324 research outputs found

    Strongholds of Ostrea edulis populations in estuaries in Essex, SE England and their association with traditional oyster aquaculture: evidence to support a MPA designation

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    The flat oyster Ostrea edulis has declined significantly in European waters since the 1850s as a result of anthropogenic activity. Ostrea edulis was designated a UK Biodiversity Action Plan Species and Habitat in 1995, and as a Feature of Conservation Importance (FOCI) within the UK Marine & Coastal Access Act 2009. To promote the recovery of oyster beds, a greater understanding of its abundance and distribution is required. Distribution of O. edulis across the proposed Blackwater, Crouch, Roach and Colne MCZ in Essex was determined between 2008 and 2012. Ostrea edulis were present in four estuary zones; with highest sample abundance in the Blackwater and Ray Sand zones. Size structure of populations varied, with the Ray Sand and Colne zones showing a significant lack of individuals with shell height <39 mm. Ostrea edulis occurred in highest number on shell substratum, followed by silty sediments. There were no significant associations between O. edulis abundance or size structure with water column Chl a, suspended solids, oxygen, nitrate or ammonium concentrations, temperature or pH. Highest abundance and most equitable population shell-size distribution for O. edulis were located within, or adjacent to, actively managed aquaculture zones. This suggests that traditional seabed management contributed to the maintenance or recovery of the species of conservation concern. Demonstration that the Essex estuaries were a stronghold for Ostrea edulis in the southern North sea area led to the designation of the Blackwater, Crouch, Roach and Colne estuaries Marine Conservation Zone in 2013

    Acropora - The most-studied coral genus

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    Over the last 2 million years, Acropora (the staghorn or elkhorn corals) has become the dominant genus of reef-building corals throughout the Indo-Pacific. Like other coral genera, Acropora taxonomy is presently undergoing comprehensive revision as a consequence of large-scale sequencing projects, which will substantially alter our understanding of the diversity and biogeography of the group. Acropora spp. are among the most stress sensitive of corals, and as a consequence, population declines are occurring worldwide, most significantly due to global warming. Despite diverse adult colony morphology, all members of the genus are similar at the tissue and polyp level and follow common reproductive and developmental programs. Some progress has recently been made in development of gene knockdown/knockout methods despite the long generation times of corals and need to rely on natural spawning events. Since 2018, the number of Acropora genome sequences available has increased dramatically, although taxonomic uncertainties complicate their evolutionary interpretation. Areas of particularly active research include settlement and the control of metamorphosis; metabolic interactions with both bacterial and eukaryotic symbionts, particularly Symbiodinaceae, and their gain and loss; and how best to restore reefs destroyed by storms and coral bleaching

    Senior Recital: Gage Fisher, trombone

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    This recital is presented in partial fulfillment of requirements for the degree Bachelor of Music in Performance. Mr. Fisher studies trombone with Wes Funderburk and Tom Gibson.https://digitalcommons.kennesaw.edu/musicprograms/2205/thumbnail.jp

    Performance of the Near-infrared coronagraphic imager on Gemini-South

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    We present the coronagraphic and adaptive optics performance of the Gemini-South Near-Infrared Coronagraphic Imager (NICI). NICI includes a dual-channel imager for simultaneous spectral difference imaging, a dedicated 85-element curvature adaptive optics system, and a built-in Lyot coronagraph. It is specifically designed to survey for and image large extra-solar gaseous planets on the Gemini Observatory 8-meter telescope in Chile. We present the on-sky performance of the individual subsystems along with the end-to-end contrast curve. These are compared to our model predictions for the adaptive optics system, the coronagraph, and the spectral difference imaging.Comment: Proc. SPIE, Vol. 7015, 70151V (2008

    Lactate, a product of glycolytic metabolism, inhibits histone deacetylase activity and promotes changes in gene expression

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    Chemical inhibitors of histone deacetylase (HDAC) activity are used as experimental tools to induce histone hyperacetylation and deregulate gene transcription, but it is not known whether the inhibition of HDACs plays any part in the normal physiological regulation of transcription. Using both in vitro and in vivo assays, we show that lactate, which accumulates when glycolysis exceeds the cell’s aerobic metabolic capacity, is an endogenous HDAC inhibitor, deregulating transcription in an HDAC-dependent manner. Lactate is a relatively weak inhibitor (IC(50) 40 mM) compared to the established inhibitors trichostatin A and butyrate, but the genes deregulated overlap significantly with those affected by low concentrations of the more potent inhibitors. HDAC inhibition causes significant up and downregulation of genes, but genes that are associated with HDAC proteins are more likely to be upregulated and less likely to be downregulated than would be expected. Our results suggest that the primary effect of HDAC inhibition by endogenous short-chain fatty acids like lactate is to promote gene expression at genes associated with HDAC proteins. Therefore, we propose that lactate may be an important transcriptional regulator, linking the metabolic state of the cell to gene transcription

