Evaluation of Post-thrombolytic Events to Determine Appropriate ICU Monitoring Duration for Patients with Ischemic Stroke.

BACKGROUND: Standard treatment for eligible patients presenting with acute ischemic stroke (AIS) is thrombolysis with tissue plasminogen activators alteplase or tenecteplase. Current guidelines recommend monitoring patients in an intensive care unit (ICU) for 24 h after thrombolytic therapy. However, recent studies have questioned the need for prolonged ICU monitoring. This retrospective cohort study aims to identify potential candidates for early transition to a lower level of care by assessing risk factors for neurological deterioration, symptomatic intracranial hemorrhage (sICH), or need for ICU intervention within 24 h post-thrombolysis. METHODS: This retrospective cohort study included adult patients 18 years and older with AIS who received thrombolysis. Patients were excluded if they were transferred to another facility, if they were transitioned to comfort care or hospice care within 24 h, or if they lacked imaging and National Institutes of Health Stroke Scale (NIHSS) score data. The primary end point was incidence of sICH between 0-12 and 12-24 h. Secondary end points included the need for ICU intervention and rates of neurological deterioration. RESULTS: The analysis included 204 patients who received the full dose of alteplase. Among them, ten patients (4.9%) developed sICH, with the majority (n = 7) occurring within 12 h post-thrombolysis. Sixty-two patients required ICU interventions within 12 h compared with four patients after 12 h. Twenty-four patients had neurological deterioration within 12 h, and seven patients had neurological deterioration after 12 h. Multivariable analysis identified mechanical thrombectomy and increased blood pressure at presentation as predictors of ICU need beyond 12 h post-thrombolysis. CONCLUSIONS: Our study demonstrates that sICH, neurological deterioration, and need for ICU intervention rarely occur beyond 12 h after thrombolytic administration. Patients presenting with blood pressures < 140/90 mm Hg, NIHSS scores < 10, and not undergoing mechanical thrombectomy may be best candidates for early de-escalation. Larger prospective studies are needed to more fully evaluate the safety, feasibility, and financial impact of early transition out of the ICU.

Anemonefish are better taxonomists than humans.

The symbiosis between giant sea anemones, algae of the family Symbiodiniaceae, and anemonefish is an iconic example of a mutualistic trio1,2. Molecular analyses have shown that giant sea anemones hosting anemonefish belong to three clades: Entacmaea, Stichodactyla, and Heteractis3,4,5 (Figure 1A). Associations among 28 species of anemonefish and 10 species of giant sea anemone hosts are complex. Some fish species are highly specialized to only one anemone species (e.g., Amphiprion frenatus with Entacmaea quadricolor), whereas others are more generalist (e.g., Amphiprion clarkii)1,2,6. Reasons for host preferences are obscured, among other things, by the lack of resolution in the giant sea anemone phylogeny. Here, we generated a transcriptomic dataset from 55 sea anemones collected from southern Japan to reconstruct these phylogenetic relationships. We observed that the bubble-tip sea anemone E. quadricolor, currently considered a single species, can be separated into at least four cryptic lineages (A-D). Surprisingly, these lineages can be precisely distinguished by observing their association with anemonefish: A. frenatus only associates with lineage D, whereas A. clarkii lives in the other three lineages.

Abundance and distribution of marine litter on the beaches of Okinawa Island, Japan.

This study evaluated the distribution and abundance of marine litter on 30 beaches around Okinawa Island, Japan. Beach quality indices and multivariate statistical analyses were used to assess the quality of the beaches and their pollution patterns. A total of 11,626 items weighing 513.49 kg with an average density of 0.13 ± 0.10 items/m2 were collected. Litter was dominated by plastics (81.72 %), broken glass (8.38 %), and cigarette butts (7.44 %), and 74.05 % of total litter was from land-based sources. Single-use plastics (SUPs) were present in all surveyed beaches and made up 30.54 % of the total litter. The clean coast index (CCI), plastic abundance index (PAI), and hazardous index (HI) were between 0.1 and 7.6, 0.1-4.0 and 0.01-1.42, respectively, indicating low to moderate levels of pollution of Okinawan beaches. This study should aid in the formation of strategies to deal with marine litter in Okinawa, other areas of Japan and the Asia-Pacific region.

