocky shores of SW Portugal*". Zoosymposia 7, n.º 1 (12 de diciembre de 2012): 231–40. http://dx.doi.org/10.11646/zoosymposia.7.1.21.

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The rock burrowing sea urchin Paracentrotus lividus is a common wave-swept organism that inhabits intertidal rock pools and shallow subtidal temperate shores. Here we present field data on P. lividus attachment force, burrow shape and test diameter measured in different rocky habitats (intertidal pools, low shore intertidal channels and shallow subtidal shores) and in two study sites with different wave-exposure conditions. These data were then analyzed to look for a possible relationship between the size of sea urchins and their attachment force and burrow shape as well as the influence of wave-exposure and habitat in the measured variables. P. lividus test diameter varied among habitats: urchins were smaller in mid-shore intertidal pools and bigger in shallow subtidal shores. We observed in all studied habitats that attachment force was not correlated with test size, while burrow shape index (BSI) was negatively correlated with test size. Results suggest that the attachment force of large and small urchins was similar, but smaller animals occurred in relatively deeper burrows (higher BSI values). Attachment force was positively correlated with BSI, which indicates that burrows may enhance attachment force of P. lividus living in rocky shores by allowing the use of spines as anchorage points and reducing the urchin area exposed to drag forces. Our results partially support the hypothesis that attachment force and BSI might be influenced by local variation in wave-exposure. Higher values for both attachment strength and BSI were measured in intertidal rock pools, the most wave-exposed habitat considered in this study, suggesting that urchins living in such habitat are more able to resist dislodgment by wave-induced forces since they occupy relatively deeper burrows and thusattach more firmly to the substrate. However, neither attachment force nor BSI were higher in the more exposed shore.

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41

Emlet, Richard B. "What is a juvenile sea urchin? A comparative and phylogenetic survey of post-metamorphic juveniles". Zygote 8, S1 (diciembre de 1999): S44—S45. http://dx.doi.org/10.1017/s0967199400130217.

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Echinoid development progresses through embryonic and larval stages to metamorphosis and the adult form. Despite vast differences in embryos and larval forms, including bilaterally symmetric echinopluteus larvae, ovoid non-feeding larvae and brooded embryos, all metamorphose into juvenile sea urchins with pentaradial symmetry. The adult sea urchin body plan is initiated as the juvenile rudiment. The rudiment has been called the phylotypic stage for the class Echinoidea, a designation that implies little variation at this midpoint in development (e.g. Raff et al., 1991; Richardson, 1995; Raff, 1996). However, right at metamorphosis (upon eversion of the juvenile rudiment), variations in test symmetry, shape and number of spines, and number of skeletal plates, podia and pedicellariae are present in juveniles. This variation suggests either that there is no phylotypic stage or that such a stage occurs earlier in rudiment formation. To distinguish between these possibilities, I explored the patterns by which the juvenile rudiment is formed as well as the variation among juveniles approximately 1 day after metamorphosis in 19 echinoid taxa covering a broad taxonomic range including cidaroids, diadematids, irregular echinoids (spatangoids and clypeasteroids), arbaciids, temnopleurids, echinometrids and strongylocentrotids. Most of the material for analysis of juveniles was obtained by the author. Additional information was gathered from classical studies of metamorphosis. Data were collected on the number and shape of dorsal pedicellariae, juvenile and adult spines, primary and secondary podia, and juvenile test shape. When possible multiple individuals within a species were examined, revealing no or only minor trait variation. These data were mapped on a well-resolved phylogeny established from adult characters.

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42

Klang, Katharina y Klaus G. Nickel. "The Plant-Like Structure of Lance Sea Urchin Spines as Biomimetic Concept Generator for Freeze-Casted Structural Graded Ceramics". Biomimetics 6, n.º 2 (31 de mayo de 2021): 36. http://dx.doi.org/10.3390/biomimetics6020036.

