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Ferguson, A. R.

Publications and source records attributed to Ferguson, A. R..

At least 19 recordsLinked to original sources

Polytraumatic SCI worsens maladaptive plasticity in spinal motor systems

Spinal cord injury (SCI) results in dysfunction of both motor and sensory systems, which can be characterized by neuropathic pain, hypersensitivity, muscular spasticity and rigidity. Most SCIs result from incidents such as vehicle accidents or falls, resulting in polytraumatic SCI that includes peripheral injuries in addition to direct CNS damage. Recent findings suggest that spinal cord synaptic plasticity plays a crucial role in neuropathic pain pathophysiology, specifically in association with spinal sensitization and the consequent onset of AMPA-related maladaptive plasticity. Further findings have demonstrated that nociceptive peripheral stimulation in the acute phase of SCI results in maladaptive spinal synaptic plasticity by overdriving GluA2-lacking calcium-permeable AMPARs (CP-AMPARs). Here, we investigated the effect of a spared nerve injury (SNI) in conjunction with SCI to determine the effect of polytraumatic SCI on maladaptive plasticity in the spinal cord. Near-IR quantitative Western blot analysis demonstrated that SCI+SNI increases spinal GluA1 expression, but not GluA2. Patch-clamp confirmed that AMPAR currents in spinal motorneurons increase after SCI with SNI, and decrease after the administration of NASPM, a CP-AMPAR antagonist. Data-driven analysis using non-linear principal components analysis (NL-PCA) also demonstrated that SCI with SNI produces a multivariate signature of AMPAR plasticity that is observed in other forms of nociceptive peripheral input, indicating a general mechanism for maladaptive plasticity in spinal motor systems in response to polytraumatic SCI.

neuroscience↗

Protein Predictors of Worsening Cerebral Edema in Traumatic Brain Injury in Critically Ill Patients

Cerebral edema (CE) is a major determinant of poor outcomes after traumatic brain injury (TBI). CE affects approximately 60% of patients with mass lesions on head computed tomography (hCT) and confers a tenfold increase in mortality. Despite this burden, no validated biomarkers exist to identify patients at risk for early CE worsening or to elucidate the biological processes underlying divergent edema trajectories. We conducted high-throughput plasma proteomic profiling in a prospective moderate-severe TBI cohort with evidence of intracranial blood on the initial post-injury hCT scan (n=123 patients) to (1) identify a clinically feasible set of biomarkers plus a predictive model that could be used to assess CE risk at admission, and (2) conduct a mechanistic, hypothesis-generating analysis to identify the molecular networks involved in CE progression in the first hours post-injury. Plasma collected within 3 hours of injury was analyzed using the Olink Explore platform (5394 proteins), and patients underwent head CT imaging upon presentation and at 6 hours. Two complementary analytic pathways, reflecting the studys two goals, were pursued in parallel. First, logistic regression with false discovery rate (FDR) correction identified a conservative 12-protein set associated with baseline CE. When combined with targeted clinical variables (i.e., age, sex, admission GCS, pupil reactivity, admission glucose, admission alcohol), this panel supported high-performing supervised classifiers for predicting CE worsening by 6 hours post-baseline scan (best model: XGBoost, AUC = 0.78; recall = 0.83). Second, a broader 60-protein panel, selected via bootstrapped elastic-net regression, was used to interrogate the mechanistic architecture of CE worsening using random forest SHAP attribution and protein-protein interaction modeling. Proteomic signatures diverged sharply between patients whose CE did and did not worsen. The CE worsening group was characterized by a coherent neuronal-synaptic injury axis dominated by ELAVL4, CEND1, NEFL, NECAB2, GFAP, CHGB, RPH3A, HPCAL4, and HOMER1, proteins involved in neuronal structural integrity, vesicular trafficking, synaptic vesicle cycling, calcium signaling, and axonal degeneration. These reciprocal proteomic states suggest that early edema progression may be driven by coordinated disruption of neuronal and synaptic resilience programs. Together, these findings suggest (1) a hyperacute biomarker panel plus predictive model with potential for prospective validation and (2) mechanistic evidence for a distinct neuronal-synaptic injury network that associates with early edema worsening after TBI.

neuroscience↗

Aerobic exercise prevents the loss of endogenous pain modulation in male and female rats with traumatic brain injury.

