Long-term effects of SARS-CoV-2 infection in patients with and without chemosensory disorders at disease onset: a psychophysical and magnetic resonance imaging exploratory study.

A preserved sense of smell and taste allows us to understand many environmental "messages" and results in meaningfully improvements to quality of life. With the COVID-19 pandemic, it became clear how important these senses are for social and nutritional status and catapulted this niche chemosensory research area towards widespread interest. In the current exploratory work, we assessed two groups of post-COVID-19 patients who reported having had (Group 1) or not (Group 2) a smell/taste impairment at the disease onset. The aim was to compare them using validated smell and taste tests as well as with brain magnetic resonance imaging volumetric analysis. Normative data were used for smell scores comparison and a pool of healthy subjects, recruited before the pandemic, served as controls for taste scores. The majority of patients in both groups showed an olfactory impairment, which was more severe in Group 1 (median UPSIT scores: 24.5 Group 1 vs 31.0 Group 2, p = 0.008), particularly among women (p = 0.014). No significant differences emerged comparing taste scores between Group 1 and Group 2, but dysgeusia was only present in Group 1 patients. However, for taste scores, a significant difference was found between Group 1 and controls (p = 0.005). No MRI anatomical abnormalities emerged in any patients while brain volumetric analysis suggested a significant difference among groups for the right caudate nucleus (p = 0.028), although this was not retained following Benjamini-Hochberg correction. This exploratory study could add new information in COVID-19 chemosensory long-lasting impairment and address future investigations on the post-COVID-19 patients' research.

Two-pore potassium channel TREK-1 (K2P2.1) regulates NLRP3 inflammasome activity in macrophages.

Because of the importance of potassium efflux in inflammasome activation, we investigated the role of the two-pore potassium (K2P) channel TREK-1 in macrophage inflammasome activity. Using primary alveolar macrophages (AMs) and bone marrow-derived macrophages (BMDMs) from wild-type (wt) and TREK-1-/- mice, we measured responses to inflammasome priming [using lipopolysaccharide (LPS)] and activation (LPS + ATP). We measured IL-1ß, caspase-1, and NLRP3 via ELISA and Western blot. A membrane-permeable potassium indicator was used to measure potassium efflux during ATP exposure, and a fluorescence-based assay was used to assess changes in membrane potential. Inflammasome activation induced by LPS + ATP increased IL-1ß secretion in wt AMs, whereas activation was significantly reduced in TREK-1-/- AMs. Priming of BMDMs using LPS was not affected by either genetic deficiency or pharmacological inhibition of TREK-1 with Spadin. Cleavage of caspase-1 following LPS + ATP treatment was significantly reduced in TREK-1-/- BMDMs. The intracellular potassium concentration in LPS-primed wt BMDMs was significantly lower compared with TREK-1-/- BMDMs or wt BMDMs treated with Spadin. Conversely, activation of TREK-1 with BL1249 caused a decrease in intracellular potassium in wt BMDMs. Treatment of LPS-primed BMDMs with ATP caused a rapid reduction in intracellular potassium levels, with the largest change observed in TREK-1-/- BMDMs. Intracellular K+ changes were associated with changes in the plasma membrane potential (Em), as evidenced by a more depolarized Em in TREK-1-/- BMDMs compared with wt, and Em hyperpolarization upon TREK-1 channel opening with BL1249. These results suggest that TREK-1 is an important regulator of NLRP3 inflammasome activation in macrophages.NEW & NOTEWORTHY Because of the importance of potassium efflux in inflammasome activation, we investigated the role of the two-pore potassium (K2P) channel TREK-1 in macrophage inflammasome activity. Using primary alveolar macrophages and bone marrow-derived macrophages from wild-type and TREK-1-/- mice, we measured responses to inflammasome priming (using LPS) and activation (LPS + ATP). Our results suggest that TREK-1 is an important regulator of NLRP3 inflammasome activation in macrophages.

Impact of Coronavirus Disease-era Clinical Trial Reform on Cancer Trial Access in Rural/Underserved Regions of the Midwest.

