TMEM106B core deposition associates with TDP-43 pathology and is increased in risk SNP carriers for frontotemporal dementia.

Genetic variation at the transmembrane protein 106B gene (TMEM106B) has been linked to risk of frontotemporal lobar degeneration with TDP-43 inclusions (FTLD-TDP) through an unknown mechanism. We found that presence of the TMEM106B rs3173615 protective genotype was associated with longer survival after symptom onset in a postmortem FTLD-TDP cohort, suggesting a slower disease course. The seminal discovery that filaments derived from TMEM106B is a common feature in aging and, across a range of neurodegenerative disorders, suggests that genetic variants in TMEM106B could modulate disease risk and progression through modulating TMEM106B aggregation. To explore this possibility and assess the pathological relevance of TMEM106B accumulation, we generated a new antibody targeting the TMEM106B filament core sequence. Analysis of postmortem samples revealed that the TMEM106B rs3173615 risk allele was associated with higher TMEM106B core accumulation in patients with FTLD-TDP. In contrast, minimal TMEM106B core deposition was detected in carriers of the protective allele. Although the abundance of monomeric full-length TMEM106B was unchanged, carriers of the protective genotype exhibited an increase in dimeric full-length TMEM106B. Increased TMEM106B core deposition was also associated with enhanced TDP-43 dysfunction, and interactome data suggested a role for TMEM106B core filaments in impaired RNA transport, local translation, and endolysosomal function in FTLD-TDP. Overall, these findings suggest that prevention of TMEM106B core accumulation is central to the mechanism by which the TMEM106B protective haplotype reduces disease risk and slows progression.

Clinicopathologic features of a novel star-shaped transactive response DNA-binding protein 43 (TDP-43) pathology in the oldest old.

Transactive response DNA-binding protein 43 (TDP-43) pathology is categorized as type A-E in frontotemporal lobar degeneration and as type α-ß in Alzheimer disease (AD) based on inclusion type. We screened amygdala slides of 131 cases with varying ages at death, clinical/neuroimaging findings, and AD neuropathologic changes for TDP-43 pathology using anti-phospho-TDP-43 antibodies. Seven cases (5%) only showed atypical TDP-43 inclusions that could not be typed. Immunohistochemistry and immunofluorescence assessed the atypical star-shaped TDP-43 pathology including its distribution, species, cellular localization, and colocalization with tau. All 7 had died at an extremely old age (median: 100 years [IQR: 94-101]) from nonneurological causes and none had dementia (4 cognitively unimpaired, 3 with amnestic mild cognitive impairment). Neuroimaging showed mild medial temporal involvement. Pathologically, the star-shaped TDP-43-positive inclusions were found in medial (subpial) amygdala and, occasionally, in basolateral regions. Hippocampus only showed TDP-43-positive neurites in the fimbria and subiculum while the frontal lobe was free of TDP-43 inclusions. The star-shaped inclusions were better detected with antibodies against N-terminal than C-terminal TDP-43. Double-labeling studies confirmed deposition of TDP-43 within astrocytes and colocalization with tau. We have identified a novel TDP-43 pathology with star-shaped morphology associated with superaging, with a homogeneous clinicopathologic picture, possibly representing a novel, true aging-related TDP-43 pathology.

Investigating the Pathogenic Interplay of Alpha-Synuclein, Tau, and Amyloid Beta in Lewy Body Dementia: Insights from Viral-Mediated Overexpression in Transgenic Mouse Models.