Traumatic Brain Injury (TBI) patients may suffer from a number of long-term complications after injury such as impaired motor skills, cognitive decline, and sensory abnormalities including chronic pain. Disruption of endogenous pain modulatory pathways likely contributes to development of chronic pain in a wide range of conditions including TBI. Aerobic exercise has been shown to impact pain syndromes. Here we investigate the effect of exercise on pain outcome measures after TBI using a lateral fluid percussion (LFP) model and voluntary running wheels in male and female rats. We tested mechanical nociceptive reactivity with von Frey fibers and descending control of nociception (DCN) using hindpaw sensitization with PGE2 followed by a capsaicin-test stimulus to the forepaw. Pharmacological studies employed the administration of noradrenergic (NA) and serotoninergic receptor blockers. Neuropathological studies quantified neuroinflammatory changes and axonal damage. We found that exercise decreased the duration of the acute phase of pain from [~]5 weeks to 2-3 weeks in female and male TBI rats respectively, gains that could be reversed using the 1-adrenoceptor (1AR) antagonist, prazosin. Exercise also prevented the loss of DCN for at least 180 days post-injury in both male and female TBI rats. The intact DCN response in male and female TBI rats provided by exercise could be blocked using prazosin. Surprisingly, exercise-mediated restoration of the DCN response in male TBI rats was not blocked by the 5-HT7 receptor antagonist, SB-267790, the receptor system through which serotonin reuptake inhibitors restore DCN after TBI in male rats. Therefore, the transition from a noradrenergic to a serotonergic inhibitory pain pathway that we typically see in male TBI rats, was blocked by exercise. Assessment of neuropathology, acutely after TBI, reveals that both the astrocyte and microglial response to injury is significantly greater in male TBI compared to female TBI, regardless of exercise. The effect of exercise on the extent of neuroinflammation after injury was minimal in TBI rats of both sexes. In contrast, exercise significantly decreased the amount of axonal loss in the corpus callosum in both male and female TBI rats compared to sedentary TBI rats. However, the extent of axonal loss after TBI in both exercise and sedentary male rats was greater than in female exercise and sedentary groups respectively. These results demonstrate that exercise is a promising treatment for chronic pain after TBI in both male and females. It also highlights that dysfunction of the endogenous pain modulatory pathways observed in male rats after TBI can be prevented by exercise, possibly by reducing axonal loss.

neuroscience↗

PRECISE TBI Model Catalog: Increasing Accessibility and Reproducibility in TBI research

Preclinical traumatic brain injury (TBI) research relies on experimental models that vary by mechanism, parameters, surgical procedures, species, strains, and ages, to name a few. While these models are crucial for understanding injury mechanisms and testing therapies, the progress in translating this knowledge to the clinic has been limited. This is in part due to fragmented resources and inconsistent reporting of critical variables. Here, we introduce the PRECISE-TBI model catalog, a centralized, queryable resource that consolidates metadata from published studies. The catalog integrates curated annotations from more than 450 papers, including details such as age, sex, strain, model type, device, and injury parameters. Where available, entries are also linked to protocols and datasets to enhance transparency and reproducibility. The Model Catalog serves as a living resource that enables cross-study comparison, identifies gaps in reporting, and connects the literature to datasets, protocols, device information, and other relevant resources. Analysis of the initial catalog entries revealed gaps in the reporting of device, age, and weight. In contrast, the reporting of sex improved over time, with over 90% of recent studies within the catalog papers reporting sex. Strain was also reported in most studies, with consistent reporting of specificity, especially for the C57 mice substrain. We expect the Model Catalog to serve as a valuable tool to enhance study design and reproducibility in preclinical TBI research while advancing FAIR data principles in the TBI field.

neuroscience↗

Rigor and Transparency in two neurotrauma-publishing journals: editorial policies improve transparent reporting.