OBJECTIVES: The coronavirus disease 2019 pandemic refocused the cancer community on bringing clinical trials closer to patients and increasing access for traditionally underserved communities. Pandemic-era deregulation increased flexibility with telemedicine visits, less frequent testing, and the ability to have tests done locally. This study evaluates the impact of 2020 cancer clinical trial reform on trial accessibility in rural/underserved regions of the Midwest. METHODS: Publicly available clinicaltrials.gov data was accessed from January 1, 2018 to September 30, 2022 for the 3 leading causes of new cancer cases in Kentucky, Tennessee, Illinois, and Indiana. Interventional trials were categorized based on location using corresponding "Rural-Urban Commuting Area" codes (urban/metropolitan, suburban/micropolitan, small town/rural, and isolated/rural) and categorized as pre versus postpandemic (using March 15, 2020, when national regulatory guidelines were modified). Locations of trial offerings from pre and postpandemic dates were analyzed by paired t test. Comparison of trial location category by state and cancer type was analyzed by 1-way analysis of variance with pairwise multiple comparisons made using the Tukey-Kramer method. RESULTS: Pandemic-era deregulation had no impact on increasing trial availability in suburban and small-town/rural locales ( P = 0.1259). Only 18% of trials were offered outside of urban areas, with 15% in suburban and 3% in small town/rural areas. Results varied by state ( P < 0.0001) with Illinois offering the most suburban and small-town trial availability (27%) compared with Kentucky, Indiana, and Tennessee (18%, 6%, and 2%, respectively). Trial availability in rural versus urban areas did not differ by cancer type ( P = 0.07197). CONCLUSIONS: More work must be done to increase access to cancer clinical trials in rural and suburban areas of the United States.

Intranasally delivered mesenchymal stromal cells decrease glial inflammation early in prion disease.

Mesenchymal stromal cells (MSCs) are an intriguing avenue for the treatment of neurological disorders due to their ability to migrate to sites of neuroinflammation and respond to paracrine signaling in those sites by secreting cytokines, growth factors, and other neuromodulators. We potentiated this ability by stimulating MSCs with inflammatory molecules, improving their migratory and secretory properties. We investigated the use of intranasally delivered adipose-derived MSCs (AdMSCs) in combating prion disease in a mouse model. Prion disease is a rare, lethal neurodegenerative disease that results from the misfolding and aggregation of the prion protein. Early signs of this disease include neuroinflammation, activation of microglia, and development of reactive astrocytes. Later stages of disease include development of vacuoles, neuronal loss, abundant aggregated prions, and astrogliosis. We demonstrate the ability of AdMSCs to upregulate anti-inflammatory genes and growth factors when stimulated with tumor necrosis factor alpha (TNFα) or prion-infected brain homogenates. We stimulated AdMSCs with TNFα and performed biweekly intranasal deliveries of AdMSCs on mice that had been intracranially inoculated with mouse-adapted prions. At early stages in disease, animals treated with AdMSCs showed decreased vacuolization throughout the brain. Expression of genes associated with Nuclear Factor-kappa B (NF-κB) and Nod-Like Receptor family pyrin domain containing 3 (NLRP3) inflammasome signaling were decreased in the hippocampus. AdMSC treatment promoted a quiescent state in hippocampal microglia by inducing changes in both number and morphology. Animals that received AdMSCs showed a decrease in both overall and reactive astrocyte number, and morphological changes indicative of homeostatic astrocytes. Although this treatment did not prolong survival or rescue neurons, it demonstrates the benefits of MSCs in combatting neuroinflammation and astrogliosis.

A multiplexed, paired-pooled droplet digital PCR assay for detection of SARS-CoV-2 in saliva.

In response to the SARS-CoV-2 pandemic, we developed a multiplexed, paired-pool droplet digital PCR (MP4) screening assay. Key features of our assay are the use of minimally processed saliva, 8-sample paired pools, and reverse-transcription droplet digital PCR (RT-ddPCR) targeting the SARS-CoV-2 nucleocapsid gene. The limit of detection was determined to be 2 and 12 copies per µl for individual and pooled samples, respectively. Using the MP4 assay, we routinely processed over 1,000 samples a day with a 24-h turnaround time and over the course of 17 months, screened over 250,000 saliva samples. Modeling studies showed that the efficiency of 8-sample pools was reduced with increased viral prevalence and that this could be mitigated by using 4-sample pools. We also present a strategy for, and modeling data supporting, the creation of a third paired pool as an additional strategy to employ under high viral prevalence.

Comparative site-specific N-glycoproteome analysis reveals aberrant N-glycosylation and gives insights into mannose-6-phosphate pathway in cancer.

