A Novel Approach for Cognitive Clustering of Parkinsonisms through Affinity Propagation

Algorithms ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 49
Author(s):  
Alessia Sarica ◽  
Maria Grazia Vaccaro ◽  
Andrea Quattrone ◽  
Aldo Quattrone
Keyword(s):  
Cognitive Impairment ◽  
Cognitive Performance ◽  
A Priori ◽  
Affinity Propagation ◽  
Cognitive Profiles ◽  
Regression Residuals ◽  
Novel Approach ◽  
Healthy Control ◽  
Novel Method ◽  
Traditional Approaches

Cluster analysis is widely applied in the neuropsychological field for exploring patterns in cognitive profiles, but traditional hierarchical and non-hierarchical approaches could be often poorly effective or even inapplicable on certain type of data. Moreover, these traditional approaches need the initial specification of the number of clusters, based on a priori knowledge not always owned. For this reason, we proposed a novel method for cognitive clustering through the affinity propagation (AP) algorithm. In particular, we applied the AP clustering on the regression residuals of the Mini Mental State Examination scores—a commonly used screening tool for cognitive impairment—of a cohort of 49 Parkinson’s disease, 48 Progressive Supranuclear Palsy and 44 healthy control participants. We found four clusters, where two clusters (68 and 30 participants) showed almost intact cognitive performance, one cluster had a moderate cognitive impairment (34 participants), and the last cluster had a more extensive cognitive deficit (8 participants). The findings showed, for the first time, an intra- and inter-diagnostic heterogeneity in the cognitive profile of Parkinsonisms patients. Our novel method of unsupervised learning could represent a reliable tool for supporting the neuropsychologists in understanding the natural structure of the cognitive performance in the neurodegenerative diseases.

Multiscale Temporal and Spatial Estimation of the b-Value

2021 ◽  
Author(s):  
Rubén García-Hernández ◽  
Luca D’Auria ◽  
José Barrancos ◽  
Germán D. Padilla ◽  
Nemesio M. Pérez
Keyword(s):  
Spatial Scales ◽  
A Priori ◽  
Central Italy ◽  
B Value ◽  
Novel Approach ◽  
Temporal Estimation ◽  
Temporal And Spatial ◽  
Traditional Approaches ◽  
Tridimensional Mapping ◽  
Marked Drop

Abstract The estimation of the b-value of the Gutenberg–Richter law is of great importance in different seismological applications. However, its estimate is strongly dependent upon selecting a proper temporal and spatial scale, due to the multiscale nature of the seismicity. For this reason, we propose a novel approach (MUltiscale Spatial and Temporal estimation of the B-value [MUST-B]), which allows consistent estimation of the b-value, avoiding subjective “a priori” choices, by considering simultaneously different temporal or spatial scales. A reliable appraisal of the b-value is obtained by applying a robust median over the estimates computed over all the considered scales. We validate the method using a synthetic dataset, showing its superior performances, compared to traditional approaches, in detecting sharp changes in the b-value as well as inconsistently mapping it for highly heterogeneous catalogs. We apply MUST-B to study the temporal and spatial variations of the b-value during the complex 2016–2017 seismic sequence in central Italy, revealing various interesting patterns. In particular, we observe a marked drop of the b-value after the Accumoli (24 August 2016 M 6.0) mainshock. The drop is also observed when realizing a tridimensional mapping of the b-values, showing the drop occurs mainly in the proximity of major earthquake hypocenters. In accordance with previous studies, we interpret these variations as the effect of the release of crustal fluids following the major earthquakes. We maintain that MUST-B can also be applied to other contexts, such as volcanic and induced seismicity, because of its capacity of dealing consistently with highly heterogeneous seismicity patterns.

