Biology subjects

Sun, W.

Publications and source records attributed to Sun, W..

At least 253 records · Page 14Linked to original sources

bioRxiv2020

Newcastle disease virus (NDV) expressing the spike protein of SARS-CoV-2 as vaccine candidate

Due to the lack of protective immunity of humans towards the newly emerged SARS-CoV-2, this virus has caused a massive pandemic across the world resulting in hundreds of thousands of deaths. Thus, a vaccine is urgently needed to contain the spread of the virus. Here, we describe Newcastle disease virus (NDV) vector vaccines expressing the spike protein of SARS-CoV-2 in its wild type or a pre-fusion membrane anchored format. All described NDV vector vaccines grow to high titers in embryonated chicken eggs. In a proof of principle mouse study, we report that the NDV vector vaccines elicit high levels of antibodies that are neutralizing when the vaccine is given intramuscularly. Importantly, these COVID-19 vaccine candidates protect mice from a mouse-adapted SARS-CoV-2 challenge with no detectable viral titer and viral antigen in the lungs. Research in contextO_ST_ABSEvidence before this studyC_ST_ABSThe spike (S) protein of the SARS-CoV-2 is the major antigen that notably induces neutralizing antibodies to block viral entry. Many COVID-19 vaccines are under development, among them viral vectors expressing the S protein of SARS-CoV-2 exhibit many benefits. Viral vector vaccines have the potential of being used as both live or inactivated vaccines and they can induce Th1 and Th2-based immune responses following different immunization regimens. Additionally, viral vector vaccines can be handled under BSL-2 conditions and they grow to high titers in cell cultures or other species restricted-hosts. For a SARS-CoV-2 vaccine, several viral vectors are being tested, such as adenovirus, measles virus and Modified vaccinia Ankara. Added value of this studyThe NDV vector vaccine against SARS-CoV-2 described in this study has advantages similar to those of other viral vector vaccines. But the NDV vector can be amplified in embryonated chicken eggs, which allows for high yields and low costs per dose. Also, the NDV vector is not a human pathogen, therefore the delivery of the foreign antigen would not be compromised by any pre-existing immunity in humans. Finally, NDV has a very good safety record in humans, as it has been used in many oncolytic virus trials. This study provides an important option for a cost-effective SARS-CoV-2 vaccine. Implications of all the available evidenceThis study informs of the value of a viral vector vaccine against SARS-CoV-2. Specifically, for this NDV based SARS-CoV-2 vaccine, the existing egg-based influenza virus vaccine manufactures in the U.S. and worldwide would have the capacity to rapidly produce hundreds of millions of doses to mitigate the consequences of the ongoing COVID-19 pandemic.

microbiology↗

bioRxiv2020

Cross-talk between the methylerythritol phosphate and mevalonic acid pathways of isoprenoid biosynthesis in poplar

The isoprenoids found in plants are extremely important to survive with various human applications, such as flavoring, fragrance, dye, pharmaceuticals, and biomass used for biofuels. Methylerythritol phosphate (MEP) and mevalonic acid (MVA) pathways are critical in plants, responsible for isoprenoid biosynthesis. 1-deoxy-D-xylulose5-phosphate synthase (DXS) and 1-deoxy-D-xylulose5-phosphate reductoisomerase (DXR) catalyze the rate-limiting steps in the MEP pathway, while 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) catalyzes the rate-limiting step in the MVA pathway. Here, we showed while PtHMGR overexpressors (OEs) exhibited different MEP- and MVA-related gene expressions compared with non-transgenic poplars (NT), the PtDXR-OEs revealed upregulated MEP-related and downregulated MVA-related gene expressions. PtDXR and PtHMGR overexpressions caused changes in MVA-derived trans-zeatin-riboside, isopentenyl adenosine, castasterone, and 6-deoxocastasterone well as MEP-derived carotenoids and gibberellins. In PtHMGR-OEs, the accumulated geranyl diphosphate synthase (GPS) and geranyl pyrophosphate synthase (GPPS) transcript levels in the MEP pathway led to an accumulation of MEP-derived isoprenoids. In contrast, upregulation of farnesyl diphosphate synthase (FPS) expression in the MVA pathway contributed to increased levels of MVA-derived isoprenoids. In addition, PtHMGR-OEs increased MEP-related GPS and GPPS transcript levels, expanded MEP-derived isoprenoid levels, changed FPS transcript levels, and affected MVA-derived isoprenoid yields. These results demonstrate the contribution of MVA and MEP pathways regulating isoprenoid biosynthesis in poplars.

