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Campbell, J.

Publications and source records attributed to Campbell, J..

At least 19 recordsLinked to original sources

Injectable Electrospun Hydrogel with Antimicrobial, pH Sensing Nanoparticles for Local Infection Control and Monitoring

Most antimicrobial drug candidates currently in development are derivatives of established antibiotic classes. In contrast, antimicrobial heteroatom-doped carbon quantum dot (COD) nanoparticles vastly differ from their chemical antibiotic counterparts and exhibit potent antibacterial activity and favourable biocompatibility, representing a promising alternative strategy, particularly for topical applications. Here, we report the incorporation of cobalt-doped carbon quantum dots (Co-CODs) into injectable, biocompatible hydrogels capable of both sensing pH and eliminating bacteria. Ultrasmall Co-CODs demonstrated broad-spectrum activity against gram-positive Methicillin-resistant Staphylococcus aureus (MRSA) and Gram-negative Pseudomonas aeruginosa (PAO1), mediated by membrane hyperpolarisation and reactive oxygen species (ROS) induced membrane damage. The particles showed negligible effect on primary fibroblast and endothelial cell viability at concentrations that were bactericidal to MRSA. Polymeric hydrogels were fabricated via electrospinning of chitosan, polyvinylpyrrolidone (PVP), and polyvinyl alcohol (PVA) polymer blends incorporating Co-COD and pH-responsive HPTS particles. This approach provided accurate measurement of environmental pH within the physiological range observed across healthy and chronic wounds. In vivo, the injectable hydrogels exhibited robust antimicrobial efficacy against MRSA without impairing wound closure relative to untreated controls, while also reducing inflammatory immune responses in infected tissues. Collectively, these findings demonstrate the potential of ultrasmall metal-doped CODs for infection control and their integration into 3D matrices as multifunctional theragnostic platforms. ToC (<60 words describe the main results)Ultrasmall antimicrobial carbon nanoparticles were incorporated into polymeric hydrogels containing a pH-responsive probe. This platform enabled detection across a physiologically relevant pH range of 5.0-6.5, spanning conditions associated with both healthy healing and chronically infected wounds. The hydrogel demonstrated strong antibacterial activity by generating damaging reactive oxygen species, and, in mice, effectively controlled infection while reducing pro-inflammatory immune responses. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=171 SRC="FIGDIR/small/736887v1_ufig1.gif" ALT="Figure 1"> View larger version (41K): org.highwire.dtl.DTLVardef@1a52b32org.highwire.dtl.DTLVardef@b6eed2org.highwire.dtl.DTLVardef@1f94143org.highwire.dtl.DTLVardef@12b9ff3_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOScheme 1:C_FLOATNO Antimicrobial nanoparticle-doped hydrogel glows in alkaline wound conditions which are representative of chronic infections. Once in the wound bed, the hydrogel removes all MRSA infection, reducing inflammatory macrophage (iNOS) and neutrophil (MPO) populations, and restores healthy wound collagen deposition. C_FIG

bioengineering↗

Glioblastoma-derived extracellular vesicles released after radiation promote cognitive impairment through NFκB-mediated microglial activation

