There are no disease-modifying treatments available for geographic atrophy (GA), the advanced form of dry age-related macular degeneration. Current murine models fail to fully recapitulate the features of GA and thus hinder drug discovery. Here we describe a novel mouse model of retinal degeneration with hallmark features of GA. We used an 810 nm laser to create a retinal lesion with central sparing (RLCS), simulating parafoveal atrophy observed in patients with progressive GA. Laser-induced RLCS resulted in progressive GA-like pathology with the development of a confluent atrophic lesion. We demonstrate significant changes to the retinal structure and thickness in the central unaffected retina over a 24-week post-laser period, confirmed by longitudinal optical coherence tomography scans. We further show characteristic features of progressive GA, including a gradual reduction in the thickness of the central, unaffected retina and of total retinal thickness. Histological changes observed in the RLCS correspond to GA pathology, which includes the collapse of the outer nuclear layer, increased numbers of GFAP + , CD11b + and FcγRI + cells, and damage to cone and rod photoreceptors. We demonstrate a laser-induced mouse model of parafoveal GA progression, starting at 2 weeks post-laser and reaching confluence at 24 weeks post-laser. This 24-week time-frame in which GA pathology develops, provides an extended window of opportunity for proof-of-concept evaluation of drugs targeting GA. This time period is an added advantage compared to several existing models of geographic atrophy.

Tauopathies including Alzheimer's disease, are characterized by progressive cognitive decline, neurodegeneration and intraneuronal aggregates comprised largely of the axonal protein Tau. It has been unclear whether cognitive deficits are consequent of aggregate accumulation which compromise neuronal health and eventually lead to neurodegeneration. We use the Drosophila Tauopathy model and mixed sex populations to reveal an adult onset pan-neuronal Tau accumulation-dependent decline in learning efficacy and a specific defect in Protein Synthesis Dependent Memory (PSD-M), but not in its Protein Synthesis Independent variant. We demonstrate that these neuroplasticity defects are reversible upon suppression of new transgenic human Tau expression, but surprisingly correlate with an increase in Tau aggregates. Inhibition of aggregate formation via acute oral administration of Methylene Blue results in re-emergence of deficient memory in animals with suppressed hTau expression. Significantly, aggregate inhibition results in PSD-M deficits in hTau-expressing animals, which present elevated aggregates and normal memory if untreated with Methylene Blue. Moreover, Methylene Blue-dependent hTau aggregate suppression within adult mushroom body neurons, also resulted in emergence of memory deficits. Therefore, deficient PSD-M upon human Tau expression in the Drosophila CNS is not consequent of toxicity and neuronal loss because it is reversible. Furthermore, PSD-M deficits do not result from aggregate accumulation, which appears permissive, if not protective of processes underlying this memory variant.Intraneuronal Tau aggregate accumulation has been proposed to underlie the cognitive decline and eventual neurotoxicity that characterizes the neurodegenerative dementias known as Tauopathies. However, we show in three experimental settings that Tau aggregates in the Drosophila CNS do not impair, but rather appear to facilitate processes underlying Protein Synthesis Dependent memory within affected neurons.

We present a topological method for the detection and quantification of bone microstructure from non-linear microscopy images. Specifically, we analyse second harmonic generation (SHG) and two photon excited autofluorescence (TPaF) images of bone tissue which capture the distribution of matrix (fibrillar collagen) structure and autofluorescent molecules, respectively. Using persistent homology statistics with a signed Euclidean distance transform filtration on binary patches of images, we are able to quantify the number, size, distribution, and crowding of holes within and across samples imaged at the microscale. We apply our methodology to a previously characterized murine model of skeletal pathology whereby vascular endothelial growth factor expression was deleted in osteocalcin-expressing cells (OcnVEGFKO) presenting increased cortical porosity, compared to wild type (WT) littermate controls. We show significant differences in topological statistics between the OcnVEGFKO and WT groups and, when classifying the males, or females respectively, into OcnVEGFKO or WT groups, we obtain high prediction accuracies of 98.7% (74.2%) and 77.8% (65.8%) respectively for SHG (TPaF) images. The persistence statistics that we use are fully interpretable, can highlight regions of abnormality within an image and identify features at different spatial scales.

Cerebral microbleeds (CMBs) influence long-term prognoses of stroke patients. Streptococcus mutans expressing the collagen-binding protein Cnm induces cerebrovascular inflammation, impairing blood brain barrier integrity and causing cerebral bleeding. Here, we examine the association of Cnm-positive S. mutans with CMBs.