Analysis of Functional and Cognitive Impairment in Institutionalized Individuals with Movement Disorders

2019 ◽  
Vol 19 (7) ◽  
pp. 1022-1031 ◽  
Author(s):  
Paula D. Cebrián ◽  
Omar Cauli
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Cognitive Impairment ◽  
Activities Of Daily Living ◽  
Cognitive Performance ◽  
Functional Impairment ◽  
Movement Disorders ◽  
Neurological Disorders ◽  
Daily Living ◽  
Severe Cognitive Impairment

Background: Many neurological disorders lead to institutionalization and can be accompanied in their advanced stages by functional impairment, and progressive loss of mobility, and cognitive alterations. Objective: We analyzed the relationship between functional impairment and cognitive performance and its related subdomains in individuals with Parkinson’s disease, Alzheimer’s disease accompanied by motor dysfunction, and with other neurological disorders characterized by both motor and cognitive problems. Methods: All participants lived in nursing homes (Valencia, Spain) and underwent cognitive evaluation with the Mini-Mental State Examination; functional assessment of independence in activities of daily living using the Barthel score and Katz index; and assessment of mobility with the elderly mobility scale. Results: The mean age of the subjects was 82.8 ± 0.6 years, 47% of the sample included individuals with Parkinson’s disease, and 48 % of the sample presented severe cognitive impairment. Direct significant relationships were found between the level of cognitive impairment and functional capacity (p < 0.01) and mobility (p < 0.05). Among the different domains, memory impairment was not associated with altered activities of daily living or mobility. The functional impairment and the risk of severe cognitive impairment were significantly (p<0.05) higher in female compared to male patients. Among comorbidities, overweight/obesity and diabetes were significantly (p < 0.05) associated with poor cognitive performance in those individuals with mild/moderate cognitive impairment. Conclusion: In institutionalized individuals with movement disorders there is an association between functional and cognitive impairment. Reduction of over-weight and proper control of diabetes may represent novel targets for improving cognitive function at such early stages.

scholarly journals A novel approach to the computation of one-loop three- and four-point functions: I. The real mass case

2019 ◽  
Vol 2019 (11) ◽  
Author(s):  
J Ph Guillet ◽  
E Pilon ◽  
Y Shimizu ◽  
M S Zidi
Keyword(s):  
Building Blocks ◽  
The Real ◽  
Alternative Method ◽  
Novel Approach ◽  
Reduction Methods ◽  
Real Mass ◽  
Novel Method ◽  
Algebraic Reduction ◽  
The One ◽  
Mass Case

Abstract This article is the first of a series of three presenting an alternative method of computing the one-loop scalar integrals. This novel method enjoys a couple of interesting features as compared with the method closely following ’t Hooft and Veltman adopted previously. It directly proceeds in terms of the quantities driving algebraic reduction methods. It applies to the three-point functions and, in a similar way, to the four-point functions. It also extends to complex masses without much complication. Lastly, it extends to kinematics more general than that of the physical, e.g., collider processes relevant at one loop. This last feature may be useful when considering the application of this method beyond one loop using generalized one-loop integrals as building blocks.

scholarly journals Cognitive Issues in Pediatric Multiple Sclerosis

2021 ◽  
Vol 11 (4) ◽  
pp. 442
Author(s):  
Emilio Portaccio ◽  
Ermelinda De Meo ◽  
Angelo Bellinvia ◽  
Maria Pia Amato
Keyword(s):  
Multiple Sclerosis ◽  
Cognitive Impairment ◽  
Cognitive Decline ◽  
Pediatric Patients ◽  
Leisure Activities ◽  
Disease Onset ◽  
Cognitive Profiles ◽  
Brain Growth ◽  
Network Activation ◽  
Definition Of

Multiple sclerosis (MS) is one of the leading causes of disability in young adults. The onset of MS during developmental age makes pediatric patients particularly susceptible to cognitive impairment, resulting from both disease-related damage and failure of age-expected brain growth. Despite different test batteries and definitions, cognitive impairment has been consistently reported in approximately one-third of pediatric patients with MS. However, the lack of a uniform definition of cognitive impairment and the adoption of different test batteries have led to divergent results in terms of cognitive domains more frequently affected across the cohorts explored. This heterogeneity has hampered large international collaborative studies. Moreover, research aimed at the identification of risk factors (e.g., demographic, clinical, and radiological features) or protective factors (e.g., cognitive reserve, leisure activities) for cognitive decline is still scanty. Mood disorders, such as depression and anxiety, can be detected in these patients alongside cognitive decline or in isolation, and can negatively affect quality of life scores as well as academic performances. By using MRI, cognitive impairment was attributed to damage to specific brain compartments as well as to abnormal network activation patterns. However, multimodal MRI studies are still needed in order to assess the contribution of each MRI metric to cognitive impairment. Importantly, longitudinal studies have recently demonstrated failure of age-expected brain growth and of white matter (WM) and gray matter (GM) maturation plays a relevant role in determining cognitive dysfunction, in addition to MS-related direct damage. Whether these growth retardations might result in specific cognitive profiles according to the age at disease onset has not been studied, yet. A better characterization of cognitive profiles in pediatric MS patients, as well as the definition of neuroanatomical substrates of cognitive impairment and their longitudinal evolution are needed to develop efficient therapeutic strategies against cognitive impairment in this patient population.

