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1.
Age Ageing ; 53(5)2024 May 01.
Article in English | MEDLINE | ID: mdl-38706391

ABSTRACT

INTRODUCTION: Sporadic Creutzfeldt-Jakob disease (sCJD) is a rapidly progressive neurodegenerative disease with public health implications. Mean age of onset is 68 years. Age-specific incidence declines after 80 years. This may arise from under-ascertainment or other biological features of the disease. Accurate characterisation of late-onset sCJD is important for early diagnosis, avoiding unnecessary investigations and improving ascertainment for public health purposes. OBJECTIVE: To phenotype the clinical features and investigation profile of sCJD in adults >80 years. METHODS: We analysed all probable and definite sCJD cases identified by the UK National CJD Research & Surveillance Unit over a 10-year period (2011-2021). Individuals were grouped by age of onset. Clinical features and investigation profiles were compared. RESULTS: 10.3% (123/1196) had an age of onset over 80. Median survival was shorter (3.2 vs 4.3 months; P < 0.001). Pyramidal signs (48.3% vs 34.2%; P = 0.008) and akinetic mutism (55.1% vs 33.2%; P < 0.001) were more frequent. Psychiatric symptoms (26.3% vs 39.6%; P = 0.01) and cerebellar signs (65.4% vs 78.6%, P = 0.007) were less frequent. Cognitive impairment and myoclonus were highly prevalent regardless of age. Between age groups, the diagnostic sensitivity of cerebrospinal fluid real-time quaking-induced conversion (CSF RT-QuIC) (92.9% vs 91.9%, P = 0.74) was comparable, electroencephalography was superior (41.5% vs 25.4%; P = 0.006) and MRI was inferior (67.8% vs 91.4%; P < 0.001). CONCLUSIONS: Late-onset sCJD has distinct clinical features, shorter survival and a different profile of investigation sensitivity. CSF RT-QuIC, MRI brain and specialist CJD review is recommended in older adults with a rapidly progressive neurological disorder. Autopsy is valuable when the cause remains elusive.


Subject(s)
Age of Onset , Creutzfeldt-Jakob Syndrome , Humans , Creutzfeldt-Jakob Syndrome/epidemiology , Creutzfeldt-Jakob Syndrome/diagnosis , Creutzfeldt-Jakob Syndrome/mortality , United Kingdom/epidemiology , Male , Female , Aged, 80 and over , Incidence , Phenotype , Magnetic Resonance Imaging , Electroencephalography
2.
SLAS Technol ; : 100143, 2024 May 11.
Article in English | MEDLINE | ID: mdl-38740284

ABSTRACT

Within a growing drug discovery company, scientists acquire (either through in house synthesis or purchase) then store, retrieve, and ship solid compound samples daily between multiple locations. The efficient management and tracking of this entire process to support drug discovery is a significant challenge. This article describes a decentralized and cost-effective inventory facility that simplifies the solid compound storage and retrieval process. Standardized storage cabinets from the market are utilized, providing a cost-effective physical infrastructure. The cabinets can be distributed across storage rooms at multiple sites and arranged into spaces with a variety of dimensions, allowing the system to be retrofitted into existing facilities and scaled up easily. We can provide storage close to work areas at each location, minimizing both unnecessary movement of staff and transportation of substances. We have applied a systematic barcoding method to the compound batch identifier that correlates with its compound location. This simplifies the compound registration process as well as the process of finding and returning compounds. Additionally, a centralized electronic platform has been employed to store, update and track solid compound information, such as properties, location and quantity. Compound shipment may be initiated from different sites, and a centralized electronic platform assists the information retrieval process, ensuring each location possesses up-to-date information. The electronic platform we present streamlines the management of compound registration, location tracking, weight updates and shipment information, facilitating seamless record sharing among all stakeholders. Every step of the process can be tracked in real time by the project team. The platform can be flexibly configured to adapt to an evolving set of storage locations, with all information and processes being audited.

3.
Protein Sci ; 33(6): e4991, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38757381

ABSTRACT

The de novo design of miniprotein inhibitors has recently emerged as a new technology to create proteins that bind with high affinity to specific therapeutic targets. Their size, ease of expression, and apparent high stability makes them excellent candidates for a new class of protein drugs. However, beyond circular dichroism melts and hydrogen/deuterium exchange experiments, little is known about their dynamics, especially at the elevated temperatures they seemingly tolerate quite well. To address that and gain insight for future designs, we have focused on identifying unintended and previously overlooked heat-induced structural and chemical changes in a particularly stable model miniprotein, EHEE_rd2_0005. Nuclear magnetic resonance (NMR) studies suggest the presence of dynamics on multiple time and temperature scales. Transiently elevating the temperature results in spontaneous chemical deamidation visible in the NMR spectra, which we validate using both capillary electrophoresis and mass spectrometry (MS) experiments. High temperatures also result in greatly accelerated intrinsic rates of hydrogen exchange and signal loss in NMR heteronuclear single quantum coherence spectra from local unfolding. These losses are in excellent agreement with both room temperature hydrogen exchange experiments and hydrogen bond disruption in replica exchange molecular dynamics simulations. Our analysis reveals important principles for future miniprotein designs and the potential for high stability to result in long-lived alternate conformational states.