Genome sizes and repeatome evolution in zoantharians (Cnidaria: Hexacorallia: Zoantharia).

Across eukaryotes, large variations of genome sizes have been observed even between closely related species. Transposable elements as part of the repeated DNA have been proposed and confirmed as one of the most important contributors to genome size variation. However, the evolutionary implications of genome size variation and transposable element dynamics are not well understood. Together with phenotypic traits, they are commonly referred to as the "C-value enigma". The order Zoantharia are benthic cnidarians found from intertidal zones to the deep sea, and some species are particularly abundant in coral reefs. Despite their high ecological relevance, zoantharians have yet to be largely studied from the genomic point of view. This study aims at investigating the role of the repeatome (total content of repeated elements) in genome size variations across the order Zoantharia. To this end, whole-genomes of 32 zoantharian species representing five families were sequenced. Genome sizes were estimated and the abundances of different repeat classes were assessed. In addition, the repeat overlap between species was assessed by a sequence clustering method. The genome sizes in the dataset varied up to 2.4 fold magnitude. Significant correlations between genome size, repeated DNA content and transposable elements, respectively (Pearson's correlation test R2 = 0.47, p = 0.0016; R2 = 0.22, p = 0.05) were found, suggesting their involvement in the dynamics of genome expansion and reduction. In all species, long interspersed nuclear elements and DNA transposons were the most abundant identified elements. These transposable elements also appeared to have had a recent expansion event. This was in contrast to the comparative clustering analysis which revealed species-specific patterns of satellite elements' amplification. In summary, the genome sizes of zoantharians likely result from the complex dynamics of repeated elements. Finally, the majority of repeated elements (up to 70%) could not be annotated to a known repeat class, highlighting the need to further investigate non-model cnidarian genomes. More research is needed to understand how repeated DNA dynamics relate to zoantharian evolution and their biology.

Coral assemblages at higher latitudes favor short-term potential over long-term performance.

The persistent exposure of coral assemblages to more variable abiotic regimes is assumed to augment their resilience to future climatic variability. Yet, while the determinants of coral population resilience across species remain unknown, we are unable to predict the winners and losers across reef ecosystems exposed to increasingly variable conditions. Using annual surveys of 3171 coral individuals across Australia and Japan (2016-2019), we explore spatial variation across the short- and long-term dynamics of competitive, stress-tolerant, and weedy assemblages to evaluate how abiotic variability mediates the structural composition of coral assemblages. We illustrate how, by promoting short-term potential over long-term performance, coral assemblages can reduce their vulnerability to stochastic environments. However, compared to stress-tolerant, and weedy assemblages, competitive coral taxa display a reduced capacity for elevating their short-term potential. Accordingly, future climatic shifts threaten the structural complexity of coral assemblages in variable environments, emulating the degradation expected across global tropical reefs.

Building consensus around the assessment and interpretation of Symbiodiniaceae diversity.

Within microeukaryotes, genetic variation and functional variation sometimes accumulate more quickly than morphological differences. To understand the evolutionary history and ecology of such lineages, it is key to examine diversity at multiple levels of organization. In the dinoflagellate family Symbiodiniaceae, which can form endosymbioses with cnidarians (e.g., corals, octocorals, sea anemones, jellyfish), other marine invertebrates (e.g., sponges, molluscs, flatworms), and protists (e.g., foraminifera), molecular data have been used extensively over the past three decades to describe phenotypes and to make evolutionary and ecological inferences. Despite advances in Symbiodiniaceae genomics, a lack of consensus among researchers with respect to interpreting genetic data has slowed progress in the field and acted as a barrier to reconciling observations. Here, we identify key challenges regarding the assessment and interpretation of Symbiodiniaceae genetic diversity across three levels: species, populations, and communities. We summarize areas of agreement and highlight techniques and approaches that are broadly accepted. In areas where debate remains, we identify unresolved issues and discuss technologies and approaches that can help to fill knowledge gaps related to genetic and phenotypic diversity. We also discuss ways to stimulate progress, in particular by fostering a more inclusive and collaborative research community. We hope that this perspective will inspire and accelerate coral reef science by serving as a resource to those designing experiments, publishing research, and applying for funding related to Symbiodiniaceae and their symbiotic partnerships.