molecular biology↗

bioRxiv2020

Cell Type Aware analysis of RNA-seq data(CARseq) reveals difference and similarities ofthe molecular mechanisms of Schizophrenia andAutism

Most tissue samples are composed of different cell types. Differential expression analysis without accounting for cell type composition cannot separate the changes due to cell type composition or cell type-specific expression. We propose a computational framework to address these limitations: Cell Type Aware analysis of RNA-seq (CARseq). CARseq employs a negative binomial distribution that appropriately models the count data from RNA-seq experiments. Simulation studies show that CARseq has substantially higher power than a linear model-based approach and it also provides more accurate estimate of the rankings of differentially expressed genes. We have applied CARseq to compare gene expression of schizophrenia/autism subjects versus controls, and identified the cell types underlying the difference and similarities of these two neuron-developmental diseases. Our results are consistent with the results from differential expression analysis using single cell RNA-seq data.

bioinformatics↗

bioRxiv2020

CRISPR-Cas9 integrates exogeneous sorting new recombinant DNA in the model tree Populus trichocarpa

CRISPR-mediated genome editing has become a powerful tool for genetic modification of biological traits. However, developing an efficient, site-specific, gene knock-in system based on homology-directed DNA repair (HDR) remains a significant challenge in plants, especially in woody species like poplar. Here, we show that simultaneous inhibition of non-homologous end joining (NHEJ) recombination cofactor XRCC4 and overexpression of HDR enhancer factors CtIP and MRE11 can improve the HDR efficiency for gene knock-in. Using this approach, the BleoR gene was integrated onto the 3' end of the MKK2 MAP Kinase gene to generate a BleoR-MKK2 fusion protein. Based on exogenous BleoR expression, the HDR-mediated knock-in efficiency was up to [~]40-fold greater when using a XRCC4 silencing incorporated with a combination of CtIP and MRE11 overexpression compared to no HDR enhancement or NHEJ silencing. Furthermore, this corporation of HDR enhancer overexpression and NHEJ repression also resulted in 7-fold fewer CRISPR-induced Insertions and Deletions (InDels), resulting in no functional effects on MKK2-based salt stress responses in poplar. Therefore, this approach may be useful not only in poplar and plants or crops but also in mammalians for improving CRISPR-mediated gene knock-in efficiency.

plant biology↗

bioRxiv2020

Effect of hydrogen inhalation on IL-40 and SIgA in a Rat Model of Pulmonary Mucosal Immunity

Background Recently, some researchers have reported that PIgR expression is down-regulated in Chronic Obstructive Pulmonary Disease (COPD) and SIgA deficiency correlates with severity of airflow obstruction. What’ s more, some studies have demonstrated that 2 percent of hydrogen or hydrogen water is effective in treating and preventing various diseases.Objectives The aim of this study was to observe the effect of hydrogen on the expression of SIgA, PIgR, IL-4, IL-5, TGF-β1 and IL-40 in lung tissue of COPD rats, to study the relationship between lung pathology parameter and SIgA, PIgR, therefore we can understand the effect of hydrogen on the development of COPD by changing SIgA expression of airway mucosal in COPD rats.Methods A rat model of COPD was established by cigarette smoke exposure, and different concentrations of hydrogen were inhaled as intervention measures. After 4 months of cigarette smoke exposure, pathologic changes and airway wall remodeling of the lung were assessed by optical microscope. The protein expressions of SIgA, PIgR, IL-4, IL-5, TGF-β1 as well as IL-40 in the lung tissues were observed by immunohistochemistry or Western blot. The correlation between lung pathology parameter and the expression of SIgA, PIgR was analyzed. The correlation between SIgA and the expression of IL-4, IL-5, TGF-β1 and IL-40 was analyzed.Results The results showed that hydrogen inhalation significantly ameliorated lung pathology and airway wall remodeling, increased the protein expression of SIgA, PIgR, IL-4, IL-5, and IL-40, and reduced the protein expression of TGF-β1.Conclusions Inhalation of 22% and 41.6% hydrogen showed a better effect than inhalation of 2% hydrogen. Hydrogen inhalation can significantly improve the expression of SIgA on the mucosal surface of COPD rats, which may be one of the mechanisms which hydrogen works on COPD pathogenesis.View Full Text