    The 'Melanoma-enriched' microRNA miR-4731-5p acts as a tumour suppressor

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    We previously identified miR-4731-5p (miR-4731) as a melanoma-enriched microRNA following comparison of melanoma with other cell lines from solid malignancies. Additionally, miR-4731 has been found in serum from melanoma patients and expressed less abundantly in metastatic melanoma tissues from stage IV patients relative to stage III patients. As miR-4731 has no known function, we used biotin-labelled miRNA duplex pull-down to identify binding targets of miR-4731 in three melanoma cell lines (HT144, MM96L and MM253). Using the miRanda miRNA binding algorithm, all pulled-down transcripts common to the three cell lines (n=1092) had potential to be targets of miR-4731 and gene-set enrichment analysis of these (via STRING v9.1) highlighted significantly associated genes related to the ‘cell cycle’ pathway and the ‘melanosome’. Following miR-4731 overexpression, a selection (n=81) of pull-down transcripts underwent validation using a custom qRT-PCR array. These data revealed that miR-4731 regulates multiple genes associated with the cell cycle (e.g. CCNA2, ORC5L, and PCNA) and the melanosome (e.g. RAB7A, CTSD, and GNA13). Furthermore, members of the synovial sarcoma X breakpoint family (SSX) (melanoma growth promoters) were also down-regulated (e.g. SSX2, SSX4, and SSX4B) as a result of miR-4731 overexpression. Moreover, this down-regulation of mRNA expression resulted in ablation or reduction of SSX4 protein, which, in keeping with previous studies, resulted in loss of 2D colony formation. We therefore speculate that loss of miR-4731 expression in stage IV patient tumours supports melanoma growth by, in part; reducing its regulatory control of SSX expression levels

    Functionally distinct T-helper cell phenotypes predict resistance to different types of parasites in a wild mammal

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    The adaptive immune system is critical to an effective response to infection in vertebrates, with T-helper (Th) cells pivotal in orchestrating these responses. In natural populations where co-infections are the norm, different Th responses are likely to play an important role in maintaining host health and fitness, a relationship which remains poorly understood in wild animals. In this study, we characterised variation in functionally distinct Th responses in a wild population of Soay sheep by enumerating cells expressing Th-subset specific transcription factors and quantifying Th-associated cytokines. We tested the prediction that raised Th1 and Th2 responses should predict reduced apicomplexan and helminth parasite burdens, respectively. All measures of Th-associated cytokine production increased with age, while Th17- and regulatory Th-associated cytokine production increased more rapidly with age in males than females. Independent of age, sex, and each other, IL-4 and Gata3 negatively predicted gastro-intestinal nematode faecal egg count, while IFN-γ negatively predicted coccidian faecal oocyst count. Our results provide important support from outside the laboratory that Th1 and Th2 responses predict resistance to different kinds of parasites, and illustrate how harnessing specific reagents and tools from laboratory immunology will illuminate our understanding of host-parasite interactions in the wild

    Duration of vaccine effectiveness against SARS-CoV-2 infection, hospitalisation, and death in residents and staff of long-term care facilities in England (VIVALDI): a prospective cohort study

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    Background: Residents and staff in long-term care facilities have been prioritised for vaccination against SARS-CoV-2, but data on potential waning of vaccine effectiveness and the effect of booster doses in this vulnerable population are scarce. We aimed to evaluate effectiveness of one, two, and three vaccine doses against infection and severe clinical outcomes in staff and residents of long-term care facilities in England over the first year following vaccine roll-out. Methods: The VIVALDI study is a prospective cohort study done in 331 long-term care facilities in England. Residents aged 65 years or older and staff aged 18 years or older were eligible for participation. Participants had routine PCR testing throughout the study period between Dec 8, 2020, and Dec 11, 2021. We retrieved all PCR results and cycle threshold values for PCR-positive samples from routine testing in long-term care facilities, and positive PCR results from clinical testing in hospitals through the UK's COVID-19 Datastore. PCR results were linked to participants using pseudo-identifiers based on individuals' unique UK National Health Service (NHS) numbers, which were also used to retrieve vaccination records from the National Immunisation Management Service, hospitalisation records from NHS England, and deaths data from the Office for National Statistics through the COVID-19 Datastore. In a Cox proportional hazards regression, we estimated vaccine effectiveness against SARS-CoV-2 infection, COVID-19-related hospitalisation, and COVID-19-related death after one, two, and three vaccine doses, separately by previous SARS-CoV-2 exposure. This study is registered with the ISRCTN Registry, ISRCTN 14447421. Findings: 80 186 residents and staff of long-term care facilities had records available for the study period, of whom 15 518 eligible residents and 19 515 eligible staff were included in the analysis. For residents without evidence of previous SARS-CoV-2 exposure, vaccine effectiveness decreased from 61·7% (95% CI 35·1 to 77·4) to 22·0% (–14·9 to 47·0) against infection; from 89·0% (70·6 to 95·9) to 56·3% (30·1 to 72·6) against hospitalisation; and from 96·4% (84·3 to 99·2) to 64·4% (36·1 to 80·1) against death, when comparing 14–83 days after dose two and 84 days or more after dose two. For staff without evidence of previous exposure, vaccine effectiveness against infection decreased slightly from 57·9% (43·1 to 68·9) at 14–83 days after dose two to 42·1% (29·9 to 52·2) at 84 days or more after dose two. There were no hospitalisations or deaths among unexposed staff at 14–83 days, but seven hospitalisations (vaccine effectiveness 91·0% [95% CI 74·3 to 96·8]) and one death were observed at 84 days or more after dose two. High vaccine effectiveness was restored following a third vaccine dose, with vaccine effectiveness in unexposed residents of 72·7% (55·8 to 83·1) against infection, 90·1% (80·6 to 95·0) against hospitalisation, and 97·5% (88·1 to 99·5) against death; and vaccine effectiveness in unexposed staff of 78·2% (70·0 to 84·1) against infection and 95·8% (49·9 to 99·6) against hospitalisation. There were no COVID-19-related deaths among unexposed staff after the third vaccine dose. Interpretation: Our findings showed substantial waning of SARS-CoV-2 vaccine effectiveness against all outcomes in residents of long-term care facilities from 12 weeks after a primary course of ChAdOx1-S or mRNA vaccines. Boosters restored protection, and maximised immunity across all outcomes. These findings show the importance of boosting and the need for ongoing surveillance in this vulnerable cohort
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