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Description and phylogeny of Namalycastis jaya sp. n. (Polychaeta, Nereididae, Namanereidinae) from the southwest coast of India
Namalycastis jaya sp. n. (Polychaeta: Nereididae: Namanereidinae)is described from the southern coast of Kerala in southwest India. One important characteristic feature of the species is the lack of notochaetae in all parapodia, a characteristic that it shares with at least two other species, Namalycastis elobeyensis Glasby, 1999and Namalycastis hawaiiensis Johnson, 1903. It differs from Namalycastis elobeyensis by virtue of its smaller antennae, unequal eye size, bilobed acicular neuropodial ligule and multi-incised pygidium rim. Moreover, it differs from Namalycastis hawaiiensis by having fewer teeth on the serrated blades of the sub-neuroacicular falciger in chaetiger 10, and by possessing finely serrated falcigers in posterior segments. Beyond morphological analyses, molecular phylogenetics was used for the first time for Namalycastis to support population monophyly and recognition of the new species.The analysis, using both mitochondrial and nuclear data, corroborated the morphological analysis in suggesting that our specimens represent an as yet undescribed species, Namalycastis jaya sp. n., which forms a monophyletic group among the sampled nereidid taxa. Finally, a taxonomic key for Namalycastis species recorded from the Indian region is provided.Organismic and Evolutionary Biolog
The making of a branching annelid: an analysis of complete mitochondrial genome and ribosomal data of Ramisyllis multicaudata
Ramisyllis multicaudata is a member of Syllidae (Annelida, Errantia, Phyllodocida) with a remarkable branching body plan. Using a next-generation sequencing approach, the complete mitochondrial
genomes of R. multicaudata and Trypanobia sp. are sequenced and analysed, representing the first ones from Syllidae. The gene order in these two syllids does not follow the order proposed as the putative ground pattern in Errantia. The phylogenetic relationships of R. multicaudata are discerned using a phylogenetic approach with the nuclear 18S and the mitochondrial 16S and cox1 genes. Ramisyllis multicaudata is the sister group of a clade containing Trypanobia species. Both genera, Ramisyllis and Trypanobia, together with Parahaplosyllis, Trypanosyllis, Eurysyllis, and Xenosyllis are located in a long branched clade. The long branches are explained by an accelerated mutational rate in the 18S rRNA gene. Using a phylogenetic backbone, we propose a scenario in which the
postembryonic addition of segments that occurs in most syllids, their huge diversity of reproductive modes, and their ability to regenerate lost parts, in combination, have provided an evolutionary basis to develop a new branching body pattern as realised in Ramisyllis
Is Namalycastis abiuma (Grube, 1871) (Annelida: Nereididae) restricted to its type-locality? Evidence from morphological and molecular data
Namalycastis abiuma has been recorded as a worldwide distributed species, found in most tropical and subtropicalmangroves and estuarine environments. However, this status has been questioned in several publications, whichindicate that several distinct species are being identified under the name N. abiuma. In this study, we performa morphological analysis, along with a series of species delimitation tests and a phylogenetic analysisâusingthe molecular marker 16Sâto evaluate whether analyzed populations previously identified as Namalycastisabiuma belong to the same species. We used sequences from the GenBank database in the analysis, as well assix newly sequenced specimens collected from the coast of Brazil, two of them from the N. abiuma type-locality.For species delimitation, we applied the Generalized Mixed Yule Coalescent (GMYC), the Assemble Speciesby Automatic Partitioning (ASAP), and the Multi-rate Poisson Tree Processes (mPTP) tests. Results from GMYCand ASAP suggest that Namalycastis abiuma may be endemic to the type-locality and that all other populationsstudied represent a second distinct species. However, mPTP indicates that all Namalycastis species includedshould be grouped into one single species. The mPTP results seem to be biased due to data limitation as it showedpoor statistical support. Our morphological data, especially on the shape and dentition of the sub-neuroacicularfalciger blades, support the GMYC and ASAP results, suggesting restricted endemism for Namalycastis abiuma.Based on these results, we conclude that N. abiuma is restricted to its type-locality and we provide a descriptionof a new species, Namalycastis lanai sp. nov. occurring in Brazilian waters from 22°S to 27°S, including, at itssouthern range, an overlap with N. abiuma at FlorianĂłpolis. Finally, we provide a key to all Namalycastis speciesfound in Brazil