immunology↗

bioRxiv2020

Abundance and nuclear antigen reactivity of intestinal and fecal Immunoglobulin A in lupus-prone mice at younger ages correlate with the onset of eventual systemic autoimmunity

Our recent studies, using (SWRxNZB)F1 (SNF1) mice, showed a potential contribution of the gut microbiota and pro-inflammatory immune responses of the gut mucosa to systemic autoimmunity in lupus. Here, using this mouse model, we determined the abundance and the nAg reactivity of IgA antibody produced in the intestine under lupus susceptibility. Intestinal lymphoid tissues from SNF1 mice, females particularly, showed significantly higher frequencies of nAg (dsDNA and nucleohistone) reactive IgA producing B cells compared to B6 females. Most importantly, younger age fecal IgA -abundance and - nAg reactivity of lupus-prone mice showed a positive correlation with eventual systemic autoimmunity and proteinuria onset. Depletion of gut microbiota in SNF1 mice resulted in the diminished production of IgA in the intestine and the nAg reactivity of these antibodies. Overall, these observations show that fecal IgA features, nuclear antigen reactivity particularly, at preclinical stages/in at-risk subjects could be predictive of autoimmune progression.Competing Interest StatementThe authors have declared no competing interest.AbbreviationsSLEsystemic lupus erythematosusSNF1 mice(SWRxNZB)-F1 micenAgnuclear antigenPPPeyers’ patchLPLamina PropriaSIsmall intestineGFgerm-freeSPFspecific pathogen freeTLRtoll-like receptorsAbxantibiotic cocktailMUSCMedical University of South CarolinaELISAEnzyme-linked immunosorbent assaydsDNAdouble stranded DNAView Full Text

immunology↗

bioRxiv2020

Population Bottlenecks and Intra-host Evolution during Human-to-Human Transmission of SARS-CoV-2Population Bottlenecks and Intra-host Evolution during Human-to-Human Transmission of SARS-CoV-2

The emergence of the novel human coronavirus, SARS-CoV-2, causes a global COVID-19 (coronavirus disease 2019) pandemic. Here, we have characterized and compared viral populations of SARS-CoV-2 among COVID-19 patients within and across households. Our work showed an active viral replication activity in the human respiratory tract and the co-existence of genetically distinct viruses within the same host. The inter-host comparison among viral populations further revealed a narrow transmission bottleneck between patients from the same households, suggesting a dominated role of stochastic dynamics in both inter-host and intra-host evolutions. Author summaryIn this study, we compared SARS-CoV-2 populations of 13 Chinese COVID-19 patients. Those viral populations contained a considerable proportion of viral sub-genomic messenger RNAs (sgmRNA), reflecting an active viral replication activity in the respiratory tract tissues. The comparison of 66 identified intra-host variants further showed a low viral genetic distance between intra-household patients and a narrow transmission bottleneck size. Despite the co-existence of genetically distinct viruses within the same host, most intra-host minor variants were not shared between transmission pairs, suggesting a dominated role of stochastic dynamics in both inter-host and intra-host evolutions. Furthermore, the narrow bottleneck and active viral activity in the respiratory tract show that the passage of a small number of virions can cause infection. Our data have therefore delivered a key genomic resource for the SARS-CoV-2 transmission research and enhanced our understanding of the evolutionary dynamics of SARS-CoV-2.