N-glycosylation is implicated in cancers and aberrant N-glycosylation is recognized as a hallmark of cancer. Here, we mapped and compared the site-specific N-glycoproteomes of colon cancer HCT116 cells and isogenic non-tumorigenic DNMT1/3b double knockout (DKO1) cells using Fbs1-GYR N-glycopeptide enrichment technology and trapped ion mobility spectrometry. Many significant changes in site-specific N-glycosylation were revealed, providing a molecular basis for further elucidation of the role of N-glycosylation in protein function. HCT116 cells display hypersialylation especially in cell surface membrane proteins. Both HCT116 and DKO1 show an abundance of paucimannose and 80% of paucimannose-rich proteins are annotated to reside in exosomes. The most striking N-glycosylation alteration was the degree of mannose-6-phosphate (M6P) modification. N-glycoproteomic analyses revealed that HCT116 displays hyper-M6P modification, which was orthogonally validated by M6P immunodetection. Significant observed differences in N-glycosylation patterns of the major M6P receptor, CI-MPR in HCT116 and DKO1 may contribute to the hyper-M6P phenotype of HCT116 cells. This comparative site-specific N-glycoproteome analysis provides a pool of potential N-glycosylation-related cancer biomarkers, but also gives insights into the M6P pathway in cancer.

Detailed statistical analysis plan for a randomised controlled trial of the effects of a modified muscle sparing posterior technique (SPAIRE) in hip hemiarthroplasty for displaced intracapsular fractures on post-operative function compared to a standard lateral approach: HemiSPAIRE.

BACKGROUND: The HemiSPAIRE trial is being conducted to determine whether a modified muscle sparing technique (SPAIRE-"Save Piriformis and Internus, Repairing Externus") in hip hemiarthroplasty brings clinical benefits compared to the standard lateral technique in adults aged 60 years or older, with a displaced intracapsular hip fracture. This article describes the detailed statistical analysis plan for the trial.  METHODS AND DESIGN: HemiSPAIRE is a definitive, pragmatic, superiority, multicentre, randomised controlled trial (with internal pilot) with two parallel groups. Participants, ward staff and all research staff involved in post-operative assessments are blinded to allocation. This article describes in detail (1) the primary and secondary outcomes; (2) the statistical analysis principles, including a survivor average causal effect (SACE) method chosen specifically to address the issue of potential bias from differential survival between trial arms, which was seen from data review by the Trial Steering Committee, the participants that will be included in each analysis, the covariates that will be included in each analysis, and how the results will be presented; (3) planned main analysis of the primary outcome; (4) planned analyses of the secondary outcomes; and (5) planned additional analyses of the primary and secondary outcomes. TRIAL REGISTRATION: ClinicalTrials.gov NCT04095611. Registered on 19 September 2019.

A microbial transporter of the dietary antioxidant ergothioneine.

Low-molecular-weight (LMW) thiols are small-molecule antioxidants required for the maintenance of intracellular redox homeostasis. However, many host-associated microbes, including the gastric pathogen Helicobacter pylori, unexpectedly lack LMW-thiol biosynthetic pathways. Using reactivity-guided metabolomics, we identified the unusual LMW thiol ergothioneine (EGT) in H. pylori. Dietary EGT accumulates to millimolar levels in human tissues and has been broadly implicated in mitigating disease risk. Although certain microorganisms synthesize EGT, we discovered that H. pylori acquires this LMW thiol from the host environment using a highly selective ATP-binding cassette transporter-EgtUV. EgtUV confers a competitive colonization advantage in vivo and is widely conserved in gastrointestinal microbes. Furthermore, we found that human fecal bacteria metabolize EGT, which may contribute to production of the disease-associated metabolite trimethylamine N-oxide. Collectively, our findings illustrate a previously unappreciated mechanism of microbial redox regulation in the gut and suggest that inter-kingdom competition for dietary EGT may broadly impact human health.

Development of HEK-293 Cell Lines Constitutively Expressing Flaviviral Antigens for Use in Diagnostics.

