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1.
Epilepsia Open ; 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39400461

RESUMO

OBJECTIVE: To assess whether the antiseizure medication levetiracetam may improve cognition in individuals with Alzheimer's disease who have not previously experienced a seizure. METHODS: We performed a randomized, double-blind, placebo-controlled crossover pilot study in individuals with mild-to-moderate Alzheimer's disease. Electroencephalography was performed at baseline and those with active epileptiform discharges were excluded. Eligible participants were randomized to placebo for 12 weeks or an active arm of oral levetiracetam (4 weeks up-titration to levetiracetam 500 mg twice daily, 4 weeks maintained on this dose followed by 4 weeks down-titration to nil). Participants then crossed over to the other arm. The primary outcome was change in cognitive function assessed by the Oxford Memory Task, a task sensitive to hippocampal memory binding. Secondary outcomes included tolerability, other neuropsychological scales, and general questionnaires. RESULTS: Recruitment numbers were severely limited owing to restrictions from the COVID-19 pandemic at the time of the study. Eight participants completed both arms of the study (mean age 68.4 years [SD = 9.2]; 5 females [62.5%]). No participants withdrew from the study and there was no significant difference between reported side effects in the active levetiracetam or placebo arm. Measures of mood and quality of life were also not significantly different between the two arms based on participant or carer reports. In limited data analysis, there was no statistically significant difference between participants in the active levetiracetam and placebo arm on the memory task. SIGNIFICANCE: This pilot study demonstrates that levetiracetam was well tolerated in individuals with Alzheimer's disease who do not have a history of seizures and has no detrimental effect on mood or quality of life. Larger studies are needed to assess whether levetiracetam may have a positive effect on cognitive function in subsets of individuals with Alzheimer's disease. PLAIN LANGUAGE SUMMARY: Abnormal electrical activity within the brain, such as is seen in seizures, might contribute to memory problems in people with dementia. We completed a clinical trial to see if an antiseizure medication, levetiracetam, could help with memory difficulties in people with Alzheimer's disease (the most common cause of dementia). In this pilot study, we could not prove whether levetiracetam helped memory function. We did show that the drug is safe and well tolerated in people with dementia who have not had a seizure. This work, therefore, offers a platform for future research exploring antiseizure medications in people with dementia.

2.
bioRxiv ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-39372799

RESUMO

Background: Motivational dysfunction is a core feature of depression, and can have debilitating effects on everyday function. However, it is unclear which disrupted cognitive processes underlie impaired motivation, and whether impairments persist following remission. Decision-making concerning exerting effort to collect rewards offers a promising framework for understanding motivation, especially when examined with computational tools which can offer precise quantification of latent processes. Methods: Effort-based decision-making was assessed using the Apple Gathering Task, in which participants decide whether to exert effort via a grip-force device to obtain varying levels of reward; effort levels were individually calibrated and varied parametrically. We present a comprehensive computational analysis of decision-making, initially validating our model in healthy volunteers (N=67), before applying it in a case-control study including current (N=41) and remitted (N=46) unmedicated depressed individuals, and healthy volunteers with (N=36) and without (N=57) a family history of depression. Results: Four fundamental computational mechanisms that drive patterns of effort-based decisions, which replicated across samples, were identified: an overall bias to accept effort challenges; reward sensitivity; and linear and quadratic effort sensitivity. Traditional model-agnostic analyses showed that both depressed groups showed lower willingness to exert effort. In contrast with previous findings, computational analysis revealed that this difference was driven by lower effort acceptance bias, but not altered effort or reward sensitivity. Conclusions: This work provides insight into the computational mechanisms underlying motivational dysfunction in depression. Lower willingness to exert effort could represent a trait-like factor contributing to symptoms, and might represent a fruitful target for treatment and prevention.

