Age readings of Sebastes marinus otoliths: bias and precision between readers and otolith preparation methods

This study presents a comparative age reading on Sebastes marinus from the Icelandic shelf within an otolith exchange program between institutes in Germany, Iceland and Norway. Out of a series of 212 otolith pairs, one otolith of each pair was prepared by the break-and-burn technique, while the other otolith was used for crosssections. Age reading results are compared between readers and otolith preparation methods in terms of bias and precision, using a set of statistical tests and graphical methods. Significant bias was observed for both the comparison between readers and between methods, mainly caused by deviations between age scores in the higher ages (> 20 years). Precision estimates, involving the high longevity of redfish, were relatively good compared to previous age reading comparisons using other species. In contrast, the age dependent percent agreement was poor (< 30%) for a tolerance level of ± 0 years, particularly for the age range 21-30 years. A tolerance level of ± 3 years, however, lead to around 90% agreement for the age range up to 20 years. The fit of age reading scores with the von-Bertalanffy growth curve was relatively good, providing growth parameters comparable to S. marinus from the Norwegian shelf. The observed problems in bias and precision of age readings should to be improved by continuing with similar Sebastes otolith exchange programs and setting up a further age reading workshop to harmonise the interpretation of growth structures

In Vitro and Ex Vivo Evaluation of Nepafenac-Based Cyclodextrin Microparticles for Treatment of Eye Inflammation

The aim of this study was to design and evaluate novel cyclodextrin (CD)-based aggregate formulations to efficiently deliver nepafenac topically to the eye structure, to treat inflammation and increase nepafenac levels in the posterior segment, thus attenuating the response of inflammatory mediators. The physicochemical properties of nine aggregate formulations containing nepafenac/γ-CD/hydroxypropyl-β (HPβ)-CD complexes as well as their rheological properties, mucoadhesion, ocular irritancy, corneal and scleral permeability, and anti-inflammatory activity were investigated in detail. The results were compared with a commercially available nepafenac suspension, Nevanac® 3 mg/mL. All formulations showed microparticles, neutral pH, and negative zeta potential (–6 to –27 mV). They were non-irritating and nontoxic and showed high permeation through bovine sclera. Formulations containing carboxymethyl cellulose (CMC) showed greater anti-inflammatory activity, even higher than the commercial formulation, Nevanac® 0.3%. The optimized formulations represent an opportunity for topical instillation of drugs to the posterior segment of the eyeThis research was funded by MINECO (SAF2017-83118-R), Agencia Estatal de Investigación (AEI) Spain, Xunta de Galicia (ED431C 2016/008), and FEDER (Spain). B.L.-V. acknowledges an Erasmus+ traineeship (IS-SM2018-81075)S

Mechanisms and consequences of life cycle diversity of beaked redfish, Sebastes mentella

Recent genetic research, supported by life history information, indicates that there are three biological stocks of S. mentella in the Irminger Sea and adjacent waters: a ‘Deep Pelagic’ stock (>500m), a ‘Shallow Pelagic’ stock (<500m), and an ‘Icelandic Slope’ stock. Throughout their range, Sebastes species are adapted to a diversity of ecological niches, with overlapping spatial distributions of different species that have little or no morphological differences. Divergence of behavioral groups into depth-defined adult habitats has led to reproductive isolation, adaptive radiation and speciation of several Sebastes species. Congruent differences in fatty acid composition and parasites suggests that the three genetically distinct populations of S. mentella are adapted to disparate trophic habitats in pelagic waters (shallower and deeper than the deep-scattering layer), and in demersal habitats on the continental slope. Patterns of morphology are also consistent with adaptation to different habitats, because pelagic forms are more streamlined. Although genetic differences and evidence for reproductive isolation are clear, these populations appear to share common nursery habitats on the Greenlandic Shelf. Spatial overlap at early life stages and depth-defined adult populations present challenges for stock identification and fishery management. Effective resource monitoring, conservation and fishery management requires that the spatial definition of management units reflects biological stock structure. We describe a proposal for a redefinition of practical management units that are based on geographic proxies for biological stocks which minimizes mixed-stock catches according to spatial patterns of the recent fishery