scholarly journals Using historical data to facilitate clinical prevention trials in Alzheimer disease? An analysis of longitudinal MCI (mild cognitive impairment) data sets

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Manfred Berres ◽  
Andreas U. Monsch ◽  
René Spiegel
Keyword(s):  
Cognitive Impairment ◽  
Mild Cognitive Impairment ◽  
Cognitive Performance ◽  
Placebo Treatment ◽  
Drug Trial ◽  
The Other ◽  
Data Sets ◽  
Control Groups ◽  
Community Needs ◽  
Clinical Prevention

Abstract Background The Placebo Group Simulation Approach (PGSA) aims at partially replacing randomized placebo-controlled trials (RPCTs), making use of data from historical control groups in order to decrease the needed number of study participants exposed to lengthy placebo treatment. PGSA algorithms to create virtual control groups were originally derived from mild cognitive impairment (MCI) data of the Alzheimer’s Disease Neuroimaging Initiative (ADNI) database. To produce more generalizable algorithms, we aimed to compile five different MCI databases in a heuristic manner to create a “standard control algorithm” for use in future clinical trials. Methods We compared data from two North American cohort studies (n=395 and 4328, respectively), one company-sponsored international clinical drug trial (n=831) and two convenience patient samples, one from Germany (n=726), and one from Switzerland (n=1558). Results Despite differences between the five MCI samples regarding inclusion and exclusion criteria, their baseline demographic and cognitive performance data varied less than expected. However, the five samples differed markedly with regard to their subsequent cognitive performance and clinical development: (1) MCI patients from the drug trial did not deteriorate on verbal fluency over 3 years, whereas patients in the other samples did; (2) relatively few patients from the drug trial progressed from MCI to dementia (about 10% after 4 years), in contrast to the other four samples with progression rates over 30%. Conclusion Conventional MCI criteria were insufficient to allow for the creation of well-defined and internationally comparable samples of MCI patients. More recently published criteria for MCI or “MCI due to AD” are unlikely to remedy this situation. The Alzheimer scientific community needs to agree on a standard set of neuropsychological tests including appropriate selection criteria to make MCI a scientifically more useful concept. Patient data from different sources would then be comparable, and the scientific merits of algorithm-based study designs such as the PGSA could be properly assessed.

Cognitive profiles of children with autism spectrum disorder with parent-reported extraordinary talents and personal strengths

Autism ◽  
2021 ◽  
pp. 136236132110206
Author(s):  
Vanessa H Bal ◽  
Ellen Wilkinson ◽  
Megan Fok
Keyword(s):  
Cognitive Impairment ◽  
General Population ◽  
Standardized Tests ◽  
Autism Spectrum ◽  
Cognitive Test ◽  
Cognitive Profiles ◽  
Personal Strengths ◽  
Simons Simplex Collection ◽  
And Performance ◽  
The Relationship