Flaviviruses are important human pathogens worldwide. Diagnostic testing for these viruses is difficult because many of the pathogens require specialized biocontainment. To address this issue, we generated 39 virus-like particle (VLP)- and nonstructural protein 1 (NS1)-secreting stable cell lines in HEK-293 cells of 13 different flaviviruses, including dengue, yellow fever, Japanese encephalitis, West Nile, St. Louis encephalitis, Zika, Rocio, Ilheus, Usutu, and Powassan viruses. Antigen secretion was stable for at least 10 cell passages, as measured by enzyme-linked immunosorbent assays and immunofluorescence assays. Thirty-five cell lines (90%) had stable antigen expression over 10 passages, with three of these cell lines (7%) increasing in antigen expression and one cell line (3%) decreasing in antigen expression. Antigen secretion in the HEK-293 cell lines was higher than in previously developed COS-1 cell line counterparts. These antigens can replace current antigens derived from live or inactivated virus for safer use in diagnostic testing. IMPORTANCE Serological diagnostic testing for flaviviral infections is hindered by the need for specialized biocontainment for preparation of reagents and assay implementation. The use of previously developed COS-1 cell lines secreting noninfectious recombinant viral antigen is limited due to diminished antigen secretion over time. Here, we describe the generation of 39 flaviviral virus-like particle (VLP)- and nonstructural protein 1 (NS1)-secreting stable cell lines in HEK-293 cells representing 13 medically important flaviviruses. Antigen production was more stable and statistically higher in these newly developed cell lines than in their COS-1 cell line counterparts. The use of these cell lines for production of flaviviral antigens will expand serological diagnostic testing of flaviviruses worldwide.

An infection-induced oxidation site regulates legumain processing and tumor growth.

Oxidative stress is a defining feature of most cancers, including those that stem from carcinogenic infections. Reactive oxygen species can drive tumor formation, yet the molecular oxidation events that contribute to tumorigenesis are largely unknown. Here we show that inactivation of a single, redox-sensitive cysteine in the host protease legumain, which is oxidized during infection with the gastric cancer-causing bacterium Helicobacter pylori, accelerates tumor growth. By using chemical proteomics to map cysteine reactivity in human gastric cells, we determined that H. pylori infection induces oxidation of legumain at Cys219. Legumain oxidation dysregulates intracellular legumain processing and decreases the activity of the enzyme in H. pylori-infected cells. We further show that the site-specific loss of Cys219 reactivity increases tumor growth and mortality in a xenograft model. Our findings establish a link between an infection-induced oxidation site and tumorigenesis while underscoring the importance of cysteine reactivity in tumor growth.

Tissue-specific biochemical differences between chronic wasting disease prions isolated from free-ranging white-tailed deer (Odocoileus virginianus).

Chronic wasting disease (CWD) is an invariably fatal prion disease affecting cervid species worldwide. Prions can manifest as distinct strains that can influence disease pathology and transmission. CWD is profoundly lymphotropic, and most infected cervids likely shed peripheral prions replicated in lymphoid organs. However, CWD is a neurodegenerative disease, and most research on prion strains has focused on neurogenic prions. Thus, a knowledge gap exists comparing neurogenic prions to lymphogenic prions. In this study, we compared prions from the obex and lymph nodes of naturally exposed white-tailed deer to identify potential biochemical strain differences. Here, we report biochemical evidence of strain differences between the brain and lymph node from these animals. Conformational stability assays, glycoform ratio analyses, and immunoreactivity scanning across the structured domain of the prion protein that refolds into the amyloid aggregate of the infectious prion reveal significantly more structural and glycoform variation in lymphogenic prions than neurogenic prions. Surprisingly, we observed greater biochemical differences among neurogenic prions than lymphogenic prions across individuals. We propose that the lymphoreticular system propagates a diverse array of prions from which the brain selects a more restricted pool of prions that may be quite different than those from another individual of the same species. Future work should examine the biological and zoonotic impact of these biochemical differences and examine more cervids from multiple locations to determine if these differences are conserved across species and locations.

DAT negative warm autoimmune haemolytic anaemia secondary to a mature cystic teratoma refractory to immunosuppressive therapy.

Mature cystic teratomas (MCTs) have a rare but recognised association with IgG-mediated autoimmune haemolytic anaemia (AIHA). We present the first case of an MCT associated with IgA-mediated AIHA. We discuss the diagnostic challenges of patients presenting with a direct antiglobulin test negative AIHA picture and the importance of reviewing these cases with the local transfusion laboratory. We also review the treatment options for MCT associated AIHA. In particular, we note they are typically resistant to immunosuppression and that surgical resection should be considered at an early stage. Although MCTs are a rare cause of AIHA, they can be treated easily and should be excluded in young women presenting with AIHA, especially if resistant to corticosteroids.