Lewy body dementia (LBD) is an often misdiagnosed and mistreated neurodegenerative disorder clinically characterized by the emergence of neuropsychiatric symptoms followed by motor impairment. LBD falls within an undefined range between Alzheimer's disease (AD) and Parkinson's disease (PD) due to the potential pathogenic synergistic effects of tau, beta-amyloid (Aß), and alpha-synuclein (αsyn). A lack of reliable and relevant animal models hinders the elucidation of the molecular characteristics and phenotypic consequences of these interactions. Here, the goal was to evaluate whether the viral-mediated overexpression of αsyn in adult hTau and APP/PS1 mice or the overexpression of tau in Line 61 hThy1-αsyn mice resulted in pathology and behavior resembling LBD. The transgenes were injected intravenously via the tail vein using AAV-PHP.eB in 3-month-old hThy1-αsyn, hTau, or APP/PS1 mice that were then aged to 6-, 9-, and 12-months-old for subsequent phenotypic and histological characterization. Although we achieved the widespread expression of αsyn in hTau and tau in hThy1-αsyn mice, no αsyn pathology in hTau mice and only mild tau pathology in hThy1-αsyn mice was observed. Additionally, cognitive, motor, and limbic behavior phenotypes were not affected by overexpression of the transgenes. Furthermore, our APP/PS1 mice experienced premature deaths starting at 3 months post-injection (MPI), therefore precluding further analyses at later time points. An evaluation of the remaining 3-MPI indicated no αsyn pathology or cognitive and motor behavioral changes. Taken together, we conclude that the overexpression of αsyn in hTau and APP/PS1 mice and tau in hThy1-αsyn mice does not recapitulate the behavioral and neuropathological phenotypes observed in LBD.

Poly(GR) interacts with key stress granule factors promoting its assembly into cytoplasmic inclusions.

C9orf72 repeat expansions are the most common genetic cause of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). Poly(GR) proteins are toxic to neurons by forming cytoplasmic inclusions that sequester RNA-binding proteins including stress granule (SG) proteins. However, little is known of the factors governing poly(GR) inclusion formation. Here, we show that poly(GR) infiltrates a finely tuned network of protein-RNA interactions underpinning SG formation. It interacts with G3BP1, the key driver of SG assembly and a protein we found is critical for poly(GR) inclusion formation. Moreover, we discovered that N6-methyladenosine (m6A)-modified mRNAs and m6A-binding YTHDF proteins not only co-localize with poly(GR) inclusions in brains of c9FTD/ALS mouse models and patients with c9FTD, they promote poly(GR) inclusion formation via the incorporation of RNA into the inclusions. Our findings thus suggest that interrupting interactions between poly(GR) and G3BP1 or YTHDF1 proteins or decreasing poly(GR) altogether represent promising therapeutic strategies to combat c9FTD/ALS pathogenesis.

Diffuse argyrophilic grain disease with TDP-43 proteinopathy and neuronal intermediate filament inclusion disease: FTLD with mixed tau, TDP-43 and FUS pathologies.

Frontotemporal lobar degeneration (FTLD) is a group of disorders characterized by degeneration of the frontal and temporal lobes, leading to progressive decline in language, behavior, and motor function. FTLD can be further subdivided into three main subtypes, FTLD-tau, FTLD-TDP and FTLD-FUS based which of the three major proteins - tau, TDP-43 or FUS - forms pathological inclusions in neurons and glia. In this report, we describe an 87-year-old woman with a 7-year history of cognitive decline, hand tremor and gait problems, who was thought to have Alzheimer's disease. At autopsy, histopathological analysis revealed severe neuronal loss, gliosis and spongiosis in the medial temporal lobe, orbitofrontal cortex, cingulate gyrus, amygdala, basal forebrain, nucleus accumbens, caudate nucleus and anteromedial thalamus. Tau immunohistochemistry showed numerous argyrophilic grains, pretangles, thorn-shaped astrocytes, and ballooned neurons in the amygdala, hippocampus, parahippocampal gyrus, anteromedial thalamus, insular cortex, superior temporal gyrus and cingulate gyrus, consistent with diffuse argyrophilic grain disease (AGD). TDP-43 pathology in the form of small, dense, rounded neuronal cytoplasmic inclusion with few short dystrophic neurites was observed in the limbic regions, superior temporal gyrus, striatum and midbrain. No neuronal intranuclear inclusion was observed. Additionally, FUS-positive inclusions were observed in the dentate gyrus. Compact, eosinophilic intranuclear inclusions, so-called "cherry spots," that were visible on histologic stains were immunopositive for α-internexin. Taken together, the patient had a mixed neurodegenerative disease with features of diffuse AGD, TDP-43 proteinopathy and neuronal intermediate filament inclusion disease. She met criteria for three subtypes of FTLD: FTLD-tau, FTLD-TDP and FTLD-FUS. Her amnestic symptoms that were suggestive of Alzheimer's type dementia are best explained by diffuse AGD and medial temporal TDP-43 proteinopathy, and her motor symptoms were likely explained by neuronal loss and gliosis due to tau pathology in the substantia nigra. This case underscores the importance of considering multiple proteinopathies in the diagnosis of neurodegenerative diseases.