Review of microplastics in museum specimens: An under-utilized tool to better understand the Plasticene.

This study summarises the status of microplastic research in marine and freshwater specimens in natural museum collections around the world. Abundances, distributions, and types of microplastics in the archived collections are discussed. Museum collections can fill knowledge gaps on evolution of microplastic pollution before and during the Plasticene era. The specimens in these studies, ranging from plankton to vertebrates, were collected and archived between 1900 and 2019, and are dominated by specimens from marine ecosystems. All the specimens included in this review were preserved by freezing or in ethanol/formaldehyde except for specimens in one study that were preserved via cryomilling. Microfibers were the most common microplastics in the reviewed studies. We recommend more microplastic studies over a wider taxonomic range of species and across a longer span of years utilizing archival specimen collections around the world in order to establish reference points and develop temporal trends for microplastic pollution of the environment.

Morphological and phylogenetic study of Acanthosquilla Manning, 1963 (Stomatopoda: Nannosquillidae) mantis shrimps, with description of two new species from the Ryukyu Islands, Japan.

Three species of nannosquillid mantis shrimps, including two new species, Acanthosquilla ryukyuensis n. sp. and Acanthosquilla shoheii n. sp., are described based on specimens collected from the Ryukyu Islands, Japan. The two new species resemble A. derijardi Manning, 1970, but can be distinguished from A. derijardi by the following features: 1) rostral plate anterolateral corner forms almost a right angle; 2) the distal tip of the antennular somite dorsal process reaches or slightly falls short of proximal half of rostral plate; and 3) eighth thoracic somite (= TS8) posterior margin is black medially. Furthermore, A. ryukyuensis n. sp. and A. shoheii n. sp. are easy to identify by the bifurcated lateral tooth of the telson, and by the posterodorsal pattern of the telson, respectively. In this study, molecular analyses based on partial sequences of mitochondrial 12S and 16S ribosomal DNA, cytochrome oxidase subunit I (COI), and the partial nuclear gene of 28S ribosomal DNA recovers these three species of Acanthosquilla and A. multifasciata (Wood-Mason, 1895) (the type species of the genus) in a single clade. The resulting trees also suggest the polyphyly of Nannosquillidae but with low nodal support. Detailed examinations of the morphological and color features and DNA barcoding results allowed us to delineate intraspecific variations and interspecific differences. The number and shape of setae under the dorsal spine of raptorial claw carpus was found to be useful in distinguishing A. shoheii n. sp. from A. derijardi and A. ryukyuensis n. sp., while combinations of the coloration of the rostral plate, posterior margin of TS8 and posterodorsal surface of telson are useful to distinguish the three species.

Temperate functional niche availability not resident-invader competition shapes tropicalisation in reef fishes.

Temperate reefs are at the forefront of warming-induced community alterations resulting from poleward range shifts. This tropicalisation is exemplified and amplified by tropical species' invasions of temperate herbivory functions. However, whether other temperate ecosystem functions are similarly invaded by tropical species, and by what drivers, remains unclear. We examine tropicalisation footprints in nine reef fish functional groups using trait-based analyses and biomass of 550 fish species across tropical to temperate gradients in Japan and Australia. We discover that functional niches in transitional communities are asynchronously invaded by tropical species, but with congruent invasion schedules for functional groups across the two hemispheres. These differences in functional group tropicalisation point to habitat availability as a key determinant of multi-species range shifts, as in the majority of functional groups tropical and temperate species share functional niche space in suitable habitat. Competition among species from different thermal guilds played little part in limiting tropicalisation, rather available functional space occupied by temperate species indicates that tropical species can invade. Characterising these drivers of reef tropicalisation is pivotal to understanding, predicting, and managing marine community transformation.

