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1.
Nature ; 598(7881): 510-514, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34646013

RESUMO

Human epithelial tissues accumulate cancer-driver mutations with age1-9, yet tumour formation remains rare. The positive selection of these mutations suggests that they alter the behaviour and fitness of proliferating cells10-12. Thus, normal adult tissues become a patchwork of mutant clones competing for space and survival, with the fittest clones expanding by eliminating their less competitive neighbours11-14. However, little is known about how such dynamic competition in normal epithelia influences early tumorigenesis. Here we show that the majority of newly formed oesophageal tumours are eliminated through competition with mutant clones in the adjacent normal epithelium. We followed the fate of nascent, microscopic, pre-malignant tumours in a mouse model of oesophageal carcinogenesis and found that most were rapidly lost with no indication of tumour cell death, decreased proliferation or an anti-tumour immune response. However, deep sequencing of ten-day-old and one-year-old tumours showed evidence of selection on the surviving neoplasms. Induction of highly competitive clones in transgenic mice increased early tumour removal, whereas pharmacological inhibition of clonal competition reduced tumour loss. These results support a model in which survival of early neoplasms depends on their competitive fitness relative to that of mutant clones in the surrounding normal tissue. Mutant clones in normal epithelium have an unexpected anti-tumorigenic role in purging early tumours through cell competition, thereby preserving tissue integrity.


Assuntos
Competição entre as Células , Proliferação de Células , Células Clonais/citologia , Células Clonais/metabolismo , Células Epiteliais/citologia , Neoplasias Esofágicas/patologia , Mutação , Animais , Carcinogênese/imunologia , Morte Celular , Sobrevivência Celular , Modelos Animais de Doenças , Células Epiteliais/imunologia , Células Epiteliais/patologia , Epitélio/imunologia , Neoplasias Esofágicas/imunologia , Feminino , Masculino , Camundongos , Fatores de Tempo
2.
J Neurosci ; 43(42): 7028-7040, 2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37669861

RESUMO

Parkinson's disease (PD) and progressive supranuclear palsy (PSP) both impair response inhibition, exacerbating impulsivity. Inhibitory control deficits vary across individuals and are linked with worse prognosis, and lack improvement on dopaminergic therapy. Motor and cognitive control are associated with noradrenergic innervation of the cortex, arising from the locus coeruleus (LC) noradrenergic system. Here we test the hypothesis that structural variation of the LC explains response inhibition deficits in PSP and PD. Twenty-four people with idiopathic PD, 14 with PSP-Richardson's syndrome, and 24 age- and sex-matched controls undertook a stop-signal task and ultrahigh field 7T magnetization-transfer-weighted imaging of the LC. Parameters of "race models" of go- versus stop-decisions were estimated using hierarchical Bayesian methods to quantify the cognitive processes of response inhibition. We tested the multivariate relationship between LC integrity and model parameters using partial least squares. Both disorders impaired response inhibition at the group level. PSP caused a distinct pattern of abnormalities in inhibitory control with a paradoxically reduced threshold for go responses, but longer nondecision times, and more lapses of attention. The variation in response inhibition correlated with the variability of LC integrity across participants in both clinical groups. Structural imaging of the LC, coupled with behavioral modeling in parkinsonian disorders, confirms that LC integrity is associated with response inhibition and LC degeneration contributes to neurobehavioral changes. The noradrenergic system is therefore a promising target to treat impulsivity in these conditions. The optimization of noradrenergic treatment is likely to benefit from stratification according to LC integrity.SIGNIFICANCE STATEMENT Response inhibition deficits contribute to clinical symptoms and poor outcomes in people with Parkinson's disease and progressive supranuclear palsy. We used cognitive modeling of performance of a response inhibition task to identify disease-specific mechanisms of abnormal inhibitory control. Response inhibition in both patient groups was associated with the integrity of the noradrenergic locus coeruleus, which we measured in vivo using ultra-high field MRI. We propose that the imaging biomarker of locus coeruleus integrity provides a trans-diagnostic tool to explain individual differences in response inhibition ability beyond the classic nosological borders and diagnostic criteria. Our data suggest a potential new stratified treatment approach for Parkinson's disease and progressive supranuclear palsy.


Assuntos
Doença de Parkinson , Transtornos Parkinsonianos , Paralisia Supranuclear Progressiva , Humanos , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Paralisia Supranuclear Progressiva/psicologia , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico por imagem , Locus Cerúleo , Teorema de Bayes
3.
Ann Neurol ; 93(1): 142-154, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36321699