It is essential to recognize the strengths and talents of autistic individuals. Previous studies of extraordinary talents (i.e. skills that stand out relative to the general population) have combined individuals with different skills (e.g. calendrical calculation, drawing) into one group. There has been limited investigation of talents in specific areas and even less consideration of personal strengths (i.e. skills that stand out relative to that person’s other abilities, but not the general population). We extend this literature by examining the relationship between parent-reported talents and strengths and performance on standardized cognitive tests in 1470 children (4–18 years) from the Simons Simplex Collection with autism and IQ above 70. Almost half (46%) had at least one parent-reported talent and an additional 23% without extraordinary talents had at least one personal strength. Children with parent-reported talents and strengths had different cognitive profiles than children with no reported skill in visuospatial, drawing, computation, or music. Those highlighted for their memory abilities had somewhat more even verbal and nonverbal abilities, relative to children whose memory was not emphasized as a special skill. These results emphasize the importance of exploring strengths separately by domain and a need for more research in this area. Lay abstract Previous research has suggested that focusing on impairments can be detrimental to the well-being of autistic individuals, yet little research has focused on strengths and positive qualities in autism. Some studies explored “savant skills” (herein referred to as “extraordinary talents”), that is, skills that stand out compared to the general population. These often group everyone who has a specific talent, rather than exploring subgroups with strengths in specific areas. There has been even less research focused on personal strengths (i.e. skills that stand out relative to the individual’s other abilities, but not the general population). To expand this research, we use a sample of 1470 children (ages 4–18 years) from the Simons Simplex Collection without cognitive impairment to examine the relationship between having a parent-reported skill in a specific area and performance on a standardized cognitive test. Almost half (46%) had at least one parent-reported talent and an additional 23% without extraordinary talents had at least one personal strength. Children with these parent-reported skills had different patterns of performance on these standardized tests than children without skills in that area (i.e. visuospatial, drawing, computation, reading, and memory). Specific skills in computation or reading were associated with higher overall performance on the standardized tests. These results emphasize the importance of considering strengths separately by area, rather than combining individuals with different types of strengths. The high number of children with skills in this study underscores the need for more research in this area, particularly using instruments focused on understanding the nuances of these strengths. It is important for future studies to consider these skills in children with cognitive impairment.

scholarly journals VAMP-2 is a surrogate cerebrospinal fluid marker of Alzheimer-related cognitive impairment in adults with Down syndrome

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Alberto Lleó ◽  
Maria Carmona-Iragui ◽  
Laura Videla ◽  
Susana Fernández ◽  
Bessy Benejam ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Down Syndrome ◽  
Cognitive Impairment ◽  
Episodic Memory ◽  
Cognitive Performance ◽  
Synaptic Proteins ◽  
Selected Reaction Monitoring ◽  
Synaptic Protein ◽  
Csf Levels ◽  
Syntaxin 1B

Abstract Background There is an urgent need for objective markers of Alzheimer’s disease (AD)-related cognitive impairment in people with Down syndrome (DS) to improve diagnosis, monitor disease progression, and assess response to disease-modifying therapies. Previously, GluA4 and neuronal pentraxin 2 (NPTX2) showed limited potential as cerebrospinal fluid (CSF) markers of cognitive impairment in adults with DS. Here, we compare the CSF profile of a panel of synaptic proteins (Calsyntenin-1, Neuroligin-2, Neurexin-2A, Neurexin-3A, Syntaxin-1B, Thy-1, VAMP-2) to that of NPTX2 and GluA4 in a large cohort of subjects with DS across the preclinical and clinical AD continuum and explore their correlation with cognitive impairment. Methods We quantified the synaptic panel proteins by selected reaction monitoring in CSF from 20 non-trisomic cognitively normal controls (mean age 44) and 80 adults with DS grouped according to clinical AD diagnosis (asymptomatic, prodromal AD or AD dementia). We used regression analyses to determine CSF changes across the AD continuum and explored correlations with age, global cognitive performance (CAMCOG), episodic memory (modified cued-recall test; mCRT) and CSF biomarkers, CSF Aβ42:40 ratio, CSF Aβ1-42, CSF p-tau, and CSF NFL. P values were adjusted for multiple testing. Results In adults with DS, VAMP-2 was the only synaptic protein to correlate with episodic memory (delayed recall adj.p = .04) and age (adj.p = .0008) and was the best correlate of CSF Aβ42:40 (adj.p = .0001), p-tau (adj.p < .0001), and NFL (adj.p < .0001). Compared to controls, mean VAMP-2 levels were lower in asymptomatic adults with DS only (adj.p = .02). CSF levels of Neurexin-3A, Thy-1, Neurexin-2A, Calysntenin-1, Neuroligin-2, GluA4, and Syntaxin-1B all strongly correlated with NPTX2 (p < .0001), which was the only synaptic protein to show reduced CSF levels in DS at all AD stages compared to controls (adj.p < .002). Conclusion These data show proof-of-concept for CSF VAMP-2 as a potential marker of synapse degeneration that correlates with CSF AD and axonal degeneration markers and cognitive performance.