Interstitial fluid (ISF) from brain drains along the basement membranes of capillaries and arteries as Intramural Periarterial Drainage (IPAD); failure of IPAD results in cerebral amyloid angiopathy (CAA). In this study, we test the hypothesis that IPAD fails after subarachnoid haemorrhage (SAH). The rat SAH model was established using endovascular perforation method. Fluorescence dyes with various molecular weights were injected into cisterna magna of rats, and the pattern of IPAD after SAH was detected using immunofluorescence staining, two-photon fluorescent microscope, transmission electron microscope and magnetic resonance imaging tracking techniques. Our results showed that fluorescence dyes entered the brain along a periarterial compartment and were cleared from brain along the basement membranes of the capillaries, with different patterns based on individual molecular weights. After SAH, there was significant impairment in the IPAD system: marked expansion of perivascular spaces, and ISF clearance rate was significantly decreased, associated with the apoptosis of endothelial cells, activation of astrocytes, over-expression of matrix metalloproteinase 9 and loss of collagen type IV. In conclusion, experimental SAH leads to a failure of IPAD, clinically significant for long term complications such as CAA, following SAH.

Matrix metalloproteinase-9 (MMP9) and total amyloid-beta (Aβ) are prospective biomarkers of ocular ageing and retinopathy. These were quantified by ELISA in the vitreous and blood from controls ( = 55) and in a subset of age-related macular degeneration (AMD) patients ( = 12) for insights and possible additional links between the ocular and systemic compartments. Vitreous MMP9 levels in control and AMD groups were 932.5 ± 240.9 pg/mL and 813.7 ± 157.6 pg/mL, whilst serum levels were 2228 ± 193 pg/mL and 2386.8 ± 449.4 pg/mL, respectively. Vitreous Aβ in control and AMD groups were 1173.5 ± 117.1 pg/mL and 1275.6 ± 332.9 pg/mL, whilst plasma Aβ were 574.3 ± 104.8 pg/mL and 542.2 ± 139.9 pg/mL, respectively. MMP9 and Aβ showed variable levels across the lifecourse, indicating no correlation to each other or with age nor AMD status, though the smaller AMD cohort was a limiting factor. Aβ and MMP9 levels in the vitreous and blood were unrelated to mean arterial pressure. Smoking, another modifiable risk, showed no association with vitreous Aβ. However, smoking may be linked with vitreous ( = 0.004) and serum ( = 0.005) MMP9 levels in control and AMD groups, though this did not reach our elevated ( = 0.001) significance. A bioinformatics analysis revealed promising MMP9 and APP/Aβ partners for further scrutiny, many of which are already linked with retinopathy.

Dementia with Lewy bodies (DLB) is the second most common neurodegenerative cause of dementia, behind Alzheimer's disease (AD). The profile of inflammation in AD has been extensively researched in recent years, with evidence that chronic peripheral inflammation in midlife increases the risk of late-onset AD, and data supporting inflammation being associated with disease progression. In contrast, our understanding of the role of inflammation in DLB is less developed. Most research to date has examined inflammation in related disorders, such as Parkinson's disease, but there is now a growing range of literature examining inflammation in DLB itself. We present a review of the literature in this field, exploring a range of research methodologies including those quantifying markers of inflammation in cerebrospinal fluid, peripheral blood, post-mortem brain tissue, and using neuroimaging and preclinical data. Our review reveals evidence from PET imaging and peripheral blood analysis to support an increase in cerebral and peripheral inflammation in mild or prodromal DLB, that dissipates with disease progression. We present evidence from post-mortem brain tissue and pre-clinical studies that indicate α-synuclein directly promotes inflammation, but that also support the presence of AD co-pathology as an important factor in the profile of neuroinflammation in DLB. We propose that specific markers of inflammation may play a sentinel role in the mild stage of the disease, particularly when combined with AD pathology. We advocate further examination of the profile of inflammation in DLB through robust longitudinal studies, to enhance our understanding of the pathogenesis of the disease. The goal should be to utilise future results to develop a composite biomarker to aid diagnosis of DLB, and to potentially identify novel therapeutic targets.

Production of insect-pollinated crops is often reliant on honey bee (Apis mellifera) pollination services. Colonies can be managed and moved to meet the demands of modern intensified monoculture farming systems. Increased colony mortalities have been observed, which are thought be caused by interacting factors including exposure to pesticides, parasites, viruses, agricultural intensification, and changes in global and regional climate. However, whilst common tropospheric air pollutants (e.g. NO, particulate matter etc) are known to cause a range of negative effects on human health, there is little evidence of their impact on the health of A. mellifera. This study investigates the effects of exposure to diesel exhaust on A. mellifera, both at the level of individual foragers and on the whole colony. We exposed a series of colonies to diesel exhaust fumes for 2 h a day over the course of three weeks and contrasted their performance to a series of paired control colonies located at the same field site. We investigated markers of neuronal health in the brains of individual foragers and measured the prevalence of common viruses. Electronic counters monitored daily colony activity patterns and pollen samples from returning foragers were analysed to investigate plant species richness and diversity. The amounts of honey, brood and pollen in each colony were measured regularly. We demonstrated an upregulation of the synapse protein Neurexin 1 in forager brains repeatedly exposed to diesel exhaust. Furthermore, we found that colonies exposed to diesel exhaust lost colony weight after the exposure period until the end of the summer season, whereas control colonies gained weight towards the end of the season. Further investigations are required, but we hypothesise that such effects on both individual foragers and whole colony fitness parameters could ultimately contribute to winter losses of honey bee colonies, particularly in the presence of additional stressors.