RESUMO

OBJECTIVE: Synaptic loss is an early feature of neurodegenerative disease models, and is severe in post mortem clinical studies, including frontotemporal dementia. Positron emission tomography (PET) with radiotracers that bind to synaptic vesicle glycoprotein 2A enables quantification of synaptic density in vivo. This study used [11 C]UCB-J PET in participants with behavioral variant frontotemporal dementia (bvFTD), testing the hypothesis that synaptic loss is severe and related to clinical severity. METHODS: Eleven participants with clinically probable bvFTD and 25 age- and sex-matched healthy controls were included. Participants underwent dynamic [11 C]UCB-J PET, structural magnetic resonance imaging, and a neuropsychological battery, including the revised Addenbrooke Cognitive Examination, and INECO frontal screening. General linear models compared [11 C]UCB-J binding potential maps and gray matter volume between groups, and assessed associations between synaptic density and clinical severity in patients. Analyses were also performed using partial volume corrected [11 C]UCB-J binding potential from regions of interest (ROIs). RESULTS: Patients with bvFTD showed severe synaptic loss compared to controls. [11 C]UCB-J binding was reduced bilaterally in medial and dorsolateral frontal regions, inferior frontal gyri, anterior and posterior cingulate gyrus, insular cortex, and medial temporal lobe. Synaptic loss in the frontal and cingulate regions correlated significantly with cognitive impairments. Synaptic loss was more severe than atrophy. Results from ROI-based analyses mirrored the voxelwise results. INTERPRETATION: In accordance with preclinical models, and human postmortem evidence, there is widespread frontotemporal loss of synapses in symptomatic bvFTD, in proportion to severity. [11 C]UCB-J PET could support translational studies and experimental medicine strategies for new disease-modifying treatments for neurodegeneration. ANN NEUROL 2023;93:142-154.


Assuntos
Demência Frontotemporal , Doenças Neurodegenerativas , Doença de Pick , Humanos , Demência Frontotemporal/diagnóstico por imagem , Demência Frontotemporal/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Lobo Frontal , Encéfalo/metabolismo
4.
Phys Rev Lett ; 132(9): 092501, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38489643

RESUMO

Three ΔI=1 bands with the πg_{9/2}⊗νg_{9/2} configuration have been identified in _{35}^{74}Br_{39}. Angular distribution, linear polarization, and lifetime measurements were performed to determine the multipolarity, type, mixing ratio, and absolute transition probability of the transitions. By comparing these experimental observations with the corresponding fingerprints and the quantum particle rotor model calculations, the second and third lowest bands are, respectively, suggested as the chiral partner and one-phonon wobbling excitation built on the yrast band. The evidence indicates the first chiral wobbler in nuclei.

5.
Mov Disord ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671545

RESUMO

BACKGROUND/OBJECTIVE: The corticobasal syndrome (CBS) is a complex asymmetric movement disorder, with cognitive impairment. Although commonly associated with the primary 4-repeat-tauopathy of corticobasal degeneration, clinicopathological correlation is poor, and a significant proportion is due to Alzheimer's disease (AD). Synaptic loss is a pathological feature of many clinical and preclinical tauopathies. We therefore measured the degree of synaptic loss in patients with CBS and tested whether synaptic loss differed according to ß-amyloid status. METHODS: Twenty-five people with CBS, and 32 age-/sex-/education-matched healthy controls participated. Regional synaptic density was estimated by [11C]UCB-J non-displaceable binding potential (BPND), AD-tau pathology by [18F]AV-1451 BPND, and gray matter volume by T1-weighted magnetic resonance imaging. Participants with CBS had ß-amyloid imaging with 11C-labeled Pittsburgh Compound-B ([11C]PiB) positron emission tomography. Symptom severity was assessed with the progressive supranuclear palsy-rating-scale, the cortical basal ganglia functional scale, and the revised Addenbrooke's Cognitive Examination. Regional differences in BPND and gray matter volume between groups were assessed by ANOVA. RESULTS: Compared to controls, patients with CBS had higher [18F]AV-1451 uptake, gray matter volume loss, and reduced synaptic density. Synaptic loss was more severe and widespread in the ß-amyloid negative group. Asymmetry of synaptic loss was in line with the clinically most affected side. DISCUSSION: Distinct patterns of [11C]UCB-J and [18F]AV-1451 binding and gray matter volume loss, indicate differences in the pathogenic mechanisms of CBS according to whether it is associated with the presence of Alzheimer's disease or not. This highlights the potential for different therapeutic strategies in CBSs. © 2024 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

6.
Psychol Med ; : 1-10, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38721761

RESUMO

BACKGROUND: We examined whether cannabis use contributes to the increased risk of psychotic disorder for non-western minorities in Europe. METHODS: We used data from the EU-GEI study (collected at sites in Spain, Italy, France, the United Kingdom, and the Netherlands) on 825 first-episode patients and 1026 controls. We estimated the odds ratio (OR) of psychotic disorder for several groups of migrants compared with the local reference population, without and with adjustment for measures of cannabis use. RESULTS: The OR of psychotic disorder for non-western minorities, adjusted for age, sex, and recruitment area, was 1.80 (95% CI 1.39-2.33). Further adjustment of this OR for frequency of cannabis use had a minimal effect: OR = 1.81 (95% CI 1.38-2.37). The same applied to adjustment for frequency of use of high-potency cannabis. Likewise, adjustments of ORs for most sub-groups of non-western countries had a minimal effect. There were two exceptions. For the Black Caribbean group in London, after adjustment for frequency of use of high-potency cannabis the OR decreased from 2.45 (95% CI 1.25-4.79) to 1.61 (95% CI 0.74-3.51). Similarly, the OR for Surinamese and Dutch Antillean individuals in Amsterdam decreased after adjustment for daily use: from 2.57 (95% CI 1.07-6.15) to 1.67 (95% CI 0.62-4.53). CONCLUSIONS: The contribution of cannabis use to the excess risk of psychotic disorder for non-western minorities was small. However, some evidence of an effect was found for people of Black Caribbean heritage in London and for those of Surinamese and Dutch Antillean heritage in Amsterdam.

