Publications by authors named "Chunyu Wang"

337 Publications

Experimental and Numerical Investigation into the Heat- and Mass-Transfer Processes of -Butane Adsorption on Activated Carbon.

ACS Omega 2021 Jul 25;6(27):17162-17172. Epub 2021 Jun 25.

Department of Environmental Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617, China.

In this work, the adsorption parameters of -butane vapor on an absorbent were tested following the fixed-bed method. According to the corresponding experiments, the maximum adsorption capacity and breakthrough time of activated carbon (AC) are 0.2674 g·g and 924 min, respectively. According to the two-energy-state model formula and the classical adsorption heat formula, the values of theoretical and actual adsorption heat of AC adsorbing -butane are 5.48 and 5.56 kJ·mol, respectively. The model for adsorption of -butane by an AC fixed bed is based on the analytical solutions to the mass, momentum, and energy conservation equations. The model is built using porous media zone in ANSYS Fluent, the implementation of the model into ANSYS Fluent under user-defined functions (UDFs) is also described, the mass source term and energy source term are loaded into Fluent through UDF, and then the mass- and heat-transfer processes of AC in the absorption of -butane are simulated. Furthermore, the predictions by ANSYS Fluent are compared with in situ experimental data, and the deviation rate of breakthrough time and temperature of six monitoring points is less than 5%. The results verify the accuracy and feasibility of computational fluid dynamics (CFD). Therefore, the model can be used to predict the engineering application of the adsorption of organic gases by various porous media.
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http://dx.doi.org/10.1021/acsomega.0c06273DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8280664PMC
July 2021

Dual adversarial convolutional networks with multi-level cues for pancreatic segmentation.

Phys Med Biol 2021 Jul 16. Epub 2021 Jul 16.

College of Electronic Science and Engineering, Jilin University, Changchun, Jilin, CHINA.

Accurate organ segmentation in medical imaging is a relatively challenging subject, especially for pancreas whose morphological characteristics are subtle but variable. In this paper, a novel dual adversarial convolutional network with multi-level cues (DACN-MC) is proposed for segmenting pancreas from computerized tomography (CT). DACN-MC first involves a duplex adversarial network to a conventional model for biomedical image segmentation, which ensures the facticity of the predicted probability volumes and ulteriorly enhances the quality of the obtained maps. Specifically, one of the adversarial networks urges the predicted maps to resemble the ground truths through importing an extra guidance into the original loss functions. The other adversarial network further judges whether the obtained maps are well-segmented and improves the images quality once again. Then, multi-level cues collection module (MCCM) is introduced to gather much useful details for pancreas segmentation. That is, we collect several sets of material formed by features from different layers and pick out a group with optimal performance into the ultimate algorithm. Experimental results show that the dual adversarial convolutional networks together with multi-level cues collection allow our proposed algorithm achieves competitive segmentation performance via several evaluation indexes.
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http://dx.doi.org/10.1088/1361-6560/ac155fDOI Listing
July 2021

Comparison of postprocedural new-onset atrial fibrillation between transcatheter and surgical aortic valve replacement: A systematic review and meta-analysis based on 16 randomized controlled trials.

Medicine (Baltimore) 2021 Jul;100(28):e26613

Medical Department.

Background: Presently, transcatheter aortic valve replacement (TAVR) as an effective and convenient intervention has been adopted extensively for patients with severe aortic disease. However, after surgical aortic valve replacement (SAVR) and TAVR, the incidence of new-onset atrial fibrillation (NOAF) is prevalently found. This meta-analysis was designed to comprehensively compare the incidence of NOAF at different times after TAVR and SAVR for patients with severe aortic disease.

