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8.2 ka event North Sea hydrography determined by bivalve shell stable isotope geochemistry.
2019
AbstractThe abrupt 8.2 ka cold event has been widely described from Greenland and North Atlantic records. However, its expression in shelf seas is poorly documented, and the temporal resolution of most marine records is inadequate to precisely determine the chronology of major events. A robust hydrographical reconstruction can provide an insight on climatic reaction times to perturbations to the Atlantic Meridional Overturning Circulation. Here we present an annually-resolved temperature and water column stratification reconstruction based on stable isotope geochemistry of Arctica islandica shells from the Fladen Ground (northern North Sea) temporally coherent with Greenland ice core record…
Monitoring of system conditioning after blank injections in untargeted UPLC-MS metabolomic analysis
2019
AbstractUltra-performance liquid chromatography – mass spectrometry (UPLC-MS) is widely used for untargeted metabolomics in biomedical research. To optimize the quality and precision of UPLC-MS metabolomic analysis, evaluation of blank samples for the elimination of background features is required. Although blanks are usually run either at the beginning or at the end of a sequence of samples, a systematic analysis of their effect of the instrument performance has not been properly documented. Using the analysis of two common bio-fluids (plasma and urine), we describe how the injection of blank samples within a sequence of samples may affect both the chromatographic and MS detection performa…
mRNA-Based Vaccines
2021
Increases in the world’s population and population density promote the spread of emerging pathogens. Vaccines are the most cost-effective means of preventing this spread. Traditional methods used to identify and produce new vaccines are not adequate, in most instances, to ensure global protection. New technologies are urgently needed to expedite large scale vaccine development. mRNA-based vaccines promise to meet this need. mRNA-based vaccines exhibit a number of potential advantages relative to conventional vaccines, namely they (1) involve neither infectious elements nor a risk of stable integration into the host cell genome; (2) generate humoral and cell-mediated immunity; (3) are well-t…
Everolimus as first line therapy for pancreatic neuroendocrine tumours: current knowledge and future perspectives
2017
urpose Everolimus has been shown to be effective for advanced pancreatic neuroendocrine tumours (pNETs), but its positioning in the therapeutic algorithm for pNETs is matter of debate. Methods With the aim to shed light on this point, we performed an up-to-date critical review taking into account the results of both retrospective and prospective published studies, and the recommendations of international guidelines. In addition, we performed an extensive search on the Clinical Trial Registries databases worldwide, to gather information on the ongoing clinical trials related to this specific topic. Results We identified eight retrospective published studies, two prospective published studies…
Magnetite Nanoparticles Prepared By Spark Erosion
2016
Abstract In the present research, we study a possibility of using the electric spark erosion method as an alternative to the method of chemical co-precipitation for preparation of magnetic nanoparticles. Initiation of high frequency electric discharge between coarse iron particles under a layer of distilled water allows obtaining pure magnetite nanoparticles.
Fungal community assemblage of different soil compartments in mangrove ecosystem
2017
AbstractThe fungal communities of different soil compartments in mangrove ecosystem are poorly studied. We sequenced the internal transcribed spacer (ITS) regions to characterize the fungal communities in Avicennia marina root-associated soils (rhizosphere and pneumatophore) and bulk soil compartments. The rhizosphere but not pneumatophore soil compartment had significantly lower fungal species richness than bulk soil. However, bulk soil fungal diversity (Shannon diversity index) was significantly higher than both pneumatophore and rhizosphere soil compartments. The different soil compartments significantly affected the fungal community composition. Pairwise sample analyses showed that bulk…
The swinholide biosynthesis gene cluster from a terrestrial cyanobacterium, Nostoc sp. strain UHCC 0450
2017
ABSTRACT Swinholides are 42-carbon ring polyketides with a 2-fold axis of symmetry. They are potent cytotoxins that disrupt the actin cytoskeleton. Swinholides were discovered from the marine sponge Theonella sp. and were long suspected to be produced by symbiotic bacteria. Misakinolide, a structural variant of swinholide, was recently demonstrated to be the product of a symbiotic heterotrophic proteobacterium. Here, we report the production of swinholide A by an axenic strain of the terrestrial cyanobacterium Nostoc sp. strain UHCC 0450. We located the 85-kb trans -AT polyketide synthase (PKS) swinholide biosynthesis gene cluster from a draft genome of Nostoc sp. UHCC 0450. The swinholide …
A Role of Histone Acetylation in the Regulation of Circadian Rhythm in Ants
2020
Summary In many organisms, circadian rhythms and associated oscillations in gene expression are controlled by post-translational modifications of histone proteins. Although epigenetic mechanisms influence key aspects of insect societies, their implication in regulating circadian rhythms has not been studied in social insects. Here we ask whether histone acetylation plays a role in adjusting circadian activity in the ant Temnothorax longispinosus. We characterized activity patterns in 20 colonies to reveal that these ants exhibit a diurnal rhythm in colony-level activity and can rapidly respond to changes in the light regime. Then we fed T. longispinosus colonies with C646, a chemical inhibi…
Natural visibility graphs for diagnosing attention deficit hyperactivity disorder (ADHD)
2016
“NOTICE: this is the author’s version of a work that was accepted for publication in Electronic Notes in Discrete Mathematics. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Electronic Notes in Discrete Mathematics, [Volume 54, October 2016, Pages 337-342] DOI 10.1016/j.endm.2016.09.058 ¨
A Two-Component regulatory system with opposite effects on glycopeptide antibiotic biosynthesis and resistance
2020
AbstractThe glycopeptide A40926, produced by the actinomycete Nonomuraea gerenzanensis, is the precursor of dalbavancin, a second-generation glycopeptide antibiotic approved for clinical use in the USA and Europe in 2014 and 2015, respectively. The final product of the biosynthetic pathway is an O-acetylated form of A40926 (acA40926). Glycopeptide biosynthesis in N. gerenzanensis is dependent upon the dbv gene cluster that encodes, in addition to the two essential positive regulators Dbv3 and Dbv4, the putative members of a two-component signal transduction system, specifically the response regulator Dbv6 and the sensor kinase Dbv22. The aim of this work was to assign a role to these two ge…