7.
Brain ; 146(8): 3221-3231, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-36883644

RESUMO

Frontotemporal dementia is clinically and neuropathologically heterogeneous, but neuroinflammation, atrophy and cognitive impairment occur in all of its principal syndromes. Across the clinical spectrum of frontotemporal dementia, we assess the predictive value of in vivo neuroimaging measures of microglial activation and grey-matter volume on the rate of future cognitive decline. We hypothesized that inflammation is detrimental to cognitive performance, in addition to the effect of atrophy. Thirty patients with a clinical diagnosis of frontotemporal dementia underwent a baseline multimodal imaging assessment, including [11C]PK11195 PET to index microglial activation and structural MRI to quantify grey-matter volume. Ten people had behavioural variant frontotemporal dementia, 10 had the semantic variant of primary progressive aphasia and 10 had the non-fluent agrammatic variant of primary progressive aphasia. Cognition was assessed at baseline and longitudinally with the revised Addenbrooke's Cognitive Examination, at an average of 7-month intervals (for an average of ∼2 years, up to ∼5 years). Regional [11C]PK11195 binding potential and grey-matter volume were determined, and these were averaged within four hypothesis-driven regions of interest: bilateral frontal and temporal lobes. Linear mixed-effect models were applied to the longitudinal cognitive test scores, with [11C]PK11195 binding potentials and grey-matter volumes as predictors of cognitive performance, with age, education and baseline cognitive performance as covariates. Faster cognitive decline was associated with reduced baseline grey-matter volume and increased microglial activation in frontal regions, bilaterally. In frontal regions, microglial activation and grey-matter volume were negatively correlated, but provided independent information, with inflammation the stronger predictor of the rate of cognitive decline. When clinical diagnosis was included as a factor in the models, a significant predictive effect was found for [11C]PK11195 BPND in the left frontal lobe (-0.70, P = 0.01), but not for grey-matter volumes (P > 0.05), suggesting that inflammation severity in this region relates to cognitive decline regardless of clinical variant. The main results were validated by two-step prediction frequentist and Bayesian estimation of correlations, showing significant associations between the estimated rate of cognitive change (slope) and baseline microglial activation in the frontal lobe. These findings support preclinical models in which neuroinflammation (by microglial activation) accelerates the neurodegenerative disease trajectory. We highlight the potential for immunomodulatory treatment strategies in frontotemporal dementia, in which measures of microglial activation may also improve stratification for clinical trials.


Assuntos
Afasia Primária Progressiva , Disfunção Cognitiva , Demência Frontotemporal , Doenças Neurodegenerativas , Doença de Pick , Humanos , Demência Frontotemporal/metabolismo , Doenças Neuroinflamatórias , Doenças Neurodegenerativas/patologia , Microglia/metabolismo , Teorema de Bayes , Lobo Frontal/patologia , Doença de Pick/patologia , Disfunção Cognitiva/metabolismo , Imageamento por Ressonância Magnética/métodos , Inflamação/patologia , Atrofia/patologia , Afasia Primária Progressiva/patologia
8.
Brain ; 146(8): 3232-3242, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-36975168

RESUMO

The advent of clinical trials of disease-modifying agents for neurodegenerative disease highlights the need for evidence-based end point selection. Here we report the longitudinal PROSPECT-M-UK study of progressive supranuclear palsy (PSP), corticobasal syndrome (CBS), multiple system atrophy (MSA) and related disorders, to compare candidate clinical trial end points. In this multicentre UK study, participants were assessed with serial questionnaires, motor examination, neuropsychiatric and MRI assessments at baseline, 6 and 12 months. Participants were classified by diagnosis at baseline and study end, into Richardson syndrome, PSP-subcortical (PSP-parkinsonism and progressive gait freezing subtypes), PSP-cortical (PSP-frontal, PSP-speech and language and PSP-CBS subtypes), MSA-parkinsonism, MSA-cerebellar, CBS with and without evidence of Alzheimer's disease pathology and indeterminate syndromes. We calculated annual rate of change, with linear mixed modelling and sample sizes for clinical trials of disease-modifying agents, according to group and assessment type. Two hundred forty-three people were recruited [117 PSP, 68 CBS, 42 MSA and 16 indeterminate; 138 (56.8%) male; age at recruitment 68.7 ± 8.61 years]. One hundred and fifty-nine completed the 6-month assessment (82 PSP, 27 CBS, 40 MSA and 10 indeterminate) and 153 completed the 12-month assessment (80 PSP, 29 CBS, 35 MSA and nine indeterminate). Questionnaire, motor examination, neuropsychiatric and neuroimaging measures declined in all groups, with differences in longitudinal change between groups. Neuroimaging metrics would enable lower sample sizes to achieve equivalent power for clinical trials than cognitive and functional measures, often achieving N < 100 required for 1-year two-arm trials (with 80% power to detect 50% slowing). However, optimal outcome measures were disease-specific. In conclusion, phenotypic variance within PSP, CBS and MSA is a major challenge to clinical trial design. Our findings provide an evidence base for selection of clinical trial end points, from potential functional, cognitive, clinical or neuroimaging measures of disease progression.


