scholarly journals Word-Embeddings and Grammar Features to Detect Language Disorders in Alzheimer’s Disease Patients

TecnoLógicas ◽  
2020 ◽  
Vol 23 (47) ◽  
pp. 63-75
Author(s):  
Juan S. Guerrero-Cristancho ◽  
Juan C. Vásquez-Correa ◽  
Juan R. Orozco-Arroyave
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Language Production ◽  
Neurodegenerative Disorder ◽  
Word Embedding ◽  
Normal Brain ◽  
Healthy Controls ◽  
Feature Sets ◽  
Early Fusion ◽  
Frequency Features

Alzheimer's Disease (AD) is a progressive neurodegenerative disorder that affects the language production and thinking capabilities of patients. The integrity of the brain is destroyed over time by interruptions in the interactions between neuron cells and associated cells required for normal brain functioning. AD comprises deterioration of the communicative skills, which is reflected in deficient speech that usually contains no coherent information, low density of ideas, and poor grammar. Additionally, patients exhibit difficulties to find appropriate words to structure sentences. Multiple ongoing studies aim to detect the disease considering the deterioration of language production in AD patients. Natural Language Processing techniques are employed to detect patterns that can be used to recognize the language impairments of patients. This paper covers advances in pattern recognition with the use of word-embedding and word-frequency features and a new approach with grammar features. We processed transcripts of 98 AD patients and 98 healthy controls in the Pitt Corpus of the Dementia-Bank database. A total of 1200 word-embedding features, 1408 Term Frequency—Inverse Document Frequency features, and 8 grammar features were extracted from the selected transcripts. Three models are proposed based on the separate extraction of such feature sets, and a fourth model is based on an early fusion strategy of the proposed feature sets. All the models were optimized following a Leave-One-Out cross validation strategy. Accuracies of up to 81.7 % were achieved using the early fusion of the three feature sets. Furthermore, we found that, with a small set of grammar features, accuracy values of up to 72.8 % were obtained. The results show that such features are suitable to effectively classify AD patients and healthy controls.

scholarly journals The Neuroprotective Effect of the Association of Aquaporin-4/Glutamate Transporter-1 against Alzheimer’s Disease

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Yu-Long Lan ◽  
Shuang Zou ◽  
Jian-Jiao Chen ◽  
Jie Zhao ◽  
Shao Li
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Neurodegenerative Disorder ◽  
Neuroprotective Effect ◽  
Ion Homeostasis ◽  
Water Channel ◽  
Glutamate Transporter ◽  
Aquaporin 4 ◽  
Normal Brain ◽  
Glutamate Transporter 1

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder that is characterized by memory loss and cognitive dysfunction. Aquaporin-4 (AQP4), which is primarily expressed in astrocytes, is the major water channel expressed in the central nervous system (CNS). This protein plays an important role in water and ion homeostasis in the normal brain and in various brain pathological conditions. Emerging evidence suggests that AQP4 deficiency impairs learning and memory and that this may be related to the expression of glutamate transporter-1 (GLT-1). Moreover, the colocalization of AQP4 and GLT-1 has long been studied in brain tissue; however, far less is known about the potential influence that the AQP4/GLT-1 complex may have on AD. Research on the functional interaction of AQP4 and GLT-1 has been demonstrated to be of great significance in the study of AD. Here, we review the interaction of AQP4 and GLT-1 in astrocytes, which might play a pivotal role in the regulation of distinct cellular responses that involve neuroprotection against AD. The association of AQP4 and GLT-1 could greatly supplement previous research regarding neuroprotection against AD.

scholarly journals Investigation of five polymorphic DNA markers associated with late onset Alzheimer disease

Genetika ◽  
2013 ◽  
Vol 45 (2) ◽  
pp. 503-514 ◽  
Author(s):  
Jalal Gharesouran ◽  
Maryam Rezazadeh ◽  
Mohaddes Mojtaba
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Dna Markers ◽  
Neurodegenerative Disorder ◽  
Late Onset ◽  
The Elderly ◽  
Healthy Controls ◽  
Genotype Frequencies ◽  
Significant Difference ◽  
And Control