Preclinical research in traumatic brain injury (TBI) continues to significantly increase knowledge and yield a large number of peer-reviewed studies, but translation of these results to the clinical setting has been minimal. Rigor and transparency factors such as concealment of group allocation (e.g., "blinding) or ensuring that reagents are identifiable are critical in ensuring that scientific studies are replicable and translatable. Yet, nearly all efforts aimed at measuring these factors have concluded that reporting practices are problematic and incomplete. One way to improve transparency of reporting practices is to require that authors address a set of transparency related items in some way, such as a checklist or a paper section. Recently, Journal of Neurotrauma, a leading publisher of preclinical TBI research, instituted a required rigor-related section, which is explained to authors via a set of transparency, rigor, and reproducibility (TRR) instructions (one example for each manuscript type). These documents include specific transparency sections explaining blinding, power calculations, protocols, code, and data deposition. Experimental Neurology is a journal that is similar in size, impact and topic but the journal does not have explicit instructions to authors about transparency items. The purpose of this study was to assess the degree to which transparency reporting items were included in published manuscripts comparing reporting practices in the Journal of Neurotrauma and Experimental Neurology. We used a commercial software, SciScore, which is an AI tool tuned to detect rigor/transparency sentences in published manuscripts and count the number found (roughly dividing by the number expected) to obtain a score. Overall, SciScore found that in 6 of 8 items that were explicitly asked for, such as power calculations, investigator blinding, inclusion criteria, attrition, and data were significantly greater (more than 10%) compared to Experimental Neurology. However in Journal of Neurotrauma papers with the extra rigor section, 3 of 4 rigor items that were not explicitly asked for in the template rigor documents, such as subject demographics or transparent antibody reporting were not different from Experimental Neurology. One item, reporting of the sex of subjects was significantly better in Experimental Neurology. This shows that the Journal of Neurotrauma required rigor section is effective in improving reporting, but it would be far better if sex as a biological variable and transparent reporting of reagents (items present on major checklists including NIH rigor criteria) would be included.

scientific communication and education↗

A proteomic signature of vascular dysfunction linked to tauopathy and degeneration in the aging brain

Small vessel disease (SVD) impacts healthy aging of organs across the body, yet its contributions to adverse brain aging remain poorly defined. Here we show thromboinflammation, a core feature of SVD, as a driver of adverse brain aging. We identify cerebrospinal fluid fibrinogen as a marker of brain thromboinflammation and screen neurovascular biosignatures mediating its impact on synaptic vulnerability along the full spectrum of brain aging from cognitively typical, amyloid-negative to cognitively impaired, amyloid-positive older adults. We identified 53 proteins mediating fibrinogens effects on synaptic markers in 1,655 donors from three independent cohorts. Single-cell transcriptomic mapping revealed mediator enrichment in neurovascular unit cells. Pathway analysis demonstrated dysregulation of angiogenesis, fibrosis, and immune signaling. Vascular and microglial-enriched biosignatures associated with compromised white matter integrity. These findings indicate thromboinflammation as an early, amyloid-independent pathway to neurodegeneration and tauopathy, establishing vascular health as fundamental to preserving brain healthspan.

neuroscience↗

Increased Synapse Elimination by Inflammatory Cells Contributes to Long-lasting Post-Stroke Memory Dysfunction in Old Mice