Assuntos
Atrofia de Múltiplos Sistemas , Transtornos Parkinsonianos , Paralisia Supranuclear Progressiva , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Feminino , Transtornos Parkinsonianos/diagnóstico por imagem , Transtornos Parkinsonianos/tratamento farmacológico , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Paralisia Supranuclear Progressiva/patologia , Atrofia de Múltiplos Sistemas/diagnóstico por imagem , Atrofia de Múltiplos Sistemas/patologia , Imageamento por Ressonância Magnética , Reino Unido
9.
J Sports Sci ; 42(7): 559-565, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38734977

RESUMO

Modern technology challenges anecdotal beliefs on baseball performance. The study's purpose examines these beliefs by classifying batted ball outcomes. Three categories of independent variables (anthropometry, in-game situation, technique-based), from 1,922 batted ball outcomes produced by 230 players, were used to classify the likelihood of hits during 2021 college baseball games. Anthropometry included player's heights and weights. In-game situation entailed batter side, same side, ahead count, and pitch type. Technique-based variables measured by TrackMan radar included exit speed (ExSp), launch angle (LA), batted ball distance (BBD), and hang time (HT). Binary logistic regression analysis was performed with batted ball outcome as the dependent variable. Independent variables provided a good fit (χ2 (10) = 522.358, p < 0.01) and correctly classified nearly three-fourths of outcomes. Height (ß = 0.030, p < 0.05), ExSp (ß = 0.023, p < 0.05), LA (ß = 0.028, p < 0.01), and BBD (ß = 0.067, p < 0.01) each had significant positive associations, yet HT (ß = -1.661, p < 0.01) had a significant negative association, with batted ball outcomes. TrackMan provided four significant independent variables. Anthropometry's contribution to batting outcome was modest, while in-game situation's impact was non-significant; results contradict anecdotal beliefs of their importance.


Assuntos
Antropometria , Desempenho Atlético , Beisebol , Humanos , Desempenho Atlético/classificação , Desempenho Atlético/fisiologia , Adulto Jovem , Masculino , Destreza Motora/fisiologia , Destreza Motora/classificação
10.
Hum Brain Mapp ; 44(11): 4239-4255, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37269181

RESUMO

There is a pressing need to understand the factors that predict prognosis in progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS), with high heterogeneity over the poor average survival. We test the hypothesis that the magnitude and distribution of connectivity changes in PSP and CBS predict the rate of progression and survival time, using datasets from the Cambridge Centre for Parkinson-plus and the UK National PSP Research Network (PROSPECT-MR). Resting-state functional MRI images were available from 146 participants with PSP, 82 participants with CBS, and 90 healthy controls. Large-scale networks were identified through independent component analyses, with correlations taken between component time series. Independent component analysis was also used to select between-network connectivity components to compare with baseline clinical severity, longitudinal rate of change in severity, and survival. Transdiagnostic survival predictors were identified using partial least squares regression for Cox models, with connectivity compared to patients' demographics, structural imaging, and clinical scores using five-fold cross-validation. In PSP and CBS, between-network connectivity components were identified that differed from controls, were associated with disease severity, and were related to survival and rate of change in clinical severity. A transdiagnostic component predicted survival beyond demographic and motion metrics but with lower accuracy than an optimal model that included the clinical and structural imaging measures. Cortical atrophy enhanced the connectivity changes that were most predictive of survival. Between-network connectivity is associated with variability in prognosis in PSP and CBS but does not improve predictive accuracy beyond clinical and structural imaging metrics.


Assuntos
Degeneração Corticobasal , Doenças Neurodegenerativas , Paralisia Supranuclear Progressiva , Humanos , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Prognóstico , Doenças Neurodegenerativas/diagnóstico por imagem
11.
Mov Disord ; 38(7): 1316-1326, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37171832