genetics↗

bioRxiv2020

A path towards SARS-CoV-2 attenuation: metabolic pressure on CTP synthesis rules the virus evolution

Fighting the COVID-19 epidemic summons deep understanding of the way SARS-CoV-2 taps into its host cell metabolic resources. We describe here the singular metabolic background that creates a bottleneck constraining coronaviruses to evolve towards likely attenuation in the long term. Cytidine triphosphate (CTP) is at the crossroad of the biosynthetic processes that allow the virus to multiply. This is because CTP is in demand for three essential steps. It is a building block of the virus genome, it is required for synthesis of the cytosine-based liponucleotide precursors of the viral envelope and, finally, it is a critical building block of the host transfer RNAs synthesis. The CCA 3-end of all the transfer RNAs required to translate the RNA genome and further transcripts into the proteins used to build active virus copies is not coded in the human genome. It must be synthesized de novo from CTP and ATP. Furthermore, intermediary metabolism is built on compulsory steps of synthesis and salvage of cytosine-based metabolites via uridine triphosphate (UTP) that keep limiting CTP availability. As a consequence, accidental replication errors tend to replace cytosine by uracil in the genome, unless recombination events allow the sequence to return to its ancestral sequences. We document some of the consequences of this situation in the function of viral proteins. We also highlight and provide a raison detre to viperin, an enzyme of innate antiviral immunity, which synthesizes 3-deoxy-3',4-didehydro-CTP (ddhCTP) as an extremely efficient antiviral nucleotide.

genomics↗

bioRxiv2020

Deep learning approach for automated cancer detection and tumor proportion score estimation of PD-L1 expression in lung adenocarcinoma

Background This study proposed a computational method to detect the cancer areas and calculate the tumor proportion score (TPS) of PD-L1 immunohistochemistry (IHC) expression for lung adenocarcinoma based on deep learning and transfer learning.Patients and methods PD-L1 22C3 and SP142 IHC slides of lung adenocarcinoma samples on digitized whole-slide images (WSI) database were employed. We build a deep convolutional neural network (DCNN) to automatically segment cancer regions. TPS was calculated based on segmented areas and then compared with the interpretations of pathologists.Results We trained a DCNN model based on 22C3 dataset and fine-tuned it with SP142 dataset. We obtain a robust performance on cancer region detection on both datasets, with a sensitivity of 93.36% (22C3) and 92.80% (SP142) and a specificity of 93.97% (22C3) and 89.25% (SP142). With all the coefficient of determinations larger than 0.9 and Fleiss’ and Cohen’s Kappa larger than 0.8 (between mean or median of pathologists and TPS calculated by our method), we also found out the strong correlation between the TPS estimated by our computational method and estimation from multiple pathologists’ interpretations of 22C3 and SP142 respectively.Conclusion We provide an AI method to efficiently predict cancer region and calculate TPS in PD-L1 IHC slide of lung adenocarcinoma on two different antibodies. It demonstrates the potential of using deep learning methods to conveniently access PD-L1 IHC status. In the future, we will further validate the AI tool for automated scoring PD-L1 in large volume samples.Competing Interest StatementThe authors have declared no competing interest.View Full Text

pathology↗

bioRxiv2020

Intra-host Variation and Evolutionary Dynamics of SARS-CoV-2 Population in COVID-19 Patients