Methods: A systematic search of PubMed, Embase, Cochrane Library, and Web of Science up to October 1, 2020 was conducted for relevant studies that comparing TAVR and SAVR in the treatment of severe aortic disease. The primary outcomes were the incidence of NOAF with early, midterm and long term follow-up. The secondary outcomes included permanent pacemaker (PM) implantation, myocardial infarction (MI), cardiogenic shock, as well as mortality and other complications. Two reviewers assessed trial quality and extracted the data independently. All statistical analyses were performed using the standard statistical procedures provided in Review Manager 5.2.

Results: A total of 16 studies including 13,310 patients were identified. The pooled results indicated that, compared with SAVR, TAVR experienced a significantly lower incidence of 30-day/in-hospital, 1-year, 2-year, and 5-year NOAF, with pooled risk ratios (RRs) of 0.31 (95% confidence interval [CI] 0.23-0.41; 5725 pts), 0.30 (95% CI 0.24-0.39; 6321 pts), 0.48 (95% CI 0.38-0.61; 3441 pts), and 0.45 (95% CI 0.37-0.55; 2268 pts) respectively. In addition, TAVR showed lower incidence of MI (RR 0.62; 95% CI 0.40-0.97) and cardiogenic shock (RR 0.34; 95% CI 0.19-0.59), but higher incidence of permanent PM (RR 3.16; 95% CI 1.61-6.21) and major vascular complications (RR 2.22; 95% CI 1.14-4.32) at 30-day/in-hospital. At 1- and 2-year after procedure, compared with SAVR, TAVR experienced a significantly higher incidence of neurological events, transient ischemic attacks (TIA), permanent PM, and major vascular complications, respectively. At 5-year after procedure, compared with SAVR, TAVR experienced a significantly higher incidence of TIA and re-intervention respectively. There was no difference in 30-day, 1-year, 2-year, and 5-year all-cause or cardiovascular mortality as well as stroke between TAVR and SAVR.

Conclusions: Our analysis showed that TAVR was superior to SAVR in decreasing the both short and long term postprocedural NOAF. TAVR was equal to SAVR in early, midterm and long term mortality. In addition, TAVR showed lower incidence of 30-day/in-hospital MI and cardiogenic shock after procedure. However, pooled results showed that TAVR was inferior to SAVR in reducing permanent pacemaker implantation, neurological events, TIA, major vascular complications, and re-intervention.
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http://dx.doi.org/10.1097/MD.0000000000026613DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8284731PMC
July 2021

Oxidative Stress Signaling in Blast TBI-Induced Tau Phosphorylation.

Antioxidants (Basel) 2021 Jun 15;10(6). Epub 2021 Jun 15.

Department of Pathology, Case Western Reserve University, Cleveland, OH 44106, USA.

Traumatic brain injury caused by blast is associated with long-term neuropathological changes including tau phosphorylation and pathology. In this study, we aimed to determine changes in initial tau phosphorylation after exposure to a single mild blast and the potential contribution of oxidative stress response pathways. C57BL/6 mice were exposed to a single blast overpressure (BOP) generated by a compressed gas-driven shock tube that recapitulates battlefield-relevant open-field BOP, and cortical tissues were harvested at different time points up to 24 h after blast for Western blot analysis. We found that BOP caused elevated tau phosphorylation at Ser202/Thr205 detected by the AT8 antibody at 1 h post-blast followed by tau phosphorylation at additional sites (Ser262 and Ser396/Ser404 detected by PHF1 antibody) and conformational changes detected by Alz50 antibody. BOP also induced acute oxidative damage at 1 h post-blast and gradually declined overtime. Interestingly, Extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) were acutely activated in a similar temporal pattern as the rise and fall in oxidative stress after blast, with p38 showing a similar trend. However, glycogen synthase kinase-3 β (GSK3β) was inhibited at 1 h and remained inhibited for 24 h post blast. These results suggested that mitogen-activated protein kinases (MAPKs but not GSK3β are likely involved in mediating the effects of oxidative stress on the initial increase of tau phosphorylation following a single mild blast.
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http://dx.doi.org/10.3390/antiox10060955DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8232162PMC
June 2021

Effects of Alzheimer's Disease-Related Proteins on the Chirality of Brain Endothelial Cells.