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The spine of the lance sea urchin (Phyllacanthus imperialis) is an unusual plant-akin hierarchical lightweight construction with several gradation features: a basic core–shell structure is modified in terms of porosities, pore orientation and pore size, forming superstructures. Differing local strength and energy consumption features create a biomimetic potential for the construction of porous ceramics with predetermined breaking points and adaptable behavior in compression overload. We present a new detailed structural and failure analysis of those spines and demonstrate that it is possible to include at least a limited number of those features in an abstracted way in ceramics, manufactured by freeze-casting. This possibility is shown to come from a modified mold design and optimized suspensions.

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43

Sjøberg, Thomas y Louis De Weerd. "The usefulness of a skin biopsy punch to remove sea urchin spines". ANZ Journal of Surgery 80, n.º 5 (21 de enero de 2010): 383. http://dx.doi.org/10.1111/j.1445-2197.2010.05296.x.

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44

Gungor, Sule, Nagehan Tarikçi y Gonca Gokdemir. "Removal of Sea Urchin Spines Using Erbıum-Doped Yttrium Aluminum Garnet Ablatıon". Dermatologic Surgery 38, n.º 3 (marzo de 2012): 508–10. http://dx.doi.org/10.1111/j.1524-4725.2011.02259.x.

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45

Hamil, Somia, Mounia Baha, Azzedine Abdi, Malika Alili, Behlul Koc Bilican, Bahar Akyuz Yilmaz, Yavuz Selim Cakmak, Ismail Bilican y Murat Kaya. "Use of sea urchin spines with chitosan gel for biodegradable film production". International Journal of Biological Macromolecules 152 (junio de 2020): 102–8. http://dx.doi.org/10.1016/j.ijbiomac.2020.02.263.

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46

Veis, Arthur. "Organic Matrix-related mineralization of sea urchin spicules, spines, test and teeth". Frontiers in Bioscience 16, n.º 1 (2011): 2540. http://dx.doi.org/10.2741/3871.

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47

Loi, Barbara, Ivan Guala, Rodrigo Pires da Silva, Gianni Brundu, Maura Baroli y Simone Farina. "Hard time to be parents? Sea urchin fishery shifts potential reproductive contribution of population onto the shoulders of the young adults". PeerJ 5 (8 de marzo de 2017): e3067. http://dx.doi.org/10.7717/peerj.3067.

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BackgroundIn Sardinia, as in other regions of the Mediterranean Sea, sustainable fisheries of the sea urchinParacentrotus lividushave become a necessity. At harvesting sites, the systematic removal of large individuals (diameter ≥ 50 mm) seriously compromises the biological and ecological functions of sea urchin populations. Specifically, in this study, we compared the reproductive potential of the populations from Mediterranean coastal areas which have different levels of sea urchin fishing pressure. The areas were located at Su Pallosu Bay, where pressure is high and Tavolara-Punta Coda Cavallo, a marine protected area where sea urchin harvesting is low.MethodsReproductive potential was estimated by calculating the gonadosomatic index (GSI) from June 2013 to May 2014 both for individuals of commercial size (diameter without spines, TD ≥ 50 mm) and the undersized ones with gonads (30 ≤ TD < 40 mm and 40 ≤ TD < 50 mm). Gamete output was calculated for the commercial-size class and the undersized individuals with fertile gonads (40 ≤ TD < 50 mm) in relation to their natural density (gamete output per m2).ResultsThe reproductive potential of populations was slightly different at the beginning of the sampling period but it progressed at different rates with an early spring spawning event in the high-pressure zone and two gamete depositions in early and late spring in the low-pressure zone. For each fertile size class, GSI values changed significantly during the year of our study and between the two zones. Although the multiple spawning events determined a two-fold higher total gamete output of population (popTGO) in the low-pressure zone, the population mean gamete output (popMGO) was similar in the two zones. In the high-pressure zone, the commercial-sized individuals represented approximatively 5% of the population, with almost all the individuals smaller than 60 mm producing an amount of gametes nearly three times lower than the undersized ones. Conversely, the high density of the undersized individuals released a similar amount of gametes to the commercial-size class in the low-pressure zone.DiscussionOverall, the lack of the commercial-size class in the high-pressure zone does not seem to be very alarming for the self-supporting capacity of the population, and the reproductive potential contribution seems to depend more on the total density of fertile sea urchins than on their size. However, since population survival in the high-pressure zone is supported by the high density of undersized sea urchins between 30 and 50 mm, management measures should be addressed to maintain these sizes and to shed light on the source of the larval supply.