Macrophages are abundant in the cochlea; however, their role in hearing loss is not well understood. Insults to the cochlea, such as noise or insertion of a cochlear implant, cause an inflammatory response, which includes activation of tissue-resident macrophages. Activation is characterized by changes in macrophage morphology, mediator expression, and distribution. Evidence from other organs shows activated macrophages can become primed, whereby subsequent insults cause an elevated inflammatory response. Primed macrophages in brain pathologies respond to circulating inflammatory mediators by disproportionate synthesis of inflammatory mediators. This signaling occurs behind an intact blood-brain barrier, similar to the blood-labyrinth barrier in the cochlea. Local tissue damage can occur as the result of mediator release by activated macrophages. Damage is typically localized; however, if it is to structures with limited ability to repair, such as neurons or hair cells within the cochlea, it is feasible that this contributes to the progressive loss of function seen in hearing loss. We propose that macrophages in the cochlea link risk factors and hearing loss. Injury to the cochlea causes local macrophage activation that typically resolves. However, in susceptible individuals, some macrophages enter a primed state. Once primed, these macrophages can be further activated, as a consequence of circulating inflammatory molecules associated with common co-morbidities. Hypothetically, this would lead to further cochlear damage and loss of hearing. We review the evidence for the role of tissue-resident macrophages in the cochlea and propose that cochlear macrophages contribute to the trajectory of hearing loss and warrant further study.

The current methods for diagnosis of acute and chronic infections are complex and skill-intensive. For complex clinical biofilm infections, it can take days from collecting and processing a patient's sample to achieving a result. These aspects place a significant burden on healthcare providers, delay treatment, and can lead to adverse patient outcomes. We report the development and application of a novel multi-excitation Raman spectroscopy-based methodology for the label-free and non-invasive detection of microbial pathogens that can be used with unprocessed clinical samples directly and provide rapid data to inform diagnosis by a medical professional. The method relies on the differential excitation of non-resonant and resonant molecular components in bacterial cells to enhance the molecular finger-printing capability to obtain strain-level distinction in bacterial species. Here, we use this strategy to detect and characterize the respiratory pathogens and as typical infectious agents associated with cystic fibrosis. Planktonic specimens were analyzed both in isolation and in artificial sputum media. The resonance Raman components, excited at different wavelengths, were characterized as carotenoids and porphyrins. By combining the more informative multi-excitation Raman spectra with multivariate analysis (support vector machine) the accuracy was found to be 99.75% for both species (across all strains), including 100% accuracy for drug-sensitive and drug-resistant . The results demonstrate that our methodology based on multi-excitation Raman spectroscopy can underpin the development of a powerful platform for the rapid and reagentless detection of clinical pathogens to support diagnosis by a medical expert, in this case relevant to cystic fibrosis. Such a platform could provide translatable diagnostic solutions in a variety of disease areas and also be utilized for the rapid detection of anti-microbial resistance.

Melioidosis caused by the facultative intracellular pathogen is difficult to treat due to poor intracellular bioavailability of antibiotics and antibiotic resistance. In the absence of novel compounds, polymersome (PM) encapsulation may increase the efficacy of existing antibiotics and reduce antibiotic resistance by promoting targeted, infection-specific intracellular uptake. In this study, we developed PMs composed of widely available poly(ethylene oxide)-polycaprolactone block copolymers and demonstrated their delivery to intracellular infection using multispectral imaging flow cytometry (IFC) and coherent anti-Stokes Raman scattering microscopy. Antibiotics were tightly sequestered in PMs and did not inhibit the growth of free-living . However, on uptake of antibiotic-loaded PMs by infected macrophages, IFC demonstrated PM colocalization with intracellular and a significant inhibition of their growth. We conclude that PMs are a viable approach for the targeted antibiotic treatment of persistent intracellular infection.

The reasons for soft failure after cochlear implantation require investigation. This study proposes a method to study and characterize the tissue response to the array in a case of soft failure in a person undergoing reimplantation.