Glioblastoma (GBM) is the most aggressive primary brain tumor in adults. Cognitive impairment is a common sequela in glioblastoma survivors, yet the underlying mechanisms remain poorly understood. Extracellular vesicles (EVs) derived from glioblastoma are established mediators of intercellular signaling within the tumor microenvironment. Here, we investigated whether GBM-derived EVs released after radiation treatment (RT-EVs) regulate cognitive function. Treatment with RT-EVs was associated with cognitive deficits and neuroinflammatory responses in vivo. In vitro, RT-EVs activated the NF{kappa}B pathway and induced the release of neurotoxic H2O2. Importantly, NF{kappa}B p50 knockdown abolished the H2O2 release previously triggered by RT-EVs, demonstrating mechanistic dependence on NF{kappa}B signaling. Collectively, these findings identify GBM-derived RT-EVs as critical mediators of cognitive impairment through NF{kappa}B-dependent redox imbalance. EV-driven redox dysregulation may therefore represent a therapeutic target to mitigate GBM-associated cognitive dysfunction. Highlights- Radiation induces the release of glioblastoma-derived EVs that are biologically different from those released under non-irradiated conditions. - EVs released from glioblastoma after radiation are sufficient to impair cognition - EVs from irradiated glioblastoma can activate microglia via NF{kappa}B and induce production of neurotoxic H2O2 Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=52 SRC="FIGDIR/small/730969v1_ufig1.gif" ALT="Figure 1"> View larger version (11K): org.highwire.dtl.DTLVardef@e57bcborg.highwire.dtl.DTLVardef@228862org.highwire.dtl.DTLVardef@127dd13org.highwire.dtl.DTLVardef@232ddd_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

cadmus: a robust pipeline for scalable retrieval of full-text biomedical literature

cadmus is an open-source Python toolkit for automated retrieval and processing of full-text biomedical literature. It utilises programmatic access to PubMed, Crossref, Europe PMC, PMC, and publisher APIs, allowing users to construct large, domain-specific corpora with minimal manual intervention. cadmus parses PDF, HTML, XML, and plain text files, standardising them for downstream biomedical text mining. During the retrieval of a Developmental Disorders Corpus (204,043 publications), it achieved an 85.2% full-text retrieval rate with institutional subscriptions and 54.4% without. To test the fidelity of retrieved full-texts, we used ScispaCy to infer the similarity of paired documents from 44,264 open-access PubMed Central files and the files retrieved from cadmus, resulting in an average cosine similarity score of 0.98. Rarefaction analyses demonstrated that full-text corpora double the coverage of unique biomedical concepts over abstracts, resulting in better access to the depth of the biomedical information available. Availability and implementationcadmus is a freely available package for non-commercial research at https://github.com/biomedicalinformaticsgroup/cadmus and released under the MIT License.

bioinformatics↗

Obligate multicellularity circumvents population genetic barriers to collective-level adaptation

Complex multicellularity has evolved in just five lineages (animals, plants, brown algae, red algae, and fungi) and in each case, these organisms develop clonally and are obligately multicellular. While prior work has shown that clonal development plays a critical role in the evolution of complex multicellularity, none has disentangled this from the impact of obligate vs facultative multicellular life cycles. Here we use experimental evolution with engineered snowflake yeast (Saccharomyces cerevisiae) to directly test how life cycle structure affects multicellular adaptation. We created isogenic strains capable of switching between unicellular and clonal multicellular phases, then evolved populations for 192 days under obligately multicellular, facultatively multicellular, and obligately unicellular regimes. Obligately multicellular populations rapidly evolved larger size, primarily driven by a whole genome duplication, in all five replicates. Facultative populations showed dramatically constrained evolution, with tetraploidy evolving in only 2/10 facultative populations despite experiments demonstrating that it is strongly beneficial across the full life cycle. Mathematical modeling reveals the mechanistic basis for this constraint: facultative life cycles create establishment barriers through two population genetic effects. Group formation dramatically reduces the number of units of selection, making beneficial multicellular mutations vulnerable to drift. This asymmetry in population size between life cycle phases also allows cell-level selection to overpower group-level selection, eliminating mutations that provide group-level benefits but carry cell-level costs. These findings demonstrate that obligate multicellularity circumvents fundamental population genetic barriers to collective-level adaptation, helping explain why complex multicellularity has evolved exclusively in obligately multicellular lineages, and suggesting similar constraints may operate in other evolutionary transitions in individuality.

evolutionary biology↗

Non-invasive measurement of neurotransmitter-specific glucose metabolism in the human brain using proton-observed proton-edited 13C-MRS (POPE13C-MRS)

