370 research outputs found
The Marine Algal Flora of Bantry Bay, Co. Cork
A documentation of the marine algal flora of Bantry Bay, incorporating distributional, ecological and systematic data, is presented with a view to establishing distribution patterns, and so that an indication of the species diversity of selected shores might be available in the event of major environmental change in the future. Qualitative investigations, chiefly in the littoral zone, were carried out at eleven sites in the inner part of Bantry Bay during 1969-1972. The resulting list contains a total of 166 species, of which 88 are new records for the Bay and 7 are new records for County Cork. The sites at which each species was found are enumerated, together with grid references, brief descriptions of the topography, and notes on the algal communities
Strain selection in the edible brown seaweed Alaria esculenta: Genetic fingerprinting and hybridization studies under laboratory conditions
The genus Alaria presently includes 12 species, 11 of which are located in the cold temperate North Pacific and only one is found in the North Atlantic (Widdowson, 1971). The North Atlantic species Alaria esculenta has two northern forms, A. esculenta forma grandifolia and forma pylaii (LĂŒning, 1990). The study presented here will concentrate on the genetic fingerprinting of Alaria esculenta, the most common North Atlantic species, and hybridisation of members of the Laminariaceae.Funder: Marine Institut
Phase II: Strain hybridisation field experiments and genetic fingerprinting of the edible brown seaweed Alaria esculenta
Under phase II of the Marine Research Measure several field trials were performed with five biogeographical dispersed North Atlantic strains and their hybrids of the edible brown alga Alaria esculenta at Ard Bay, Carna, Co. Galway. The weight, length, width, biomass per meter rope, growth rate and protein level were measured.
The fastest-growing crosses were produced with female Norway gametophytes together with male gametophytes of other strains. The Canadian selfcross produced most biomass of over 45 kg per meter rope. The female Iceland x male Ireland crossing produced the second highest biomass figure of 13.75 kg wet weight per meter rope, while the Irish self cross using a strain from the Aran Islands produced 7.4 kg wet weight per meter.
The Canadian selfcross expressed the highest protein level followed by the female Newfoundland x male Norway hybrid. These strains and hybrids are well suited to be included in a protein rich macro-herbivore diet. The Irish native strain showed a lower protein level of 8% of the wet weight.
Genetic fingerprinting using RFLPs did not show any genetic differences amongst the strains in respect of the DNA examined. A detailed sequencing study on the Rubisco spacer region showed a negligible 3 bp difference between the Irish and Canadian strains
In conclusion, the Canadian strain or hybrids derived from female Canada gametophytes or female Iceland gametophytes produce more biomass per meter rope and grow larger and wider in size compared to the native Irish strain. They Canadian strain also showed the highest protein values in the field trials and hence are most suited to be applied in Irish aquaculture of the brown seaweed Alaria esculenta.Funder: Marine Institut
Marine forests of the Mediterranean-Atlantic Cystoseira tamariscifolia complex show a southern Iberian genetic hotspot and no reproductive isolation in parapatry
Climate-driven range-shifts create evolutionary opportunities for allopatric divergence and subsequent contact, leading to genetic structuration and hybrid zones. We investigate how these processes influenced the evolution of a complex of three closely related Cystoseira spp., which are a key component of the Mediterranean-Atlantic seaweed forests that are undergoing population declines. The C. tamariscifolia complex, composed of C. tamariscifolia s.s., C. amentacea and C. mediterranea, have indistinct boundaries and natural hybridization is suspected. Our aims are to (1) infer the genetic structure and diversity of these species throughout their distribution ranges using microsatellite markers to identify ancient versus recent geographical populations, contact zones and reproductive barriers, and (2) hindcast past distributions using niche models to investigate the influence of past range shifts on genetic divergence at multiple spatial scales. Results supported a single, morphologically plastic species the genetic structure of which was incongruent with a priori species assignments. The low diversity and low singularity in northern European populations suggest recent colonization after the LGM. The southern Iberian genetic hotspot most likely results from the role of this area as a climatic refugium or a secondary contact zone between differentiated populations or both. We hypothesize that life-history traits (selfing, low dispersal) and prior colonization effects, rather than reproductive barriers, might explain the observed genetic discontinuities.Pew Charitable Trusts (USA); MARINERA, Spain [CTM2008-04183-E/MAR]; FCT (Portugal) [FCT-BIODIVERSA/004/2015, CCMAR/Multi/04326/2013, SFRH/BPD/107878/2015, SFRH/BPD/85040/2012]; FPU fellowship of the Spanish Ministry of Education; European Community ASSEMBLE visiting grant [00399/2012]; University of Cadi
A systematic review of floating and beach landing records of Sargassum beyond the Sargasso Sea
Sargassum algal blooms on ocean surfaces and landings of huge Sargassum mats on beaches is an emerging global environmental challenge with wide socio-economic and environmental implications. Literature on Sargassum growth cycles, travel patterns, species and morphotypes, and quantified impacts have tended to focus on a geographic region, or a specific event. Few, if any, publications document long term continuous monitoring of Sargassum blooms in large areas such as the Pacific, or the tropical Atlantic. To address this gap, this paper systematically reviews the global evidence of Sargassum bloom monitoring beyond the Sargasso Sea, and identifies gaps in the evidence base of floating and landing influxes. This systematic review uses combinations of two key terms relating to Sargassum and monitoring, and utilises the resources in ISI Web of Knowledge, Scopus and Google Scholar. The analysis moves us past a classic literature review, and produces an unbiased assessment of empirical research on Sargassum monitoring from 1960 to 2019. We find a significant research focus on open-ocean blooms and floating mats whereas research on beach landings and their associated impacts is comparatively limited. Research is focused within specific countries or water bodies (notably, the Gulf of Mexico, the Caribbean and North Atlantic Ocean) and tends not to comprehensively assess neighbouring or regional shorelines, for example, West Africa and Central America. There was a lack of consistency in the application of methods for quantifying Sargassum biomass volume (including dry/wet weight, unit of measurement, and spatial extent of calculations). Further, in many publications Sargassum species identification was omitted. Given current attempts to understand the drivers and impacts of the exponential growth in Sargassum in some parts of the world, a consistent and replicable research approach to monitoring Sargassum could support creation of a Sargassum evidence database. To move this agenda forwards, we propose a definition for a Sargassum 'event': a continuous bloom of any Sargassum in open oceans, or, an aggregation of landed Sargassum, with the potential to disrupt social, economic or ecosystem functioning, or to impact human health. This review highlights the importance of standardising Sargassum monitoring methods to facilitate improved documentation of temporal and spatial patterns of Sargassum blooms and beach landings
A Study of Selected Maërl Beds in Irish Waters and their Potential for Sustainable Extraction
Although maërl beds are both of economic importance and conservation interest, data on the distribution of beds and their associated communities are lacking in Irish waters. This report describes the spatial distribution and volume of the maërl resource (Lithothamnion corallioides, Phymatolithon calcareum) along the west coast of Ireland from Donegal to Cork.