Old patients are more likely to experience memory dysfunction than young patients after a stroke. It has been reported that brain astrocytes and microglia cause excessive removal of synapses at the acute and subacute stages of stroke, and inhibition of their phagocytosis improved neurobehavioral outcomes. We hypothesized that memory dysfunction in old subjects is associated with increased synapse removal by inflammatory cells. Ischemic stroke was induced in young (2-month-old) and old (15-18-month-old) mice. Memory functions were analyzed by the Y-maze test weekly for 8 weeks and the novel object recognition (NOR) test at 7 days before and 8 weeks post-stroke. We have also created a tibia fracture 6 hours before stroke injury in young mice, to test if the activation of 7-nicotinic acetylcholine receptor (nAchRs) reduces inflammatory cells and synapse elimination. Brains were collected 8 weeks after the induction of ischemic stroke. Transcriptome changes, neuronal injuries, neuroinflammation, synapse removal, and neurite outgrowth were analyzed. We found that old mice developed long-term memory dysfunction after ischemic stroke, which was not seen in young mice. Old mice showed larger infarct volume, higher neuroinflammation, and more synapses engulfed by microglia/macrophages and astrocytes in the peri-atrophic region and hippocampi than young mice. More synapse-engulfing astrocytes than microglia/macrophages were present in the peri-atrophic region and the ipsilateral hippocampi, suggesting that reactive astrocytes contributed more than activated microglia/macrophages in synapse removal. Activation of 7-nAchRs in mice subjected to tibia fracture 6 hours before ischemic injury reduced synapse removal by microglia/macrophages and astrocytes in the hippocampi. Our study indicated that an increase in synaptic elements by inflammatory cells contributes to the long-lasting memory deficit after stroke in old mice. Astrocytes may contribute more than microglia/macrophages in synapse removal. Inhibition of neuroinflammation by activating 7-nAchRs can reduce synapse loss and thus may improve post-stroke memory function.

neuroscience↗

Improved Injury Detection Through Harmonizing Multi-Site Neuroimaging Data after Experimental TBI: A Translational Outcomes Project in NeuroTrauma (TOP-NT) Consortium Study

Multi-site neuroimaging studies have become increasingly common in order to generate larger samples of reproducible data to answer questions associated with smaller effect sizes. The data harmonization model NeuroCombat has been shown to remove site effects introduced by differences in site-related technical variance while maintaining group differences, yet its effect on improving statistical power in pre-clinical models of CNS disease is unclear. The present study examined fractional anisotropy data computed from diffusion weighted imaging data at 3 and 30 days post-controlled cortical impact injury from 184 adult rats across four sites as part of the Translational-Outcome-Project-in-Neurotrauma (TOP-NT) Consortium. Findings confirmed prior clinical reports that NeuroCombat fails to remove site effects in data containing a high proportion-of-outliers (>5%) and skewness, which introduced significant variation in non-outlier sites. After removal of one outlier site and harmonization using a global sham population, harmonization displayed an increase in effect size in data that displayed group level effects (p<0.01) in both univariate and voxel-level volumes of pathology. This was characterized by movement toward similar distributions in voxel measurements (Kolmogorov-Smirnov p<<0.001 to >0.01) and statistical power increases within the ipsilateral cortex. Harmonization improved statistical power and frequency of significant differences in areas with existing group differences, thus improving the ability to detect regions affected by injury rather than by other confounds. These findings indicate the utility of NeuroCombat in reproducible data collection, where biological differences can be accurately revealed to allow for greater reliability in multi-site neuroimaging studies. Significance StatementThis project demonstrates the utility of NeuroCombat in reducing site effects in multi-site rodent imaging. We also demonstrate that harmonization improves the ability to distinguish between sham and injured rats at the voxel level and increase statistical power and effect size in areas of injury. Multi-center studies are becoming more common to allow for increased efficiency in data collection, and with conservative approaches and analysis into the datasets, NeuroCombat can be utilized to improve study reliability and reproducibility.

neuroscience↗

Conditioning electrical stimulation enhances functional rewiring in a mouse model of nerve transfer to treat chronic spinal cord injury

Nerve transfer surgery is a state-of-the-art surgical approach to restore hand and arm function in individuals living with tetraplegia, significantly impacting daily life. While nearly a third of all individuals with chronic SCI may benefit from this intervention, variability in outcomes can limit the functional impact. A bedside-to-bench approach was taken to address the variable response of tetraplegic individuals to nerve transfer surgery. We used a hierarchical multiple factor analysis to evaluate the effects of conditioning electrical stimulation (CES) on outcomes in a mouse model of nerve transfer to treat chronic cervical spinal cord injury. We found that CES of donor nerves one week prior to nerve transfer surgery enhanced anatomical and functional measures of innervation of targeted muscles. Furthermore, CES increased the rate of recovery of naturalistic behavior. While the model has some limitations due to the small size of the rodent, our results support the use of CES as an effective approach to improve outcomes in clinical nerve repair settings.

neuroscience↗

A novel HLA Class II presentation prediction algorithm deciphers immunogenic CD4 epitopes specific to KRAS G12C