Confirmation of the exotic status of Marphysa victori Lavesque, Daffe, BonifĂĄcio & Hutchings, 2017 (Annelida) in French waters and synonymy of Marphysa bulla Liu, Hutchings & Kupriyanova, 2018
The bait worm Marphysa victori Lavesque, Daffe, BonifĂĄcio & Hutchings, 2017
was originally described from Arcachon Bay, France. In the original description,
the authors suggested that it may have been introduced, although definitive
evidence was lacking at the time. In this paper, we confirm that M. victori is an
exotic species originating from East Asia, probably a native of China or Japan. This
species was most likely introduced into Arcachon Bay in the 1970s with non-native
oysters Crassostrea gigas Thunberg, 1793. The Asiatic origin of this species is
confirmed based on both morphological and molecular evidence. Comparison of
the type specimens of M. victori with those of Marphysa bulla Liu, Hutchings &
Kupriyanova, 2018 described from the Yellow Sea, China, showed no morphological
or molecular differences and therefore the more recently named M. bulla is
relegated to a junior synonym. This is the first example of a large-sized errant
invertebrate species being introduced with oysters into Arcachon Bay.Initiative d'excellence de l'Université de Bordeau
Recovery of a temperate reef assemblage in a marine protected area following the exclusion of towed demersal fishing.
Marine Protected Areas MPA have been widely used over the last 2 decades to address human impacts on marine habitats within an ecosystem management context. Few studies have quantified recovery of temperate rocky reef communities following the cessation of scallop dredging or demersal trawling. This is critical information for the future management of these habitats to contribute towards conservation and fisheries targets. The Lyme Bay MPA, in south west UK, has excluded towed demersal fishing gear from 206 km(2) of sensitive reef habitat using a Statutory Instrument since July 2008. To assess benthic recovery in this MPA we used a flying video array to survey macro epi-benthos annually from 2008 to 2011. 4 treatments (the New Closure, previously voluntarily Closed Controls and Near or Far Open to fishing Controls) were sampled to test a recovery hypothesis that was defined as 'the New Closure becoming more similar to the Closed Controls and less similar to the Open Controls'. Following the cessation of towed demersal fishing, within three years positive responses were observed for species richness, total abundance, assemblage composition and seven of 13 indicator taxa. Definitive evidence of recovery was noted for species richness and three of the indicator taxa (Pentapora fascialis, Phallusia mammillata and Pecten maximus). While it is hoped that MPAs, which exclude anthropogenic disturbance, will allow functional restoration of goods and services provided by benthic communities, it is an unknown for temperate reef systems. Establishing the likely timescales for restoration is key to future marine management. We demonstrate the early stages of successful recruitment and link these to the potential wider ecosystem benefits including those to commercial fisheries
Actively forming Kuroko-type volcanic-hosted massive sulfide (VHMS) mineralization at Iheya North, Okinawa Trough, Japan
Modern seafloor hydrothermal systems provide important insights into the formation and discovery of ancient volcanic-hosted massive sulfide (VHMS) deposits. In 2010, Integrated Ocean Drilling Program (IODP) Expedition 331 drilled five sites in the Iheya North hydrothermal field in the middle Okinawa Trough back-arc basin, Japan. Hydrothermal alteration and sulfide mineralization is hosted in a geologically complex, mixed sequence of coarse pumiceous volcaniclastic and fine hemipelagic sediments, overlying a dacitic to rhyolitic volcanic substrate. At site C0016, located adjacent to the foot of the actively venting North Big Chimney massive sulfide mound, massive sphalerite-(pyrite-chalcopyrite ± galena)-rich sulfides were intersected (to 30.2% Zn, 12.3% Pb, 2.68% Cu, 33.1 ppm Ag and 0.07 ppm Au) that strongly resemble the black ore of the Miocene-age Kuroko deposits of Japan. Sulfide mineralization shows clear evidence of formation through a combination of surface detrital and subsurface chemical processes, with at least some sphalerite precipitating into void space in the rock. Volcanic rocks beneath massive sulfides exhibit quartz-muscovite/illite and quartz-Mg-chlorite alteration reminiscent of VHMS proximal footwall alteration associated with Kuroko-type deposits, characterized by increasing MgO, Fe/Zn and Cu/Zn with depth. Recovered felsic footwall rocks are of FII to FIII affinity with well-developed negative Eu anomalies, consistent with VHMS-hosting felsic rocks in Phanerozoic ensialic arc/back-arc settings worldwide. Site C0013, âŒ100 m east of North Big Chimney, represents a likely location of recent