Non-invasive measurement of neurotransmitter-specific glucose metabolism in the human brain remains a major challenge, limiting mechanistic insight into excitatory-inhibitory imbalance across neurological and psychiatric disorders. Existing approaches either lack neurotransmitter specificity or require specialised hardware that constrains clinical applicability. Here, we introduce proton-observed proton-edited 13C magnetic resonance spectroscopy (POPE13C-MRS), an approach that enables non-invasive detection of glutamate, GABA, and lactate metabolism using standard proton MRI hardware. The method combines administration of 13C-labelled glucose with targeted proton editing to detect 1H-13C satellite resonances. Using a cross-species proof-of-concept approach, we demonstrate consistent detection of neurotransmitter-specific 13C labelling in mice and feasibility in the human brain at ultra-high field. POPE13C-MRS provides a readout of glutamatergic and GABAergic metabolism, enabling in vivo assessment of excitatory-inhibitory metabolic balance. This establishes a means for probing neurometabolic coupling with potential applications in translational and clinical neuroscience.

neuroscience↗

Primary cilia regulate GLP-1 signaling in pancreatic beta cells

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are mainstay therapies for diabetes and obesity, acting in part by enhancing glucose-dependent insulin secretion. While the primary cilium is a known signaling compartment for certain G-protein coupled receptors (GPCRs), its role in the {beta}-cell response to incretins remains undefined. Here, we show that primary cilia are essential for GLP-1R signaling. Loss of {beta}-cell cilia in mouse and human islets severely impaired GLP-1-potentiated insulin secretion, an effect preceded by blunted whole-cell cAMP and Ca{superscript 2} responses. Immunofluorescence and immunogold scanning electron microscopy revealed endogenous GLP-1R localized to the primary cilium. Critically, disrupting ciliary GPCR trafficking via Tulp3 knockdown - while preserving cilia structure - recapitulated the signaling and secretory deficits, demonstrating a specific requirement for the ciliary receptor pool. These findings establish the primary cilium as a non-redundant signaling compartment for GLP-1R and uncover a new layer of subcellular organization in incretin action in {beta} cells.

cell biology↗

Spatiotemporal-multimodal integration reveals BCG-induced skin-blood crosstalk

Tuberculosis (TB) remains the leading cause of infectious death. The Bacille Calmette-Guerin (BCG) vaccine has been the only licensed vaccine available for TB prevention. Despite BCG being administered intradermally for over a century to >100 million individuals annually, the molecular events in the skin following BCG administration have not been investigated; as a result, measurable correlates of protection that could predict vaccine effectiveness already early after vaccination are lacking. Here we show that BCG immediately (within one day after vaccination) induces dynamic molecular waves that drive the acute human host response across space (layers of the skin and systemically in blood) and time (days). Integration of this data across space and time identified robust networks of interactive modules related to immune surveillance (e.g. Langerhans cells), cell trafficking (e.g. endothelial cells, ITGB5), and trained immunity (e.g. neutrophils, macrophages, {gamma}{delta}-T cell). Importantly, not only were we able to identify BCG-activated pathways associated with trained immunity such as mTOR signaling and glycolysis/gluconeogenesis, we were able to pinpoint the time-point and precise location (skin layer) of the initial activation of theses pathways. Combining tissue biopsies of human skin (spatial genomics) with liquid biopsies (cell-free blood plasma RNASeq) following BCG vaccination our data both confirmed known evidence (e.g. prominent {gamma}{delta}-T cell induction at the site of BCG administration; negative correlation of blood vs tissue myeloid-derived suppressor cells), but also generated promising new leads such as baseline levels of B cells, platelets and nuocytes in the skin prior to BCG administration predict eventual outcome, and that these predictive differences in baseline cellular composition can be captured non-invasively using high resolution images of the site of injection (dermatoscopy). Given this data represents the first holistic view of the acute molecular response to BCG in the skin in a human population at medium to high TB risk, we anticipate our findings of the immediate/early events following BCG vaccination, including non-invasive predictive assessment will support acceleration of vaccine development in the fight against TB.