Alzheimer's disease is a complex neurodegenerative disorder characterized by memory and cognitive impairment and is the leading cause of dementia in the elderly. The aim of our study was to examine the polymorphic DNA markers CCR2 (+190 G/A), CCR5?32, TNF-? (-308 G/A), TNF-? (-863 C/A) and CALHM1 (+394 C/T) to determine the relationship between these polymorphisms and the risk of late onset Alzheimer's disease in the population of Eastern Azerbaijan of Iran. A total of 160 patient samples and 163 healthy controls were genotyped by PCR-RFLP and the results confirmed using bidirectional sequencing. Statistical analysis of obtained data revealed non-significant difference between frequency of CCR5?32 in case and control groups. The same result was observed for TNF-? (-863 C/A) genotype and allele frequencies. Contrary to above results, significant differences were detected in frequency of TNF-? (-308 G/A) and CCR2-64I genotypes between the cases and healthy controls. A weak significant difference observed between allele and genotype frequencies of rs2986017 in CALHM1 (+394 C/T; P86L) in patient and control samples. It can be concluded that the T allele of P86L variant in CALHM1 & +190 G/A allele of CCR2 have a protective role against abnormal clinical features of Alzheimer's disease.

scholarly journals Decreased Blood Level of MFSD2a as a Potential Biomarker of Alzheimer’s Disease

2019 ◽  
Vol 21 (1) ◽  
pp. 70
Author(s):  
María Sánchez-Campillo ◽  
María José Ruiz-Pastor ◽  
Antonio Gázquez ◽  
Juan Marín-Muñoz ◽  
Fuensanta Noguera-Perea ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Whole Blood ◽  
Neurodegenerative Disorder ◽  
Major Facilitator Superfamily ◽  
Postmortem Brain ◽  
Healthy Controls ◽  
Potential Biomarker ◽  
Major Facilitator ◽  
First Time

The protein Major Facilitator Superfamily Domain containing 2A (MFSD2a) was recently described as the primary carrier for docosahexaenoic acid (DHA) into the brain. Alzheimer’s disease (AD) is a progressive neurodegenerative disorder characterized by lower DHA levels in blood lipids. The aim of this study was to investigate the expression of MFSD2a in the whole blood and brain as a potential biomarker of AD. Three groups were established: 38 healthy controls, 48 subjects with moderate AD (GDS4), and 47 with severe AD (GDS6). We analyzed postmortem brain samples from the hippocampus of 11 healthy controls and 11 severe AD patients. Fatty acid (FA) was determined in serum and brain by gas chromatography. Blood and brain MFSD2a protein expression was analyzed by Western blotting. We found a significant and progressive decline of MFSD2a levels in blood of AD patients (Control 0.83 ± 0.13, GDS4 0.72 ± 0.09, GDS6 0.48 ± 0.05*, p ˂ 0.01). We also corroborated a significant reduction of DHA and other n-3 long-chain polyunsaturated FA in serum of AD. No differences were found in MFSD2a expression or FA levels in brain of controls and AD subjects. MFSD2A carrier was analyzed in AD patients for the first time and the level of MFSD2a in the whole blood could be a potential biomarker of this disease.

Formation of paired helical filaments in Alzheimer's disease

1984 ◽  
Vol 42 ◽  
pp. 302-303
Author(s):  
J. Metuzals ◽  
D. F. Clapin ◽  
V. Montpetit
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Frontal Lobe ◽  
Giant Axon ◽  
Paired Helical Filaments ◽  
Normal Brain ◽  
Protein Assemblies ◽  
Electron Microscopic ◽  
Helical Symmetry ◽  
Structural Levels

Information on the conformation of paired helical filaments (PHF) and the neurofilamentous (NF) network is essential for an understanding of the mechanisms involved in the formation of the primary lesions of Alzheimer's disease (AD): tangles and plaques. The structural and chemical relationships between the NF and the PHF have to be clarified in order to discover the etiological factors of this disease. We are investigating by stereo electron microscopic and biochemical techniques frontal lobe biopsies from patients with AD and squid giant axon preparations. The helical nature of the lesion in AD is related to pathological alterations of basic properties of the nervous system due to the helical symmetry that exists at all hierarchic structural levels in the normal brain. Because of this helical symmetry of NF protein assemblies and PHF, the employment of structure reconstruction techniques to determine the conformation, particularly the handedness of these structures, is most promising. Figs. 1-3 are frontal lobe biopsies.