RESUMO

BACKGROUND: Synaptic loss is characteristic of many neurodegenerative diseases; it occurs early and is strongly related to functional deficits. OBJECTIVE: In this longitudinal observational study, we determine the rate at which synaptic density is reduced in the primary tauopathies of progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD), and we test the relationship with disease progression. METHODS: Our cross-sectional cohort included 32 participants with probable PSP and 16 with probable CBD (all amyloid-negative corticobasal syndrome), recruited from tertiary care centers in the United Kingdom, and 33 sex- and age-matched healthy control subjects. Synaptic density was estimated by positron emission tomography imaging with the radioligand [11 C]UCB-J that binds synaptic vesicle 2A. Clinical severity and cognition were assessed by the PSP Rating Scale and the Addenbrooke's cognitive examination. Regional [11 C]UCB-J nondisplaceable binding potential was estimated in Hammersmith Atlas regions of interest. Twenty-two participants with PSP/CBD had a follow-up [11 C]UCB-J positron emission tomography scan after 1 year. We calculated the annualized change in [11 C]UCB-J nondisplaceable binding potential and correlated this with the change in clinical severity. RESULTS: We found significant annual synaptic loss within the frontal lobe (-3.5%, P = 0.03) and the right caudate (-3.9%, P = 0.046). The degree of longitudinal synaptic loss within the frontal lobe correlated with the rate of change in the PSP Rating Scale (R = 0.47, P = 0.03) and cognition (Addenbrooke's Cognitive Examination-Revised, R = -0.62, P = 0.003). CONCLUSIONS: We provide in vivo evidence for rapid progressive synaptic loss, correlating with clinical progression in primary tauopathies. Synaptic loss may be an important therapeutic target and outcome variable for early-phase clinical trials of disease-modifying treatments. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Transtornos dos Movimentos , Paralisia Supranuclear Progressiva , Tauopatias , Humanos , Estudos Transversais , Tomografia por Emissão de Pósitrons/métodos , Tauopatias/diagnóstico por imagem , Tauopatias/metabolismo , Paralisia Supranuclear Progressiva/diagnóstico , Transtornos dos Movimentos/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo
12.
PLoS Comput Biol ; 18(5): e1010079, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35533200

RESUMO

Apathy is a debilitating feature of many neuropsychiatric diseases, that is typically described as a reduction of goal-directed behaviour. Despite its prevalence and prognostic importance, the mechanisms underlying apathy remain controversial. Degeneration of the locus coeruleus-noradrenaline system is known to contribute to motivational deficits, including apathy. In healthy people, noradrenaline has been implicated in signalling the uncertainty of expectations about the environment. We proposed that noradrenergic deficits contribute to apathy by modulating the relative weighting of prior beliefs about action outcomes. We tested this hypothesis in the clinical context of Parkinson's disease, given its associations with apathy and noradrenergic dysfunction. Participants with mild-to-moderate Parkinson's disease (N = 17) completed a randomised double-blind, placebo-controlled, crossover study with 40 mg of the noradrenaline reuptake inhibitor atomoxetine. Prior weighting was inferred from psychophysical analysis of performance in an effort-based visuomotor task, and was confirmed as negatively correlated with apathy. Locus coeruleus integrity was assessed in vivo using magnetisation transfer imaging at ultra-high field 7T. The effect of atomoxetine depended on locus coeruleus integrity: participants with a more degenerate locus coeruleus showed a greater increase in prior weighting on atomoxetine versus placebo. The results indicate a contribution of the noradrenergic system to apathy and potential benefit from noradrenergic treatment of people with Parkinson's disease, subject to stratification according to locus coeruleus integrity. More broadly, these results reconcile emerging predictive processing accounts of the role of noradrenaline in goal-directed behaviour with the clinical symptom of apathy and its potential pharmacological treatment.


Assuntos
Apatia , Doença de Parkinson , Cloridrato de Atomoxetina/farmacologia , Estudos Cross-Over , Humanos , Norepinefrina , Doença de Parkinson/complicações , Doença de Parkinson/tratamento farmacológico
13.
Brain ; 145(1): 340-348, 2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-34398211

RESUMO

The relationship between in vivo synaptic density and molecular pathology in primary tauopathies is key to understanding the impact of tauopathy on functional decline and in informing new early therapeutic strategies. In this cross-sectional observational study, we determine the in vivo relationship between synaptic density and molecular pathology in the primary tauopathies of progressive supranuclear palsy and corticobasal degeneration as a function of disease severity. Twenty-three patients with progressive supranuclear palsy and 12 patients with corticobasal syndrome were recruited from a tertiary referral centre. Nineteen education-, sex- and gender-matched control participants were recruited from the National Institute for Health Research 'Join Dementia Research' platform. Cerebral synaptic density and molecular pathology, in all participants, were estimated using PET imaging with the radioligands 11C-UCB-J and 18F-AV-1451, respectively. Patients with corticobasal syndrome also underwent amyloid PET imaging with 11C-PiB to exclude those with likely Alzheimer's pathology-we refer to the amyloid-negative cohort as having corticobasal degeneration, although we acknowledge other underlying pathologies exist. Disease severity was assessed with the progressive supranuclear palsy rating scale; regional non-displaceable binding potentials of 11C-UCB-J and 18F-AV-1451 were estimated in regions of interest from the Hammersmith Atlas, excluding those with known off-target binding for 18F-AV-1451. As an exploratory analysis, we also investigated the relationship between molecular pathology in cortical brain regions and synaptic density in subcortical areas. Across brain regions, there was a positive correlation between 11C-UCB-J and 18F-AV-1451 non-displaceable binding potentials (ß = 0.4, t = 3.6, P = 0.001), independent of age or time between PET scans. However, this correlation became less positive as a function of disease severity in patients (ß = -0.02, t = -2.9, P = 0.007, R = -0.41). Between regions, cortical 18F-AV-1451 binding was negatively correlated with synaptic density in subcortical areas (caudate nucleus, putamen). Brain regions with higher synaptic density are associated with a higher 18F-AV-1451 binding in progressive supranuclear palsy/corticobasal degeneration, but this association diminishes with disease severity. Moreover, higher cortical 18F-AV-1451 binding correlates with lower subcortical synaptic density. Longitudinal imaging is required to confirm the mediation of synaptic loss by molecular pathology. However, the effect of disease severity suggests a biphasic relationship between synaptic density and molecular pathology with synapse-rich regions vulnerable to accrual of pathological aggregates, followed by a loss of synapses in response to the molecular pathology. Given the importance of synaptic function for cognition and action, our study elucidates the pathophysiology of primary tauopathies and may inform the design of future clinical trials.