As of middle May 2020, the causative agent of COVID-19, SARS-CoV-2, has infected over 4 million people with more than 300 thousand death as official reports1,2. The key to understanding the biology and virus-host interactions of SARS-CoV-2 requires the knowledge of mutation and evolution of this virus at both inter- and intra-host levels. However, despite quite a few polymorphic sites identified among SARS-CoV-2 populations, intra-host variant spectra and their evolutionary dynamics remain mostly unknown. Here, using deep sequencing data, we achieved and characterized consensus genomes and intra-host genomic variants from 32 serial samples collected from eight patients with COVID-19. The 32 consensus genomes revealed the coexistence of different genotypes within the same patient. We further identified 40 intra-host single nucleotide variants (iSNVs). Most (30/40) iSNVs presented in single patient, while ten iSNVs were found in at least two patients or identical to consensus variants. Comparison of allele frequencies of the iSNVs revealed genetic divergence between intra-host populations of the respiratory tract (RT) and gastrointestinal tract (GIT), mostly driven by bottleneck events among intra-host transmissions. Nonetheless, we observed a maintained viral genetic diversity within GIT, showing an increased population with accumulated mutations developed in the tissue-specific environments. The iSNVs identified here not only show spatial divergence of intra-host viral populations, but also provide new insights into the complex virus-host interactions.

genomics↗

bioRxiv2020

scConsensus: combining supervised and unsupervised clustering for cell type identification in single-cell RNA sequencing data

Clustering is a crucial step in the analysis of single-cell data. Clusters identified using unsupervised clustering are typically annotated to cell types based on differentially expressed genes. In contrast, supervised methods use a reference panel of labelled transcriptomes to guide both clustering and cell type identification. Supervised and unsupervised clustering strategies have their distinct advantages and limitations. Therefore, they can lead to different but often complementary clustering results. Hence, a consensus approach leveraging the merits of both clustering paradigms could result in a more accurate clustering and a more precise cell type annotation. We present O_SCPLOWSCC_SCPLOWCO_SCPLOWONSENSUSC_SCPLOW, an R framework for generating a consensus clustering by (i) integrating the results from both unsupervised and supervised approaches and (ii) refining the consensus clusters using differentially expressed (DE) genes. The value of our approach is demonstrated on several existing single-cell RNA sequencing datasets, including data from sorted PBMC sub-populations. O_SCPLOWSCC_SCPLOWCO_SCPLOWONSENSUSC_SCPLOW is freely available on GitHub at https://github.com/prabhakarlab/scConsensus.

bioinformatics↗

bioRxiv2020

The effects of YKL-40 on angiogenic potential of HUVECs are partly mediated by syndecan-4

ObjectiveYKL-40, a secreted glycoprotein, has a role in promoting tumor angiogenesis through syndecan-1 receptor. As one of the members of syndecans family, syndecan-4 is also an important mediator for tube formation. However, the effects of YKL-40 on migration and tube formation of human umbilical vein cells (HUVECs) mediated by syndecan-4 receptor are unknown. MethodsHUVECs were transfected with lentivirus encoding syndecan-4 short hairpin (sh) RNA (lenti-synd4 shRNA) and the efficiency of transfection was measured using reverse transcription quantitative real time polymerase chain reaction (qRT-PCR) and flow cytometry. The effects of recombinant protein of YKL-40 on migration and angiogenesis of HUVECs adjusted by syndecan-4 were determined by wound healing and tube formation assay. The expression of protein kinase C (PKC) and extracellular signal regulated kinases (ERKs) 1 and 2 (ERK1/2) in HUVECs was measured using western blotting. ResultsTransfection of lenti-synd4 shRNA significantly decreased the membrane protein expression of syndecan-4 in HUVECs. HUVECs transfected with lenti-synd4 shRNA remarkably inhibited the migration and tube formation of endothelial cells stimulated by recombinant protein of YKL-40. The levels of PKC and ratio of p-ERK1/2 to ERK1/2 in HUVECs were also down-regulated by silencing syndecan-4. ConclusionThe effects of YKL-40-induced on migration and tube formation of HUVECs may partly be inhibited by knock-downing syndecan-4 through suppressing PKC and ERK1/2 signaling pathways.

molecular biology↗

bioRxiv2020

Genomic Architecture of Cells in Tissues (GeACT): Study of Human Mid-gestation Fetus