ASK1 Regulates Bleomycin-induced Pulmonary Fibrosis.

Pulmonary fibrosis (PF) is an abnormal remodeling of cellular composition and extracellular matrix that results in histological and functional alterations in the lungs. Apoptosis signal-regulating kinase-1 (ASK1) is a member of the mitogen-activated protein (MAP) kinase family that is activated by oxidative stress and promotes inflammation and apoptosis. Here we show that bleomycin-induced PF is reduced in Ask1 knockout mice (Ask1-/-) compared with wild-type (WT) mice, with improved survival and histological and functional parameters restored to basal levels. In WT mice, bleomycin caused activation of ASK1, p38, and extracellular signal-regulated kinase 1/2 (ERK1/2) in lung tissue, as well as changes in redox indicators (thioredoxin and heme-oxygenase-1), collagen content, and epithelial-mesenchymal transition markers (EMTs). These changes were largely restored toward untreated WT control levels in bleomycin-treated Ask1-/- mice. We further investigated whether treatment of WT mice with an ASK1 inhibitor, selonsertib (GS-4997), during the fibrotic phase would attenuate the development of PF. We found that pharmacological inhibition of ASK1 reduced activation of ASK1, p38, and ERK1/2 and promoted the restoration of redox and EMT indicators, as well as improvements in histological parameters. Our results suggest that ASK1 plays a central role in the development of bleomycin-induced PF in mice via p38 and ERK1/2 signaling. Together, these data indicate a possible therapeutic target for PF that involves an ASK1/p38/ERK1/2 axis.

A comparison of automated atrophy measures across the frontotemporal dementia spectrum: Implications for trials.

BACKGROUND: Frontotemporal dementia (FTD) is a common cause of young onset dementia, and whilst there are currently no treatments, there are several promising candidates in development and early phase trials. Comprehensive investigations of neuroimaging markers of disease progression across the full spectrum of FTD disorders are lacking and urgently needed to facilitate these trials. OBJECTIVE: To investigate the comparative performance of multiple automated segmentation and registration pipelines used to quantify longitudinal whole-brain atrophy across the clinical, genetic and pathological subgroups of FTD, in order to inform upcoming trials about suitable neuroimaging-based endpoints. METHODS: Seventeen fully automated techniques for extracting whole-brain atrophy measures were applied and directly compared in a cohort of 226 participants who had undergone longitudinal structural 3D T1-weighted imaging. Clinical diagnoses were behavioural variant FTD (n = 56) and primary progressive aphasia (PPA, n = 104), comprising semantic variant PPA (n = 38), non-fluent variant PPA (n = 42), logopenic variant PPA (n = 18), and PPA-not otherwise specified (n = 6). 49 of these patients had either a known pathogenic mutation or postmortem confirmation of their underlying pathology. 66 healthy controls were included for comparison. Sample size estimates to detect a 30% reduction in atrophy (80% power; 0.05 significance) were computed to explore the relative feasibility of these brain measures as surrogate markers of disease progression and their ability to detect putative disease-modifying treatment effects. RESULTS: Multiple automated techniques showed great promise, detecting significantly increased rates of whole-brain atrophy (p<0.001) and requiring sample sizes of substantially less than 100 patients per treatment arm. Across the different FTD subgroups, direct measures of volume change consistently outperformed their indirect counterparts, irrespective of the initial segmentation quality. Significant differences in performance were found between both techniques and patient subgroups, highlighting the importance of informed biomarker choice based on the patient population of interest. CONCLUSION: This work expands current knowledge and builds on the limited longitudinal investigations currently available in FTD, as well as providing valuable information about the potential of fully automated neuroimaging biomarkers for sporadic and genetic FTD trials.

SARS-CoV-2 Spike Protein Regulation of Angiotensin Converting Enzyme 2 and Tissue Renin-Angiotensin Systems: Influence of Biologic Sex.

