scholarly journals Down syndrome detection using modified adaboost algorithm

Author(s):  
Vincy Devi V. K ◽  
Rajesh R.

In human body genetic codes are stored in the genes. All of our inherited traits are associated with these genes and are grouped as structures generally called chromosomes. In typical cases, each cell consists of 23 pairs of chromosomes, out of which each parent contributes half. But if a person has a partial or full copy of chromosome 21, the situation is called Down syndrome. It results in intellectual disability, reading impairment, developmental delay, and other medical abnormalities. There is no specific treatment for Down syndrome. Thus, early detection and screening of this disability are the best styles for down syndrome prevention. In this work, recognition of Down syndrome utilizes a set of facial expression images. Solid geometric descriptor is employed for extracting the facial features from the image set. An AdaBoost method is practiced to gather the required data sets and for the categorization. The extracted information is then assigned and used to instruct the Neural Network using Backpropagation algorithm. This work recorded that the presented model meets the requirement with 98.67% accuracy.

2019 ◽  
Vol 7 (1) ◽  
pp. 1-5
Author(s):  
Mohammad Amin Joshaghanian ◽  
Sassan Mohammadi ◽  
Zohreh Gholizadeh Ghozloujeh ◽  
Mehrdad Farahani ◽  
Kurosh Mojtabavi

Down syndrome (DS) is caused by complete or segmental chromosome 21 trisomy that results in neurodegeneration and progressive intellectual disability. Abnormal function in the prefrontal cortex, cerebellum, and hippocampus are the main reasons for cognitive deficits in DS that result in impaired cognitive function, delayed speech and language, learning and memory disability, and behavioral and emotional disorders. There is no specific treatment for DS, and our understanding of the mechanisms of the disorder is incomplete and causes to hamper the development of effective therapies regarding the development of neuropathology and memory loss in DS. Here, we review the literature on cognitive functioning, unique characteristics, environmental considerations, and recent findings on Alzheimer’s disease in DS.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Chinmay P. Swami ◽  
Nicholas Lenhard ◽  
Jiyeon Kang

AbstractProsthetic arms can significantly increase the upper limb function of individuals with upper limb loss, however despite the development of various multi-DoF prosthetic arms the rate of prosthesis abandonment is still high. One of the major challenges is to design a multi-DoF controller that has high precision, robustness, and intuitiveness for daily use. The present study demonstrates a novel framework for developing a controller leveraging machine learning algorithms and movement synergies to implement natural control of a 2-DoF prosthetic wrist for activities of daily living (ADL). The data was collected during ADL tasks of ten individuals with a wrist brace emulating the absence of wrist function. Using this data, the neural network classifies the movement and then random forest regression computes the desired velocity of the prosthetic wrist. The models were trained/tested with ADLs where their robustness was tested using cross-validation and holdout data sets. The proposed framework demonstrated high accuracy (F-1 score of 99% for the classifier and Pearson’s correlation of 0.98 for the regression). Additionally, the interpretable nature of random forest regression was used to verify the targeted movement synergies. The present work provides a novel and effective framework to develop an intuitive control for multi-DoF prosthetic devices.


2007 ◽  
Vol 7 (3) ◽  
pp. 215-218 ◽  
Author(s):  
Frenny J Sheth ◽  
Uppala Radhakrishna ◽  
Michael A Morris ◽  
Jean-Louis Blouin ◽  
Jayesh J Sheth ◽  
...  

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Chunyan Jin ◽  
Zhiping Gu ◽  
Xiaohan Jiang ◽  
Pei Yu ◽  
Tianhui Xu

Abstract Background Down syndrome is characterized by trisomy 21 or partial duplication of chromosome 21. Extensive studies have focused on the identification of the Down Syndrome Critical Region (DSCR). We aim to provide evidence that duplication of 21q21.1-q21.2 should not be included in the DSCR and it has no clinical consequences on the phenotype. Case presentation Because serological screening was not performed at the appropriate gestational age, noninvasive prenatal testing (NIPT) analysis was performed for a pregnant woman with normal prenatal examinations at 22 weeks of gestation. The NIPT results revealed a 5.8 Mb maternally inherited duplication of 21q21.1-q21.2. To assess whether the fetus also carried this duplication, ultrasound-guided amniocentesis was conducted, and the result of chromosomal microarray analysis (CMA) with amniotic fluid showed a 6.7 Mb duplication of 21q21.1-q21.2 (ranging from position 18,981,715 to 25,707,009). This partial duplication of 21q21.1-q21.2 in the fetus was maternally inherited. After genetic counseling, the pregnant woman and her family decided to continue the pregnancy. Conclusion Our case clearly indicates that 21q21.1-q21.2 duplication is not included in the DSCR and most likely has no clinical consequences on phenotype.