Taking an average thickness of 2m (range: 0.1 â 3m) the current study estimates that the total national exploitable maĂ«rl bearing resource is of the order of 3 x 10^6 metres cubed. The Report outlines guidelines for the exploitation of this natural resource, which because of its extremely low growth rate, cannot be considered a renewable resource in the strictest sense.Funder: Marine Institut
Incidence, predictors, and economic impact of contrast induced nephropathy: results in 8,628 patients treated with percutaneous coronary interventions
Asymmetric Synthesis and Biological Screening of Quinoxaline-Containing Synthetic Lipoxin Aâ Mimetics (QNX-sLXms)
Failure to resolve inflammation underlies many prevalent pathologies. Recent insights have identified lipid mediators, typified by lipoxins (LXs), as drivers of inflammation resolution, suggesting potential therapeutic benefit. We report the asymmetric preparation of novel quinoxaline-containing synthetic-LXA4-mimetics (QNX-sLXms). Eight novel compounds were screened for their impact on inflammatory responses. Structureâactivity relationship (SAR) studies showed that (R)-6 (also referred to as AT-02-CT) was the most efficacious and potent anti-inflammatory compound of those tested. (R)-6 significantly attenuated lipopolysaccharide (LPS)- and tumor-necrosis-factor-α (TNF-α)-induced NF-ÎșB activity in monocytes and vascular smooth muscle cells. The molecular target of (R)-6 was investigated. (R)-6 activated the endogenous LX receptor formyl peptide receptor 2 (ALX/FPR2). The anti-inflammatory properties of (R)-6 were further investigated in vivo in murine models of acute inflammation. Consistent with in vitro observations, (R)-6 attenuated inflammatory responses. These results support the therapeutic potential of the lead QNX-sLXm (R)-6 in the context of novel inflammatory regulators
Asymmetric Synthesis and Biological Screening of Quinoxaline-Containing Synthetic Lipoxin A4 Mimetics (QNX-sLXms)
Failure to resolve inflammation underlies many
prevalent pathologies. Recent insights have identified lipid
mediators, typified by lipoxins (LXs), as drivers of inflammation
resolution, suggesting potential therapeutic benefit. We report the
asymmetric preparation of novel quinoxaline-containing syntheticLXA4-mimetics (QNX-sLXms). Eight novel compounds were
screened for their impact on inflammatory responses. Structureâ
activity relationship (SAR) studies showed that (R)-6 (also
referred to as AT-02-CT) was the most efficacious and potent
anti-inflammatory compound of those tested. (R)-6 significantly
attenuated lipopolysaccharide (LPS)- and tumor-necrosis-factor-α
(TNF-α)-induced NF-ÎșB activity in monocytes and vascular
smooth muscle cells. The molecular target of (R)-6 was investigated. (R)-6 activated the endogenous LX receptor formyl peptide
receptor 2 (ALX/FPR2). The anti-inflammatory properties of (R)-6 were further investigated in vivo in murine models of acute
inflammation. Consistent with in vitro observations, (R)-6 attenuated inflammatory responses. These results support the therapeutic
potential of the lead QNX-sLXm (R)-6 in the context of novel inflammatory regulators
Genome of the red alga Porphyridium purpureum
The limited knowledge we have about red algal genomes comes from the highly specialized extremophiles, Cyanidiophyceae. Here, we describe the first genome sequence from a mesophilic, unicellular red alga, Porphyridium purpureum. The 8,355 predicted genes in P. purpureum, hundreds of which are likely to be implicated in a history of horizontal gene transfer, reside in a genome of 19.7 Mbp with 235 spliceosomal introns. Analysis of light-harvesting complex proteins reveals a nuclear-encoded phycobiliprotein in the alga. We uncover a complex set of carbohydrate-active enzymes, identify the genes required for the methylerythritol phosphate pathway of isoprenoid biosynthesis, and find evidence of sexual reproduction. Analysis of the compact, function-rich genome of P. purpureum suggests that ancestral lineages of red algae acted as mediators of horizontal gene transfer between prokaryotes and photosynthetic eukaryotes, thereby significantly enriching genomes across the tree of photosynthetic life
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