systems biology↗

Leveraging death of drug-sensitive cancer cells to promote immune-mediated bystander killing of subclones of drug-resistant tumor cells

The response of lung cancer patients to drugs targeting the G12C mutant form of KRAS is limited by the development of resistance through multiple mechanisms. In order to achieve lasting benefit with these therapies, effective strategies for tackling the evolution of drug resistance are required. We have developed a preclinical model system to mimic the development of resistance to KRAS G12Ci inhibitors (G12Ci) such as adagrasib and RMC-4998. Treatment of tumours containing a minor subpopulation of resistant cancer cells with G12Ci leads to their rapid outgrowth to replace the drug-sensitive cells within a few weeks. However, when combined with therapies that, at least in part, target the immune response, such as SHP2 inhibitors or PD-1 blockade, drug-resistant cells can be eliminated, even by drug combinations that do not impact their growth in the absence of drug-sensitive cells. This bystander killing of drug-resistant cells when drug-sensitive cells are targeted is dependent on an intact adaptive immune system. Mechanistically, these combination therapies lead to profound remodelling of the tumour immune microenvironment, with influx of T cells recognising a tumour associated antigen shared between drug-resistant and drug-sensitive cancer cells. Promotion of immune-mediated bystander killing of drug-resistant cells may provide a paradigm for tackling the problem of drug resistance in cancer more broadly.

cancer biology↗

Swine reporter model for preclinical evaluation and characterization of gene delivery vectors

Delivery of gene therapy vectors targeted to any somatic cell remains a key barrier for the development of genetic medicines. While rodent models provide insights into vector biodistribution and cellular tropism, their anatomical and physiological differences from humans limit their translational potential and studies in large animal models are often required. In this study, we developed a swine reporter model (SRM-1) to evaluate both viral and nonviral vector delivery in a large animal system. The SRM-1 model harbors a Cre- and CRISPR-activated tdTomato reporter at the Rosa26 locus that allows for tracing of cell-specific delivery and expression of gene therapy vectors in vivo. To evaluate this model, we administered adeno-associated virus serotype 9 (AAV9) and lipid nanoparticles (LNPs) carrying mRNA systemically and found successful in vivo reporter activation across a variety of tissues. Intracerebroventricular (ICV) administration of LNP-Cre mRNA was also performed and demonstrated localized activation in cortical brain cells. In addition to biodistribution studies, this model has utility for testing safety and clinically relevant administration methods, surgical and non-surgical, of delivery vectors. Our findings support the SRM-1 model as a valuable tool for advancing gene therapies from preclinical testing to clinical application.

genetics↗

Distinct druggable biological processes in early-onset prostate cancer

Despite advances in understanding and treating Prostate Cancer (PCa), there has been little effort to systematically map the biology distinguishing Early-(EOPCa) and Late-(LOPCa) onset PCa. Around 25% of EOPCa cases present with metastatic spread or aggressive disease with earlier metastatic development. Some available lines of therapy are extending treatment trajectories and prolonging lives. However, there remains a critical clinical need to identify new therapeutic targets for EOPCa where life expectancy necessitates safer, more targeted treatment options. To our knowledge, here we present the largest systematic analysis of molecular profiles in EOPCa versus LOPCa, employing machine-learning-enabled algorithms to identify distinguishing biology and druggable targets for each age group. Distinct stromal signatures are uncovered in EOPCa, which are used to propose therapeutic opportunities herein. Moreover, our analysis identifies 50 druggable targets, 11 of which we confirm in PCa cell line genetic/pharmacological perturbation data. These findings provide the first specific, testable hypotheses in EOPCa, offering avenues for experimental validation and potential therapeutic exploitation, and, more generally, shed light on the intricate and distinguished molecular profile of this aggressive, poorly understood disease. One Sentence SummaryMachine learning-enabled algorithms were utilized to identify distinguishing biology and associated druggable targets for early-onset prostate cancers.

cancer biology↗

Expanding the Tubulin Code: TTLL11 Polyglutamylase Drives Elongation of Primary Tubulin Chains