Bacterial infections are a common cause of morbidity and mortality in the elderly, and particularly in individuals with a neurodegenerative disease. Experimental models of neurodegeneration have shown that LPS-induced systemic inflammation increases neuronal damage, a process thought to be mediated by activation of "primed" microglia. The effects of a real systemic bacterial infection on the innate immune cells in the brain and neuronal networks are less well described, and therefore, in this study we use the ME7 prion model to investigate the alterations in microglia activation and phenotype and synaptic markers in response to a low grade, live bacterial infection. Mice with or without a pre-existing ME7 prion-induced neurodegenerative disease were given a single systemic injection of live at early or mid-stage of disease progression. Immune activation markers CD11b and MHCII and pro-inflammatory cytokines were analyzed 4 weeks post-infection. Systemic infection with resulted in an exaggerated inflammatory response when compared to ME7 prion mice treated with saline. These changes to inflammatory markers were most pronounced at mid-stage disease. Analysis of synaptic markers in ME7 prion mice revealed a significant reduction of genes that are associated with early response in synaptic plasticity, extracellular matrix structure and post-synaptic density, but no further reduction following systemic infection. In contrast, analysis of activity-related neuronal receptors involved in development of learning and memory, such as and , showed a significant decrease in response to systemic bacterial challenge. These changes were observed early in the disease progression and associated with reduced burrowing activity. The exaggerated innate immune activation and altered expression of genes linked to synaptic plasticity may contribute to the onset and/or progression of neurodegeneration.

Neuroinflammation is an integral part of Alzheimer's disease (AD) pathology. Inflammatory mediators can exacerbate the production of amyloid-β (Aβ), the propagation of tau pathology and neuronal loss.

The Fugl-Meyer Assessment (FMA) scale, which is widely used and highly recommended, is an appropriate tool for evaluating poststroke sensorimotor and other possible somatic deficits. It is also well-suited for capturing a dynamic rehabilitation process. The aim of this study was to first translate the entire sensorimotor FMA scale into Romanian using the transcultural and semantic-linguistic adaptations of its official afferent protocols and to validate it using the preliminary clinical evaluation of inter- and intra-rater reliability and relevant concurrent validity.

Tauopathies are a group of disorders in which the deposition of abnormally folded tau protein accompanies neurodegeneration. The development of methods for detection and classification of pathological changes in protein conformation are desirable for understanding the factors that influence the structural polymorphism of aggregates in tauopathies. We have previously demonstrated the utility of Raman spectroscopy for the characterization and discrimination of different protein aggregates, including tau, based on their unique conformational signatures. Building on this, in the present study, we assess the utility of Raman spectroscopy for characterizing and distinguishing different conformers of the same protein which in the case of tau are unique tau strains generated . We now investigate the impact of aggregation environment, cofactors, post-translational modification and primary sequence on the Raman fingerprint of tau fibrils. Using quantitative conformational fingerprinting and multivariate statistical analysis, we found that the aggregation of tau in different buffer conditions resulted in the formation of distinct fibril strains. Unique spectral markers were identified for tau fibrils generated using heparin or RNA cofactors, as well as for phosphorylated tau. We also determined that the primary sequence of the tau monomer influenced the conformational signature of the resulting tau fibril, including 2N4R, 0N3R, K18 and P301S tau variants. These results highlight the conformational polymorphism of tau fibrils, which is reflected in the wide range of associated neurological disorders. Furthermore, the analyses presented in this study provide a benchmark for the Raman spectroscopic characterization of tau strains, which may shed light on how the aggregation environment, cofactors and post-translational modifications influence tau conformation in future studies.

Neuroimmunology in the broadest sense is the study of interactions between the nervous and the immune systems. These interactions play important roles in health from supporting neural development, homeostasis and plasticity to modifying behaviour. Neuroimmunology is increasingly recognised as a field with the potential to deliver a significant positive impact on human health and treatment for neurological and psychiatric disorders. Yet, translation to the clinic is hindered by fundamental knowledge gaps on the underlying mechanisms of action or the optimal timing of an intervention, and a lack of appropriate tools to visualise and modulate both systems. Here we propose ten key disease-agnostic research questions that, if addressed, could lead to significant progress within neuroimmunology in the short to medium term. We also discuss four cross-cutting themes to be considered when addressing each question: i) bi-directionality of neuroimmune interactions; ii) the biological context in which the questions are addressed (e.g. health vs disease vs across the lifespan); iii) tools and technologies required to fully answer the questions; and iv) translation into the clinic. We acknowledge that these ten questions cannot represent the full breadth of gaps in our understanding; rather they focus on areas which, if addressed, may have the most broad and immediate impacts. By defining these neuroimmunology priorities, we hope to unite existing and future research teams, who can make meaningful progress through a collaborative and cross-disciplinary effort.