Cell Mol Bioeng 2021 Jun 22;14(3):231-240. Epub 2021 Mar 22.

Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180 USA.

Introduction: Cell chirality is an intrinsic cellular property that determines the directionality of cellular polarization along the left-right axis. We recently show that endothelial cell chirality can influence intercellular junction formation and alter trans-endothelial permeability, depending on the uniformity of the chirality of adjacent cells, which suggests a potential role for cell chirality in neurodegenerative diseases with blood-brain barrier (BBB) dysfunctions, such as Alzheimer's disease (AD). In this study, we determined the effects of AD-related proteins amyloid-β (Aβ), tau, and apolipoprotein E4 (ApoE4) on the chiral bias of the endothelial cell component in BBB.

Methods: We first examined the chiral bias and effects of protein kinase C (PKC)-mediated chiral alterations of human brain microvascular endothelial cells (hBMECs) using the ring micropattern chirality assay. We then investigated the effects of Aβ, tau, and ApoE4 on hBMEC chirality using chirality assay and biased organelle positions.

Results: The hBMECs have a strong clockwise chiral bias, which can be reversed by protein kinase C (PKC) activation. Treatment with tau significantly disrupted the chiral bias of hBMECs with altered cellular polarization. In contrast, neither ApoE4 nor Aβ-42 caused significant changes in cell chirality.

Conclusions: We conclude that tau might cause BBB dysfunction by disrupting cell polarization and chiral morphogenesis, while the effects of ApoE4 and Aβ-42 on BBB integrity might be chirality-independent. The potential involvement of chiral morphogenesis in tau-mediated BBB dysfunction in AD provides a novel perspective in vascular dysfunction in tauopathies such as AD, chronic traumatic encephalopathy, progressive supranuclear palsy, and frontotemporal dementia.

Supplementary Information: The online version contains supplementary material available at 10.1007/s12195-021-00669-w.
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http://dx.doi.org/10.1007/s12195-021-00669-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8175509PMC
June 2021

A new method for detecting intramolecular H-bonds of aromatic amides based on the de-shielding effect of carbonyl groups on β-protons.

Phys Chem Chem Phys 2021 Jun;23(23):13284-13291

State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, China.

Aromatic amide foldamers with highly predictable conformations possess potential for application in the fields of stereoselective recognition, charge transport and catalysis, whose conformations are commonly limited by the intramolecular hydrogen bonding between amide groups and hydrogen-bonding receptors. Herein, on the basis of the de-shielding effect of carbonyl groups on β-protons, we develop a new method for detecting intramolecular hydrogen bonds of aromatic amide compounds. The solvent-related changes in the βH chemical shifts (Δ(δβH)) and NH chemical shifts (Δ(δNH)) of three kinds of amide compounds, which are frequently used as building blocks of aromatic amide foldamers, were recorded in chloroform, nitromethane, acetonitrile and DMSO. The Δ(δβH) method is found to be highly suitable for studying methoxy-benzamides and fluoro-benzamides in chloroform and DMSO. It is worth noting that a reference compound is not required for applying the Δ(δβH) method, which is an advantage over the Δ(δNH) method. In addition, we extend the Δ(δNH) method from methoxy-benzamides to pyridine-carboxamides and fluoro-benzamides in chloroform and DMSO, and propose that nitromethane and acetonitrile will be possible alternatives for the Δ(δNH) method if a test compound is not soluble in chloroform.
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http://dx.doi.org/10.1039/d1cp01089aDOI Listing
June 2021

The Sulfation Code of Tauopathies: Heparan Sulfate Proteoglycans in the Prion Like Spread of Tau Pathology.

Front Mol Biosci 2021 20;8:671458. Epub 2021 May 20.

Department of Biological Sciences, Department of Chemistry and Chemical Biology, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, United States.