Microtubules (MTs) undergo diverse post-translational modifications that regulate their structural and functional properties. Among these, polyglutamylation - a dominant and conserved modification targeting the unstructured tubulin C-terminal tails - plays a pivotal role in defining the tubulin code. Here, we uncovered a novel mechanism by which tubulin tyrosine ligase-like 11 (TTLL11) expands and diversifies the code. Cryo-electron microscopy revealed a unique bipartite MT recognition strategy wherein TTLL11s binding and catalytic domains engage adjacent MT protofilaments. Biochemical assays identified previously unknown polyglutamylation patterns, showing that TTLL11 directly extends the primary polypeptide chains of - and {beta}-tubulin, challenging the prevailing paradigms emphasizing lateral branching. Moreover, cell-based and in vivo data firmly established a crosstalk between TTLL11-mediated polyglutamylation and other tubulin-modifying processes, notably the detyrosination/tyrosination cycle. This discovery unveils an unrecognized layer of complexity within the tubulin code and offers new insights into the molecular basis of functional specialization of cytoskeleton across diverse cellular contexts.

biochemistry↗

Suprachiasmatic Neuromedin-S Neurons Regulate Arousal

Mammalian circadian rhythms, which orchestrate the daily temporal structure of biological processes, including the sleep-wake cycle, are primarily regulated by the circadian clock in the hypothalamic suprachiasmatic nucleus (SCN). The SCN clock is also implicated in providing an arousal signal, particularly during the wake-maintenance zone (WMZ) of our biological day, essential for sustaining normal levels of wakefulness in the presence of mounting sleep pressure. Here we identify a role for SCN Neuromedin-S (SCNNMS) neurons in regulating the level of arousal, especially during the WMZ. We used chemogenetic and optogenetic methods to activate SCNNMS neurons in vivo, which potently drove wakefulness. Fiber photometry confirmed the wake-active profile of SCNNM neurons. Genetically ablating SCNNMS neurons disrupted the sleep-wake cycle, reducing wakefulness during the dark period and abolished the circadian rhythm of body temperature. SCNNMS neurons target the dorsomedial hypothalamic nucleus (DMH), and photostimulation of their terminals within the DMH rapidly produces arousal from sleep. Pre-synaptic inputs to SCNNMS neurons were also identified, including regions known to influence SCN clock regulation. Unexpectedly, we discovered strong input from the preoptic area (POA), which itself receives substantial inhibitory input from the DMH, forming a possible arousal-promoting circuit (SCN->DMH->POA->SCN). Finally, we analyzed the transcriptional profile of SCNNMS neurons via single-nuclei RNA-Seq, revealing three distinct subtypes. Our findings link molecularly-defined SCN neurons to sleep-wake patterns, body temperature rhythms, and arousal control. Significance StatementOur studys findings provide a cellular and neurobiological understanding of how Neuromedin-S (NMS)-containing SCN neurons contribute to regulating circadian rhythms, sleep-wake patterns, body temperature, and arousal control in mammals. This research illuminates the circuit, cellular, and synaptic mechanisms through which SCN neurons regulate daily cycles of wakefulness and sleep, with implications for understanding and potentially manipulating these processes in health and disease.

neuroscience↗

Ankyrins are essential for synaptic integrity of photoreceptors in the mouse outer retina