Diagnosis of Alzheimer Disease and Tauopathies on Whole-Slide Histopathology Images Using a Weakly Supervised Deep Learning Algorithm.

Neuropathologic assessment during autopsy is the gold standard for diagnosing neurodegenerative disorders. Neurodegenerative conditions, such as Alzheimer disease (AD) neuropathological change, are a continuous process from normal aging rather than categorical; therefore, diagnosing neurodegenerative disorders is a complicated task. We aimed to develop a pipeline for diagnosing AD and other tauopathies, including corticobasal degeneration (CBD), globular glial tauopathy, Pick disease, and progressive supranuclear palsy. We used a weakly supervised deep learning-based approach called clustering-constrained-attention multiple-instance learning (CLAM) on the whole-slide images (WSIs) of patients with AD (n = 30), CBD (n = 20), globular glial tauopathy (n = 10), Pick disease (n = 20), and progressive supranuclear palsy (n = 20), as well as nontauopathy controls (n = 21). Three sections (A: motor cortex; B: cingulate gyrus and superior frontal gyrus; and C: corpus striatum) that had been immunostained for phosphorylated tau were scanned and converted to WSIs. We evaluated 3 models (classic multiple-instance learning, single-attention-branch CLAM, and multiattention-branch CLAM) using 5-fold cross-validation. Attention-based interpretation analysis was performed to identify the morphologic features contributing to the classification. Within highly attended regions, we also augmented gradient-weighted class activation mapping to the model to visualize cellular-level evidence of the model's decisions. The multiattention-branch CLAM model using section B achieved the highest area under the curve (0.970 ± 0.037) and diagnostic accuracy (0.873 ± 0.087). A heatmap showed the highest attention in the gray matter of the superior frontal gyrus in patients with AD and the white matter of the cingulate gyrus in patients with CBD. Gradient-weighted class activation mapping showed the highest attention in characteristic tau lesions for each disease (eg, numerous tau-positive threads in the white matter inclusions for CBD). Our findings support the feasibility of deep learning-based approaches for the classification of neurodegenerative disorders on WSIs. Further investigation of this method, focusing on clinicopathologic correlations, is warranted.

An analysis of a video education campaign on COVID-19 for healthcare workers in Africa delivered through Facebook.

INTRODUCTION: The COVID-19 pandemic required rapid dissemination of accurate information across the world to both healthcare workers and the general public. Social media represents an opportunity to undertake this. The aim of this study was to analyse a healthcare worker education campaign in Africa delivered through the social media platform Facebook and discuss the feasibility of this approach for future healthcare workers and public health campaigns. METHODS: The campaign ran from June 2020 to January 2021. The Facebook Ad Manager suite was used to extract data in July 2021. Videos were analysed for total and individual video reach, impressions, 3-second video plays, 50% plays and 100% plays. The geographic use of the videos and age and gender breakdown was also analysed. RESULTS: Total reach of the Facebook campaign was 6,356,846 and total impressions was 12,767,118. The video with the highest reach was 'Hand washing steps for health workers' with a reach of 1,479,603. The total campaign 3-second plays were 2,189,460 decreasing to 77,120 for 100% play duration. DISCUSSION: Facebook advertising campaigns may have the ability to reach large populations and achieve a range of engagement outcomes that would be more cost effective and have greater reach when compared with traditional media. The outcome of this campaign has shown the potential of social media's use in public health information, medical education and professional development.

The availability of general practice in Ireland's Mid-West Region: does the 'Inverse Care Law' still apply?