high temperature discharge, preserved as surficial coarse-grained sulfidic sediments (43.2% Zn, 4.4% Pb, 5.4% Cu, 42 ppm Ag and 0.02 ppm Au) containing high concentrations of As, Cd, Mo, Sb, and W. Near surface hydrothermal alteration is dominated by kaolinite and muscovite with locally abundant native sulfur, indicative of acidic hydrothermal fluids. Alteration grades to Mg-chlorite dominated assemblages at depths of >5 mbsf (metres below sea floor). Late coarse-grained anhydrite veining overprints earlier alteration and is interpreted to have precipitated from down welling seawater as hydrothermal activity waned. At site C0014, âŒ350 m farther east, hydrothermal assemblages are characterized by illite/montmorillonite, with Mg-chlorite present at depths below âŒ30 mbsf. Recovered lithologies from distal, recharge site C0017 are unaltered, with low MgO, FeO and base metal concentrations. Mineralization and alteration assemblages are consistent with the Iheya North system representing a modern analogue for Kuroko-type VHMS mineralization. Fluid flow is focussed laterally along pumiceous volcaniclastic strata (compartmentalized between impermeable hemipelagic sediments), and vertically along faults. The abundance of Fe-poor sphalerite and Mg-rich chlorite (clinochlore/penninite) is consistent with the lower Fe budget, temperature and higher oxidation state of felsic volcanic-hosted hydrothermal systems worldwide compared to Mid Ocean Ridge black smoker systems
Manganese in the shell of the bivalve Mytilus edulis: Seawater Mn or physiological control?
Manganese in the shell calcite of marine bivalves has been suggested to reflect ambient seawater Mn concentrations, thus providing a high-resolution archive of past seawater Mn concentrations. However, a quantitative relationship between seawater Mn and shell Mn/Ca ratios, as well as clear understanding of which process(es) control(s) shell Mn/Ca, are still lacking. Blue mussels, Mytilus edulis, were grown in a one-year duration field experiment in the Menai Strait, U.K., to study the relationship between seawater particulate and dissolved Mn2+ concentrations and shell calcite Mn/Ca ratios. Shell Mn/Ca showed a well-defined intra-annual double-peak, with maximum values during early spring and early summer and low values during autumn and winter. Seawater particulate Mn peaked during winter and autumn, with a series of smaller peaks during spring and summer, whereas dissolved Mn2+ exhibited a marked single maximum during late-spring to early-summer, being low during the remainder of the year. Consequently, neither seawater particulate Mn nor dissolved Mn2+ concentrations explain the intra-annual variation of shell Mn/Ca ratios. A physiological control on shell Mn/Ca ratios is evident from the strong similarity and timing of the double-peaked intra-annual variations of Mn/Ca and shell growth rate (SGR), the latter corresponding to periods of increased metabolic activity (as indicated by respiration rate). It is thus likely that in M. edulis SGR influences shell Mn/Ca by altering the concentration or activity of Mn2+ within the extra-pallial fluid (EPF), by changing the flux of Mn into or the proportion of protein bound Mn within the EPF. By linking shell Mn/Ca ratios to the endogenous and environmental factors that determine growth and metabolic activity, this study helps to explain the lack of a consistent relationship between shell Mn/Ca in marine bivalve shell calcite and seawater particulate and dissolved Mn2+ concentrations. The use of Mn content from M. edulis shell calcite as a proxy for the dissolved and/or particulate Mn concentrations, and thus the biogeochemical processes that control them, remains elusive
Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19
IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19.
Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19.
DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 nonâcritically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022).
INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (nâ=â257), ARB (nâ=â248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; nâ=â10), or no RAS inhibitor (control; nâ=â264) for up to 10 days.
MAIN OUTCOMES AND MEASURES The primary outcome was organ supportâfree days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes.
RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ supportâfree days among critically ill patients was 10 (â1 to 16) in the ACE inhibitor group (nâ=â231), 8 (â1 to 17) in the ARB group (nâ=â217), and 12 (0 to 17) in the control group (nâ=â231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ supportâfree days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively).
CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes.
TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570
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