Angiotensin converting enzyme 2 (ACE2) is an enzyme that limits activity of the renin-angiotensin system (RAS) and also serves as a receptor for the SARS-CoV-2 Spike (S) protein. Binding of S protein to ACE2 causes internalization which activates local RAS. ACE2 is on the X chromosome and its expression is regulated by sex hormones. In this study, we defined ACE2 mRNA abundance and examined effects of S protein on ACE2 activity and/or angiotensin II (AngII) levels in pivotal tissues (lung, adipose) from male and female mice. In lung, ACE2 mRNA abundance was reduced following gonadectomy (GDX) of male and female mice and was higher in XX than XY mice of the Four Core Genotypes (FCG). Reductions in lung ACE2 mRNA abundance by GDX occurred in XX, but not XY FCG female mice. Lung mRNA abundance of ADAM17 and TMPRSS2, enzymes that shed cell surface ACE2 and facilitate viral cell entry, was reduced by GDX in male but not female mice. For comparison, adipose ACE2 mRNA abundance was higher in female than male mice and higher in XX than XY FCG mice. Adipose ADAM17 mRNA abundance was increased by GDX of male and female mice. S protein reduced ACE2 activity in alveolar type II epithelial cells and 3T3-L1 adipocytes. Administration of S protein to male and female mice increased lung AngII levels and decreased adipose ACE2 activity in male but not female mice. These results demonstrate that sex differences in ACE2 expression levels may impact local RAS following S protein exposures.

Serum levels of small HDL particles are negatively correlated with death or lung transplantation in an observational study of idiopathic pulmonary fibrosis.

BACKGROUND: Serum lipoproteins, such as high-density lipoproteins (HDL), may influence disease severity in idiopathic pulmonary fibrosis (IPF). Here, we investigated associations between serum lipids and lipoproteins and clinical end-points in IPF. METHODS: Clinical data and serum lipids were analysed from a discovery cohort (59 IPF subjects, 56 healthy volunteers) and validated using an independent, multicentre cohort (207 IPF subjects) from the Pulmonary Fibrosis Foundation registry. Associations between lipids and clinical end-points (forced vital capacity, 6-min walk distance, gender age physiology (GAP) index, death or lung transplantation) were examined using Pearson's correlation and multivariable analyses. RESULTS: Serum concentrations of small HDL particles measured using nuclear magnetic resonance spectroscopy (S-HDLPNMR) correlated negatively with the GAP index in the discovery cohort of IPF subjects. The negative correlation of S-HDLPNMR with GAP index was confirmed in the validation cohort of IPF subjects. Higher levels of S-HDLPNMR were associated with lower odds of death or its competing outcome, lung transplantation (OR 0.9 for each 1-µmol·L-1 increase in S-HDLPNMR, p<0.05), at 1, 2 and 3 years from study entry in a combined cohort of all IPF subjects. CONCLUSIONS: Higher serum levels of S-HDLPNMR are negatively correlated with the GAP index, as well as with lower observed mortality or lung transplantation in IPF subjects. These findings support the hypothesis that S-HDLPNMR may modify mortality risk in patients with IPF.

Effects of a modified muscle sparing posterior technique in hip hemiarthroplasty for displaced intracapsular fractures on postoperative function compared to a standard lateral approach (HemiSPAIRE): protocol for a randomised controlled trial.

INTRODUCTION: Currently National Institute for Health and Care Excellence clinical guidelines in the UK suggest that surgeons performing partial hip replacements (hemiarthroplasty) should consider using the lateral approach. Alternatively, a newer, modified posterior approach using a muscle sparing technique named 'Save Piriformis and Internus, Repairing Externus' (SPAIRE) can be used leaving the major muscles intact. This randomised controlled trial (RCT) aims to compare the SPAIRE approach to the standard lateral approach, to determine if it allows patients to mobilise better and experience improved function after surgery. METHODS AND ANALYSIS: HemiSPAIRE is a two-arm, assessor-blinded, definitive pragmatic RCT with nested pilot and qualitative studies. Two hundred and twenty-eight participants with displaced intracapsular fractures requiring hip hemiarthroplasty will be individually randomised 1:1 to either the SPAIRE, or control (standard lateral approach) surgical procedure. Outcomes will be assessed at postoperative day 3 (POD3) and 120 (POD120). The primary outcome measure will be level of function and mobility using the Oxford Hip Score at POD120. Secondary outcomes include: De Morton Mobility Index (DEMMI), Cumulated Ambulatory Score and Numeric Pain Rating Scale (NPRS) at POD3; DEMMI, NPRS and EQ-5D-5L at POD120, complications, acute and total length of hospital stay, and mortality. Primary analysis will be on an intention-to-treat basis. Participant experiences of the impact of surgery and recovery period will be examined via up to 20 semi-structured telephone interviews. ETHICS AND DISSEMINATION: The protocol has been approved by Yorkshire and the Humber-Bradford Leeds Research Ethics Committee. Recruitment commenced in November 2019. Findings will be disseminated via research articles in peer-reviewed journals, presentations at conferences, public involvement events, patient groups and media releases. A summary of the trial findings will be shared with participants at the end of the study. TRIAL REGISTRATION NUMBER: NCT04095611.