Retinal circuit assembly relies on the precise timing and positioning of key molecules between neuronal partners to mediate proper synapse formation. In the outer retina, horizontal cells are important interneurons that make the first contacts to photoreceptors and begin to segregate visual information into two distinct pathways by selectively forming synapses to the different types of photoreceptors. Dendrites of horizontal cells synapse exclusively to cone photoreceptors whereas the axon terminal synapses to rod photoreceptors. Failure to properly form these early connections disrupts the downstream connectivity of other postsynaptic neurons and leads to abnormal visual function. Although these early events are critical for proper synapse development, little is known about the molecular mechanisms that establish horizontal cell to photoreceptor connectivity during development. In the present study, we performed single-cell RNA sequencing and uncovered new molecules that are highly expressed in horizontal cells. These include different members of the cytoskeletal scaffolding family of Ankyrins that are known to form specialized regions within neurons by recruiting different molecules to the membrane and linking them to the cytoskeleton. Specifically, we found Ankyrin-B to be highly expressed in horizontal cells at early time points and Ankyrin-G to be expressed at later stages. Loss of both Ankyrin-B and Ankyrin-G leads to synaptic defects between horizontal cells and photoreceptors and disrupts in vivo retinal responses. In summary, our findings uncovered a new role for Ankyrins in mediating synaptic connectivity between horizontal cells and photoreceptors required for normal visual function. SIGNIFICANCE STATEMENTIn the mammalian retina, the first synapse between photoreceptors and their downstream targets begins to separate visual information into two distinct pathways. During retinal development, photoreceptors first make contacts to horizontal cells in a temporal- and spatial-specific manner. Although this initial contact is critical for synaptogenesis, little is known about the key molecules responsible for selective wiring of horizontal cells to photoreceptors. In this study, we performed single-cell RNA sequencing and identified the family of cytoskeletal scaffolding proteins Ankyrins to be differentially expressed in horizontal cells. Loss of Ankyrins impairs synaptic connectivity between horizontal cells and their photoreceptor partners leading to abnormal visual responses. Taken together, our work uncovered a new function of Ankyrins at photoreceptor synapses.

neuroscience↗

First record of the seagrass Halophila stipulacea (Forskkal) Ascherson in the waters of the continental United States (Key Biscayne, Florida)

The first record of Halophila stipulacea is reported for the continental waters of the United States. In August 2024, a small meadow was identified inside Crandon Marina on Key Biscayne, Florida, USA. Following surveys have revealed that H. stipulacea has spread to adjacent areas immediately outside of the marina, often growing either in close proximity to, or interspersed with, the native seagrasses Thalassia testudinum, Syringodium filiforme, and Halodule wrightii. This serves as an initial report and extends the geographic scope of this introduced species in the Western Atlantic basin.

ecology↗

Temperature drives seagrass recovery across the Western North Atlantic

Climate-driven shifts in herbivores, temperature and nutrient runoff threaten coastal ecosystem resilience. However, our understanding of ecological resilience, particularly for foundation species, remains limited due to a rarity of field experiments that are conducted across appropriate spatial and temporal scales and that investigate multiple stressors. This study aimed to evaluate the resilience of a widespread tropical marine plant (turtlegrass) to disturbances across its geographic range and how this is impacted by environmental gradients in (a)biotic factors. We assessed the resilience (i.e. recovery) of turtlegrass to a simulated disturbance (complete above- and belowground biomass removal) over a year. Contrary to temperate studies, higher temperature generally enhanced seagrass recovery. While nutrients and light availability had minimal impact, combined high levels of nutrients and herbivore grazing (meso and megaherbivore) reduced aboveground recovery. Our results suggest that the resilience of some tropical species, especially in cooler subtropical waters, may initially increase with warming.

ecology↗

Ultrasound system for precise neuromodulation of human deep brain circuits

Transcranial ultrasound stimulation (TUS) has emerged as a promising technique for non-invasive neuromodulation, but current systems lack the precision to target deep brain structures effectively. Here, we introduce an advanced TUS system that achieves unprecedented precision in deep brain neuromodulation. The system features a 256-element, helmet-shaped transducer array operating at 555 kHz, coupled with a stereotactic positioning system, individualised treatment planning, and real-time monitoring using functional MRI. In a series of experiments, we demonstrate the systems ability to selectively modulate the activity of the lateral geniculate nucleus (LGN) and its functionally connected regions in the visual cortex. Participants exhibited significantly increased visual cortex activity during concurrent TUS and visual stimulation, with high reproducibility across individuals. Moreover, a theta-burst TUS protocol induced robust neuromodulatory effects, with decreased visual cortex activity observed for at least 40 minutes post-stimulation. These neuromodulatory effects were specific to the targeted LGN, as confirmed by control experiments. Our findings highlight the potential of this advanced TUS system to non-invasively modulate deep brain circuits with high precision and specificity, offering new avenues for studying brain function and developing targeted therapies for neurological and psychiatric disorders. The unprecedented spatial resolution and prolonged neuromodulatory effects demonstrate the transformative potential of this technology for both research and clinical applications, paving the way for a new era of non-invasive deep brain neuromodulation.