Accurate prediction of peptide presentation by HLA molecules is important for generation of effective individualized cancer vaccines and immunotherapies. While presentation prediction algorithms for HLA class I have been successfully applied in the context of such therapies, improved prediction algorithms for class II are needed. EDGE-II is a novel algorithm based on a protein large language model that has a learned allele deconvolution network trained on existing and new immunopeptidomics data. It delivers state-of-the-art performance on prediction of peptide presentation by HLA class II and immunogenicity elicited by CD4+ T-cell epitopes. In a patient with a KRAS G12C positive tumor treated with a KRAS G12C targeting immunotherapy, EDGE-II identified KRAS G12C class II neoantigens that elicited clonally expanded CD4+ T cells with cytotoxic transcriptional profiles post-vaccination. EDGE-II could play an important role in the development of effective cancer immunotherapies by elucidating an enriched understanding of the immunopeptidome.

bioinformatics↗

Comprehensive Longitudinal ctDNA Monitoring in Metastatic Cancer Patients Treated with an Individualized Neoantigen-directed Vaccine

PurposeCirculating-tumor DNA (ctDNA) is an emerging, minimally invasive diagnostic and prognostic biomarker for patients receiving a variety of cancer therapies. Comprehensive and robust longitudinal monitoring of ctDNA can provide an understanding of tumor burden, heterogeneity, and response or resistance to treatment. Experimental DesignctDNA of 28 metastatic cancer patients receiving an individualized neoantigen-directed immunotherapy was monitored longitudinally, up to two years, using a unique hybrid next generation sequencing assay targeting tumor-informed and tumor-naive variants. Patient-specific panels were designed targeting an average of 144 variants per patient. A tumor-naive universal panel was also designed for inclusion with patient-specific panels to monitor recurrently mutated tumor hotspots (e.g., KRAS and TP53) and genes implicated in immunotherapy resistance (B2M, TAP1/2). ResultsAnalytical characterization of the assay established linearity with a mean variant allele frequency (VAF) [&ge;]0.049%, and a variant-level limit of detection (LOD95) of 0.12%. Tumor-informed variants were detected in 26/28 patients, and de novo variants were observed in 25/28 patients. HLA LOH was also observed. Longitudinal ctDNA data provided key insights into patients responses to vaccine treatment. ConclusionsThe hybrid design of the ctDNA monitoring assay provides the sensitivity and specificity required for evaluating patient samples undergoing individualized therapy. It provides an improved capability to understand patient response to experimental therapies and further supports the utility of ctDNA as a cancer biomarker.

genomics↗

Plasma Proteomics of Genetic Brain Arteriosclerosis and Dementia Syndrome Identifies Signatures of Fibrosis, Angiogenesis, and Metabolic Alterations

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the most common monogenic form of vascular cognitive impairment and dementia. A genetic arteriolosclerotic disease, the molecular mechanisms driving vascular brain degeneration and decline remain unclear. With the goal of driving discovery of disease-relevant biological perturbations in CADASIL, we used machine learning approaches to extract proteomic disease signatures from large-scale proteomics generated from plasma collected from three distinct cohorts in US and Colombia: CADASIL-Early (N = 53), CADASIL-Late (N = 45), and CADASIL-Colombia (N = 71). We extracted molecular signatures with high predictive value for early and late-stage CADASIL and performed robust cross- and external-validation. We examined the biological and clinical relevance of our findings through pathway enrichment analysis and testing of associations with clinical outcomes. Our study represents a model for unbiased discovery of molecular signatures and disease biomarkers, combining non-invasive plasma proteomics with clinical data. We report on novel disease-associated molecular signatures for CADASIL, derived from the accessible plasma proteome, with relevance to vascular cognitive impairment and dementia.

neuroscience↗

Using behavioral biomarkers to redefine epochs of spontaneous recovery following spinal cord injury

