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https://www.readbyqxmd.com/read/28634373/an-assessment-of-mobile-predator-populations-along-shallow-and-mesophotic-depth-gradients-in-the-hawaiian-archipelago
#1
Jacob Asher, Ivor D Williams, Euan S Harvey
Large-bodied coral reef roving predators (sharks, jacks, snappers) are largely considered to be depleted around human population centers. In the Hawaiian Archipelago, supporting evidence is primarily derived from underwater visual censuses in shallow waters (≤30 m). However, while many roving predators are present or potentially more abundant in deeper strata (30-100 m+), distributional information remains sparse. To partially fill that knowledge gap, we conducted surveys in the remote Northwestern Hawaiian Islands (NWHI) and populated Main Hawaiian Islands (MHI) from 2012-2014 using baited remote underwater stereo-video...
June 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28625747/molecular-identification-and-characterization-of-haptoglobin-in-teleosts-revealed-an-important-role-on-fish-viral-infections
#2
Héctor Cordero, Chang Hong Li, Elena Chaves-Pozo, María Ángeles Esteban, Alberto Cuesta
Haptoglobin (Hp) molecule has been cloned and characterized in two marine teleosts (gilthead seabream and European sea bass), obtaining putative proteins of 319 residues encoded by an ORF of 960 bp in both species. However, the matrix of similarity revealed low identities among bony fish species 78.9% (seabream-sea bass), 43% (seabream/seabass-zebrafish) and lower than 20% with sharks and human. The protein sequences showed a signal peptide from the position 1 to 23, a trypsin domain from 47 to 297, and several predicted disulfide bridges and glycosylation sites...
June 15, 2017: Developmental and Comparative Immunology
https://www.readbyqxmd.com/read/28617322/chondroitin-sulfate-rich-extract-of-skate-cartilage-attenuates-lipopolysaccharide-induced-liver-damage-in-mice
#3
Yeong Ok Song, Mijeong Kim, Minji Woo, Jang-Mi Baek, Keon-Hee Kang, Sang-Ho Kim, Seong-Soo Roh, Chan Hum Park, Kap-Seop Jeong, Jeong-Sook Noh
The protective effects of a chondroitin sulfate-rich extract (CSE) from skate cartilage against lipopolysaccharide (LPS)-induced hepatic damage were investigated, and its mechanism of action was compared with that of chondroitin sulfate (CS) from shark cartilage. ICR mice were orally administrated 200 mg/kg body weight (BW) of CS or 400 mg/kg BW of CSE for 3 consecutive days, followed by a one-time intraperitoneal injection of LPS (20 mg/kg BW). The experimental groups were vehicle treatment without LPS injection (NC group), vehicle treatment with LPS injection (LPS group), CS pretreatment with LPS injection (CS group), and CSE pretreatment with LPS injection (CSE group)...
June 15, 2017: Marine Drugs
https://www.readbyqxmd.com/read/28616238/validation-of-a-portable-waterproof-blood-ph-analyser-for-elasmobranchs
#4
Brendan Talwar, Ian A Bouyoucos, Oliver Shipley, Jodie L Rummer, John W Mandelman, Edward J Brooks, R Dean Grubbs
Quantifying changes in blood chemistry in elasmobranchs can provide insights into the physiological insults caused by anthropogenic stress, and can ultimately inform conservation and management strategies. Current methods for analysing elasmobranch blood chemistry in the field are often costly and logistically challenging. We compared blood pH values measured using a portable, waterproof pH meter (Hanna Instruments HI 99161) with blood pH values measured by an i-STAT system (CG4+ cartridges), which was previously validated for teleost and elasmobranch fishes, to gauge the accuracy of the pH meter in determining whole blood pH for the Cuban dogfish (Squalus cubensis) and lemon shark (Negaprion brevirostris)...