Subject(s)
Hot Temperature , Nuclear Magnetic Resonance, Biomolecular , Molecular Dynamics Simulation , Protein Conformation , Proteins/chemistry , Protein Stability
4.
J Neurol ; 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38597944

ABSTRACT

INTRODUCTION: Incorporation of the real-time quaking-induced conversion (RT-QuIC) assays for diagnosis of sporadic Creutzfeldt-Jakob disease (CJD) has transformed diagnosis largely related to its extremely high specificity. However, the test has a c.10% false-negative result and we aim to characterize the clinical features, investigation profile, and molecular subtype in this cohort of patients. METHODS: 250 individuals diagnosed with definite sporadic CJD were identified from the UK National CJD Research and Surveillance Unit from 2012 to 2023. We compared the clinical features and investigation profile in those with a negative CSF RT-QuIC to those with a positive RT-QuIC. RESULTS: 27 individuals (10.8%) were CSF RT-QuIC negative. Median age of onset was younger (62 years vs 68 years, p = 0.002), median disease duration was longer (4.4 months vs 10.5 months, p < 0.001), and these individuals were less likely to present with gait difficulties (73% vs 93%, p = 0.003) or motor symptoms (62% vs 80%, p = 0.04). The sensitivity of electroencephalography and diffusion-weighted MRI were similar in both groups. In those who were RT-QuIC negative, there was an overrepresentation of the VV1 (32% vs 1%) and MM2 molecular subtypes (21% vs 3%). Co-occurring neurodegenerative disease was found in 33% (9/27) of those who were RT-QuIC negative. CONCLUSIONS: Individuals with sporadic CJD and a negative CSF RT-QuIC present with younger age of onset, different clinical features and are over-represented with the VV1 and MM2 subtypes of sporadic CJD. Further work is required to better understand the biochemical properties contributing to RT-QuIC negative results in these cases.

5.
medRxiv ; 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38645146

ABSTRACT

Mutations in the MAPT gene encoding tau protein can cause autosomal dominant neurodegenerative tauopathies including frontotemporal dementia (often with Parkinsonism). In Alzheimer's disease, the most common tauopathy, synapse loss is the strongest pathological correlate of cognitive decline. Recently, PET imaging with synaptic tracers revealed clinically relevant loss of synapses in primary tauopathies; however, the molecular mechanisms leading to synapse degeneration in primary tauopathies remain largely unknown. In this study, we examined post-mortem brain tissue from people who died with frontotemporal dementia with tau pathology (FTDtau) caused by the MAPT intronic exon 10+16 mutation, which increases splice variants containing exon 10 resulting in higher levels of tau with four microtubule binding domains. We used RNA sequencing and histopathology to examine temporal cortex and visual cortex, to look for molecular phenotypes compared to age, sex, and RNA integrity matched participants who died without neurological disease (n=12 per group). Bulk tissue RNA sequencing reveals substantial downregulation of gene expression associated with synaptic function. Upregulated biological pathways in human MAPT 10+16 brain included those involved in transcriptional regulation, DNA damage response, and neuroinflammation. Histopathology confirmed increased pathological tau accumulation in FTDtau cortex as well as a loss of presynaptic protein staining, and region-specific increased colocalization of phospho-tau with synapses in temporal cortex. Our data indicate that synaptic pathology likely contributes to pathogenesis in FTDtau caused by the MAPT 10+16 mutation.

