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Biology subjects

Devereux, M.

Publications and source records attributed to Devereux, M..

4 recordsLinked to original sources

Engineering NIR probes to enhance affinity and clinical workflow compatibility for prostate cancer imaging

Positive surgical margins following radical prostatectomy increase the risk of biochemical recurrence and subsequent disease progression. Fluorescence guided surgery (FGS) using targeted contrast agents has shown clinical benefits for several cancer types. However, current prostate cancer targeted imaging probes exhibit long pharmacokinetic (PK) profiles, necessitating extended waiting periods or repeated hospital visits, limiting their integration into standard clinical workflow. To overcome this critical clinical compatibility challenge, we developed an innovative tri-compartment, chemistry-driven probe design strategy. Specifically, we developed a congeneric library of near infrared (NIR) water soluble fluorescent probes incorporating: (1) a glutamic acid-urea-lysine (EuK) ligand targeting prostate specific membrane antigen (PSMA); (2) a NIR heptamethine cyanine fluorophore optimized for enhanced PSMA binding via secondary binding sites interactions; and (3) distinct PK modulators residing outside the PSMA binding pocket to promote rapid off-target tissue clearance. While molecular docking scores, photophysical properties and live-cell staining results showed similar overall performance, probes bearing PK modulators produced stronger tumor-specific fluorescence in vivo than the control lacking a PK modulator. This effort enabled identification of a lead probe with robust tumor targeting and accelerated off-target clearance, providing optimal tumor-specific signal and contrast in a timeframe, fully compatible with robotic-assisted radical prostatectomy (RARP) timelines.

pharmacology and toxicology↗

Synergistic Cytotoxicity Between Cold Atmospheric Plasma and Pyrazolopyrimidinones Against Glioblastoma Cells

Pyrazolopyrimidinone is a fused nitrogen-containing heterocyclic system, which acts as a core scaffold in many pharmaceutically relevant compounds. Pyrazolopyrimidinones have been demonstrated to be efficient in treating several diseases, including cystic fibrosis, obesity, viral infection and cancer. We have tested the synergistic anti-cancer effects of 15 pyrazolopyrimidinones, synthesised in a two-step process, combined with cold atmospheric plasma (CAP), a novel innovation generating reactive species with other unique chemical and physical effects. We identify two pyrazolopyrimidinones that act as prodrugs and display enhanced reactive-species dependent cytotoxicity when used in combination with cold atmospheric plasma. Synergistic activation was evident for both direct CAP treatment on prodrug loaded tumour cells and indirect CAP treatment of prodrug in media prior to adding to tumour cells. Our results demonstrate the potential of CAP combined with pyrazolopyrimidinones as a programmable cytotoxic therapy against cancer. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=113 SRC="FIGDIR/small/429831v1_ufig1.gif" ALT="Figure 1"> View larger version (47K): org.highwire.dtl.DTLVardef@56c8aeorg.highwire.dtl.DTLVardef@1913ea9org.highwire.dtl.DTLVardef@a8f522org.highwire.dtl.DTLVardef@75a529_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

Deciphering trophic interactions in a mid-Cambrian assemblage

The Cambrian Period (541-485 Mya) represents a major stage in the development of metazoan-dominated assemblages with complex community structure and species interactions. Exceptionally preserved fossil sites have allowed specimen-based identification of putative trophic interactions to which network analyses have been applied. However, network analyses of the fossil record suffer from incomplete and indirect data, time averaging that obscures species coexistence, and biases in preservation. Here, we present a novel high-resolution fossil dataset from the Raymond Quarry (RQ) member of the mid-Cambrian Burgess Shale (7549 specimens, 61 taxa, ~510 Mya) affording new perspectives on these challenging issues. Further, we formulate a new measure of preservation bias that aids identification of those assemblage subsets to which network analyses can be reliably applied. For sections with sufficiently low bias, abundance correlation network analyses predicted longitudinally consistent trophic and competitive interactions. Our correlation network analyses predicted previously postulated trophic interactions with 83.5% accuracy and demonstrated a shift from specialist interaction-dominated assemblages to ones dominated by generalist and competitive interactions. This approach provides a robust, taphonomically corrected framework to explore and predict in detail the existence and ecological character of putative interactions in fossil datasets, offering new windows on ancient food-webs. Significance StatementUnderstanding interactions in paleo-ecosystems has been a difficult task due to biases in collection and preservation of taxa, as well as low time resolution of data. In this work, we use network science tools and a fine scale dataset from the Cambrian period to explore: (i) preservation bias due to ecological/physical characteristics of taxa; (ii) evidence that the magnitude and sign of pairwise abundance correlations between two fossil taxa yields information concerning the ecological character about the interaction. All results in our work derive from using complex system approaches to analyze abundance data, without assuming any prior knowledge about species interactions - thereby providing a novel general framework to assess and explore fossil datasets.

paleontology↗

Legionella pneumophila translocated translation inhibitors are required for bacterial-induced host cell cycle arrest

The cell cycle machinery controls diverse cellular pathways and is tightly regulated. Misregulation of cell division plays a central role in the pathogenesis of many disease processes. Various microbial pathogens interfere with the cell cycle machinery to promote host cell colonization. Although cell cycle modulation is a common theme among pathogens, the role that this interference plays in promoting diseases is unclear. Previously we demonstrated that the G1 and G2/M phases of the host cell cycle are permissive for Legionella pneumophila replication, while S phase provides a toxic environment for bacterial replication. In this study we show that L. pneumophila avoids host S phase by blocking host DNA synthesis and preventing cell cycle progression into S phase. Cell cycle arrest upon Legionella contact is dependent on the Icm/Dot secretion system. In particular, we found that cell cycle arrest is dependent on the intact enzymatic activity of translocated substrates that inhibits host translation. Moreover, we show that early in infection, the presence of these translation inhibitors is crucial to induce the degradation of the master regulator cyclin D1. Our results demonstrate that the bacterial effectors that inhibit translation are associated with preventing entry of host cells into a phase associated with restriction of L. pneumophila. Furthermore, control of cyclin D1 may be a common strategy used by intracellular pathogens to manipulate the host cell cycle and promote bacterial replication.\n\nSignificanceRecently, we showed that host cell cycle regulatory proteins control L. pneumophila growth. In particular, bacterial replication was found to be depressed in S-phase. This indicates that bacterial control of the host cell cycle can limit exposure of the pathogen to antimicrobial events that are cycle-specific. Here we uncovered bacterial factors that induce host cell cycle arrest by inhibiting host protein synthesis and preventing S phase transition. These data are consistent with S-phase toxicity serving as an important antimicrobial response that limits growth of some intracellular pathogens. Moreover, identification of microbial factors that block cell cycle progression and uncovering host cell cycle partners are candidates for future drug development. Our data point to a unifying role of the cell cycle in multiple disease processes.

microbiology↗