3.
Schizophr Bull ; 2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39312272

RESUMO

OBJECTIVE: Motivational deficits in schizophrenia are proposed to be attributable in part to abnormal effort-cost computations, calculations weighing the costs vs. the benefits of actions. Several reports have shown that people with schizophrenia display a reduced willingness to exert effort for monetary rewards when compared to controls. The primary goal of the current study was to further characterize reduced willingness to exert effort in schizophrenia by determining whether reduced willingness reflects (1) reduced sensitivity to reward, (2) increased sensitivity to effort, or (3) a combination of both. DESIGN: We assessed effort-cost decision-making in 30 controls and 30 people with schizophrenia, using 2 separate experimental tasks. Critically, one paradigm allowed for independent estimation of effects of reward and effort sensitivity on choice behavior. The other task isolated effort sensitivity by measuring effort in the absence of reward. Clinical interviews and self-report questionnaires were administered to people with schizophrenia to determine negative symptom severity. RESULTS: Across both tasks, we found evidence for reduced willingness to exert effort in people with schizophrenia compared to controls. Further, in both paradigms reduced willingness to exert effort was driven by increased sensitivity to effort in people with schizophrenia compared to controls. In contrast, measures of reward sensitivity did not significantly differ between groups. Surprisingly, we did not find correlations between task variables and measures of negative symptom severity. CONCLUSIONS AND RELEVANCE: These findings further specify prior work by identifying a specific contributory role for increased effort sensitivity in effort-cost decision-making deficits in schizophrenia.

4.
Commun Psychol ; 2(1): 87, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39313518

RESUMO

People differ in their levels of impulsivity and patience, and these preferences are heavily influenced by others. Previous research suggests that susceptibility to social influence may vary with age, but the mechanisms and whether people are more influenced by patience or impulsivity remain unknown. Here, using a delegated inter-temporal choice task and Bayesian computational models, we tested susceptibility to social influence in young (aged 18-36, N = 76) and older (aged 60-80, N = 78) adults. Participants completed a temporal discounting task and then learnt the preferences of two other people (one more impulsive and one more patient) before making their choices again. We used the signed Kullback-Leibler divergence to quantify the magnitude and direction of social influence. We found that, compared to young adults, older adults were relatively more susceptible to impulsive social influence. Factor analyses showed that older adults with higher self-reported levels of affective empathy and emotional motivation were particularly susceptible to impulsive influence. Importantly, older and young adults showed similar learning accuracy about others' preferences, and their baseline impulsivity did not differ. Together, these findings suggest highly affectively empathetic and emotionally motivated older adults may be at higher risk for impulsive decisions, due to their susceptibility to social influence.

5.
Prog Retin Eye Res ; 103: 101303, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39303763

RESUMO

Intraocular pressure (IOP) is the most important modifiable risk factor for glaucoma and fluctuates considerably within patients over short and long time periods. Our field's understanding of IOP has evolved considerably in recent years, driven by tonometric technologies with increasing accuracy, reproducibility, and temporal resolution that have refined our knowledge regarding the relationship between IOP and glaucoma risk and pathogenesis. The goal of this article is to review the published literature pertinent to the following points: 1) the factors that determine IOP in physiologic and pathologic states; 2) technologies for measuring IOP; 3) scientific and clinical rationale for measuring diverse IOP metrics in patients with glaucoma; 4) the impact and shortcomings of current standard-of-care IOP monitoring approaches; 5) recommendations for approaches to IOP monitoring that could improve patient outcomes; and 6) research questions that must be answered to improve our understanding of how IOP contributes to disease progression. Retrospective and prospective data, including that from landmark clinical trials, document greater IOP fluctuations in glaucomatous than healthy eyes, tendencies for maximal daily IOP to occur outside of office hours, and, in addition to mean and maximal IOP, an association between IOP fluctuation and glaucoma progression that is independent of mean in-office IOP. Ambulatory IOP monitoring, measuring IOP outside of office hours and at different times of day and night, provides clinicians with discrete data that could improve patient outcomes. Eye care clinicians treating glaucoma based on isolated in-office IOP measurements may make treatment decisions without fully capturing the entire IOP profile of an individual. Data linking home blood pressure monitors and home glucose sensors to dramatically improved outcomes for patients with systemic hypertension and diabetes and will be reviewed as they pertain to the question of whether ambulatory tonometry is positioned to do the same for glaucoma management. Prospective randomized controlled studies are warranted to determine whether remote tonometry-based glaucoma management might reduce vision loss and improve patient outcomes.