6.
Front Bioeng Biotechnol ; 12: 1352794, 2024.
Article in English | MEDLINE | ID: mdl-38686117

ABSTRACT

As a solution to restore knee function and reduce pain, the demand for Total Knee Arthroplasty (TKA) has dramatically increased in recent decades. The high rates of dissatisfaction and revision makes it crucially important to understand the relationships between surgical factors and post-surgery knee performance. Tibial implant alignment in the sagittal plane (i.e., posterior tibia slope, PTS) is thought to play a key role in quadriceps muscle forces and contact conditions of the joint, but the underlying mechanisms and potential consequences are poorly understood. To address this biomechanical challenge, we developed a subject-specific musculoskeletal model based on the bone anatomy and precise implantation data provided within the CAMS-Knee datasets. Using the novel COMAK algorithm that concurrently optimizes joint kinematics, together with contact mechanics, and muscle and ligament forces, enabled highly accurate estimations of the knee joint biomechanics (RMSE <0.16 BW of joint contact force) throughout level walking and squatting. Once confirmed for accuracy, this baseline modelling framework was then used to systematically explore the influence of PTS on knee joint biomechanics. Our results indicate that PTS can greatly influence tibio-femoral translations (mainly in the anterior-posterior direction), while also suggesting an elevated risk of patellar mal-tracking and instability. Importantly, however, an increased PTS was found to reduce the maximum tibio-femoral contact force and improve efficiency of the quadriceps muscles, while also reducing the patellofemoral contact force (by approximately 1.5% for each additional degree of PTS during walking). This study presents valuable findings regarding the impact of PTS variations on the biomechanics of the TKA joint and thereby provides potential guidance for surgically optimizing implant alignment in the sagittal plane, tailored to the implant design and the individual deficits of each patient.

7.
J Struct Biol ; 216(2): 108082, 2024 Mar 02.
Article in English | MEDLINE | ID: mdl-38438058

ABSTRACT

While protein activity is traditionally studied with a major focus on the active site, the activity of enzymes has been hypothesized to be linked to the flexibility of adjacent regions, warranting more exploration into how the dynamics in these regions affects catalytic turnover. One such enzyme is Xylanase A (XylA), which cleaves hemicellulose xylan polymers by hydrolysis at internal ß-1,4-xylosidic linkages. It contains a "thumb" region whose flexibility has been suggested to affect the activity. The double mutation D11F/R122D was previously found to affect activity and potentially bias the thumb region to a more open conformation. We find that the D11F/R122D double mutation shows substrate-dependent effects, increasing activity on the non-native substrate ONPX2 but decreasing activity on its native xylan substrate. To characterize how the double mutant causes these kinetics changes, nuclear magnetic resonance (NMR) and molecular dynamics (MD) simulations were used to probe structural and flexibility changes. NMR chemical shift perturbations revealed structural changes in the double mutant relative to the wild-type, specifically in the thumb and fingers regions. Increased slow-timescale dynamics in the fingers region was observed as intermediate-exchange line broadening. Lipari-Szabo order parameters show negligible changes in flexibility in the thumb region in the presence of the double mutation. To help understand if there is increased energetic accessibility to the open state upon mutation, alchemical free energy simulations were employed that indicated thumb opening is more favorable in the double mutant. These studies aid in further characterizing how flexibility in adjacent regions affects the function of XylA.

8.
Neurol Clin Pract ; 14(3): e200271, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38525067

ABSTRACT

Background and Objectives: Sporadic cerebral small vessel disease (CSVD) is a class of important pathologic processes known to affect the aging brain and to contribute to cognitive impairment. We aimed to identify clinical risk factors associated with postmortem CSVD in middle-aged to older adults. Methods: We developed and tested risk models for their predictive accuracy of a pathologic diagnosis of nonamyloid CSVD and cerebral amyloid angiopathy (CAA) in a retrospective sample of 160 autopsied cases from the Edinburgh Brain Bank. Individuals aged 40 years and older covering the spectrum of healthy aging and common forms of dementia (i.e., highly-prevalent etiologies such as Alzheimer disease (AD), vascular cognitive impairment (VCI), and mixed dementia) were included. We performed binomial logistic regression models using sample splitting and cross-validation methods. Demographics, lifestyle habits, traditional vascular risk factors, chronic medical conditions, APOE4, and cognitive status were assessed as potential predictors. Results: Forty percent of our sample had a clinical diagnosis of dementia (AD = 33, VCI = 26 and mixed = 5) while others were cognitively healthy (n = 96). The mean age at death was 73.8 (SD 14.1) years, and 40% were female. The presence of none-to-mild vs moderate-to-severe nonamyloid CSVD was predicted by our model with good accuracy (area under the curve [AUC] = 0.84, sensitivity [SEN] = 72%, specificity [SPE] = 95%), with the most significant clinical predictors being age, history of cerebrovascular events, and cognitive impairment. The presence of CAA pathology was also predicted with high accuracy (AUC = 0.86, SEN = 93%, SPE = 79%). Significant predictors included alcohol intake, history of cerebrovascular events, and cognitive impairment. In a subset of atypical dementias (n = 24), our models provided poor predictive performance for both nonamyloid CSVD (AUC = 0.50) and CAA (AUC = 0.43). Discussion: CSVD pathology can be predicted with high accuracy based on clinical factors in patients within the spectrum of AD, VCI, and normal aging. Whether this prediction can be enhanced by the addition of fluid and neuroimaging biomarkers warrants additional study. Improving our understanding of clinical determinants of vascular brain health may lead to novel strategies in the prevention and treatment of vascular etiologies contributing to cognitive decline. Classification of Evidence: This study provides Class II evidence that selected clinical factors accurately distinguish between middle-aged to older adults with and without cerebrovascular small vessel disease (amyloid and nonamyloid) pathology.