2017: Conservation Physiology
https://www.readbyqxmd.com/read/28616174/spatial-overlap-of-shark-nursery-areas-and-the-salmon-farming-industry-influences-the-trophic-ecology-of-squalus-acanthias-on-the-southern-coast-of-chile
#5
Juan Diego Gaitán-Espitia, Daniela Gómez, Alistair J Hobday, Ross Daley, Julio Lamilla, Leyla Cárdenas
Potential interactions between marine predators and humans arise in the southern coast of Chile where predator feeding and reproduction sites overlap with fisheries and aquaculture. Here, we assess the potential effects of intensive salmon aquaculture on food habits, growth, and reproduction of a common predator, the spiny dogfish-identified as Squalus acanthias via genetic barcoding. A total of 102 (89 females and 13 males) individuals were collected during winter and summer of 2013-2014 from the Chiloé Sea where salmon aquaculture activities are concentrated...
June 2017: Ecology and Evolution
https://www.readbyqxmd.com/read/28603671/spatial-variation-in-coral-reef-fish-and-benthic-communities-in-the-central-saudi-arabian-red-sea
#6
Maha T Khalil, Jessica Bouwmeester, Michael L Berumen
Local-scale ecological information is critical as a sound basis for spatial management and conservation and as support for ongoing research in relatively unstudied areas. We conducted visual surveys of fish and benthic communities on nine reefs (3-24 km from shore) in the Thuwal area of the central Saudi Arabian Red Sea. Fish biomass increased with increasing distance from shore, but was generally low compared to reefs experiencing minimal human influence around the world. All reefs had a herbivore-dominated trophic structure and few top predators, such as sharks, jacks, or large groupers...
2017: PeerJ
https://www.readbyqxmd.com/read/28602510/population-genetics-of-the-deep-sea-bluntnose-sixgill-shark-hexanchus-griseus-revealing-spatial-genetic-heterogeneity
#7
Noel Vella, Adriana Vella
Hexanchus griseus is a globally distributed deep-water shark species. It inhabits tropical and temperate waters throughout the world, including the Mediterranean Sea where it is by-caught by small-scale fisheries in the region. In this study, we analysed the genetic variation of H. griseus specimens collected from different areas within and outside the Mediterranean region, to assess its genetic connectivity. The mitochondrial DNA (mtDNA) sequence analysed in this study ranged from cytochrome b to 16S rRNA genes including the control region, the 12S rRNA gene and the interspersed tRNA genes in the region, covering a total of 3731 to 3914 nucleotides...
June 8, 2017: Marine Genomics
https://www.readbyqxmd.com/read/28594833/diet-and-trophic-ecology-of-the-tiger-shark-galeocerdo-cuvier-from-south-african-waters
#8
Matthew L Dicken, Nigel E Hussey, Heather M Christiansen, Malcolm J Smale, Nomfundo Nkabi, Geremy Cliff, Sabine P Wintner
Knowledge of the diet and trophic ecology of apex predators is key for the implementation of effective ecosystem as well as species-based management initiatives. Using a combination of stomach content data and stable isotope analysis (δ15N and δ13C) the current study provides information on size-based and sex-specific variations in diet, trophic position (TP) and foraging habitat of tiger sharks (Galeocerdo cuvier) caught in the KwaZulu-Natal Sharks Board bather protection program. This study presents the longest time-series and most detailed analysis of stomach content data for G...
2017: PloS One
https://www.readbyqxmd.com/read/28591222/ecological-impact-of-the-end-cretaceous-extinction-on-lamniform-sharks
#9
Rachel A Belben, Charlie J Underwood, Zerina Johanson, Richard J Twitchett
Lamniform sharks are apex marine predators undergoing dramatic local and regional decline worldwide, with consequences for marine ecosystems that are difficult to predict. Through their long history, lamniform sharks have faced widespread extinction, and understanding those 'natural experiments' may help constrain predictions, placing the current crisis in evolutionary context. Here we show, using novel morphometric analyses of fossil shark teeth, that the end-Cretaceous extinction of many sharks had major ecological consequences...
2017: PloS One
https://www.readbyqxmd.com/read/28586694/challenges-and-priorities-in-shark-and-ray-conservation
#10
REVIEW
Nicholas K Dulvy, Colin A Simpfendorfer, Lindsay N K Davidson, Sonja V Fordham, Amie Bräutigam, Glenn Sant, David J Welch
Sharks, rays, and chimaeras (Class Chondrichthyes; herein 'sharks') are the earliest extant jawed vertebrates and exhibit some of the greatest functional diversity of all vertebrates. Ecologically, they influence energy transfer vertically through trophic levels and sometimes trophic cascades via direct consumption and predation risk. Through movements and migrations, they connect horizontally and temporally across habitats and ecosystems, integrating energy flows at large spatial scales and across time. This connectivity flows from ontogenetic growth in size and spatial movements, which in turn underpins their relatively low reproductive rates compared with other exploited ocean fishes...