Genome-wide analysis yields new loci associating with aortic valve stenosis

Aortic valve stenosis (AS) is the most common valvular heart disease, and valve replacement is the only definitive treatment. Here we report a large genome-wide association (GWA) study of 2,457 Icelandic AS cases and 349,342 controls with a follow-up in up to 4,850 cases and 451,731 controls of European ancestry. We identify two new AS loci, on chromosome 1p21 near PALMD (rs7543130; odds ratio (OR) = 1.20, P = 1.2 × 10−22) and on chromosome 2q22 in TEX41 (rs1830321; OR = 1.15, P = 1.8 × 10−13). Rs7543130 also associates with bicuspid aortic valve (BAV) (OR = 1.28, P = 6.6 × 10−10) and aortic root diameter (P = 1.30 × 10−8), and rs1830321 associates with BAV (OR = 1.12, P = 5.3 × 10−3) and coronary artery disease (OR = 1.05, P = 9.3 × 10−5). The results implicate both cardiac developmental abnormalities and atherosclerosis-like processes in the pathogenesis of AS. We show that several pathways are shared by CAD and AS. Causal analysis suggests that the shared risk factors of Lp(a) and non-high-density lipoprotein cholesterol contribute substantially to the frequent co-occurence of these diseases

Physical and cognitive impact following SARS-CoV-2 infection in a large population-based case-control study

© 2023. The Author(s).BACKGROUND: Persistent symptoms are common after SARS-CoV-2 infection but correlation with objective measures is unclear. METHODS: We invited all 3098 adults who tested SARS-CoV-2 positive in Iceland before October 2020 to the deCODE Health Study. We compared multiple symptoms and physical measures between 1706 Icelanders with confirmed prior infection (cases) who participated, and 619 contemporary and 13,779 historical controls. Cases participated in the study 5-18 months after infection. RESULTS: Here we report that 41 of 88 symptoms are associated with prior infection, most significantly disturbed smell and taste, memory disturbance, and dyspnea. Measured objectively, cases had poorer smell and taste results, less grip strength, and poorer memory recall. Differences in grip strength and memory recall were small. No other objective measure associated with prior infection including heart rate, blood pressure, postural orthostatic tachycardia, oxygen saturation, exercise tolerance, hearing, and traditional inflammatory, cardiac, liver, and kidney blood biomarkers. There was no evidence of more anxiety or depression among cases. We estimate the prevalence of long Covid to be 7% at a median of 8 months after infection. CONCLUSIONS: We confirm that diverse symptoms are common months after SARS-CoV-2 infection but find few differences between cases and controls in objective parameters measured. These discrepancies between symptoms and physical measures suggest a more complicated contribution to symptoms related to prior infection than is captured with conventional tests. Traditional clinical assessment is not expected to be particularly informative in relating symptoms to a past SARS-CoV-2 infection.Peer reviewe

Vertical and Horizontal Distribution of Mesopelagic Fishes along a Transect across the Northern Mid-Atlantic Ridge

A research cruise was made in the Irminger Sea west and southwest of Iceland and adjacent waters on the Icelandic vessel Árni Friðriksson, from 03 Jun-04 Jul 2003. The main purpose was to study distribution and abundance of deepwater redfishes, Sebastes mentella et sp., other pelagic fishes, zooplankton, phytoplankton and the hydrography of the area. Part of the cruise was devoted to a special study on community structure at transect over the northern part of the Mid-Atlantic Ridge (Reykjanes Ridge). In this paper, an overview is given on the composition of the pelagic fish community, both vertically and horizontally, over the northern part of the Reykjanes Ridge. In total, nine trawl hauls were made with a “GLORIA” midwater trawl outfitted with a small mesh size (9-mm) cod-end. Three hauls were made at three different depths west of the Ridge, three above it and three East of the Ridge. A total of 230 nautical miles separated hauls taken west of the Ridge and east of it. A minimum total of 44 species were identified from 23 families. Lanternfishes (Myctophidae), pearlsides (Sternoptychidae), barracudinas (Paralepididae), dragonfishes (Stomiidae) and deep-sea smelts (Microstomatidae) dominated fish catches. Results show that the total number of fishes caught was lowest east of the Ridge, coinciding with warmer deep waters. At all positions both number of species and families increased with depth as the number of individuals decreased with depth

Assessment of golden redfish (Sebastes marinus L) in Icelandic waters

Assessment of redfish has traditionally suffered from the inability to age the fish. For golden redfish in Icelandic waters, length distributions and abundance indices are available both from commercial catch and from surveys, particularly a groundfish survey in March. This paper addresses the use of an age- and length-based cohort model for the assessment of redfish, where all selection curves depend on the length of the fish and information on age is not a prerequisite but can be utilised if available. In the last few years it appears that ageing of this species has been successful and in this paper we compare assessment results of a model that incorporates age information with those that do not. Finally, we calculate yield per recruit, Fmax and F0.1 for the stock. Stock size, catch and fishing mortality are then simulated 10 years ahead using different catch control laws.No disponibl

Report on the joint Icelandic / Norwegian survey on oceanic redfish in the Irminger Sea and adjacent waters, in june/july 1994