9.
Behav Sci Law ; 42(2): 96-114, 2024.
Article in English | MEDLINE | ID: mdl-38341766

ABSTRACT

Violent rhetoric online is becoming increasingly relevant to the practice of forensic mental health assessment as examinee's virtual lives may transform into real-world acts of violence. With the rise of a diverse subculture of violent online communities, the aim of the present study was to inform how concerns with online sources of collateral data and racial/ethnic biases may influence determinations of violence potential. Using an experimental design, jury-eligible participants (N = 278) and forensic mental health experts (N = 78) were presented with mock Twitter (now referred to as X) posts that varied by data source (i.e., how information was accessed) and the examinee's race/ethnicity. Results showed no differences in participants' ratings of data credibility, how much weight they would place on the posts in a threat assessment, or how likely the examinee was to act violently against his intended target. Implications regarding the interpretation of social media evidence, relevant limitations, and future research are discussed.


Subject(s)
Ethnicity , Social Media , Humans , Mental Health , Internet
10.
JAMA Netw Open ; 7(2): e240098, 2024 Feb 05.
Article in English | MEDLINE | ID: mdl-38381433

ABSTRACT

Importance: Black patients are more likely than White patients to be restrained during behavioral crises in emergency departments (EDs). Although the perils of policing mental health for Black individuals are recognized, it is unclear whether or to what extent police transport mediates the association between Black race and use of physical restraint in EDs. Objective: To evaluate the degree to which police transport mediates the association between Black race and use of physical restraint in EDs. Design, Setting, and Participants: This retrospective, cross-sectional study used electronic health record data from ED visits by adults (aged ≥18 years) to 3 hospitals in the southeastern US and 10 in the northeastern US between January 1, 2015, and December 31, 2022. Data were analyzed from September 1, 2022, to May 30, 2023. Exposures: Race, ethnicity, and police transport to the hospital. Main Outcomes and Measures: The primary outcome variable was the presence of an order for restraints during an ED visit. Results: A total of 4 263 437 ED visits by 1 257 339 patients (55.5% of visits by female and 44.5% by male patients; 26.1% by patients 65 years or older) were included in the study. Black patients accounted for 27.5% of visits; Hispanic patients, 17.6%; White patients, 50.3%; and other or unknown race or ethnicity, 4.6%. In models adjusted for age, sex, site, previous behavioral or psychiatric history, and visit diagnoses, Black patients were at increased odds of experiencing restraint compared with White patients (adjusted odds ratio [AOR], 1.33 [95% CI, 1.28-1.37]). Within the mediation analysis, Black patients had higher odds of being brought to the hospital by police compared with all other patients (AOR, 1.38 [95% CI, 1.34-1.42]). Patients brought to the ED under police transport had increased odds of experiencing restraint compared with all other modes of transport (AOR, 5.51 [95% CI, 5.21-5.82]). The estimated proportion of use of restraints for Black patients mediated by police transport was 10.70% (95% CI, 9.26%-12.53%). Conclusions and Relevance: In this cross-sectional study of ED visits across 13 hospitals, police transport may have mediated the association between Black race and use of physical restraint. These findings suggest a need to further explore the mechanisms by which transport to emergency care may influence disparate restrictive interventions for patients experiencing behavioral emergencies.