INTRODUCTION: The 'Inverse Care Law' suggests the availability of good medical care tends to vary inversely with the needs of the local population. Dr Julian Tudor Hart's observations related to lack of access to care for those in both socially deprived and geographically remote areas. In this study, we aim to examine if the 'Inverse Care Law' is still relevant to GP service provision in the Mid-West of Ireland. METHODS: GP clinic locations in Limerick and Clare were identified using the Health Service Executive (HSE) Service Finder and geocoded. GeoHive.ie was used to determine Electoral District (ED) centroids across the Mid-West. The shortest linear distance to a GP clinic was calculated for each ED. PobalMaps.ie was used to determine population and social deprivation scores of each ED. RESULTS: In total, 122 GP practices were identified across 324 EDs. The average travel distance to a GP clinic in the Mid-West is 4.7 km. Limerick City EDs had the smallest patient population per GP clinic and were all found to be within 1.5 km of a GP clinic. Proximity to GP clinics did not correlate with deprivation. However, by removing GP clinics from the analyses, it was possible to determine how vulnerable different areas (rural vs urban, deprived vs affluent) are to potential changes in GP clinic availability in the future. DISCUSSION: People living in urban areas such a Limerick City have improved geographic accessibility to GP clinics compared with their rural counterparts. However, within urban areas assessed, GP clinics were rarely found in deprived areas. Therefore, remote and urban-deprived areas are far more vulnerable to negative proximity effects secondary to practice closures, suggesting the principles of the 'Inverse Care Law' may still be active in the Mid-West of Ireland.

GPs at the Edge: a quantitative description of Irish Rural General Practice.

INTRODUCTION: Currently, more than 1.6 million Irish people live rurally. Rural populations in Ireland are older and have more health needs compared with younger urban areas. Meanwhile, since 1982, the proportion of general practices in rural areas has decreased by 10%. In this study, we look at new survey data to investigate the needs and challenges of rural general practice in Ireland. METHODS: This study will make use of survey responses from the 2021 membership survey by the Irish College of General Practitioners (ICGP). The anonymous, online, survey was sent by email to the ICGP membership in late 2021, with a series of questions pertaining to practice location, and prior experience of living and working in a rural area designed specifically for this project. A series of statistical tests will be undertaken as appropriate for the data. RESULTS: This study is ongoing; we aim to present data on the demographics of those working in rural general practice and related factors. DISCUSSION: Previous research has shown that people who grew up or trained in rural areas are more likely to work there after qualifying. As the analysis of this survey continues, it will be important to see if this pattern is evident here as well.

GPs at the Edge: GATE, a qualitative investigation into the experience of delivering care in Irish Rural General Practice.

INTRODUCTION: Over a third of Irish people live rurally. However, only a fifth of Irish general practices are located in rural communities and longstanding issues such as distance to other health services, professional isolation, and recruitment and retention of rural healthcare professionals (HCPs) threaten rural general practice's sustainability. This ongoing study seeks to understand what it is like to provide care to Ireland's rural and remote populations. METHODS: This is a qualitative study, consisting of semi-structured interviews with GPs and practice nurses working in practices that serve rural populations across Ireland. Topic guides were developed after a literature review and a series of pilot interviews. Interviews are scheduled to be finished in February 2022. RESULTS: This study is ongoing so results are yet to be finalised. Initial key themes include a great level of professional satisfaction that GPs and practice nurses experience from caring for entire families from the 'cradle to grave' and from the complex issues they face in practice. A rural general practice acts as the medical port-of-call for patients, with both practice nurses and GPs having experiences with emergency and pre-hospital medicine. A key difficulty identified is access to secondary and tertiary care services, with distance to services and high demand as the main barriers. DISCUSSION: Working in rural general practice gives HCPs great professional satisfaction but access to other health services remains a challenge. Final conclusions may be compared with other delegates' experiences.

Supporting GPs and people with hypertension to maximise medication use to control blood pressure: Protocol for a pilot cluster RCT of the MIAMI intervention.