6.
J Pharm Bioallied Sci ; 16(Suppl 3): S2069-S2071, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39346290

RESUMO

Objectives: This study aimed to assess the lip prints of Indian twins and non-twin siblings to evaluate the existence of heredity in the lip prints of these individuals. Materials and Methods: The study employed a blind, cross-sectional, quantitative approach with an inductive method and extensive direct observation. The sample consisted of 30 twins and 30 non-twin siblings, divided into three groups based on gender with 10 subjects in each subgroup. All participants were aged between 10 and 30 years and were instructed on the methods and techniques involved in the study. Results: The lip prints of participants were recorded using dark-colored lipstick, bond paper, cellophane tape, and a brush, and were examined for lip thickness measurement (in mm), classification of lip commissures, and assessment of groove patterns. The findings were then analyzed to determine the pattern of lip prints among twins and non-twin siblings. Conclusion: Cheiloscopy, the forensic investigation technique based on lip trace identification, could benefit from this study's findings as it explores the existence of heredity in lip prints of Indian twins and non-twin siblings.

7.
J Pharm Bioallied Sci ; 16(Suppl 3): S2962-S2964, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39346302

RESUMO

Mucoceles are the most common minor salivary gland disorder and represent the second most frequent benign soft tissue tumors of the oral cavity, following irritative fibroma. Various treatment modalities have been suggested for mucocele among which different types of lasers being the most recent and advanced. In the present case reports, diode laser was used for the excision of mucocele on the lower lip, and the advantages of it over the conventional scalpel method were minimal discomfort, bleeding, recurrence, and better compliance among patients.

8.
J Pharm Bioallied Sci ; 16(Suppl 3): S2972-S2974, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39346490

RESUMO

Lipoma is a painless soft tissue tumor of mesenchymal origin, which is a well-defined and slow-growing tissue. The occurrence of lipoma is rare in the oral cavity (1-4%); however, the frequency is much higher in the head and neck region. The lipoma is commonly present in the buccal mucosa, lips, tongue, palate, buccal sulcus, and floor of the mouth. Sometimes, the lipoma becomes large enough to cause difficulty in speech and mastication. The main treatment for lipoma is surgical excision.

10.
Commun Eng ; 3(1): 107, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39095532

RESUMO

Percutaneous renal biopsy is commonly used for kidney cancer diagnosis. However, the biopsy procedure remains challenging in sampling accuracy. Here we introduce a forward-viewing optical coherence tomography probe for differentiating tumor and normal tissues, aiming at precise biopsy guidance. Totally, ten human kidney samples, nine of which had malignant renal carcinoma and one had benign oncocytoma, were used for system evaluation. Based on their distinct imaging features, carcinoma could be efficiently distinguished from normal renal tissues. Additionally, oncocytoma could be differentiated from carcinoma. We developed convolutional neural networks for tissue recognition. Compared to the conventional attenuation coefficient method, convolutional neural network models provided more accurate carcinoma predictions. These models reached a tissue recognition accuracy of 99.1% on a hold-out set of four kidney samples. Furthermore, they could efficiently distinguish oncocytoma from carcinoma. In conclusion, our convolutional neural network-aided endoscopic imaging platform could enhance carcinoma diagnosis during percutaneous renal biopsy procedures.

11.
Urology ; 190: 56-62, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38852626

RESUMO

OBJECTIVE: To determine whether robotic-assisted radical cystectomy (RARC) with intracorporeal urinary diversion (ICUD) compared to open radical cystectomy (ORC) or RARC with extracorporeal urinary diversion (ECUD) would result in a decreased rate of surgical site complications. RARC has been shown to be non-inferior to ORC. Both RARC and ORC are complicated by a high rate of perioperative morbidity, including wound-related complications, which may be decreased by a robotic approach with intracorporeal diversion. METHODS: A retrospective review of our bladder cancer database for patients undergoing radical cystectomy from 2013-2021. Patients were stratified by surgical technique as RARC with ICUD vs ORC vs RARC with ECUD. Surgical site complications were measured at both 30- and 90-day intervals. RESULTS: Of the 269 patients, 127 (47.2%) had RARC with ICUD, 118 (43.7%) had ORC, and 24 (8.9%) had RARC with ECUD (mean ages 71.0, 69.5, and 67.5, respectively). A comparison of the 3 groups demonstrated statistical significance at both the 30-day (P <.001) and 90-day (P <.001) timeframes for total surgical site complications, with RARC with ICUD having the fewest amount of patients experiencing a surgical site complication (0.8%) followed by ORC (25.4%) and RARC with ECUD (29.2%). CONCLUSION: Overall, we observed lower surgical site complication rates among patients undergoing RARC with ICUD compared to patients who underwent ORC or RARC with ECUD. This study suggests that decreased surgical site complications may be one benefit of the minimally invasive approach, particularly in patients at high risk for surgical site complications after radical cystectomy.