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48

Wittmann, Karl J. "Description of Idiomysis diadema sp. nov. (Mysida, Mysidae, Anisomysini), associated with Diadema urchins in the Red Sea; with nomenclatorial notes on its genus". Crustaceana 89, n.º 5 (2016): 611–23. http://dx.doi.org/10.1163/15685403-00003542.

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The mysid Idiomysis diadema sp. nov. is described from small swarms hovering between the spines of the sea urchin Diadema setosum (Leske, 1778) at the reef flat of Dahab, Red Sea. The most striking characters within its genus are the subdivided antennal scale, endopod of uropods longer than exopod, and a pair of minute spines on the terminal margin of the telson. With this first description, a total of six Idiomysis species are now known, two of which are associated with cnidarians and only the new one with echinoids. An updated definition is given for the genus Idiomysis W. M. Tattersall, 1922, in order to match the current species inventory. To avoid previously incorrect and ambivalent gender attribution, I propose using the feminine gender for this genus throughout. Consequently, the spelling of two of its taxa, I. mozambica Deprez, Wooldridge & Mees, 2001, and I. robusta Connell, 2008, is changed.

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49

Gómez Vázquez, Nayeli Sarahi, Priscy Alfredo Luque Morales, Claudia Mariana Gomez Gutierrez, Osvaldo de Jesus Nava Olivas, Ruben Cesar Villarreal Sánchez, Alfredo Rafael Vilchis Nestor y Manuel de Jesús Chinchillas Chinchillas. "Hydroxyapatite Biosynthesis Obtained from Sea Urchin Spines (Strongylocentrotus purpuratus): Effect of Synthesis Temperature". Processes 8, n.º 4 (22 de abril de 2020): 486. http://dx.doi.org/10.3390/pr8040486.

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In this investigation, hydroxyapatite (HA) was synthesized using sea urchin spines (Strongylocentrotus purpuratus) via a precipitation and heat treatment method at three different temperatures (500, 600 and 700 °C). Biosynthesized HA was characterized to determine the vibration of functional groups, morphology, particle size, crystalline structure and chemical composition. For this, Fourier-Transform Infrared Spectroscopy with Attenuated Total Reflectance (FTIR-ATR), Scanning Electron Microscopy (SEM) coupled with Energy Dispersive X-ray Spectroscopy (EDS), X-ray Diffraction (XRD) and X-ray Photoelectron Spectroscopy (XPS) were used, respectively. The FTIR-ATR results reveal that the most defined characteristic HA bonds (O-H, P-O and C-O bonds) were better defined at higher synthesis temperatures. SEM also presented evidence that temperature has a significant effect on morphology. EDS results showed that the Ca/P ratio increased in the samples at higher temperatures. XRD analysis presented the characteristic peaks of HA, showing a lower crystallinity when the synthesis temperature increased. Finally, the XPS confirmed that the material resulting from biosynthesis was HA. Hence, according to these results, the synthesis temperature of HA has a significant effect on the characteristics of the resulting material.

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Short, Jack H. y Daryl J. Sulit. "Sea urchin spines in the stratum corneum: an early finding related to trauma". Journal of Cutaneous Pathology 41, n.º 3 (17 de diciembre de 2013): 322–25. http://dx.doi.org/10.1111/cup.12257.

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