Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Science ; 382(6669): 358, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37883570

RESUMO

By adding coral genes to a nonmineralizing relative, team aims to show how reefs are built.


Assuntos
Antozoários , Engenharia Genética , Anêmonas-do-Mar , Animais , Antozoários/genética , Recifes de Corais , Engenharia Genética/métodos , Anêmonas-do-Mar/genética
2.
J Hered ; 111(5): 471-485, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32803261

RESUMO

Deep-sea habitats may drive unique dispersal and demographic patterns for fishes, but population genetic analyses to address these questions have rarely been conducted for fishes in these environments. This study investigates the population structure of 3 tropical deepwater snappers of the genus Etelis that reside at 100-400 m depth, with broad and overlapping distributions in the Indo-Pacific. Previous studies showed little population structure within the Hawaiian Archipelago for 2 of these species: Etelis coruscans and E. carbunculus. Here we extend sampling to the entire geographic range of each species to resolve the population genetic architecture for these 2 species, as well as a recently exposed cryptic species (Etelis sp.). One goal was to determine whether deepwater snappers are more dispersive than shallow-water fishes. A second goal was to determine whether submesophotic fishes have older, more stable populations than shallow reef denizens that are subject to glacial sea-level fluctuations. Both goals are pertinent to the management of these valuable food fishes. A total of 1153 specimens of E. coruscans from 15 geographic regions were analyzed, along with 1064 specimens of E. carbunculus from 11 regions, and 590 specimens of E. sp. from 16 regions. The first 2 species were analyzed with mtDNA and 9-11 microsatellite loci, while E. sp. was analyzed with mtDNA only. Etelis coruscans had a non-significant microsatellite global FST, but significant global mtDNA Ф ST = 0.010 (P = 0.0007), with the isolation of Seychelles in the western Indian Ocean, and intermittent signals of isolation for the Hawaiian Archipelago. Etelis carbunculus had a non-significant microsatellite global FST, and significant global mtDNA Ф ST = 0.021 (P = 0.0001), with low but significant levels of isolation for Hawai'i, and divergence between Tonga and Fiji. Etelis sp. had mtDNA Ф ST = 0.018 (P = 0.0005), with a strong pattern of isolation for both Seychelles and Tonga. Overall, we observed low population structure, shallow mtDNA coalescence (similar to near-shore species), and isolation at the fringes of the Indo-Pacific basin in Hawai'i and the western Indian Ocean. While most shallow-water species have population structure on the scale of biogeographic provinces, deepwater snapper populations are structured on the wider scale of ocean basins, more similar to pelagic fishes than to shallow-water species. This population structure indicates the capacity for widespread dispersal throughout the Indo-Pacific region.


Assuntos
Peixes/classificação , Peixes/genética , Genética Populacional , Animais , DNA Mitocondrial , Técnicas de Genotipagem , Oceano Índico , Repetições de Microssatélites , Oceano Pacífico , Variantes Farmacogenômicos , Filogenia
3.
Science ; 366(6472): 1433, 2019 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-31857461
4.
J Hered ; 109(2): 162-175, 2018 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-28637254

RESUMO

The lionfish is an iconic marine fish, and recently renowned for a disastrous introduction into the West Atlantic. Genetic surveys of the putative invaders (Pterois volitans and Pterois miles) in their natural Indo-Pacific range can illuminate both topics. Previous research indicated that P. volitans and P. miles are sister species that hybridize in the invasive range, but hybridization in the native range is unknown. Here, we apply mtDNA COI and 2 nuclear introns (S7 RP1 and Gpd2) from 229 lionfish including the 2 invaders and 2 closely-related taxa (44 P. miles, 91 P. volitans, 31 Pterois lunulata, and 63 Pterois russelii) from 10 locations in their native ranges. Genetic data are supplemented with key morphological characters: dorsal, anal, and pectoral fin ray counts. We observed 2 lineages (d = 4.07%, 0.89%, and 2.75% at COI, S7 RP1, and Gpd2, respectively) among the 4 putative species: an Indian Ocean lineage represented by P. miles, and a Pacific Ocean lineage represented by P. lunulata and P. russelii. All specimens of the invasive P. volitans appear to be hybrids between the Indian Ocean P. miles and a Pacific lineage encompassing P. lunulata/russelii, a conclusion supported by both genetics and morphology. The divergences between Indian and Pacific forms are within the range of species-level partitions in fishes, and we recommend retention of the names P. miles and P. russelii for Indian and Pacific forms. The hybrid origin of the Atlantic invasion invokes the possibility of heterosis as a contributing factor to invasion success.