neuroscience↗

β-arrestin-biased Allosteric Modulator of Neurotensin Receptor 1 Reduces Ethanol Drinking and Responses to Ethanol Administration in Rodents

Alcohol use disorders (AUDs) impose an enormous societal and financial burden, and world-wide, alcohol misuse is the 7th leading cause of premature death1. Despite this, there are currently only 3 FDA approved pharmacological treatments for the treatment of AUDs in the United States. The neurotensin (Nts) system has long been implicated in modulating behaviors associated with alcohol misuse. Recently, a novel compound, SBI-553, that biases the action of Nts receptor 1 (NTSR1) activation, has shown promise in preclinical models of psychostimulant misuse. Here we investigate the efficacy of this compound to alter ethanol-mediated behaviors in a comprehensive battery of experiments assessing ethanol consumption, behavioral responses to ethanol, sensitivity to ethanol, and ethanol metabolism. Additionally, we investigated behavior in avoidance and cognitive assays to monitor potential side effects of SBI-553. We find that SBI-553 reduces binge-like ethanol consumption in mice without altering avoidance behavior or novel object recognition. We also observe sex-dependent differences in physiological responses to sequential ethanol injections in mice. In rats, we show that SBI-553 attenuates sensitivity to the interoceptive effects of ethanol (using a Pavlovian drug discrimination task). Our data suggest that targeting NTSR1 signaling may be promising to attenuate alcohol misuse, and adds to a body of literature that suggests NTSR1 may be a common downstream target involved in the psychoactive effects of multiple reinforcing substances.

neuroscience↗

A resource for development and comparison of multi-modal brain 3T MRI harmonisation approaches

Despite the huge potential of magnetic resonance imaging (MRI) in mapping and exploring the brain, MRI measures can often be limited in their consistency, reproducibility and accuracy which subsequently restricts their quantifiability. Nuisance nonbiological factors, such as hardware, software, calibration differences between scanners, and post-processing options can contribute to, or drive trends in, neuroimaging features to an extent that interferes with biological variability. Such lack of consistency, known as lack of harmonisation, across neuroimaging datasets poses a great challenge for our capabilities in quantitative MRI. Here, we build a new resource for comprehensively mapping the extent of the problem and objectively evaluating neuroimaging harmonisation approaches. We use a travelling-heads paradigm consisting of multimodal MRI data of 10 travelling subjects, each scanned at 5 different sites on 6 different 3T scanners from all the 3 major vendors and using 5 neuroimaging modalities, providing more comprehensive coverage than before. We also acquire multiple within-scanner repeats for a subset of subjects, setting baselines for multi-modal scan-rescan variability. Having extracted hundreds of image-derived features, we compare three forms of variability: (i) between-scanner, (ii) within-scanner (within-subject), and (iii) biological (between-subject). We characterise the reliability of features across scanners and use our resource as a testbed to enable new investigations that until now have been relatively unexplored. Specifically, we identify optimal pipeline processing steps that minimise between-scanner variability in extracted features (implicit harmonisation). We also test the performance of post-processing harmonisation tools (explicit harmonisation) and specifically check their efficiency in reducing between-scanner variability against baseline standards provided by our data. Our explorations allow us to come up with good practice suggestions on processing steps and sets of features where results are more consistent, while our publicly-released datasets establish references for future studies in this field.

neuroscience↗