Macroalgae exhibit diverse responses to human disturbances on coral reefs.

Scientists and managers rely on indicator taxa such as coral and macroalgal cover to evaluate the effects of human disturbance on coral reefs, often assuming a universally positive relationship between local human disturbance and macroalgae. Despite evidence that macroalgae respond to local stressors in diverse ways, there have been few efforts to evaluate relationships between specific macroalgae taxa and local human-driven disturbance. Using genus-level monitoring data from 1205 sites in the Indian and Pacific Oceans, we assess whether macroalgae percent cover correlates with local human disturbance while accounting for factors that could obscure or confound relationships. Assessing macroalgae at genus level revealed that no genera were positively correlated with all human disturbance metrics. Instead, we found relationships between the division or genera of algae and specific human disturbances that were not detectable when pooling taxa into a single functional category, which is common to many analyses. The convention to use percent cover of macroalgae as an indication of local human disturbance therefore likely obscures signatures of local anthropogenic threats to reefs. Our limited understanding of relationships between human disturbance, macroalgae taxa, and their responses to human disturbances impedes the ability to diagnose and respond appropriately to these threats.

A Draft Genome Sequence of Dorometra sesokonis (Antedonidae, Comatulida, Crinoidea, Echinodermata).

We present the complete genome sequence of Dorometra sesokonis. Genome sequencing was performed on genetic material from a single wild-collected individual. The sequence reads were assembled using a de novo method followed by a finishing step. The raw and assembled data are publicly available via GenBank.

The Complete Genome Sequences of 7 Species of Epizoanthus (Epizoanthidae, Zoantharia, Hexacorallia, Cnidaria).

We present the complete genome sequences of 7 species of the zoantharian genus Epizoanthus. Illumina sequencing was performed on genetic material from single wild-collected individuals. The reads were assembled using a de novo method followed by a finishing step. The raw and assembled data are publicly available via GenBank.

The Complete Genome Sequences of 13 Species of Brachycnemina (Cnidaria, Hexacorallia, Anthozoa, Zoantharia).

We present the complete genome sequences of 13 species of the zoantharian suborder Brachycnemina (Haddon, and Shackleton, 1891; Poliseno et al., 2020). Genome sequencing was performed on genetic material from single wild-collected individuals. For each species the sequence reads were assembled using a de novo method followed by a finishing step. The raw and assembled data are publicly available via GenBank.

Evolutionary patterns of host switching, lifestyle mode, and the diversification history in symbiotic zoantharians.

Symbioses play important roles in forming the structural and distributional patterns of marine diversity. Understanding how interspecies interactions through symbioses contribute to biodiversity is an essential topic. Host switching has been considered as one of the main drivers of diversification in symbiotic systems. However, its process and patterns remain poorly investigated in the marine realm. Hexacoral species of the order Zoantharia (=zoantharians) are often epizoic on other marine invertebrates and generally use specific taxa as hosts. The present study investigates the patterns of host switching and the diversification history of zoantharians based on the most comprehensive molecular phylogenetic analyses to date, using sequences from three mitochondrial and three nuclear markers from representatives of 27 of 29 genera. Our results indicate that symbiotic zoantharians, in particular those within suborder Macrocnemina, diversified through repeated host switching. In addition, colonization of new host taxa appears to have driven morphological and ecological specialization in zoantharians. These findings have important implications for understanding the role of symbioses in the morphological and ecological evolution of marine invertebrates.

Sexual Reproduction in Zoanthus kuroshio and Isaurus tuberculatus (Cnidaria: Anthozoa: Zoanthidae) in Southern Japan.