Assuntos
Cistectomia , Procedimentos Cirúrgicos Robóticos , Neoplasias da Bexiga Urinária , Derivação Urinária , Humanos , Cistectomia/efeitos adversos , Cistectomia/métodos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Estudos Retrospectivos , Feminino , Idoso , Masculino , Neoplasias da Bexiga Urinária/cirurgia , Derivação Urinária/métodos , Derivação Urinária/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Pessoa de Meia-Idade
12.
Nat Hum Behav ; 8(7): 1403-1416, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38802539

RESUMO

Ventromedial prefrontal cortex (vmPFC) is vital for decision-making. Functional neuroimaging links vmPFC to processing rewards and effort, while parallel work suggests vmPFC involvement in prosocial behaviour. However, the necessity of vmPFC for these functions is unknown. Patients with rare focal vmPFC lesions (n = 25), patients with lesions elsewhere (n = 15) and healthy controls (n = 40) chose between rest and exerting effort to earn rewards for themselves or another person. vmPFC damage decreased prosociality across behavioural and computational measures. vmPFC patients earned less, discounted rewards by effort more, and exerted less force when another person benefited, compared to both control groups. Voxel-based lesion mapping revealed dissociations between vmPFC subregions. While medial damage led to antisocial behaviour, lateral damage increased prosocial behaviour relative to patients with damage elsewhere. vmPFC patients also showed reduced effort sensitivity overall, but reward sensitivity was limited to specific subregions. These results reveal multiple causal contributions of vmPFC to prosocial behaviour, effort and reward.


Assuntos
Motivação , Córtex Pré-Frontal , Recompensa , Humanos , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiopatologia , Córtex Pré-Frontal/fisiologia , Masculino , Motivação/fisiologia , Feminino , Adulto , Pessoa de Meia-Idade , Comportamento Social , Imageamento por Ressonância Magnética , Tomada de Decisões/fisiologia , Idoso
13.
NPJ Digit Med ; 7(1): 118, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714742

RESUMO

Automated online cognitive assessments are set to revolutionise clinical research and healthcare. However, their applicability for Parkinson's Disease (PD) and REM Sleep Behavioural Disorder (RBD), a strong PD precursor, is underexplored. Here, we developed an online battery to measure early cognitive changes in PD and RBD. Evaluating 19 candidate tasks showed significant global accuracy deficits in PD (0.65 SD, p = 0.003) and RBD (0.45 SD, p = 0.027), driven by memory, language, attention and executive underperformance, and global reaction time deficits in PD (0.61 SD, p = 0.001). We identified a brief 20-min battery that had sensitivity to deficits across these cognitive domains while being robust to the device used. This battery was more sensitive to early-stage and prodromal deficits than the supervised neuropsychological scales. It also diverged from those scales, capturing additional cognitive factors sensitive to PD and RBD. This technology offers an economical and scalable method for assessing these populations that can complement standard supervised practices.