Assuntos
Doença de Alzheimer , Paralisia Supranuclear Progressiva , Tauopatias , Doença de Alzheimer/patologia , Encéfalo/patologia , Carbolinas , Radioisótopos de Carbono/metabolismo , Estudos Transversais , Humanos , Patologia Molecular , Tomografia por Emissão de Pósitrons/métodos , Piridinas , Pirrolidinonas , Paralisia Supranuclear Progressiva/metabolismo , Tauopatias/metabolismo , Proteínas tau/metabolismo
14.
Alzheimers Dement ; 19(5): 1947-1962, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36377606

RESUMO

INTRODUCTION: We tested whether changes in functional networks predict cognitive decline and conversion from the presymptomatic prodrome to symptomatic disease in familial frontotemporal dementia (FTD). METHODS: For hypothesis generation, 36 participants with behavioral variant FTD (bvFTD) and 34 controls were recruited from one site. For hypothesis testing, we studied 198 symptomatic FTD mutation carriers, 341 presymptomatic mutation carriers, and 329 family members without mutations. We compared functional network dynamics between groups, with clinical severity and with longitudinal clinical progression. RESULTS: We identified a characteristic pattern of dynamic network changes in FTD, which correlated with neuropsychological impairment. Among presymptomatic mutation carriers, this pattern of network dynamics was found to a greater extent in those who subsequently converted to the symptomatic phase. Baseline network dynamic changes predicted future cognitive decline in symptomatic participants and older presymptomatic participants. DISCUSSION: Dynamic network abnormalities in FTD predict cognitive decline and symptomatic conversion. HIGHLIGHTS: We investigated brain network predictors of dementia symptom onset Frontotemporal dementia results in characteristic dynamic network patterns Alterations in network dynamics are associated with neuropsychological impairment Network dynamic changes predict symptomatic conversion in presymptomatic carriers Network dynamic changes are associated with longitudinal cognitive decline.


Assuntos
Disfunção Cognitiva , Demência Frontotemporal , Humanos , Demência Frontotemporal/diagnóstico , Mutação/genética , Encéfalo , Disfunção Cognitiva/genética , Imageamento por Ressonância Magnética
15.
J Vasc Surg ; 76(1): 202-208, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35149162

RESUMO

OBJECTIVES: Strategies of balloon dilation during transfemoral carotid artery stenting include prestent dilation only (PRE), post-stent dilation only (POST), or both predilation and postdilation (PRE+POST). Concerns over higher neurological risk have been raised with POST and PRE+POST during transfemoral carotid artery stenting. Whether these concerns are applicable to transcarotid artery revascularization (TCAR), which uses proximal clamping and cerebral blood flow reversal during stent deployment and balloon angioplasty remains unknown. Our aim is to analyze outcomes of PRE, POST, or PRE+POST balloon dilation strategies during TCAR. METHODS: We analyzed the prospectively collected data from the ROADSTER1 (pivotal), ROADSTER2 (US Food and Drug Administration indicated postmarket), and ROADSTER Extended Access TCAR trials. All trial patients had a high risk anatomic or clinical factors for carotid endarterectomy and were included, unless they did not undergo stent deployment or balloon dilation. For trial inclusion, asymptomatic patients had a carotid stenosis of more than 80%, and symptomatic patients had stenosis of more than 50%. Primary outcome measures were stroke, death, and myocardial infarction (MI) at 30 days. Data were statistically analyzed with χ2, analysis of variance, and multivariable analysis, as appropriate. RESULTS: There were 851 patients (566 male) who underwent dilation by PRE (n = 216), POST (n = 249), or PRE+POST (n = 386). Patients had carotid stenosis of greater than 70% (n = 828, 97%), and 207 (24%) were symptomatic. Flow reversal times were longer in the PRE+POST group (PRE 10.2 minutes, POST 9.8 minutes, and PRE+POST 13.3 minutes; P < .001). The 30-day stroke rate for the whole cohort was 1.9%, mortality was 0.5%, and MI rate was 0.94%. Stroke rates for the PRE cohort (1.9%), POST cohort (2.0%), and PRE+POST cohort (1.8%; P = .98) were similar. Also, death rates at 30 days, and composite stroke, death, and MI rates were similar in the three cohorts. No significant differences in adverse outcomes were noted among the various dilation strategies for both symptomatic and asymptomatic patients. CONCLUSIONS: Based on these prospective trial data, there is no difference in neurological complications owing to balloon dilation strategy during TCAR. The balloon dilation technique best suited to the patient's specific lesion morphology should be used. Further studies are needed to evaluate the relationship of these dilation strategies to long-term outcomes, including stent patency, restenosis, and reintervention.