Subject(s)
Police , Restraint, Physical , Adult , Humans , Female , Male , Adolescent , Cross-Sectional Studies , Retrospective Studies , Emergency Service, Hospital
11.
J Imaging Inform Med ; 37(1): 92-106, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38343238

ABSTRACT

A critical clinical indicator for basal cell carcinoma (BCC) is the presence of telangiectasia (narrow, arborizing blood vessels) within the skin lesions. Many skin cancer imaging processes today exploit deep learning (DL) models for diagnosis, segmentation of features, and feature analysis. To extend automated diagnosis, recent computational intelligence research has also explored the field of Topological Data Analysis (TDA), a branch of mathematics that uses topology to extract meaningful information from highly complex data. This study combines TDA and DL with ensemble learning to create a hybrid TDA-DL BCC diagnostic model. Persistence homology (a TDA technique) is implemented to extract topological features from automatically segmented telangiectasia as well as skin lesions, and DL features are generated by fine-tuning a pre-trained EfficientNet-B5 model. The final hybrid TDA-DL model achieves state-of-the-art accuracy of 97.4% and an AUC of 0.995 on a holdout test of 395 skin lesions for BCC diagnosis. This study demonstrates that telangiectasia features improve BCC diagnosis, and TDA techniques hold the potential to improve DL performance.

12.
J Imaging Inform Med ; 2024 Feb 08.
Article in English | MEDLINE | ID: mdl-38332404

ABSTRACT

In recent years, deep learning (DL) has been used extensively and successfully to diagnose different cancers in dermoscopic images. However, most approaches lack clinical inputs supported by dermatologists that could aid in higher accuracy and explainability. To dermatologists, the presence of telangiectasia, or narrow blood vessels that typically appear serpiginous or arborizing, is a critical indicator of basal cell carcinoma (BCC). Exploiting the feature information present in telangiectasia through a combination of DL-based techniques could create a pathway for both, improving DL results as well as aiding dermatologists in BCC diagnosis. This study demonstrates a novel "fusion" technique for BCC vs non-BCC classification using ensemble learning on a combination of (a) handcrafted features from semantically segmented telangiectasia (U-Net-based) and (b) deep learning features generated from whole lesion images (EfficientNet-B5-based). This fusion method achieves a binary classification accuracy of 97.2%, with a 1.3% improvement over the corresponding DL-only model, on a holdout test set of 395 images. An increase of 3.7% in sensitivity, 1.5% in specificity, and 1.5% in precision along with an AUC of 0.99 was also achieved. Metric improvements were demonstrated in three stages: (1) the addition of handcrafted telangiectasia features to deep learning features, (2) including areas near telangiectasia (surround areas), (3) discarding the noisy lower-importance features through feature importance. Another novel approach to feature finding with weak annotations through the examination of the surrounding areas of telangiectasia is offered in this study. The experimental results show state-of-the-art accuracy and precision in the diagnosis of BCC, compared to three benchmark techniques. Further exploration of deep learning techniques for individual dermoscopy feature detection is warranted.

13.
Acta Neuropathol ; 147(1): 32, 2024 Feb 06.
Article in English | MEDLINE | ID: mdl-38319380

ABSTRACT

Synapse loss correlates with cognitive decline in Alzheimer's disease, and soluble oligomeric amyloid beta (Aß) is implicated in synaptic dysfunction and loss. An important knowledge gap is the lack of understanding of how Aß leads to synapse degeneration. In particular, there has been difficulty in determining whether there is a synaptic receptor that binds Aß and mediates toxicity. While many candidates have been observed in model systems, their relevance to human AD brain remains unknown. This is in part due to methodological limitations preventing visualization of Aß binding at individual synapses. To overcome this limitation, we combined two high resolution microscopy techniques: array tomography and Förster resonance energy transfer (FRET) to image over 1 million individual synaptic terminals in temporal cortex from AD (n = 11) and control cases (n = 9). Within presynapses and post-synaptic densities, oligomeric Aß generates a FRET signal with transmembrane protein 97. Further, Aß generates a FRET signal with cellular prion protein, and post-synaptic density 95 within post synapses. Transmembrane protein 97 is also present in a higher proportion of post synapses in Alzheimer's brain compared to controls. We inhibited Aß/transmembrane protein 97 interaction in a mouse model of amyloidopathy by treating with the allosteric modulator CT1812. CT1812 drug concentration correlated negatively with synaptic FRET signal between transmembrane protein 97 and Aß. In human-induced pluripotent stem cell derived neurons, transmembrane protein 97 is present in synapses and colocalizes with Aß when neurons are challenged with human Alzheimer's brain homogenate. Transcriptional changes are induced by Aß including changes in genes involved in neurodegeneration and neuroinflammation. CT1812 treatment of these neurons caused changes in gene sets involved in synaptic function. These data support a role for transmembrane protein 97 in the synaptic binding of Aß in human Alzheimer's disease brain where it may mediate synaptotoxicity.


Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Membrane Proteins , Animals , Humans , Mice , Amyloid beta-Peptides , Brain , Synapses , Membrane Proteins/metabolism
14.
BMC Geriatr ; 24(1): 12, 2024 01 03.
Article in English | MEDLINE | ID: mdl-38172703

ABSTRACT

BACKGROUND: Variant Creutzfeldt - Jakob disease (vCJD) arose from dietary contamination with bovine-spongiform-encephalopathy (BSE). Because of concerns that vCJD-cases might be missed in the elderly, a feasibility study of enhanced CJD surveillance on the elderly was begun in 2016. Recruitment was lower than predicted. We describe a review of the challenges encountered in that study: identification, referral, and recruitment, and the effects of actions based on the results of that review. METHODS: Review was conducted in 2017. Study data for all eligible cases identified and referred from one participating service (Anne Rowling clinic (ARC)) was curated and anonymised in a bespoke database. A questionnaire was sent out to all the clinicians in medicine of the elderly, psychiatry of old age and neurology (including ARC) specialties in NHS Lothian, exploring possible reasons for low recruitment. RESULTS: Sixty-eight cases were referred from the ARC (March 2016-September 2017): 25% were recruited. Most cases had been referred because of diagnostic uncertainty. No difference was seen between those recruited and the non-recruited, apart from age and referrer. Twelve of 60 participating clinicians completed the questionnaire: only 4 had identified eligible cases. High workload, time constraints, forgetting to refer, unfamiliarity with the eligibility criteria, and the rarity of eligible cases, were some of the reasons given. Suggestions as to how to improve referral of eligible cases included: regular email reminders, feedback to referrers, improving awareness of the study, visible presence of the study team, and integration of the study with other research oriented services. These results were used to increase recruitment but without success. CONCLUSION: Recruitment was lower than predicted. Actions taken following a review at 21 months did not lead to significant improvement; recruitment remained low, with many families/patients declining to take part (75%). In assessing the failure to improve recruitment, two factors need to be considered. Firstly, the initial referral rate was expected to be higher because of existing patients already known to the clinical services, with later referrals being only newly presenting patients. Secondly, the unplanned absence of a dedicated study nurse. Searching digital records/anonymised derivatives to identify eligible patients could be explored.


Subject(s)
Creutzfeldt-Jakob Syndrome , Humans , Animals , Cattle , Aged , Feasibility Studies , Creutzfeldt-Jakob Syndrome/diagnosis , Creutzfeldt-Jakob Syndrome/epidemiology , Scotland
15.
Acta Neuropathol ; 147(1): 7, 2024 Jan 04.
Article in English | MEDLINE | ID: mdl-38175261

ABSTRACT

Tau hyperphosphorylation and aggregation is a common feature of many dementia-causing neurodegenerative diseases. Tau can be phosphorylated at up to 85 different sites, and there is increasing interest in whether tau phosphorylation at specific epitopes, by specific kinases, plays an important role in disease progression. The AMP-activated protein kinase (AMPK)-related enzyme NUAK1 has been identified as a potential mediator of tau pathology, whereby NUAK1-mediated phosphorylation of tau at Ser356 prevents the degradation of tau by the proteasome, further exacerbating tau hyperphosphorylation and accumulation. This study provides a detailed characterisation of the association of p-tau Ser356 with progression of Alzheimer's disease pathology, identifying a Braak stage-dependent increase in p-tau Ser356 protein levels and an almost ubiquitous presence in neurofibrillary tangles. We also demonstrate, using sub-diffraction-limit resolution array tomography imaging, that p-tau Ser356 co-localises with synapses in AD postmortem brain tissue, increasing evidence that this form of tau may play important roles in AD progression. To assess the potential impacts of pharmacological NUAK inhibition in an ex vivo system that retains multiple cell types and brain-relevant neuronal architecture, we treated postnatal mouse organotypic brain slice cultures from wildtype or APP/PS1 littermates with the commercially available NUAK1/2 inhibitor WZ4003. Whilst there were no genotype-specific effects, we found that WZ4003 results in a culture-phase-dependent loss of total tau and p-tau Ser356, which corresponds with a reduction in neuronal and synaptic proteins. By contrast, application of WZ4003 to live human brain slice cultures results in a specific lowering of p-tau Ser356, alongside increased neuronal tubulin protein. This work identifies differential responses of postnatal mouse organotypic brain slice cultures and adult human brain slice cultures to NUAK1 inhibition that will be important to consider in future work developing tau-targeting therapeutics for human disease.