14.
PLoS Comput Biol ; 20(4): e1011516, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38626219

RESUMO

When facing an unfamiliar environment, animals need to explore to gain new knowledge about which actions provide reward, but also put the newly acquired knowledge to use as quickly as possible. Optimal reinforcement learning strategies should therefore assess the uncertainties of these action-reward associations and utilise them to inform decision making. We propose a novel model whereby direct and indirect striatal pathways act together to estimate both the mean and variance of reward distributions, and mesolimbic dopaminergic neurons provide transient novelty signals, facilitating effective uncertainty-driven exploration. We utilised electrophysiological recording data to verify our model of the basal ganglia, and we fitted exploration strategies derived from the neural model to data from behavioural experiments. We also compared the performance of directed exploration strategies inspired by our basal ganglia model with other exploration algorithms including classic variants of upper confidence bound (UCB) strategy in simulation. The exploration strategies inspired by the basal ganglia model can achieve overall superior performance in simulation, and we found qualitatively similar results in fitting model to behavioural data compared with the fitting of more idealised normative models with less implementation level detail. Overall, our results suggest that transient dopamine levels in the basal ganglia that encode novelty could contribute to an uncertainty representation which efficiently drives exploration in reinforcement learning.


Assuntos
Gânglios da Base , Dopamina , Modelos Neurológicos , Recompensa , Dopamina/metabolismo , Dopamina/fisiologia , Incerteza , Animais , Gânglios da Base/fisiologia , Comportamento Exploratório/fisiologia , Reforço Psicológico , Neurônios Dopaminérgicos/fisiologia , Biologia Computacional , Simulação por Computador , Masculino , Algoritmos , Tomada de Decisões/fisiologia , Comportamento Animal/fisiologia , Ratos
15.
Front Neurol ; 15: 1363190, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38654735

RESUMO

Introduction: The pupillary light reflex (PLR) is the constriction of the pupil in response to light. The PLR in response to a pulse of light follows a complex waveform that can be characterized by several parameters. It is a sensitive marker of acute neurological deterioration, but is also sensitive to the background illumination in the environment in which it is measured. To detect a pathological change in the PLR, it is therefore necessary to separate the contributions of neuro-ophthalmic factors from ambient illumination. Illumination varies over several orders of magnitude and is difficult to control due to diurnal, seasonal, and location variations. Methods and results: We assessed the sensitivity of seven PLR parameters to differences in ambient light, using a smartphone-based pupillometer (AI Pupillometer, Solvemed Inc.). Nine subjects underwent 345 measurements in ambient conditions ranging from complete darkness (<5 lx) to bright lighting (≲10,000 lx). Lighting most strongly affected the initial pupil size, constriction amplitude, and velocity. Nonlinear models were fitted to find the correction function that maximally stabilized PLR parameters across different ambient light levels. Next, we demonstrated that the lighting-corrected parameters still discriminated reactive from unreactive pupils. Ten patients underwent PLR testing in an ophthalmology outpatient clinic setting following the administration of tropicamide eye drops, which rendered the pupils unreactive. The parameters corrected for lighting were combined as predictors in a machine learning model to produce a scalar value, the Pupil Reactivity (PuRe) score, which quantifies Pupil Reactivity on a scale 0-5 (0, non-reactive pupil; 0-3, abnormal/"sluggish" response; 3-5, normal/brisk response). The score discriminated unreactive pupils with 100% accuracy and was stable under changes in ambient illumination across four orders of magnitude. Discussion: This is the first time that a correction method has been proposed to effectively mitigate the confounding influence of ambient light on PLR measurements, which could improve the reliability of pupillometric parameters both in pre-hospital and inpatient care settings. In particular, the PuRe score offers a robust measure of Pupil Reactivity directly applicable to clinical practice. Importantly, the formulae behind the score are openly available for the benefit of the clinical research community.

16.
Nat Hum Behav ; 8(7): 1351-1365, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38632389

RESUMO

When striking a balance between commitment to a goal and flexibility in the face of better options, people often demonstrate strong goal perseveration. Here, using functional MRI (n = 30) and lesion patient (n = 26) studies, we argue that the ventromedial prefrontal cortex (vmPFC) drives goal commitment linked to changes in goal-directed selective attention. Participants performed an incremental goal pursuit task involving sequential decisions between persisting with a goal versus abandoning progress for better alternative options. Individuals with stronger goal perseveration showed higher goal-directed attention in an interleaved attention task. Increasing goal-directed attention also affected abandonment decisions: while pursuing a goal, people lost their sensitivity to valuable alternative goals while remaining more sensitive to changes in the current goal. In a healthy population, individual differences in both commitment biases and goal-oriented attention were predicted by baseline goal-related activity in the vmPFC. Among lesion patients, vmPFC damage reduced goal commitment, leading to a performance benefit.