Investigating the relationship between BMI across adulthood and late life brain pathologies.

BACKGROUND: In view of reported associations between high adiposity, particularly in midlife and late-life dementia risk, we aimed to determine associations between body mass index (BMI), and BMI changes across adulthood and brain structure and pathology at age 69-71 years. METHODS: Four hundred sixty-five dementia-free participants from Insight 46, a sub-study of the British 1946 birth cohort, who had cross-sectional T1/FLAIR volumetric MRI, and florbetapir amyloid-PET imaging at age 69-71 years, were included in analyses. We quantified white matter hyperintensity volume (WMHV) using T1 and FLAIR 3D-MRI; ß-amyloid (Aß) positivity/negativity using a SUVR approach; and whole brain (WBV) and hippocampal volumes (HV) using 3D T1-MRI. We investigated the influence of BMI, and BMI changes at and between 36, 43, 53, 60-64, 69 and 71 years, on late-life WMHV, Aß-status, WBV and mean HV. Analyses were repeated using overweight and obese status. RESULTS: At no time-point was BMI, change in BMI or overweight/obese status associated with WMHV or WBV at age 69-71 years. Decreasing BMI in the 1-2 years before imaging was associated with an increased odds of being ß-amyloid positive (OR 1.45, 95% confidence interval 1.09, 1.92). There were associations between being overweight and larger mean HV at ages 60-64 (ß = 0.073 ml, 95% CI 0.009, 0.137), 69 (ß = 0.076 ml, 95% CI 0.012, 0.140) and 71 years (ß = 0.101 ml, 95% CI 0.037, 0.165). A similar, albeit weaker, trend was seen with obese status. CONCLUSIONS: Using WMHV, ß-amyloid status and brain volumes as indicators of brain health, we do not find evidence to explain reported associations between midlife obesity and late-life dementia risk. Declining BMI in later life may reflect preclinical Alzheimer's disease.

Automated quantitative MRI volumetry reports support diagnostic interpretation in dementia: a multi-rater, clinical accuracy study.

OBJECTIVES: We examined whether providing a quantitative report (QReport) of regional brain volumes improves radiologists' accuracy and confidence in detecting volume loss, and in differentiating Alzheimer's disease (AD) and frontotemporal dementia (FTD), compared with visual assessment alone. METHODS: Our forced-choice multi-rater clinical accuracy study used MRI from 16 AD patients, 14 FTD patients, and 15 healthy controls; age range 52-81. Our QReport was presented to raters with regional grey matter volumes plotted as percentiles against data from a normative population (n = 461). Nine raters with varying radiological experience (3 each: consultants, registrars, 'non-clinical image analysts') assessed each case twice (with and without the QReport). Raters were blinded to clinical and demographic information; they classified scans as 'normal' or 'abnormal' and if 'abnormal' as 'AD' or 'FTD'. RESULTS: The QReport improved sensitivity for detecting volume loss and AD across all raters combined (p = 0.015* and p = 0.002*, respectively). Only the consultant group's accuracy increased significantly when using the QReport (p = 0.02*). Overall, raters' agreement (Cohen's κ) with the 'gold standard' was not significantly affected by the QReport; only the consultant group improved significantly (κs 0.41➔0.55, p = 0.04*). Cronbach's alpha for interrater agreement improved from 0.886 to 0.925, corresponding to an improvement from 'good' to 'excellent'. CONCLUSION: Our QReport referencing single-subject results to normative data alongside visual assessment improved sensitivity, accuracy, and interrater agreement for detecting volume loss. The QReport was most effective in the consultants, suggesting that experience is needed to fully benefit from the additional information provided by quantitative analyses. KEY POINTS: • The use of quantitative report alongside routine visual MRI assessment improves sensitivity and accuracy for detecting volume loss and AD vs visual assessment alone. • Consultant neuroradiologists' assessment accuracy and agreement (kappa scores) significantly improved with the use of quantitative atrophy reports. • First multi-rater radiological clinical evaluation of visual quantitative MRI atrophy report for use as a diagnostic aid in dementia.