An acoustic survey on oceanic redfish (oceanic Sebastes mentella) in the Irminger Sea, in June/July 1994 was carried out by Iceland and Norway. Approximately 190 000 n.m. ^2 were covered. The stock size in the area surveyed was assessed to be about 2.2 million tonnes or 3.5 million individuals. Only depths shallower than 500 meters were included. The oceanic redfish concentrations were densest in the 100-250 m depth layer, mainly within a temperature range of 3° to 4°C. Males were in majority in all areas (55-61 %). The average length of oceanic S. mentella was 36,7 cm, and the average weight 640 g. Females were on the average larger and heavier than males. The percentage of fish with external abnormalities (i.e. Sphyrion lumpi and spots) was much higher for females than for males. The average was 43.5% and the average for fish with abnormal muscular pigmentation, 47.1 %, resp. The maturity stages and the stomach contents were recorded

Cyclodextrin–Amphiphilic Copolymer Supramolecular Assemblies for the Ocular Delivery of Natamycin

Natamycin is the only drug approved for fungal keratitis treatment, but its low water solubility and low ocular penetration limit its efficacy. The purpose of this study was to overcome these limitations by encapsulating the drug in single or mixed micelles and poly(pseudo)rotaxanes. Soluplus and Pluronic P103 dispersions were prepared in 0.9% NaCl and pH 6.4 buffer, with or without α-cyclodextrin (αCD; 10% w/v), and characterized through particle size, zeta potential, solubilization efficiency, rheological properties, ocular tolerance, in vitro drug diffusion, and ex vivo permeation studies. Soluplus micelles (90–103 nm) and mixed micelles (150–110 nm) were larger than Pluronic P103 ones (16–20 nm), but all showed zeta potentials close to zero. Soluplus, Pluronic P103, and their mixed micelles increased natamycin solubility up to 6.00-fold, 3.27-fold, and 2.77-fold, respectively. Soluplus dispersions and poly(pseudo)rotaxanes exhibited in situ gelling capability, and they transformed into weak gels above 30 °C. All the formulations were non-irritant according to Hen’s Egg Test on the Chorioallantoic Membrane (HET-CAM) assay. Poly(pseudo)rotaxanes facilitated drug accumulation into the cornea and sclera, but led to lower natamycin permeability through the sclera than the corresponding micelles. Poly(pseudo)rotaxanes made from mixed micelles showed intermediate natamycin diffusion coefficients and permeability values between those of Pluronic P103-based and Soluplus-based poly(pseudo)rotaxanes. Therefore, the preparation of mixed micelles may be a useful tool to regulate drug release and enhance ocular permeabilityThis research was funded by MINECO [SAF2017-83118-R], Agencia Estatal de Investigación (AEI) Spain, Xunta de Galicia (Grupo de Referencia Competitiva ED431C 2016/008; Agrupación Estratégica en Materiales-AEMAT ED431E 2018/08), and FEDER (Spain). B.L.-V. acknowledges an Erasmus+ traineeship (IS-SM2018-81075)S

Age Readings of Sebastes marinus and S. mentella Otoliths: Bias and Precision Between Readers

14 páginas, 8 figuras, 2 tablas.This study presents comparative otolith-based age readings of golden redfish (Sebastes marinus) from Iceland and demersal as well as pelagic deep-sea redfish (Sebastes mentella) from East Greenland and the Irminger Sea within an otolith exchange program between institutes in Germany, Iceland, Norway and Spain. A total of 571 otoliths were thin-sectioned and read independently in the participating labs. Age reading results were compared between readers in terms of bias and precision, using a set of statistical tests and graphical methods. Significant bias was observed between readers, mainly caused by deviations between age scores in the higher ages (> 20 years). Percent agreement was poor (< 30%) for a tolerance level of ± 0 years, particularly for the age range 21-40 years, which represents the major fraction of the fished stock. A tolerance level of ± 5 years, however, lead to up to 95% agreement for the age ranges up to 20 years. Precision and bias were generally better for S. marinus than they were for S. mentella, pointing to greater difficulties in the interpretation of growth stuctures for the latter species. The mean age of S. mentella with total lengths of 25-30 cm, which were observed to have recruited from the East Greenland shelf into the Irminger Sea during 1998/99, was determined to be 9-10 years. The observed problems in bias and precision of age readings should to be improved by continuing with similar Sebastes otolith exchange programs and setting up a further age reading workshop to harmonise the interpretation of growth structures. Radiometric ageing is currently being finalised and results will be available for the next NWWG meeting.The present study was realised within the REDFISH project (QLK5-CT1999-01222), financially supported by the European Commission within the FP5 research area QUALITY OF LIFE AND MANAGEMENT OF LIVING RESOURCES, Key Action 5: Sustainable Agriculture, Fisheries and Forestry.Peer reviewe