The brain-spinal cord axis generates movement by assembling motor primitives into coordinated sequences. Spinal cord injury (SCI) disrupts this neuroaxis, impairing not only locomotion, but the full repertoire of behavior. Traditional scales for quantifying recovery collapse this complexity into predefined locomotor-focused criteria that obscure heterogeneity in recovery. To quantify the full behavioral repertoire following SCI, we adapted motion sequencing (MoSeq) to identify sub-second behavioral "syllables" and capture their usage and sequential organization without predefined features. We identified biomechanically distinct variants within syllable classes that are shared across injury severities and found that recovery is jointly structured by injury severity and individual mouse identity. Changes in sequences, however, unfold along a conserved temporal trajectory. By compressing behavior into a single metric, we uncovered clusters of coevolving locomotor and non-locomotor behaviors. These results frame SCI recovery with repertoire-level changes, where adaptive strategies emerge from constrained access to motor primitives and their sequences.

neuroscience↗

Brain Injury Knowledge Ontology (BIKO) for traumatic brain injury: Formalizing concepts and methods used in translational traumatic brain injury research.

Traumatic brain injury (TBI) is an insult to the brain resulting from an external force and is a significant cause of morbidity and mortality in the United States. No effective clinical therapeutics currently exist for this injury. Although several therapies and procedures have been deemed successful for TBI treatment in preclinical research studies, they have yet to be translated into human patients. These discouraging results have left many scientists questioning the role of animal models in drug discovery for TBI. One major hurdle in translating the knowledge obtained in the laboratory to the clinic is the methodological variance across these studies. This variance can hinder the ability to draw conclusions from conflicting studies and aggregate data across various research studies, which ultimately impedes the ability to aggregate data across these studies. Therefore, addressing this variance is crucial for bridging the gap between the laboratory and the clinic. The increasing volume of papers and associated data being published every day makes this hurdle even more difficult to overcome. The initial steps to address these knowledge gaps are identifying these studies and creating a shared knowledge framework for mapping their terminology. We are developing the Brain Injury Knowledge Ontology (BIKO) to create a standardized model to describe methods and outcome measures used within preclinical and clinical TBI therapy studies to facilitate comparison across studies and models. The first version of BIKO focuses on modeling the major preclinical TBI models, e.g., Controlled Cortical Impact Model, Fluid Percussion Model, and Weight-Drop Model), major neurological injuries related to these models and their relationship to clinical pathophysiology. We show how BIKO provides a machine-readable way to represent the methodologies used in TBI therapeutic studies to compare models across clinically relevant features.

bioinformatics↗

Enlarged Perivascular Spaces are Associated with White Matter Injury, Brain Atrophy, Cognitive Decline and Markers of Inflammation in an Autosomal Dominant Vascular Neurodegenerative Disease (CADASIL)

Background and ObjectivesEnlarged perivascular spaces (ePVS) have been previously reported in Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leucoencephalopathy (CADASIL), but their significance and pathophysiology remains unclear. We investigated associations of ePVS with classical imaging measures, cognitive measures and plasma proteins to better understand what ePVS represents in CADASIL and whether radiographic measures of ePVS would be of value in future therapeutic discovery studies for CADASIL. Methods24 individuals with CADASIL and 24 age and sex matched controls were included. Disease status was determined based on presence of NOTCH3 mutation. Brain imaging measures of white matter hyperintensity (WMH), brain parenchymal fraction (BPF), ePVS volumes, clinical, and cognitive measures, as well as plasma proteomics were used in models. Global ePVS volumes were calculated via a novel, semi-automated pipeline and levels of 7363 proteins were quantified in plasma using the SomaScan assay. The relationship of ePVS with global burden of WMH, brain atrophy, functional status, neurocognitive measures, and plasma proteins were modelled with linear regression models. ResultsCADASIL and control groups did not exhibit differences in mean ePVS volumes. However, increased ePVS volumes in CADASIL were associated with increased WMH volume ({beta}=0.57, p=0.05), Clinical Dementia Rating (CDR) Sum-of-Boxes score ({beta}=0.49, p=0.04), and decreased brain parenchymal fraction (BPF) ({beta}=-0.03, p=0.10). In interaction term models, the interaction term between CADASIL disease status and ePVS volume was associated with increased WMH volume ({beta}=0.57, p=0.02), Clinical Dementia Rating (CDR) Sum-of-Boxes score ({beta}=0.52, p=0.02), decreased BPF ({beta}=-0.03, p=0.07) and Mini Mental State Examination (MMSE) score ({beta}=-1.49, p=0.03). Proteins positively associated with ePVS volumes were found to be related to leukocyte migration and inflammation, while negatively associated proteins were related to lipid metabolism. Two central hub proteins were identified in protein networks associated with ePVS volumes: CXCL8/IL-8, and CCL2/MCP-1. The levels of CXCL8/IL8 were also associated with increased WMH volume ({beta}=2.44, p < 0.01), and levels of CCL2/MCP-1 were further associated with decreased BPF ({beta}=-0.0007, p < 0.01), MMSE score ({beta}=-0.02, p < 0.01), and increased Trail Making Test B (TRAILB) completion time ({beta}=0.76, p < 0.01). No protein was associated with all 3 studied imaging measures of pathology (BPF,ePVS,WMH). DiscussionBased on associations uncovered between ePVS volumes and cognitive functions, imaging and plasma proteins, we conclude that ePVS volumes capture pathologies contributing to chronic brain dysfunction and degeneration in CADASIL, with relevance to future clinical trials for novel therapeutic discoveries to prevent decline and injury in individuals carrying NOTCH3 mutations.