By circumventing cellular heterogeneity, single cell omics have now been widely utilized for cell typing in human tissues, culminating with the undertaking of human cell atlas aimed at characterizing all human cell types. However, more important are the probing of gene regulatory networks, underlying chromatin architecture and critical transcription factors for each cell type. Here we report the Genomic Architecture of Cells in Tissues (GeACT), a comprehensive genomic data base that collectively address the above needs with the goal of understanding the functional genome in action. GeACT was made possible by our novel single-cell RNA-seq (MALBAC-DT) and ATAC-seq (METATAC) methods of high detectability and precision. We exemplified GeACT by first studying representative organs in human mid-gestation fetus. In particular, correlated gene modules (CGMs) are observed and found to be cell-type-dependent. We linked gene expression profiles to the underlying chromatin states, and found the key transcription factors for representative CGMs. HighlightsO_LIGenomic Architecture of Cells in Tissues (GeACT) data for human mid-gestation fetus C_LIO_LIDetermining correlated gene modules (CGMs) in different cell types by MALBAC-DT C_LIO_LIMeasuring chromatin open regions in single cells with high detectability by METATAC C_LIO_LIIntegrating transcriptomics and chromatin accessibility to reveal key TFs for a CGM C_LI

genomics↗

bioRxiv2020

Lectin-like Intestinal Defensin Inhibits 2019-nCoV Spike binding to ACE2

The burgeoning epidemic caused by novel coronavirus 2019 (2019-nCoV) is currently a global concern. Angiotensin-converting enzyme-2 (ACE2) is a receptor of 2019-nCoV spike 1 protein (S1) and mediates viral entry into host cells. Despite the abundance of ACE2 in small intestine, few digestive symptoms are observed in patients infected by 2019-nCoV. Herein, we investigated the interactions between ACE2 and human defensins (HDs) specifically secreted by intestinal Paneth cells. The lectin-like HD5, rather than HD6, bound ACE2 with a high affinity of 39.3 nM and weakened the subsequent recruitment of 2019-nCoV S1. The cloak of HD5 on the ligand-binding domain of ACE2 was confirmed by molecular dynamic simulation. A remarkable dose-dependent preventive effect of HD5 on 2019-nCoV S1 binding to intestinal epithelial cells was further evidenced by in vitro experiments. Our findings unmasked the innate defense function of lectin-like intestinal defensin against 2019-nCoV, which may provide new insights into the prevention and treatment of 2019-nCoV infection.

microbiology↗

bioRxiv2020

Multiple approaches for massively parallel sequencing of HCoV-19 genomes directly from clinical samples

COVID-19 has caused a major epidemic worldwide, however, much is yet to be known about the epidemiology and evolution of the virus. One reason is that the challenges underneath sequencing HCoV-19 directly from clinical samples have not been completely tackled. Here we illustrate the application of amplicon and hybrid capture (capture)-based sequencing, as well as ultra-high-throughput metatranscriptomic (meta) sequencing in retrieving complete genomes, inter-individual and intra-individual variations of HCoV-19 from clinical samples covering a range of sample types and viral load. We also examine and compare the bias, sensitivity, accuracy, and other characteristics of these approaches in a comprehensive manner. This is, to date, the first work systematically implements amplicon and capture approaches in sequencing HCoV-19, as well as the first comparative study across methods. Our work offers practical solutions for genome sequencing and analyses of HCoV-19 and other emerging viruses.