Assuntos
Estenose das Carótidas , Infarto do Miocárdio , Acidente Vascular Cerebral , Artérias , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/terapia , Dilatação/efeitos adversos , Humanos , Masculino , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco , Stents/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
16.
Opt Lett ; 47(3): 710-713, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35103714

RESUMO

We investigate the optical trapping of polystyrene microspheres in optical tweezers. The transverse capture gradient forces of polystyrene microspheres with different numerical aperture are theoretically and experimentally evaluated by the power spectral density roll-off method. It is found that the trapping force of the experimental measurement is much stronger than that of the theoretical results. The discordance is attributed to the slow light effect near the focus, which has been found in recent years [Science347, 857 (2015)10.1126/science.aaa3035; Opt. Express18, 10822 (2010)10.1364/OE.18.010822; Opt. Commun.332, 164 (2014)10.1016/j.optcom.2014.06.057]. The modified trapping force of the theoretical results by considering the slow light effect near the focus is well consistent with that of the experimental results.


Assuntos
Pinças Ópticas , Poliestirenos , Microesferas
17.
Mov Disord ; 37(8): 1663-1672, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35576973

RESUMO

BACKGROUND: Neurodegeneration in the locus coeruleus (LC) contributes to neuropsychiatric symptoms in both Parkinson's disease (PD) and progressive supranuclear palsy (PSP). Spatial precision of LC imaging is improved with ultrahigh field 7 T magnetic resonance imaging. OBJECTIVES: This study aimed to characterize the spatial patterns of LC pathological change in PD and PSP and the transdiagnostic relationship between LC signals and neuropsychiatric symptoms. METHODS: Twenty-five people with idiopathic PD, 14 people with probable PSP-Richardson's syndrome, and 24 age-matched healthy controls were recruited. Participants underwent clinical assessments and high-resolution (0.08 mm3 ) 7 T-magnetization-transfer imaging to measure LC integrity in vivo. Spatial patterns of LC change were obtained using subregional mean contrast ratios and significant LC clusters; we further correlated the LC contrast with measures of apathy and cognition, using both mixed-effect models and voxelwise analyses. RESULTS: PSP and PD groups showed significant LC degeneration in the caudal subregion relative to controls. Mixed-effect models revealed a significant interaction between disease-group and apathy-related correlations with LC degeneration (ß = 0.46, SE [standard error] = 0.17, F(1, 35) = 7.46, P = 0.01), driven by a strong correlation in PSP (ß = -0.58, SE = 0.21, t(35) = -2.76, P = 0.009). Across both disease groups, voxelwise analyses indicated that lower LC integrity was associated with worse cognition and higher apathy scores. CONCLUSIONS: The relationship between LC and nonmotor symptoms highlights a role for noradrenergic dysfunction across both PD and PSP, confirming the potential for noradrenergic therapeutic strategies to address transdiagnostic cognitive and behavioral features in neurodegenerative disease. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Locus Cerúleo , Transtornos Parkinsonianos , Apatia/fisiologia , Cognição/fisiologia , Humanos , Locus Cerúleo/diagnóstico por imagem , Locus Cerúleo/patologia , Imageamento por Ressonância Magnética , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/fisiopatologia , Transtornos Parkinsonianos/diagnóstico por imagem , Transtornos Parkinsonianos/fisiopatologia , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Paralisia Supranuclear Progressiva/fisiopatologia
18.
Eur Biophys J ; 51(2): 185-191, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35018482

RESUMO

High-throughput single-cell analysis based on physical properties (such as morphology or mechanics) is emerging as a powerful tool to inform clinical research, with a great potential for translation towards diagnosis. Here we present a novel microfluidic approach adopting acoustic waves to manipulate and mechanically stimulate single cells, and interferometry to track changes in the morphology and measure size, deformability, and refractive index of non-adherent cells. The method is based on the integration within the acoustofluidic channel of a low-finesse Fabry-Perot resonator, providing very high sensitivity and a speed potentially suitable to obtain the high-throughput necessary to handle the variability stemming from the biological diversity of single cells. The proposed approach is applied to a set of different samples: reference polystyrene beads, algae and yeast. The results demonstrate the capability of the acoustofluidic interferometric device to detect and quantify optomechanical properties of single cells with a throughput suitable to address label-free single-cell clinical analysis.