Background: Hypertension is one of the most important risk factors for stroke and heart disease. Recent international guidelines have stated that 'poor adherence to treatment - in addition to physician inertia - is the most important cause of poor blood pressure control'. The MaxImising Adherence, Minimising Inertia (MIAMI) intervention, which has been developed using a systematic, theoretical, user-centred approach, aims to support general practitioners (GPs) and people with hypertension to maximise medication use, through the facilitation of adequate information exchange within consultations about long-term antihypertensive medication use and adherence skill development. The aim of the MIAMI pilot cluster randomised controlled trial (RCT) is to gather and analyse feasibility data to allow us to (1) refine the intervention, and (2) determine the feasibility of a definitive RCT. Methods: GP practices (n = 6) will be recruited and randomised to the intervention arm (n = 3) or usual care control arm (n = 3). Each practice will recruit 10 patient participants. For a patient to be eligible they must have a diagnosis of hypertension, be on two or more anti-hypertensive medications, must not be achieving recommended blood pressure levels, and be over the age of 65 years. Participants in the intervention arm will meet their GP and receive the MIAMI intervention twice over three months. Quantitative data collection will take place at baseline and three month follow up. A pilot health economic analysis and a qualitative sub-study will also be incorporated into the study. Discussion: This pilot cluster RCT of the MIAMI intervention will allow us to gather valuable acceptability and feasibility data to further refine the intervention so it optimally designed for both GP and patient use. In particular, the qualitative component will provide an insight into GP and patient experiences of using the intervention.

Two FTD-ALS genes converge on the endosomal pathway to induce TDP-43 pathology and degeneration.

Frontotemporal dementia and amyotrophic lateral sclerosis (FTD-ALS) are associated with both a repeat expansion in the C9orf72 gene and mutations in the TANK-binding kinase 1 (TBK1) gene. We found that TBK1 is phosphorylated in response to C9orf72 poly(Gly-Ala) [poly(GA)] aggregation and sequestered into inclusions, which leads to a loss of TBK1 activity and contributes to neurodegeneration. When we reduced TBK1 activity using a TBK1-R228H (Arg228→His) mutation in mice, poly(GA)-induced phenotypes were exacerbated. These phenotypes included an increase in TAR DNA binding protein 43 (TDP-43) pathology and the accumulation of defective endosomes in poly(GA)-positive neurons. Inhibiting the endosomal pathway induced TDP-43 aggregation, which highlights the importance of this pathway and TBK1 activity in pathogenesis. This interplay between C9orf72, TBK1, and TDP-43 connects three different facets of FTD-ALS into one coherent pathway.

Galactosylceramidase deficiency and pathological abnormalities in cerebral white matter of Krabbe disease.

Krabbe Disease (KD) is an autosomal recessive disorder that results from loss-of-function mutations in the GALC gene, which encodes lysosomal enzyme galactosylceramidase (GALC). Functional deficiency of GALC is toxic to myelin-producing cells, which leads to progressive demyelination in both the central and peripheral nervous systems. It is hypothesized that accumulation of psychosine, which can only be degraded by GALC, is a primary initiator of pathologic cascades. Despite the central role of GALC in KD pathomechanism, investigations of GALC deficiency at a protein level are largely absent, due in part, to the lack of sensitive antibodies in the field. Leveraging two custom antibodies that can detect GALC at endogenous levels, we demonstrated that GALC protein is predominantly localized to oligodendrocytes in cerebral white matter of an infant brain, consistent with its functional role in myelination. Mature GALC could also be quantitatively detected as a 26 kDa band by western blotting and correlated to enzyme activity in brain tissues. The p.Ile562Thr polymorphic variant, which is over-represented in the KD population, was associated with reduced mature GALC protein and activity. In three infantile KD cases, homozygous null mutations in GALC lead to deficiency in total GALC protein and activity. Interestingly, although GALC activity was absent, normal levels of total GALC protein were detected by a sandwich ELISA using our custom antibodies in a later-onset KD brain, which suggests that the assay has the potential to differentiate infantile- and later-onset KD cases. Among the infantile KD cases, we quantified a 5-fold increase in psychosine levels, and observed increased levels of acid ceramidase, a key enzyme for psychosine production, and hyperglycosylated lysosomal-associated membrane protein 1, a marker for lysosomal activation, in periventricular white matter, a major pathological brain region, when compared with age-matched normal controls. While near complete demyelination was observed in these cases, we quantified that an early-infantile case (age of death at 10 months) had about 3-fold increases in both globoid cells, a pathological hallmark for KD, and CD8-positive T lymphocytes, a pathological marker for multiple sclerosis, in the white matter when compared with a slower progressing infantile case (age of death at 21 months), which suggests a positive correlation between clinical severity and neuropathology. Taken together, our findings have advanced the understanding of GALC protein biology in the context of normal and KD brain white matter. We also revealed new neuropathological changes that may provide insights to understand KD pathogenesis.