genomics↗

bioRxiv2020

Reactive oxygen species as important regulators of cell division

Currently, the role of reactive oxygen species (ROS) in plant growth is a topic of interest. In this study, we discuss the role of ROS in cell division. We analyzed ROS impact on the stiffness of plant cell walls and whether ROS play an important role in Brassica napus ability to adapt to cold stress. Cultivated sterile seedlings and calli of cold-tolerant cultivar 16NTS309 were subjected to cold stress at 25{degrees}C and 4{degrees}C, respectively. Under normal conditions, O2.- mainly accumulated in the leaf edges, shoot apical meristem, leaf primordia, root tips, lateral root primordia, calli of meristematic nodular tissues, cambia, vascular bundles and root primordia, which are characterized by high division rates. After exposure to cold stress, the malondialdehyde and ROS (O2.-) contents in roots, stems and leaves of cultivar 16NTS309 were significantly higher than under non-cold conditions (P < 0.05). ROS (O2.-) were not only distributed in these zones, but also in other cells, at higher levels than under normal conditions. A strong ROS-based staining appeared in the cell wall. The results support a dual role for apoplastic ROS, in which they have direct effects on the stiffness of the cell wall, because ROS cleave cell-wall, and act as wall loosening agents, thereby either promoting or restricting cellular division. This promotes the appearance of new shoots and a strong root system, allowing plants to adapt to cold stress.

plant biology↗

bioRxiv2020

Tracing the origin of a new organ by inferring the genetic basis of rumen evolution

The rumen is the hallmark organ of ruminants and hosts a diverse ecosystem of microorganisms that facilitates efficient digestion of plant fibers. We used 897 transcriptomes from three Cetartiodactyla lineages: ruminants, camels and cetaceans, as well as data from ruminant comparative genomics and functional assays to explore the genetic basis of rumen origin and evolution. Comparative analyses reveal that the rumen and the first-chamber stomachs of camels and cetaceans shared a common tissue origin from the esophagus. The rumen recruited genes from other tissues/organs and up-regulated many esophagus genes to aquire functional innovations involving epithelium absorption, improvement of the ketone body metabolism and regulation of microbial community. These innovations involve such genetic changes as ruminant-specific conserved elements, newly evolved genes and positively selected genes. Our in vitro experiements validate the functions of one enhancer, one positively selected gene and two newly evolved antibacterial genes. Our study provides novel insights into the origin and evolution of a complex organ.

evolutionary biology↗

bioRxiv2020

Characterizing Sleep-Wake Circadian Rhythm Consolidation in Early Childhood and Its Association with Motor Development Using Actigraphy

BackgroundWearable devices have been widely used in clinical studies to study daily activity patterns, but the analysis remains the major obstacle for researchers. Study ObjectiveThis study proposed a novel method to characterize sleep-activity rhythms using actigraphy and further used it to describe early childhood daily rhythm formation and examine its association with physical development. MethodsWe developed a machine learning-based Penalized Multi-band Learning (PML) algorithm to sequentially infer dominant periodicities based on Fast Fourier Transform (FFT) and further characterize daily rhythms. We implemented and applied the algorithm to Actiwatch data collected from a 262 healthy infant cohort at 6-, 12-, 18-, and 24-month old, with 159, 101, 111, and 141 subjects participating at each time point respectively. Autocorrelation analysis and Fishers test for harmonic analysis with Bonferroni correction were applied to compare with PML. The association between activity rhythm features and early childhood motor development, assessed by Peabody Developmental Motor Scales-Second Edition (PDMS-2), was studied through linear regression. ResultsPML results showed that 1-day periodicity is most dominant at 6 and 12 months, whereas 1-day, 1/3-day, and 1/2-day periodicities are most dominant at 18 and 24 months. These periodicities are all significant in Fishers test, with 1/4-day periodicity also significant at 12 months. Autocorrelation effectively detected 1-day periodicity but not others. At 6 months, PDMS-2 is associated with assessment seasons. At 12 months, PDMS-2 is associated with seasons and FFT signals at 1/3-day periodicity (P<.001) and 1/2-day periodicity (P=.04). In particular, subcategories of stationary, locomotion, and gross motor are associated with FFT signals at 1/3-day periodicity (P<.001). ConclusionsThe proposed PML algorithm can effectively conduct circadian rhythm analysis using time-series wearable device data. Application of the method effectively characterized sleep-wake rhythm development and identified the association between daily rhythm formation and motor development during early childhood.

neuroscience↗