Among family Zoanthidae (Anthozoa: Hexacorallia: Zoantharia), Zoanthus and Isaurus are widespread benthos on coral reefs, but the reproductive biology of both genera is generally unknown. Accordingly, sexual reproduction of two Zoanthidae species in Japan, Zoanthus kuroshio in Okinawa, and Isaurus tuberculatus in Okinawa and Kochi, was investigated by annual sampling. Between 2012 and 2013, polyps of tagged colonies of Z. kuroshio and I. tuberculatus were sampled monthly, and gonads in mesenteries were examined under a stereomicroscope. In Z. kuroshio, sizes of oocytes were estimated and in situ spawning observations were conducted at night at Okinawa sites. Monthly sampling indicated that gametogenesis periods of both species in Okinawa were from May to August, and oogenesis set in earlier than spermatogenesis, and thus both species can be considered protogynous functional hermaphrodites. On the other hand, I. tuberculatus in Kochi had hermaphroditic polyps in July and August. Notably, fertile colonies of Z. kuroshio were not only hermaphrodites but also included exclusively male and female colonies. Overall, four sexual types were identified in Z. kuroshio: male, female, functional protogynous hermaphrodites, and unclassified sterile colonies. In situ gamete release of Z. kuroshio was observed in August 2012 and July to August 2013. First spawning of the year occurred 1 day after the new moon; colonies shed their bundles 3.5-4 h after sunset. We speculate that lunar phase and time after sunset influence spawning timing in Z. kuroshio. Basic knowledge on sexual reproduction of Zoanthidae is critically needed to better understand the basic biology of these benthic cnidarians.

Shallow epifaunal sea cucumber densities and their relationship with the benthic community in the Okinawa Islands.

Sea cucumbers are important ecological engineers in marine ecosystems. However, the fishery demand of some species, especially large-epifaunal and commercially used (LEC) sea cucumbers, has risen drastically, resulting in serious depletion of local populations for many species. Despite this problem, basic ecological data on sea cucumbers, such as population densities and preferred habitats, are often still insufficient. Here, we report on the population densities of multiple LEC sea cucumber species, and their ambient benthic communities at eight sites around Okinawa Islands. Further, we discuss the correspondence between sea cucumber densities and the surrounding coral communities. Our results show two sites within national or quasi-national parks, Aka and Manza, where stricter rules have been placed on fisheries and land reclamation compared to other areas, had the highest and third highest sea cucumber population densities among sites, respectively. Holothuria atra was observed at all survey sites and made up the majority of sea cucumber populations at all sites except for Chatan and Sesoko, where Holothuria leucospilota and Stichopus chloronotus were most abundant, respectively. Regarding the relationships between benthic composition and LEC sea cucumber species, S. chloronotus was significantly correlated with dead corals, scleractinian corals, and coralline algae. As well, H. leucospilota had significant correlations with rubble. Although there were no significant correlations between any specific scleractinian coral genus and sea cucumber densities, S. chloronotus was marginally insignificant with Platygyra and Psammocora. Notably, medium- to highly valued species were sparse in our surveys, and most of them appeared at only one site. Additionally, at one site (Odo), only three LEC sea cucumber individuals were observed. Combining these facts with relatively low population densities around the Okinawa Islands compared to densities reported in previous research from the Indo-West Pacific Ocean region, we conclude that Okinawan LEC sea cucumber populations have been and are being impacted by high levels of direct (e.g., overexploitation, as well as coastal development) and indirect anthropogenic pressure (e.g., decreasing water quality). To address the current situation, repeated monitoring and more detailed investigations to reveal the drivers that determine LEC sea cucumber species aggregations and population densities are urgently needed, along with more robust management of remaining LEC sea cucumber populations.

Colour patterns influence symbiosis and competition in the anemonefish-host anemone symbiosis system.