Tauopathies are a heterogenous family of progressive neurodegenerative diseases defined by the appearance of proteinaceous lesions within the brain composed of abnormally folded species of Microtubule Associated Protein Tau (tau). Alzheimer's Disease (AD), the most common tauopathy, is the leading cause of cognitive decline among the elderly and is responsible for more than half of all cases of senile dementia worldwide. The characteristic pathology of many tauopathies-AD included-presents as Neurofibrillary Tangles (NFTs), insoluble inclusions found within the neurons of the central nervous system composed primarily of tau protein arranged into Paired Helical Fibrils (PHFs). The spatial extent of this pathology evolves in a remarkably consistent pattern over the course of disease progression. Among the leading hypotheses which seek to explain the stereotypical progression of tauopathies is the , which proposes that the spread of tau pathology is mediated by the transmission of self-propagating tau conformers between cells in a fashion analogous to the mechanism of communicable prion diseases. Protein-glycan interactions between tau and Heparan Sulfate Proteoglycans (HSPGs) have been implicated as a key facilitator in each stage of the prion-like propagation of tau pathology, from the initial secretion of intracellular tau protein into the extracellular matrix, to the uptake of pathogenic tau seeds by cells, and the self-assembly of tau into higher order aggregates. In this review we outline the biochemical basis of the tau-HS interaction and discuss our current understanding of the mechanisms by which these interactions contribute to the propagation of tau pathology in tauopathies, with a particular focus on AD.
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http://dx.doi.org/10.3389/fmolb.2021.671458DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8173255PMC
May 2021

An alternative domain-swapped structure of the Pyrococcus horikoshii PolII mini-intein.

Sci Rep 2021 Jun 3;11(1):11680. Epub 2021 Jun 3.

Department of Chemistry, College of the Holy Cross, 1 College Street, Worcester, MA, USA.

Protein splicing is a post-translational process by which an intein catalyzes its own excision from flanking polypeptides, or exteins, concomitant with extein ligation. Many inteins have nested homing endonuclease domains that facilitate their propagation into intein-less alleles, whereas other inteins lack the homing endonuclease (HEN) and are called mini-inteins. The mini-intein that interrupts the DNA PolII of Pyrococcus horikoshii has a linker region in place of the HEN domain that is shorter than the linker in a closely related intein from Pyrococcus abyssi. The P. horikoshii PolII intein requires a higher temperature for catalytic activity and is more stable to digestion by the thermostable protease thermolysin, suggesting that it is more rigid than the P. abyssi intein. We solved a crystal structure of the intein precursor that revealed a domain-swapped dimer. Inteins found as domain swapped dimers have been shown to promote intein-mediated protein alternative splicing, but the solved P. horikoshii PolII intein structure has an active site unlikely to be catalytically competent.
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http://dx.doi.org/10.1038/s41598-021-91090-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8175363PMC
June 2021

Etomidate attenuates hyperoxia-induced acute lung injury in mice by modulating the Nrf2/HO-1 signaling pathway.

Exp Ther Med 2021 Jul 19;22(1):785. Epub 2021 May 19.

Department of Anesthesiology, Shanxi Provincial People's Hospital, Taiyuan, Shanxi 030012, P.R. China.