Assuntos
Atenção , Objetivos , Imageamento por Ressonância Magnética , Córtex Pré-Frontal , Humanos , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Atenção/fisiologia , Masculino , Feminino , Adulto , Adulto Jovem , Pessoa de Meia-Idade , Tomada de Decisões/fisiologia
17.
Nat Hum Behav ; 8(7): 1366-1382, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38684870

RESUMO

The role of the hippocampus in decision-making is beginning to be more understood. Because of its prospective and inferential functions, we hypothesized that it might be required specifically when decisions involve the evaluation of uncertain values. A group of individuals with autoimmune limbic encephalitis-a condition known to focally affect the hippocampus-were tested on how they evaluate reward against uncertainty compared to reward against another key attribute: physical effort. Across four experiments requiring participants to make trade-offs between reward, uncertainty and effort, patients with acute limbic encephalitis demonstrated blunted sensitivity to reward and effort whenever uncertainty was considered, despite demonstrating intact uncertainty sensitivity. By contrast, the valuation of these two attributes (reward and effort) was intact on uncertainty-free tasks. Reduced sensitivity to changes in reward under uncertainty correlated with the severity of hippocampal damage. Together, these findings provide evidence for a context-sensitive role of the hippocampus in value-based decision-making, apparent specifically under conditions of uncertainty.


Assuntos
Tomada de Decisões , Hipocampo , Recompensa , Humanos , Hipocampo/fisiopatologia , Incerteza , Tomada de Decisões/fisiologia , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Idoso , Imageamento por Ressonância Magnética
18.
Psychopharmacology (Berl) ; 241(7): 1365-1375, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38494550

RESUMO

Motivation allows us to energise actions when we expect reward and is reduced in depression. This effect, termed motivational vigour, has been proposed to rely on central dopamine, with dopaminergic agents showing promise in the treatment of depression. This suggests that dopaminergic agents might act to reduce depression by increasing the effects of reward or by helping energise actions. The aim of the current study was to investigate whether the dopamine agonist pramipexole enhanced motivational vigour during a rewarded saccade task. In addition, we asked whether the effects of pramipexole on vigour differ between reward contingent on performance and guaranteed reward. Healthy adult participants were randomised to receive either pramipexole (n = 19) or placebo (controls n = 18) for 18 days. The vigour of saccades was measured twice, once before the administration of study medication (Time 1) and after taking it for 12-15 days (Time 2). To separate motivation by contingency vs. reward, saccadic vigour was separately measured when (1) rewards were contingent on performance (2) delivered randomly with matched frequency, (3) when reward was guaranteed, (4) when reward was not present at all. Motivation increased response vigour, as expected. Relative to placebo, pramipexole also increased response vigour. However, there was no interaction, meaning that the effects of reward were not modulated by drug, and there was no differential drug effect on contingent vs. guaranteed rewards. The effect of pramipexole on vigour could not be explained by a speed/accuracy trade-off, nor by autonomic arousal as indexed by pupillary dilation. Chronic D2 stimulation increases general vigour, energising movements in healthy adults irrespective of extrinsic reward.


Assuntos
Agonistas de Dopamina , Motivação , Pramipexol , Recompensa , Movimentos Sacádicos , Humanos , Pramipexol/farmacologia , Pramipexol/administração & dosagem , Motivação/efeitos dos fármacos , Movimentos Sacádicos/efeitos dos fármacos , Masculino , Adulto , Feminino , Agonistas de Dopamina/farmacologia , Agonistas de Dopamina/administração & dosagem , Adulto Jovem , Método Duplo-Cego , Benzotiazóis/farmacologia , Benzotiazóis/administração & dosagem , Desempenho Psicomotor/efeitos dos fármacos
19.
EClinicalMedicine ; 69: 102437, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38544796