Auditory Dysfunction in Alzheimer's Disease

2010 ◽  
Vol 15 (1) ◽  
pp. 4-11 ◽  
Author(s):  
Sridhar Krishnamurti
Keyword(s):  
Alzheimer’S Disease ◽  
Older Adults ◽  
Alzheimer's Disease ◽  
Health Care ◽  
Care Setting ◽  
Neurodegenerative Disorder ◽  
Disease Process ◽  
Clinical Protocols ◽  
Speech Language Pathologist ◽  
Auditory Dysfunction

Alzheimer's disease is neurodegenerative disorder which affects a growing number of older adults every year. With an understanding of auditory dysfunction in Alzheimer's disease, the speech-language pathologist working in the health care setting can provide better service to these individuals. The pathophysiology of the disease process in Alzheimer's disease increases the likelihood of specific types of auditory deficits as opposed to others. This article will discuss the auditory deficits in Alzheimer's disease, their implications, and the value of clinical protocols for individuals with this disease.

Acetylcholinesterase Inhibitory Potential and Antioxidant Activities of Five Cultivars of Rosa Damascena Mill. From Isparta, Turkey

2020 ◽  
Vol 18 (4) ◽  
pp. 354-359
Author(s):  
Shirin Tarbiat ◽  
Azize Simay Türütoğlu ◽  
Merve Ekingen
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Free Radical ◽  
Neurodegenerative Disorder ◽  
Antioxidant Activities ◽  
Radical Scavenging ◽  
Acetylcholinesterase Activity ◽  
Rosa Damascena ◽  
Free Radical Damage

Alzheimer's disease is a neurodegenerative disorder characterized by memory loss and impairment of language. Alzheimer's disease is strongly associated with oxidative stress and impairment in the cholinergic pathway, which results in decreased levels of acetylcholine in certain areas of the brain. Hence, inhibition of acetylcholinesterase activity has been recognized as an acceptable treatment against Alzheimer's disease. Nature provides an array of bioactive compounds, which may protect against free radical damage and inhibit acetylcholinesterase activity. This study compares the in vitro antioxidant and anticholinesterase activities of hydroalcoholic extracts of five cultivars of Rosa Damascena Mill. petals (R. damascena 'Bulgarica', R. damascena 'Faik', R. damascena 'Iranica', R. damascena 'Complex-635' and R. damascena 'Complex-637') from Isparta, Turkey. The antioxidant activities of the hydroalcoholic extracts were tested for ferric ion reduction and DPPH radical scavenging activities. The anti-acetylcholinesterase activity was also evaluated. All rose cultivars showed a high potency for scavenging free radical and inhibiting acetylcholinesterase activity. There was a significant correlation between antioxidant and acetylcholinesterase inhibitory activity. Among cultivars, Complex-635 showed the highest inhibitory effect with an IC50 value of 3.92 µg/mL. Our results suggest that all these extracts may have the potential to treat Alzheimer's disease with Complex-635 showing more promise.

Repurposing Antihypertensive Drugs for the Management of Alzheimer’s Disease

2020 ◽  
Vol 27 ◽  
Author(s):  
Keng Yoon Yeong ◽  
Christine Law
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Risk Factor ◽  
Literature Review ◽  
Neurodegenerative Disorder ◽  
Antihypertensive Drugs ◽  
Future Prospects ◽  
Short Term

Alzheimer’s disease (AD) is a neurodegenerative disorder that has affected millions of people worldwide. However, currently there is no treatment to cure the disease. The AD drugs available in the market only manage the disease symptomatically and the effects are usually short-term. Thus, there is a need to look at alternatives AD therapies. Mid-life hypertension has not only been recognised as a risk factor for AD, but its relation with AD has also been well established. Thus, antihypertensives are postulated to be beneficial in managing AD. This literature review aims to shed some light on the potential of repurposing antihypertensives to treat AD, considering recent updates. Four classes of antihypertensives, as well as their potential limitations and future prospects in being utilised as AD therapeutics are discussed in this review.