Phosphorylated tau sites that are elevated in Alzheimer's disease fluid biomarkers are visualized in early neurofibrillary tangle maturity levels in the post mortem brain.

INTRODUCTION: Alzheimer's disease (AD) biomarkers are increasingly more reliable in predicting neuropathology. To facilitate interpretation of phosphorylated tau sites as an early fluid biomarker, we sought to characterize which neurofibrillary tangle maturity levels (pretangle, intermediary 1, mature tangle, intermediary 2, and ghost tangle) are recognized. METHODS: We queried the Florida Autopsied Multi-Ethnic (FLAME) cohort for cases ranging from Braak stages I through VI, excluding non-AD neuropathologies and tauopathies. Thioflavin-S staining was compared to immunohistochemical measures of phosphorylated threonine (pT) 181, pT205, pT217, and pT231 in two hippocampal subsectors across n = 24 cases. RESULTS: Each phosphorylated tau site immunohistochemically labeled early neurofibrillary tangle maturity levels compared to advanced levels recognized by thioflavin-S. Hippocampal burden generally increased with each Braak stage. DISCUSSION: These results provide neurobiologic evidence that these phosphorylated tau fluid biomarker sites are present during early neurofibrillary tangle maturity levels and may explain why these fluid biomarker measures are observed before symptom onset. HIGHLIGHTS: Immunohistochemical evaluation of four phosphorylated tau fluid biomarker sites. Earlier neurofibrillary tangle maturity levels recognized by phosphorylated tau in proline-rich region. Advanced tangle pathology is elevated in the subiculum compared to the cornu ammonis 1 of the hippocampus. Novel semi-quantitative frequency to calculate tangle maturity frequency.

Plasma PolyQ-ATXN3 Levels Associate With Cerebellar Degeneration and Behavioral Abnormalities in a New AAV-Based SCA3 Mouse Model.

Spinocerebellar ataxia type 3 (SCA3) is a dominantly inherited cerebellar ataxia caused by the expansion of a polyglutamine (polyQ) repeat in the gene encoding ATXN3. The polyQ expansion induces protein inclusion formation in the neurons of patients and results in neuronal degeneration in the cerebellum and other brain regions. We used adeno-associated virus (AAV) technology to develop a new mouse model of SCA3 that recapitulates several features of the human disease, including locomotor defects, cerebellar-specific neuronal loss, polyQ-expanded ATXN3 inclusions, and TDP-43 pathology. We also found that neurofilament light is elevated in the cerebrospinal fluid (CSF) of the SCA3 animals, and the expanded polyQ-ATXN3 protein can be detected in the plasma. Interestingly, the levels of polyQ-ATXN3 in plasma correlated with measures of cerebellar degeneration and locomotor deficits in 6-month-old SCA3 mice, supporting the hypothesis that this factor could act as a biomarker for SCA3.

Lessons learned from a pandemic: implications for a combined exercise and educational programme for medical students.

BACKGROUND: The 'MED-WELL' programme is a combined exercise and educational intervention designed to promote well-being among medical students and educate students about prescribing exercise as medicine in clinical practice. Due to COVID-19 public health restrictions of social distancing the 'MED-WELL' programme was offered online instead of in-person in 2021. The aim of this study is to compare the experiences of participants in the 'MED-WELL' programme online to those that previously participated in the same programme in-person to understand the student experience and optimize programme delivery. METHODS: Purposive sampling was used to recruit 20 participants to a qualitative study using semi-structured interviews. Ten study participants took part in the 'MED-WELL' programme when it was offered in-person, and the other ten study participants took part in the programme when it was offered online. All interviews were audio-recorded and transcribed using Microsoft Teams. A combined inductive and deductive approach was used for analysis. An inductive thematic analysis was utilized to categorize data into higher order codes, themes, and overarching themes. The theory of online learning provided the theoretical framework for a deductive approach. RESULTS: Analysis of the data produced five overarching themes: 'student-student', 'student-teacher', 'student-content', 'student-environment', and 'effects of a pandemic'. The first four themes detail distinct types of interaction that participants had with various entities of the 'MED-WELL' programme and the effects that these interactions had on participant experiences. 'Effects of a pandemic' refers to the context of delivering the 'MED-WELL' programme online during a pandemic and how this mode of delivery influenced participants and the programme. CONCLUSIONS: Optimizing the 'MED-WELL' programme relies on an understanding of how participants interact with different entities of the programme and are motivated to attend and engage. Participants tended to favour an in-person mode of delivery, however certain advantages of delivering the programme online were also identified. The findings from this study can be used to inform similar experiential and educational exercise interventions, and may help plan for potential future restrictions on in-person educational and exercise-based programmes.