Assuntos
Acústica , Som , Interferometria , Microfluídica , Poliestirenos
19.
Brain ; 144(8): 2513-2526, 2021 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-33783470

RESUMO

Cognitive decline is a common feature of Parkinson's disease, and many of these cognitive deficits fail to respond to dopaminergic therapy. Therefore, targeting other neuromodulatory systems represents an important therapeutic strategy. Among these, the locus coeruleus-noradrenaline system has been extensively implicated in response inhibition deficits. Restoring noradrenaline levels using the noradrenergic reuptake inhibitor atomoxetine can improve response inhibition in some patients with Parkinson's disease, but there is considerable heterogeneity in treatment response. Accurately predicting the patients who would benefit from therapies targeting this neurotransmitter system remains a critical goal, in order to design the necessary clinical trials with stratified patient selection to establish the therapeutic potential of atomoxetine. Here, we test the hypothesis that integrity of the noradrenergic locus coeruleus explains the variation in improvement of response inhibition following atomoxetine. In a double-blind placebo-controlled randomized crossover design, 19 patients with Parkinson's disease completed an acute psychopharmacological challenge with 40 mg of oral atomoxetine or placebo. A stop-signal task was used to measure response inhibition, with stop-signal reaction times obtained through hierarchical Bayesian estimation of an ex-Gaussian race model. Twenty-six control subjects completed the same task without undergoing the drug manipulation. In a separate session, patients and controls underwent ultra-high field 7 T imaging of the locus coeruleus using a neuromelanin-sensitive magnetization transfer sequence. The principal result was that atomoxetine improved stop-signal reaction times in those patients with lower locus coeruleus integrity. This was in the context of a general impairment in response inhibition, as patients on placebo had longer stop-signal reaction times compared to controls. We also found that the caudal portion of the locus coeruleus showed the largest neuromelanin signal decrease in the patients compared to controls. Our results highlight a link between the integrity of the noradrenergic locus coeruleus and response inhibition in patients with Parkinson's disease. Furthermore, they demonstrate the importance of baseline noradrenergic state in determining the response to atomoxetine. We suggest that locus coeruleus neuromelanin imaging offers a marker of noradrenergic capacity that could be used to stratify patients in trials of noradrenergic therapy and to ultimately inform personalized treatment approaches.


Assuntos
Inibidores da Captação Adrenérgica/farmacologia , Cloridrato de Atomoxetina/farmacologia , Inibição Psicológica , Locus Cerúleo/diagnóstico por imagem , Doença de Parkinson/diagnóstico por imagem , Idoso , Método Duplo-Cego , Feminino , Humanos , Locus Cerúleo/efeitos dos fármacos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tempo de Reação/efeitos dos fármacos
20.
J Endocrinol Invest ; 45(3): 617-627, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34655038

RESUMO

OBJECTS: Cushing's disease (CD) is the most common cause of ACTH-dependent hypercortisolism in children age ≥ 7. The utility of bilateral inferior petrosal sinus sampling (BIPSS), an important test in adults, is less defined in children. We present a case series of children with ACTH-dependent hypercortisolemia and review the literature to assess the utility of BIPSS in the diagnosis and localization of CD. METHODS: We performed an IRB-approved chart review of patients aged ≤ 18 with ACTH-dependent hypercortisolism at MGH between 2000 and 2019 and collected clinical, laboratory, radiographic, BIPSS, surgical, and outcomes data. RESULTS: In our cohort (n = 21), BIPSS had a sensitivity of 93% and specificity of 100% for diagnosis of CD. Compared to surgery, successful BIPSS correctly predicted adenoma laterality in 69% of cases vs. 70% by MRI. Among patients with lesions ≥ 4 mm (n = 9), BIPSS correctly lateralized in 50% vs. 100% by MRI. In patients with subtle lesions (< 4 mm, n = 7), BIPSS correctly lateralized in 80% vs. 71% by MRI. In patients (n = 4) with CD and negative MRIs, BIPSS correctly lateralized in 75% cases. Surgical cure was achieved in 90% of patients and 95% of patients had long-term disease control. CONCLUSIONS: In our cohort (n = 21; n = 20 CD, n = 1 ectopic ACTH secretion), BIPSS was sensitive and specific for the diagnosis of CD. Compared to MRI, BIPSS was not additionally helpful for lateralization in patients with lesions ≥ 4 mm on MRI. BIPSS was helpful in guiding surgical exploration and achieving immediate postoperative remission among patients with subtle and negative MRI findings.


Assuntos
Hormônio Adrenocorticotrópico/sangue , Hipofisectomia/métodos , Amostragem do Seio Petroso/métodos , Hipersecreção Hipofisária de ACTH , Neoplasias Hipofisárias , Adolescente , Índice de Massa Corporal , Feminino , Humanos , Hidrocortisona/urina , Imageamento por Ressonância Magnética/métodos , Masculino , Hipersecreção Hipofisária de ACTH/sangue , Hipersecreção Hipofisária de ACTH/diagnóstico , Hipersecreção Hipofisária de ACTH/patologia , Hipersecreção Hipofisária de ACTH/cirurgia , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/patologia , Neoplasias Hipofisárias/cirurgia , Indução de Remissão/métodos , Reprodutibilidade dos Testes , Tempo , Resultado do Tratamento
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