RESUMO

Background: Autoimmune limbic encephalitis (ALE) is a neurological disease characterised by inflammation of the limbic regions of the brain, mediated by pathogenic autoantibodies. Because cognitive deficits persist following acute treatment of ALE, the accurate assessment of long-term cognitive outcomes is important for clinical assessments and trials. However, evaluating cognition is costly and an unmet need exists for validated digital methods. Methods: In this cross-sectional validation study, we investigated whether a remote digital platform could identify previously characterised cognitive impairments in patients with chronic ALE and whether digital metrics would correlate with standard neuropsychological assessment and hippocampal volume. Patients with ALE who had a chronic and stable presentation and received a clinical diagnosis of ALE were recruited for this study. The cognitive performance of 21 patients with ALE and 54 age-matched healthy controls - enrolled via the University of Oxford (UK) Cognitive Neurology Lab testing programme - was assessed with a battery of 12 cognitive tasks from the Cognitron online platform. The platform was optimised with National Institute for Health and Care Research (NIHR) support to be deliverable remotely to elderly and patient groups. The primary outcome measure was behavioural performance and corresponding neuroimaging and neuropsychological assessment metrics. Findings: Between February 15, 2021, and April 21, 2022, 21 patients with ALE (mean age 63.01 years, 14 males) and 54 healthy controls (mean age 65.56 years, 23 males) completed the digital cognitive assessment. Patients with ALE performed significantly worse in memory, visuospatial abilities, executive function, and language. No impairments in digit & spatial span, target detection (attention) and emotion discrimination were observed. The global score on the online cognitive tasks correlated significantly with the established Addenbrooke's Cognitive Examination III (ACE) pen-and-paper test. Deficits in visuospatial processing and language were identified in ALE compared to controls using remote digital testing but not using the ACE, highlighting higher sensitivity of computerised testing to residual cognitive impairment. Finally, the hippocampal volumes of patients with ALE and healthy controls correlated with online cognitive scores. Interpretation: These findings demonstrate that subtle cognitive deficits in patients with chronic ALE, who often show full recovery in measures of disability and dependence on daily activities, are detectable using a remote online platform, which also relates to hippocampal atrophy. Such methods may facilitate the characterisation of cognitive profiles in complex neurological diseases. Future longitudinal studies designed to assess the utility of such digital methods for further clinical characterisation are needed. Funding: The Wellcome Trust, Medical Research Council, National Institute for Health Research, Rhodes Scholarship, and the Berrow Foundation Scholarship.

20.
J Biomol Struct Dyn ; 42(1): 483-494, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-36961221

RESUMO

Parkinson's disorder (PD) exacerbates neuronal degeneration of motor nerves, thereby effectuating uncoordinated movements and tremors. Aberrant alpha-synuclein (α-syn) is culpable of triggering PD, wherein cytotoxic amyloid aggregates of α-syn get deposited in motor neurons to instigate neuro-degeneration. Amyloid aggregates, typically rich in beta sheets are cardinal targets to mitigate their neurotoxic effects. In this analysis, owing to their interaction specificity, we formulated an efficacious tripeptide out of the aggregation-prone region of α-syn protein. With the help of a proficient computational pipeline, systematic peptide shortening and an adept molecular simulation platform, we formulated a tripeptide, VAV from α-syn structure based hexapeptide KISVRV. Indeed, the VAV tripeptide was able to effectively mitigate the α-syn amyloid fibrils' dynamic rate of beta-sheet formation. Additional trajectory analyses of the VAV- α-syn complex indicated that, upon its dynamic interaction, VAV efficiently altered the distinct pathogenic structural dynamics of α-syn, further advocating its potential in alleviating aberrant α-syn's amyloidogenic proclivities. Consistent findings from various computational analyses have led us to surmise that VAV could potentially re-alter the pathogenic conformational orientation of α-syn, essential to mitigate its cytotoxicity. Hence, VAV tripeptide could be an efficacious therapeutic candidate to efficiently ameliorate aberrant α-syn amyloid mediated neurotoxicity, eventually attenuating the nocuous effects of PD.Communicated by Ramaswamy H. Sarma.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Humanos , alfa-Sinucleína/química , Doença de Parkinson/metabolismo , Agregados Proteicos , Agregação Patológica de Proteínas/tratamento farmacológico , Amiloide/química , Computadores
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