neuroscience↗

Improving rigor and reproducibility in western blot experiments with the blotRig analysis software

Western blot is a popular biomolecular analysis method for measuring the relative quantities of independent proteins in complex biological samples. However, variability in quantitative western blot data analysis poses a challenge in designing reproducible experiments. The lack of rigorous quantitative approaches in current western blot statistical methodology may result in irreproducible inferences. Here we describe best practices for the design and analysis of western blot experiments, with examples and demonstrations of how different analytical approaches can lead to widely varying outcomes. To facilitate best practices, we have developed the blotRig tool for designing and analyzing western blot experiments to improve their rigor and reproducibility. The blotRig application includes functions for counterbalancing experimental design by lane position, batch management across gels, and analytics with covariates and random effects.

neuroscience↗

Sexually dimorphic differences in angiogenesis markers predict brain aging trajectories

Aberrant angiogenesis could contribute to cognitive impairment, representing a therapeutic target for preventing dementia. However, most angiogenesis studies focus on model organisms. To test the relevance of angiogenesis to human cognitive aging, we evaluated associations of circulating blood markers of angiogenesis with brain aging trajectories in two deeply phenotyped human cohorts (n=435, age 74+9) with longitudinal cognitive assessments, biospecimens, structural brain imaging, and clinical data. Machine learning and traditional statistics revealed sex dimorphic associations of plasma angiogenic growth factors with brain aging outcomes. Specifically, angiogenesis is associated with higher executive function and less brain atrophy in younger women (not men), a directionality of association that reverses around age 75. Higher levels of basic fibroblast growth factor, known for pleiotropic effects on multiple cell types, predicted favorable cognitive trajectories. This work demonstrates the relevance of angiogenesis to brain aging with important therapeutic implications for vascular cognitive impairment and dementia.

neuroscience↗

Expert-integrated automated machine learning uncovers hemodynamic predictors in spinal cord injury

Automated machine learning (AutoML) is positioned to democratize artificial intelligence (AI) by reducing the amount of human input and ML expertise needed to create prediction models. However, successful translation of ML in biomedicine requires moving beyond optimizing only for prediction accuracy and towards discovering reproducible clinical and biological inferences. Here, we present a model-agnostic framework to reinforce AutoML using strategies and tools of explainable and reproducible AI, including novel metrics for performance precision and feature instability. The framework enables clinicians to interpret AutoML-generated models for clinical and biological verifiability and consequently integrate domain expertise during model development. We applied the framework towards spinal cord injury prognostication and identified a detrimental relationship between intraoperative hypertension and patient outcome. Furthermore, our analysis captured evolving clinical practices such as faster time-to-surgery and blood pressure management that affected clinical model validation. Altogether, we illustrate how augmenting AutoML for inferential reproducibility empowers biomedical discovery and builds trust in AI processes towards effective clinical integration.

bioinformatics↗