scholarly journals The role of lipoprotein profile in depression and cognitive performance: a network analysis

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Qiu-fang Jia ◽  
Han-xue Yang ◽  
Nan-nan Zhuang ◽  
Xu-yuan Yin ◽  
Zhen-hua Zhu ◽  
...  
Keyword(s):  
Cognitive Impairment ◽  
Network Analysis ◽  
High Density Lipoprotein ◽  
Lipid Profile ◽  
Cognitive Performance ◽  
Serum Lipid ◽  
Density Lipoprotein ◽  
Lipoprotein Profile ◽  
Depressive State

AbstractLipid profile (total cholesterol and lipoprotein fractions) has been found to correlate with depression and cognitive impairment across the lifespan. However, the role of lipid levels in self-rated depressive state and cognitive impairment remains unclear. In this study, we examined the relationship between lipid profile (total cholesterol, triglycerides, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol) and cognition in adults with and without self-rated depression. Four hundred and thirty-eight healthy participants completed the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), the Self-Rating Depression Scale (SDS), and a serum lipoprotein test. Using multivariate ANOVA, partial correlation and network analysis, a network linking lipoprotein profile, depressive state and cognition was constructed. A significant difference in serum lipid profile between the high and low depressive groups was detected. Depressive state had a strong negative correlation with cognitive performance. Of the lipid profile, only high-density lipoprotein was positively correlated with depressive symptom severity, whereas the other three indices showed negative correlation with both depressive state and cognitive performance. Our results suggest that serum lipid profile may be directly linked to self-rated depression and cognitive performance. Further studies recruiting larger clinical samples are needed to elucidate the specific effect of lipoprotein on cognitive impairment in mood disorder.

scholarly journals Antiviral Resistance against Viral Mutation: Praxis and Policy for SARS-CoV-2

2021 ◽  
Vol 9 (1) ◽  
pp. 81-89
Author(s):  
Robert Penner
Keyword(s):  
Free Energy ◽  
Vaccine Development ◽  
A Priori ◽  
Structural Data ◽  
Medical Sciences ◽  
Spike Glycoprotein ◽  
Mutagenic Potential ◽  
Viral Mutation ◽  
Novel Method ◽  
Antiviral Targets

Abstract Tools developed by Moderna, BioNTech/Pfizer, and Oxford/Astrazeneca, among others, provide universal solutions to previously problematic aspects of drug or vaccine delivery, uptake and toxicity, portending new tools across the medical sciences. A novel method is presented based on estimating protein backbone free energy via geometry to predict effective antiviral targets, antigens and vaccine cargos that are resistant to viral mutation. This method is reviewed and reformulated in light of the recent proliferation of structural data on the SARS-CoV-2 spike glycoprotein and its mutations in multiple lineages. Key findings include: collections of mutagenic residues reoccur across strains, suggesting cooperative convergent evolution; most mutagenic residues do not participate in backbone hydrogen bonds; metastability of the glyco-protein limits the change of free energy through mutation thereby constraining selective pressure; and there are mRNA or virus-vector cargos targeting low free energy peptides proximal to conserved high free energy peptides providing specific recipes for vaccines with greater specificity than the full-spike approach. These results serve to limit peptides in the spike glycoprotein with high mutagenic potential and thereby provide a priori constraints on viral and attendant vaccine evolution. Scientific and regulatory challenges to nucleic acid therapeutic and vaccine development and deployment are finally discussed.

Effect of education on cognitive performance in patients with mild cognitive impairment

2021 ◽  
pp. 1-10
Author(s):  
Filipe Godinho ◽  
Carolina Maruta ◽  
Cláudia Borbinha ◽  
Isabel Pavão Martins
Keyword(s):  
Cognitive Impairment ◽  
Mild Cognitive Impairment ◽  
Cognitive Performance
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