Assuntos
Peixes/genética , Hibridização Genética , Espécies Introduzidas , Animais , DNA Mitocondrial , Peixes/classificação , Vigor Híbrido , Íntrons , Filogeografia , Especificidade da Espécie
5.
Toxins (Basel) ; 9(7)2017 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-28686221

RESUMO

Lion's mane jellyfish (Cyanea capillata) stings cause severe pain and can lead to dangerous systemic effects, including Irukandji-like syndrome. As is the case for most cnidarian stings, recommended medical protocols in response to such stings lack rigorous scientific support. In this study, we sought to evaluate potential first aid care protocols using previously described envenomation models that allow for direct measurements of venom activity. We found that seawater rinsing, the most commonly recommended method of tentacle removal for this species, induced significant increases in venom delivery, while rinsing with vinegar or Sting No More® Spray did not. Post-sting temperature treatments affected sting severity, with 40 min of hot-pack treatment reducing lysis of sheep's blood (in agar plates), a direct representation of venom load, by over 90%. Ice pack treatment had no effect on sting severity. These results indicate that sting management protocols for Cyanea need to be revised immediately to discontinue rinsing with seawater and include the use of heat treatment.


Assuntos
Mordeduras e Picadas/terapia , Venenos de Cnidários/toxicidade , Cifozoários , Ácido Acético/uso terapêutico , Animais , Eritrócitos , Primeiros Socorros , Hemólise , Temperatura Alta/uso terapêutico , Gelo , Água do Mar , Ovinos , Urina
6.
Toxins (Basel) ; 9(5)2017 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-28445412

RESUMO

Stings from the hydrozoan species in the genus Physalia cause intense, immediate skin pain and elicit serious systemic effects. There has been much scientific debate about the most appropriate first aid for these stings, particularly with regard to whether vinegar use is appropriate (most current recommendations recommend against vinegar). We found that only a small percentage (≤1.0%) of tentacle cnidae discharge during a sting event using an ex vivo tissue model which elicits spontaneous stinging from live cnidarian tentacles. We then tested a variety of rinse solutions on both Atlantic and Pacific Physalia species to determine if they elicit cnidae discharge, further investigating any that did not cause immediate significant discharge to determine if they are able to inhibit cnidae discharge in response to chemical and physical stimuli. We found commercially available vinegars, as well as the recently developed Sting No More® Spray, were the most effective rinse solutions, as they irreversibly inhibited cnidae discharge. However, even slight dilution of vinegar reduced its protective effects. Alcohols and folk remedies, such as urine, baking soda and shaving cream, caused varying amounts of immediate cnidae discharge and failed to inhibit further discharge, and thus likely worsen stings.


Assuntos
Mordeduras e Picadas/terapia , Venenos de Cnidários/efeitos adversos , Primeiros Socorros/métodos , Hidrozoários , Ácido Acético/uso terapêutico , Animais , Eritrócitos , Etanol/uso terapêutico , Hemólise , Humanos , Sefarose , Bicarbonato de Sódio/uso terapêutico , Soluções , Resultado do Tratamento , Urina
7.
Toxins (Basel) ; 9(3)2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28294982

RESUMO

Cnidarian envenomations are the leading cause of severe and lethal human sting injuries from marine life. The total amount of venom discharged into sting-site tissues, sometimes referred to as "venom load", has been previously shown to correlate with tentacle contact length and sequelae severity. Since <1% of cnidae discharge upon initial tentacle contact, effective and safe removal of adherent tentacles is of paramount importance in the management of life-threatening cubozoan stings. We evaluated whether common rinse solutions or scraping increased venom load as measured in a direct functional assay of venom activity (hemolysis). Scraping significantly increased hemolysis by increasing cnidae discharge. For Alatina alata, increases did not occur if the tentacles were first doused with vinegar or if heat was applied. However, in Chironex fleckeri, vinegar dousing and heat treatment were less effective, and the best outcomes occurred with the use of venom-inhibiting technologies (Sting No More® products). Seawater rinsing, considered a "no-harm" alternative, significantly increased venom load. The application of ice severely exacerbated A. alata stings, but had a less pronounced effect on C. fleckeri stings, while heat application markedly reduced hemolysis for both species. Our results do not support scraping or seawater rinsing to remove adherent tentacles.


Assuntos
Mordeduras e Picadas/terapia , Cubomedusas , Primeiros Socorros/métodos , Animais , Venenos de Cnidários , Gelo , Água do Mar , Pele , Suínos
9.
Toxins (Basel) ; 8(4): 97, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-27043628

RESUMO

Cnidarian envenomations are an important public health problem, responsible for more deaths than shark attacks annually. For this reason, optimization of first-aid care is essential. According to the published literature, cnidarian venoms and toxins are heat labile at temperatures safe for human application, which supports the use of hot-water immersion of the sting area(s). However, ice packs are often recommended and used by emergency personnel. After conducting a systematic review of the evidence for the use of heat or ice in the treatment of cnidarian envenomations, we conclude that the majority of studies to date support the use of hot-water immersion for pain relief and improved health outcomes.