Subject(s)
Alzheimer Disease , Adult , Humans , Animals , Mice , Brain , Anilides , Neurofibrillary Tangles , Protein Kinases , Repressor Proteins
16.
Schizophr Res ; 264: 362-369, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38219412

ABSTRACT

Within the Veterans Affairs (VA), management of self-harm is a major clinical priority. However, there is limited information on risks for self-harm among VA patients with emerging psychotic disorders relative to VA patients with other emerging mental health conditions. Using information from fiscal years 2010 through 2018, a national cohort of VA patients 30 or younger was classified based on mental health diagnoses into three groups: 1) early episode psychosis (EEP), 2) non-early episode psychosis mental health (non-EEP MH), or 3) no mental health (no MH). Analyses focused on cohort members' risk for all-cause mortality, suicide mortality, and non-fatal suicide attempts (NFSA) during the year following initial diagnosis of mental health conditions (or first year of VA care, for the no MH group). In unadjusted analyses, the EEP group had elevated rates of all-cause mortality, suicide mortality, and NFSA relative to the non-EEP MH and no MH groups and the non-EEP MH had elevated rates of all-cause mortality, suicide mortality, and NFSA relative to the no MH group. After adjusting for demographics and care receipt, EEP status was unrelated to all-cause mortality but associated with increased suicide mortality risk and NFSA. Non-EEP MH status was associated with reduced risk of all-cause mortality but increased risk for NFSA. In the year following first diagnosis, VA patients with EEP are at increased risk for suicide mortality and self-harm even after accounting for other risk factors. Clinical services targeting this crucial time can help promote safety for this vulnerable group.


Subject(s)
Psychotic Disorders , Suicide , Veterans , Humans , Veterans Health , Psychotic Disorders/epidemiology , Psychotic Disorders/psychology , Suicide, Attempted , Mental Health
17.
Brain Pathol ; 34(2): e13214, 2024 03.
Article in English | MEDLINE | ID: mdl-37771100

ABSTRACT

Human prion diseases, including Creutzfeldt-Jakob disease (CJD), occur in sporadic, genetic, and acquired forms. Variant Creutzfeldt-Jakob disease (vCJD) first reported in 1996 in the United Kingdom (UK), resulted from contamination of food with bovine spongiform encephalopathy. There is a concern that UK national surveillance mechanisms might miss some CJD cases (including vCJD), particularly in the older population where other neurodegenerative disorders are more prevalent. We developed a highly sensitive protocol for analysing autopsy brain tissue for the misfolded prion protein (PrPSc ) associated with prion disease, which could be used to screen for prion disease in the elderly. Brain tissue samples from 331 donors to the Edinburgh Brain and Tissue Bank (EBTB), from 2005 to 2022, were analysed, using immunohistochemical analysis on fixed tissue, and five biochemical tests on frozen specimens from six brain regions, based on different principles for detecting PrPSc . An algorithm was established for classifying the biochemical results. To test the effectiveness of the protocol, several neuropathologically confirmed prion disease controls, including vCJD, were included and blinded in the study cohort. On unblinding, all the positive control cases had been correctly identified. No other cases tested positive; our analysis uncovered no overlooked prion disease cases. Our algorithm for classifying cases was effective for handling anomalous biochemical results. An overall analysis suggested that a reduced biochemical protocol employing only three of the five tests on only two brain tissue regions gave sufficient sensitivity and specificity. We conclude that this protocol may be useful as a UK-wide screening programme for human prion disease in selected brains from autopsies in the elderly. Further improvements to the protocol were suggested by enhancements of the in vitro conversion assays made during the course of this study.


Subject(s)
Creutzfeldt-Jakob Syndrome , Prion Diseases , Prions , Tissue and Organ Procurement , Animals , Cattle , Humans , Aged , Creutzfeldt-Jakob Syndrome/epidemiology , Prion Diseases/genetics , Brain/metabolism , Prions/metabolism
18.
Behav Res Methods ; 56(3): 2158-2193, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37450219

ABSTRACT

The Implicit Association Test (IAT), like many behavioral measures, seeks to quantify meaningful individual differences in cognitive processes that are difficult to assess with approaches like self-reports. However, much like other behavioral measures, many IATs appear to show low test-retest reliability and typical scoring methods fail to quantify all of the decision-making processes that generate the overt task performance. Here, we develop a new modeling approach for IATs based on the geometric similarity representation (GSR) model. This model leverages both response times and accuracy on IATs to make inferences about representational similarity between the stimuli and categories. The model disentangles processes related to response caution, stimulus encoding, similarities between concepts and categories, and response processes unrelated to the choice itself. This approach to analyzing IAT data illustrates that the unreliability in IATs is almost entirely attributable to the methods used to analyze data from the task: GSR model parameters show test-retest reliability around .80-.90, on par with reliable self-report measures. Furthermore, we demonstrate how model parameters result in greater validity compared to the IAT D-score, Quad model, and simple diffusion model contrasts, predicting outcomes related to intergroup contact and motivation. Finally, we present a simple point-and-click software tool for fitting the model, which uses a pre-trained neural network to estimate best-fit parameters of the GSR model. This approach allows easy and instantaneous fitting of IAT data with minimal demands on coding or technical expertise on the part of the user, making the new model accessible and effective.