Neuroprotective Effects of Ellagic Acid in Alzheimer's Disease: Focus on Underlying Molecular Mechanisms of Therapeutic Potential

2020 ◽  
Vol 26 ◽  
Author(s):  
Nimra Javaid ◽  
Muhammad Ajmal Shah ◽  
Azhar Rasul ◽  
Zunera Chauhdary ◽  
Uzma Saleem ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Ellagic Acid ◽  
Molecular Mechanisms ◽  
Neurodegenerative Disorder ◽  
Therapeutic Potential ◽  
Neuronal Cell Death ◽  
Neuronal Cell ◽  
Acetylcholinesterase Activity ◽  
Neuroprotective Effects

: Neurodegeneration is a multifactorial process involved the different cytotoxic pathways that lead towards neuronal cell death. Alzheimer’s disease (AD) is a persistent neurodegenerative disorder that normally has a steady onset yet later on it worsens. The documented evidence of AD neuropathology manifested the neuro-inflammation, increased reactive oxygen, nitrogen species and decreased antioxidant protective process; mitochondrial dysfunction as well as increased level of acetylcholinesterase activity. Moreover, enhanced action of proteins leads towards neural apoptosis which have a vital role in the degeneration of neurons. The inability of commercial therapeutic options to treat AD with targeting single mechanism leads the attraction towards organic drugs. Ellagic acid is a dimer of gallic acid, latest studies expressed that ellagic acid can initiate the numerous cell signaling transmission and decrease the progression of disorders, involved in the degeneration of neurons. The influential property of ellagic acid to protect the neurons in neurodegenerative disorders is due to its antioxidant effect, iron chelating and mitochondrial protective effect. The main goal of this review is to critically analyze the molecular mode of action of ellagic acid against neurodegeneration.

Electromagnetic field in Alzheimer’s disease: a literature review of recent preclinical and clinical studies

2020 ◽  
Vol 17 ◽  
Author(s):  
Reem Habib Mohamad Ali Ahmad ◽  
Marc Fakhoury ◽  
Nada Lawand
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Neurodegenerative Disorder ◽  
In Vivo Studies ◽  
Key Factors ◽  
Potential Benefits ◽  
Preclinical And Clinical Studies ◽  
The Brain

: Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by the progressive loss of neurons leading to cognitive and memory decay. The main signs of AD include the irregular extracellular accumulation of amyloidbeta (Aβ) protein in the brain and the hyper-phosphorylation of tau protein inside neurons. Changes in Aβ expression or aggregation are considered key factors in the pathophysiology of sporadic and early-onset AD and correlate with the cognitive decline seen in patients with AD. Despite decades of research, current approaches in the treatment of AD are only symptomatic in nature and are not effective in slowing or reversing the course of the disease. Encouragingly, recent evidence revealed that exposure to electromagnetic fields (EMF) can delay the development of AD and improve memory. This review paper discusses findings from in vitro and in vivo studies that investigate the link between EMF and AD at the cellular and behavioural level, and highlights the potential benefits of EMF as an innovative approach for the treatment of AD.

Microglia in Alzheimer’s Disease

2020 ◽  
Vol 17 (1) ◽  
pp. 29-43 ◽  
Author(s):  
Patrick Süß ◽  
Johannes C.M. Schlachetzki
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Neurodegenerative Disorder ◽  
Current Knowledge ◽  
Imaging Techniques ◽  
Amyloid Β ◽  
Disease Stage ◽  
Disease Modifying Therapy ◽  
Transcriptomic Signature

: Alzheimer’s Disease (AD) is the most frequent neurodegenerative disorder. Although proteinaceous aggregates of extracellular Amyloid-β (Aβ) and intracellular hyperphosphorylated microtubule- associated tau have long been identified as characteristic neuropathological hallmarks of AD, a disease- modifying therapy against these targets has not been successful. An emerging concept is that microglia, the innate immune cells of the brain, are major players in AD pathogenesis. Microglia are longlived tissue-resident professional phagocytes that survey and rapidly respond to changes in their microenvironment. Subpopulations of microglia cluster around Aβ plaques and adopt a transcriptomic signature specifically linked to neurodegeneration. A plethora of molecules and pathways associated with microglia function and dysfunction has been identified as important players in mediating neurodegeneration. However, whether microglia exert either beneficial or detrimental effects in AD pathology may depend on the disease stage. : In this review, we summarize the current knowledge about the stage-dependent role of microglia in AD, including recent insights from genetic and gene expression profiling studies as well as novel imaging techniques focusing on microglia in human AD pathology and AD mouse models.

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