Colour patterns in fish are often used as an important medium for communication. Anemonefish, characterized by specific patterns of white bars, inhabit host anemones and defend the area around an anemone as their territory. The host anemone is used not only by the anemonefish, but also by other fish species that use anemones as temporary shelters. Anemonefish may be able to identify potential competitors by their colour patterns. We first examined the colour patterns of fish using host anemones inhabited by Amphiprion ocellaris as shelter and compared them with the patterns of fish using surrounding scleractinian corals. There were no fish with bars sheltering in host anemones, although many fish with bars were found in surrounding corals. Next, two fish models, one with white bars and the other with white stripes on a black background, were presented to an A. ocellaris colony. The duration of aggressive behaviour towards the bar model was significantly longer than that towards the stripe model. We conclude that differences in aggressive behaviour by the anemonefish possibly select the colour patterns of cohabiting fish. This study indicates that colour patterns may influence not only intraspecific interactions but also interspecific interactions in coral reef ecosystems.

Exploring the trends of adaptation and evolution of sclerites with regards to habitat depth in sea pens.

Octocorals possess sclerites, small elements comprised of calcium carbonate (CaCO3) that are important diagnostic characters in octocoral taxonomy. Among octocorals, sea pens comprise a unique order (Pennatulacea) that live in a wide range of depths. Habitat depth is considered to be important in the diversification of octocoral species, but a lack of information on sea pens has limited studies on their adaptation and evolution across depth. Here, we aimed to reveal trends of adaptation and evolution of sclerite shapes in sea pens with regards to habitat depth via phylogenetic analyses and ancestral reconstruction analyses. Colony form of sea pens is suggested to have undergone convergent evolution and the loss of axis has occurred independently across the evolution of sea pens. Divergences of sea pen taxa and of sclerite forms are suggested to depend on habitat depths. In addition, their sclerite forms may be related to evolutionary history of the sclerite and the surrounding chemical environment as well as water temperature. Three-flanged sclerites may possess the tolerance towards the environment of the deep sea, while plate sclerites are suggested to be adapted towards shallower waters, and have evolved independently multiple times. The common ancestor form of sea pens was predicted to be deep-sea and similar to family Pseudumbellulidae in form, possessing sclerites intermediate in form to those of alcyonaceans and modern sea pens such as spindles, rods with spines, and three-flanged sclerites with serrated edges sclerites, as well as having an axis and bilateral traits.

Diversity and distribution of air-breathing sea slug genus Peronia Fleming, 1822 (Gastropoda: Onchidiidae) in southern Japanese waters.

Species of the genus Peronia Fleming, 1822, are air-breathing onchidiid sea slugs that inhabit intertidal reef flats of temperate to tropical zones. In the Ryukyu Islands of southern subtropical Japan, Peronia species are a traditional food source for local people. To date, there have been three species recorded around Okinawajima Island; P. verruculata and P. peronii, along with recently described P. okinawensis, which was described as possibly endemic to Okinawajima Island. This study aimed to map the distribution ranges of these three Peronia species within the Ryukyu Islands using molecular analyses in order to understand the specific distribution of each species. Since Peronia species are generally indistinguishable by gross external morphology, a DNA barcoding approach was employed to identify specimens. The molecular data showed that there are four species present in the Ryukyu Islands. P. verruculata (unit #1 sensu Dayrat et al., 2020) was dominant at almost all locations, while P. peronii was present in much lower numbers than P. verruculata, but found across a relatively wide range in the Ryukyu Islands. We newly record P. okinawensis and P. setoensis from Amami Oshima Island and from several places around Okinawajima Island, and also identified high levels of genetic variation within P. setoensis. Peronia okinawensis and P. setoensis have been thought to be endemic to Okinawajima Island and to Honshu, mainland Japan, respectively. However, as both species were observed around Okinawajima and Amami Oshima islands, other islands of the Ryukyus are also likely to harbor these species, and their distribution ranges are wider than previously thought. Based on the results from molecular analyses, we provide general descriptions of each species. Sizes of specimens were consistently smaller for P. setoensis and relatively larger for P. peronii specimens. On the other hand, P. verruculata and P. okinawensis had similar size ranges, but P. okinawensis had comparatively much more distinct papillae. This study revealed that the Ryukyu Islands are the only region currently known with four sympatric Peronia species, and this work provides a basis for future research on these Peronia species throughout the northwest Pacific Ocean, representing the first step in more effective management of the local Peronia fisheries in the Ryukyu Islands.