June 5, 2017: Current Biology: CB
https://www.readbyqxmd.com/read/28586686/vision-and-lack-of-vision-in-the-ocean
#11
Justin Marshall
As land-locked animals, when we visualise the ocean our mind's eye may see crashing waves or a vast blue expanse stretching to the horizon, a raft of torpedoing penguins, a glimpse of colourful coral reef fish from the shark-free safety of a sandy beach. Underwater, the crystal-clear, and in fact not at all silent, world of Jacques Cousteau, or more recently David Attenborough, is a wonderland that some cannot wait to witness first hand as divers, while others are content to see it on a screen. Spend a bit of time underwater, in the English Channel for example, and a few facts emerge...
June 5, 2017: Current Biology: CB
https://www.readbyqxmd.com/read/28580133/the-elephant-shark-methylome-reveals-conservation-of-epigenetic-regulation-across-jawed-vertebrates
#12
Julian R Peat, Oscar Ortega-Recalde, Olga Kardailsky, Timothy A Hore
BACKGROUND: Methylation of CG dinucleotides constitutes a critical system of epigenetic memory in bony vertebrates, where it modulates gene expression and suppresses transposon activity. The genomes of studied vertebrates are pervasively hypermethylated, with the exception of regulatory elements such as transcription start sites (TSSs), where the presence of methylation is associated with gene silencing. This system is not found in the sparsely methylated genomes of invertebrates, and establishing how it arose during early vertebrate evolution is impeded by a paucity of epigenetic data from basal vertebrates...
2017: F1000Research
https://www.readbyqxmd.com/read/28567684/possible-maternal-offloading-of-metals-in-the-plasma-uterine-and-capsule-fluid-of-pregnant-ragged-tooth-sharks-carcharias-taurus-on-the-east-coast-of-south-africa
#13
Kristina Naidoo, Anil Chuturgoon, Geremy Cliff, Sanil Singh, Megan Ellis, Nicholas Otway, Andre Vosloo, Michael Gregory
We studied the possible metal offloading onto the progeny of three pregnant female ragged-tooth sharks (Carcharias taurus) (C. taurus). The presences of five metals, i.e. aluminium (Al), arsenic (As), cadmium (Cd), lead (Pb) and selenium (Se) were validated by mass spectrometry in the maternal plasma as well as the intracapsular and uterine fluids (UF) in which embryos develop. Metals were ranked in a decreasing concentration as follows: Plasma: As > Al > Se > Pb > Cd; ICF: As > Se > Al > Cd > Pb and UF: As > Se > Al > Cd > Pb...
May 31, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28562602/drivers-of-abundance-and-spatial-distribution-of-reef-associated-sharks-in-an-isolated-atoll-reef-system
#14
David M Tickler, Tom B Letessier, Heather J Koldewey, Jessica J Meeuwig
We investigated drivers of reef shark demography across a large and isolated marine protected area, the British Indian Ocean Territory Marine Reserve, using stereo baited remote underwater video systems. We modelled shark abundance against biotic and abiotic variables at 35 sites across the reserve and found that the biomass of low trophic order fish (specifically planktivores) had the greatest effect on shark abundance, although models also included habitat variables (depth, coral cover and site type). There was significant variation in the composition of the shark assemblage at different atolls within the reserve...
2017: PloS One
https://www.readbyqxmd.com/read/28556294/combined-angiography-and-late-gadolinium-enhancement-acquisition-to-improve-assessment-of-pulmonary-vein-isolation-for-atrial-fibrillation
#15
Adrian Lam, Erica Okene, Ankit Parikh, Xiaodong Zhong, Thor Tejada, Michael Hoskins, Michael Lloyd, John N Oshinski
PURPOSE: To develop a Shared K-space (SharK) magnetic resonance imaging (MRI) sequence that combines angiographic and late gadolinium enhancement (LGE) acquisitions to improve atrial wall segmentation and scar identification, and to develop a novel visualization method that quantifies scar encirclement of pulmonary veins postablation treatment for atrial fibrillation. MATERIALS AND METHODS: A SharK sequence was developed and used at 3T to image the left atrium in 11 patients postcryoballoon ablation...