Biomolecules ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 266
Author(s):  
Chiara Lanzillotta ◽  
Fabio Di Domenico

Down syndrome (DS) is the most common genomic disorder characterized by the increased incidence of developing early Alzheimer’s disease (AD). In DS, the triplication of genes on chromosome 21 is intimately associated with the increase of AD pathological hallmarks and with the development of brain redox imbalance and aberrant proteostasis. Increasing evidence has recently shown that oxidative stress (OS), associated with mitochondrial dysfunction and with the failure of antioxidant responses (e.g., SOD1 and Nrf2), is an early signature of DS, promoting protein oxidation and the formation of toxic protein aggregates. In turn, systems involved in the surveillance of protein synthesis/folding/degradation mechanisms, such as the integrated stress response (ISR), the unfolded stress response (UPR), and autophagy, are impaired in DS, thus exacerbating brain damage. A number of pre-clinical and clinical studies have been applied to the context of DS with the aim of rescuing redox balance and proteostasis by boosting the antioxidant response and/or inducing the mechanisms of protein re-folding and clearance, and at final of reducing cognitive decline. So far, such therapeutic approaches demonstrated their efficacy in reverting several aspects of DS phenotype in murine models, however, additional studies aimed to translate these approaches in clinical practice are still needed.


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Benjamin I. Laufer ◽  
J. Antonio Gomez ◽  
Julia M. Jianu ◽  
Janine M. LaSalle

Abstract Background Down syndrome (DS) is characterized by a genome-wide profile of differential DNA methylation that is skewed towards hypermethylation in most tissues, including brain, and includes pan-tissue differential methylation. The molecular mechanisms involve the overexpression of genes related to DNA methylation on chromosome 21. Here, we stably overexpressed the chromosome 21 gene DNA methyltransferase 3L (DNMT3L) in the human SH-SY5Y neuroblastoma cell line and assayed DNA methylation at over 26 million CpGs by whole genome bisulfite sequencing (WGBS) at three different developmental phases (undifferentiated, differentiating, and differentiated). Results DNMT3L overexpression resulted in global CpG and CpG island hypermethylation as well as thousands of differentially methylated regions (DMRs). The DNMT3L DMRs were skewed towards hypermethylation and mapped to genes involved in neurodevelopment, cellular signaling, and gene regulation. Consensus DNMT3L DMRs showed that cell lines clustered by genotype and then differentiation phase, demonstrating sets of common genes affected across neuronal differentiation. The hypermethylated DNMT3L DMRs from all pairwise comparisons were enriched for regions of bivalent chromatin marked by H3K4me3 as well as differentially methylated sites from previous DS studies of diverse tissues. In contrast, the hypomethylated DNMT3L DMRs from all pairwise comparisons displayed a tissue-specific profile enriched for regions of heterochromatin marked by H3K9me3 during embryonic development. Conclusions Taken together, these results support a mechanism whereby regions of bivalent chromatin that lose H3K4me3 during neuronal differentiation are targeted by excess DNMT3L and become hypermethylated. Overall, these findings demonstrate that DNMT3L overexpression during neurodevelopment recreates a facet of the genome-wide DS DNA methylation signature by targeting known genes and gene clusters that display pan-tissue differential methylation in DS.


2021 ◽  
pp. 1-9
Author(s):  
Sushil Kumar Jaiswal ◽  
Ashok Kumar ◽  
Amit Kumar Rai

Down Syndrome (DS) caused by trisomy 21 results in various congenital and developmental complications in children. It is crucial to cytogenetically diagnose the DS cases early for their proper health management and to reduce the risk of further DS childbirths in mothers. In this study, we performed a cytogenetic analysis of 436 suspected DS cases using karyotyping and fluorescent in situ hybridization. We detected free trisomies (95.3%), robertsonian translocations (2.4%), isochromosomes (0.6%), and mosaics (1.2%). We observed a slightly higher incidence of DS childbirth in younger mothers compared to mothers with advanced age. We compared the somatic aneuploidy in peripheral blood of mothers having DS children (MDS) and control mothers (CM) to identify biomarkers for predicting the risk for DS childbirths. No significant difference was observed. After induced demethylation in peripheral blood cells, we did not observe a significant difference in the frequency of aneuploidy between MDS and CM. In conclusion, free trisomy 21 is the most common type of chromosomal abnormality in DS. A small number of DS cases have translocations and mosaicism of chromosome 21. Additionally, somatic aneuploidy in the peripheral blood from the mother is not an effective marker to predict DS childbirths.


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