Subject(s)
Motivation , Social Perception , Humans , Reproducibility of Results , Surveys and Questionnaires , Self Report
19.
Am J Prev Med ; 66(1): 154-158, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37661074

ABSTRACT

INTRODUCTION: Police involvement in patient transport to emergency medical care has increased over time, yet studies assessing racial inequities in transport are limited. This study evaluated the relationship between race and police transport to the emergency department for adult patients. METHODS: This cross-sectional study evaluated adult (aged ≥18 years) visits at 13 different emergency departments across two regional hospital systems in the Southeastern and Northeastern U.S. from 2015 to 2022. Data were extracted from electronic health records. This analysis evaluated the association between race and transport by police transport using generalized linear multivariable mixed model with a binary logistic link for presence of police transport. Data were nested by patient and adjusted for site, demographics, and diagnostic visit characteristics. RESULTS: Of 4,291,809 adult emergency department visits, 25,901 (0.6%) involved transport by police. Of the 25,901 visits in police-involved encounters, 10,513 (40.6%) patients were Black, and 9,827 (37.9%) were White. The adjusted model showed that Black patients were at higher odds of transport by police than White patients (AOR=1.64; 95% CI=1.57-1.72). Male sex, younger age (18-35 years), history of behavioral health diagnosis, and emergency department psychiatric or substance use disorders were independently associated with increased odds of police transport. CONCLUSIONS: This analysis revealed racial inequities in police-involved transport to emergency medical care, highlighting an urgent need to evaluate drivers of inequities and the ways in which police transport influences clinical outcomes.


Subject(s)
Emergency Service, Hospital , Police , Adult , Humans , Male , Adolescent , Young Adult , Cross-Sectional Studies , Patients
20.
Glia ; 72(2): 375-395, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37909242

ABSTRACT

White matter abnormalities, related to poor cerebral perfusion, are a core feature of small vessel cerebrovascular disease, and critical determinants of vascular cognitive impairment and dementia. Despite this importance there is a lack of treatment options. Proliferation of microglia producing an expanded, reactive population and associated neuroinflammatory alterations have been implicated in the onset and progression of cerebrovascular white matter disease, in patients and in animal models, suggesting that targeting microglial proliferation may exert protection. Colony-stimulating factor-1 receptor (CSF1R) is a key regulator of microglial proliferation. We found that the expression of CSF1R/Csf1r and other markers indicative of increased microglial abundance are significantly elevated in damaged white matter in human cerebrovascular disease and in a clinically relevant mouse model of chronic cerebral hypoperfusion and vascular cognitive impairment. Using the mouse model, we investigated long-term pharmacological CSF1R inhibition, via GW2580, and demonstrated that the expansion of microglial numbers in chronic hypoperfused white matter is prevented. Transcriptomic analysis of hypoperfused white matter tissue showed enrichment of microglial and inflammatory gene sets, including phagocytic genes that were the predominant expression modules modified by CSF1R inhibition. Further, CSF1R inhibition attenuated hypoperfusion-induced white matter pathology and rescued spatial learning impairments and to a lesser extent cognitive flexibility. Overall, this work suggests that inhibition of CSF1R and microglial proliferation mediates protection against chronic cerebrovascular white matter pathology and cognitive deficits. Our study nominates CSF1R as a target for the treatment of vascular cognitive disorders with broader implications for treatment of other chronic white matter diseases.


Subject(s)
Cerebrovascular Disorders , Cognition Disorders , Cognitive Dysfunction , Leukoencephalopathies , Receptors, Granulocyte-Macrophage Colony-Stimulating Factor , White Matter , Animals , Mice , Cerebrovascular Disorders/metabolism , Cerebrovascular Disorders/pathology , Cognition Disorders/etiology , Cognition Disorders/pathology , Cognitive Dysfunction/metabolism , Disease Models, Animal , Leukoencephalopathies/genetics , Leukoencephalopathies/metabolism , Mice, Inbred C57BL , Microglia/metabolism , Receptors, Colony-Stimulating Factor/metabolism , White Matter/pathology , Receptors, Granulocyte-Macrophage Colony-Stimulating Factor/antagonists & inhibitors , Receptors, Granulocyte-Macrophage Colony-Stimulating Factor/metabolism
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