May 28, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28552352/calcium-isotopic-evidence-for-vulnerable-marine-ecosystem-structure-prior-to-the-k-pg-extinction
#16
Jeremy E Martin, Peggy Vincent, Théo Tacail, Fatima Khaldoune, Essaid Jourani, Nathalie Bardet, Vincent Balter
The collapse of marine ecosystems during the end-Cretaceous mass extinction involved the base of the food chain [1] up to ubiquitous vertebrate apex predators [2-5]. Large marine reptiles became suddenly extinct at the Cretaceous-Paleogene (K/Pg) boundary, whereas other contemporaneous groups such as bothremydid turtles or dyrosaurid crocodylomorphs, although affected at the familial, genus, or species level, survived into post-crisis environments of the Paleocene [5-9] and could have found refuge in freshwater habitats [10-12]...
June 5, 2017: Current Biology: CB
https://www.readbyqxmd.com/read/28542258/bycatch-in-the-maldivian-pole-and-line-tuna-fishery
#17
Kelsey I Miller, Ibrahim Nadheeh, A Riyaz Jauharee, R Charles Anderson, M Shiham Adam
Tropical tuna fisheries are among the largest worldwide, with some having significant bycatch issues. However, pole-and-line tuna fisheries are widely believed to have low bycatch rates, although these have rarely been quantified. The Maldives has an important pole-and-line fishery, targeting skipjack tuna (Katsuwonus pelamis). In the Maldives, 106 pole-and-line tuna fishing days were observed between August 2014 and November 2015. During 161 fishing events, tuna catches amounted to 147 t: 72% by weight was skipjack, 25% yellowfin tuna (Thunnus albacares) and 3% other tunas...
2017: PloS One
https://www.readbyqxmd.com/read/28532663/recent-developments-in-drug-eluting-devices-with-tailored-interfacial-properties
#18
REVIEW
Eva Sanchez-Rexach, Emilio Meaurio, Jose-Ramon Sarasua
Drug eluting devices have greatly evolved during past years to become fundamental products of great marketing importance in the biomedical field. There is currently a large diversity of highly specialized devices for specific applications, making the development of these devices an exciting field of research. The replacement of the former bare metal devices by devices loaded with drugs allowed the sustained and controlled release of drugs, to achieve the desired local therapeutic concentration of drug. The newer devices have been "engineered" with surfaces containing micro- and nanoscale features in a well-controlled manner, that have shown to significantly affect cellular and subcellular function of various biological systems...
May 4, 2017: Advances in Colloid and Interface Science
https://www.readbyqxmd.com/read/28529682/segmentations-of-the-cartilaginous-skeletons-of-chondrichthyan-fishes-by-the-use-of-state-of-the-art-computed-tomography
#19
Andrew D McQuiston, Callie Crawford, U Joseph Schoepf, Akos Varga-Szemes, Christian Canstein, Matthias Renker, Carlo N De Cecco, Stefan Baumann, Gavin J P Naylor
AIM: To apply dual-source multidetector computed tomography (DSCT) scanning technology in conjunction with computationally assisted segmentation in order to explore and document skeletal variation that has occurred over the course of evolution. METHODS: We examined 4 divergent species of elasmobranchs with high-resolution 3(rd) generation DSCT. The formalin prepared species examined were: Aptychotrema vincentiana, Mitsukurina owstoni, Negaprion brevirostris and Dactylobatus armatus...
April 28, 2017: World Journal of Radiology
https://www.readbyqxmd.com/read/28516259/-poisoning-caused-by-marine-biotoxins
#20
REVIEW
Philipp Hess
This paper presents a short summary of the knowledge on marine biotoxins. As toxins are known for their acute effects, they have been classified here according to the effects they cause in acute human poisoning incidents. Toxins may thus be distinguished into those that affect the nervous system (paralytic and other neurotoxins), memory (amnesic poisons), and the digestive system (diarrhetic toxins). Furthermore, newly emerging toxins, such as ciguatoxins or shark toxins, and factors that lead to the introduction of toxins in new areas, are presented...
May 17, 2017: Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz
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