Assuntos
Mordeduras e Picadas/terapia , Venenos de Cnidários/toxicidade , Crioterapia , Temperatura Alta/uso terapêutico , Animais , Cnidários , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Toxins (Basel) ; 8(1)2016 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-26761033

RESUMO

Despite the medical urgency presented by cubozoan envenomations, ineffective and contradictory first-aid management recommendations persist. A critical barrier to progress has been the lack of readily available and reproducible envenomation assays that (1) recapitulate live-tentacle stings; (2) allow quantitation and imaging of cnidae discharge; (3) allow primary quantitation of venom toxicity; and (4) employ rigorous controls. We report the implementation of an integrated array of three experimental approaches designed to meet the above-stated criteria. Mechanistically overlapping, yet distinct, the three approaches comprised (1) direct application of test solutions on live tentacles (termed tentacle solution assay, or TSA) with single image- and video-microscopy; (2) spontaneous stinging assay using freshly excised tentacles overlaid on substrate of live human red blood cells suspended in agarose (tentacle blood agarose assays, or TBAA); and (3) a "skin" covered adaptation of TBAA (tentacle skin blood agarose assay, or TSBAA). We report the use and results of these assays to evaluate the efficacy of topical first-aid approaches to inhibit tentacle firing and venom activity. TSA results included the potent stimulation of massive cnidae discharge by alcohols but only moderate induction by urine, freshwater, and "cola" (carbonated soft drink). Although vinegar, the 40-year field standard of first aid for the removal of adherent tentacles, completely inhibited cnidae firing in TSA and TSBAA ex vivo models, the most striking inhibition of both tentacle firing and subsequent venom-induced hemolysis was observed using newly-developed proprietary formulations (Sting No More™) containing copper gluconate, magnesium sulfate, and urea.


Assuntos
Ácido Acético/uso terapêutico , Mordeduras e Picadas/tratamento farmacológico , Venenos de Cnidários/toxicidade , Cubomedusas , Ácido Acético/farmacologia , Administração Tópica , Animais , Bioensaio , Eritrócitos/efeitos dos fármacos , Primeiros Socorros , Hemólise/efeitos dos fármacos , Humanos , Nematocisto/efeitos dos fármacos
11.
PLoS One ; 9(4): e91665, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24722193

RESUMO

The Hawaiian Archipelago has become a natural laboratory for understanding genetic connectivity in marine organisms as a result of the large number of population genetics studies that have been conducted across this island chain for a wide taxonomic range of organisms. However, population genetic studies have been conducted for only two species occurring in the mesophotic or submesophotic zones (30+m) in this archipelago. To gain a greater understanding of genetic connectivity in these deepwater habitats, we investigated the genetic structure of two submesophotic fish species (occurring ∼200-360 m) in this archipelago. We surveyed 16 locations across the archipelago for submesophotic snappers Etelis coruscans (N = 787) and E. "marshi" (formerly E. carbunculus; N = 770) with 436-490 bp of mtDNA cytochrome b and 10-11 microsatellite loci. Phylogeographic analyses reveal no geographic structuring of mtDNA lineages and recent coalescence times that are typical of shallow reef fauna. Population genetic analyses reveal no overall structure across most of the archipelago, a pattern also typical of dispersive shallow fishes. However some sites in the mid-archipelago (Raita Bank to French Frigate Shoals) had significant population differentiation. This pattern of no structure between ends of the Hawaiian range, and significant structure in the middle, was previously observed in a submesophotic snapper (Pristipomoides filamentosus) and a submesophotic grouper (Hyporthodus quernus). Three of these four species also have elevated genetic diversity in the mid-archipelago. Biophysical larval dispersal models from previous studies indicate that this elevated diversity may result from larval supplement from Johnston Atoll, ∼800 km southwest of Hawaii. In this case the boundaries of stocks for fishery management cannot be defined simply in terms of geography, and fishery management in Hawaii may need to incorporate external larval supply into management plans.


Assuntos
Peixes/genética , Repetições de Microssatélites/genética , Alelos , Animais , Teorema de Bayes , Análise por Conglomerados , Citocromos b/genética , DNA Mitocondrial/genética , Pesqueiros , Variação Genética , Genética Populacional , Genótipo , Geografia , Havaí , Nucleotídeos/genética , Filogeografia , Tamanho da Amostra
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...