Alzheimer's disease and progressive supranuclear palsy share similar transcriptomic changes in distinct brain regions.

Vast numbers of differentially expressed genes and perturbed networks have been identified in Alzheimer's disease (AD), however, neither disease nor brain region specificity of these transcriptome alterations has been explored. Using RNA-Seq data from 231 temporal cortex and 224 cerebellum samples from patients with AD and progressive supranuclear palsy (PSP), a tauopathy, we identified a striking correlation in the directionality and magnitude of gene expression changes between these 2 neurodegenerative proteinopathies. Further, the transcriptomic changes in AD and PSP brains ware highly conserved between the temporal and cerebellar cortices, indicating that highly similar transcriptional changes occur in pathologically affected and grossly less affected, albeit functionally connected, areas of the brain. Shared up- or downregulated genes in AD and PSP are enriched in biological pathways. Many of these genes also have concordant protein changes and evidence of epigenetic control. These conserved transcriptomic alterations of 2 distinct proteinopathies in brain regions with and without significant gross neuropathology have broad implications. AD and other neurodegenerative diseases are likely characterized by common disease or compensatory pathways with widespread perturbations in the whole brain. These findings can be leveraged to develop multifaceted therapies and biomarkers that address these common, complex, and ubiquitous molecular alterations in neurodegenerative diseases.

Identifying the gaps in Irish cancer care: Patient, public and providers' perspectives.

BACKGROUND: The University of Limerick Cancer network (ULCaN) was established in 2019 with funding from the Health Research Institute at the University of Limerick in order to build a network between individuals in academia, primary and secondary care and the general public so that cancer services can be coordinated and more effective. The aim of this paper is to outline our experience of engaging with stakeholders to identify gaps in the cancer journey locally. METHODS: Four focus group discussions were conducted with patients; their carers; members of the public; and healthcare providers with 2 main aims: 1) to investigate gaps in cancer services; 2) to identify knowledge, attitudes and opportunities available to promote cancer research. The focus groups were audio recorded, transcribed and thematically analysed. RESULTS: 15 themes within the topics of cancer care, palliation, communication, clinical trials, diet and exercise and public and patient involvement in research and advocacy were identified. These include directing people to reliable information and navigating misinformation and stigma linked with cancer, promoting awareness of clinical trials and palliative care services and improving communication when multiple healthcare providers are involved. CONCLUSION: The need to make more coherent, efficient and integrated cancer research amongst local stakeholders was evident. Embedding patients and members of the public into ULCaN is an important deliverable for collaborative research.

Microglial lysosome dysfunction contributes to white matter pathology and TDP-43 proteinopathy in GRN-associated FTD.

Loss-of-function mutations in the progranulin gene (GRN), which encodes progranulin (PGRN), are a major cause of frontotemporal dementia (FTD). GRN-associated FTD is characterized by TDP-43 inclusions and neuroinflammation, but how PGRN loss causes disease remains elusive. We show that Grn knockout (KO) mice have increased microgliosis in white matter and an accumulation of myelin debris in microglial lysosomes in the same regions. Accumulation of myelin debris is also observed in white matter of patients with GRN-associated FTD. In addition, our findings also suggest that PGRN insufficiency in microglia leads to impaired lysosomal-mediated clearance of myelin debris. Finally, Grn KO mice that are deficient in cathepsin D (Ctsd), a key lysosomal enzyme, have augmented myelin debris and increased neuronal TDP-43 pathology. Together, our data strongly imply that PGRN loss affects microglial activation and lysosomal function, resulting in the accumulation of myelin debris and contributing to TDP-43 pathology.