The present study aimed to investigate the protective effects of etomidate on hyperoxia-induced acute lung injury in mice, particularly on the nuclear factor-erythroid 2-related factor 2 (Nrf2)/heme oxygenase 1 (HO-1) pathway. Fifty specific pathogen-free mice were randomly divided into the blank control, model, high oxygen exposure + low etomidate dose (0.3 mg·kg), a high oxygen exposure + moderate etomidate dose (3 mg·kg), and a high oxygen exposure + high etomidate dose (10 mg·kg) groups, with ten mice allotted per group. After 72 h, the mice were sacrificed and the lung tissues were harvested, and the wet-to-dry (W/D) ratio of the tissues was calculated. Hematoxylin-eosin staining was performed to observe the pathological changes in the lung tissues, and the lung injury score (LIS) was calculated. The mRNA and protein expression levels of Nrf2 and HO-1 were measured. The malondialdehyde (MDA), myeloperoxidase (MPO), superoxide dismutase (SOD) and catalase (CAT) levels were also measured, and interleukin (IL)-1β, IL-6, tumor necrosis factor alpha (TNF-α) and IL-10 concentrations in the bronchoalveolar lavage fluid were determined. At low and moderate doses, etomidate decreased pathological damage in the lung tissue, decreased the LIS and W/D ratio, upregulated Nrf2 and HO-1 mRNA and protein expression, decreased IL-1β, IL-6, and TNF-α concentrations, increased MPO activity and IL-10 levels, suppressed the production of the oxidation product MDA, and enhanced the activities of the antioxidant enzymes CAT and SOD. Within a certain dose range, etomidate enhanced antioxidant and anti-inflammatory effects in mice, thereby decreasing lung injury induced by the chronic inhalation of oxygen at high concentrations. Furthermore, the underlying mechanism may be associate with the upregulation of the Nrf2/HO-1 signaling pathway.
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http://dx.doi.org/10.3892/etm.2021.10217DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8145798PMC
July 2021

Secondary hemicrania continua-tic syndrome associated with fungal sphenoiditis: A case report.

Clin Case Rep 2021 May 19;9(5):e04297. Epub 2021 May 19.

Department of Neurology The 940th Hospital of Chinese PLA Lanzhou China.

The coexistence of hemicrania-continua and trigeminal neuralgia is called HC-tic syndrome. We describe a case of an elderly man who suffered both types of headache related to fungal sphenoiditis. This is the first case to be reported, to the best of our knowledge.
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http://dx.doi.org/10.1002/ccr3.4297DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8133077PMC
May 2021

Diverged Early From CtpB and CtpC, CtpA Has Evolved to Process D1 Precursor in Oxygenic Photosynthetic Organisms.

Front Plant Sci 2021 30;12:676036. Epub 2021 Apr 30.

Chinese Education Ministry's Key Laboratory of Western Resources and Modern Biotechnology, Northwest University, Xi'an, China.

C-terminal peptidase (Ctp) cleaves the C-terminal extension of the D1 precursor (pD1) to form mature D1. Among the three homologs CtpA, CtpB, and CtpC in photosynthetic organisms only the first is capable of processing pD1 while the roles of CtpB and CtpC remain elusive. Phylogenetic analysis of Ctps from photosynthetic organisms revealed that CtpA has diverged early from CtpB and CtpC during evolution implying distinct roles for the Ctps. Analysis of Arabidopsis Ctp-deficient mutants revealed that pD1 processing was not affected in , , or mutants, demonstrating that AtCtpA, not AtCtpB or AtCtpC, is responsible for cleaving the pD1 C-terminal extension. Ectopic expression of from , , and in rescued the lethal phenotype of the mutant indicating that SeCtpA, CrCtpA, and PpCtpA could process pD1 in Arabidopsis. Enzyme activity assays showed that PpCtpA and CrCtpA could convert pD1 into mature D1 . In contrast, expressing CtpB or CtpC from Arabidopsis, , or in did not rescue its D1 maturation deficiency, and enzyme activity assays also showed that neither CtpB nor CtpC could process pD1 Taken together, we conclude that the function of pD1 processing by CtpA is conserved in photosynthetic organisms. It is possible that among other factors CtpA developed this function to initiate the formation of the oxygenic D1/D2 type PSII complex during evolution whereas CtpB or CtpC have other roles that are still unclear.
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http://dx.doi.org/10.3389/fpls.2021.676036DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8121967PMC
April 2021

Data for the lipase catalyzed synthesis of cyano-containing multi-substituted indoles.

Data Brief 2021 Jun 10;36:107045. Epub 2021 Apr 10.

Key Laboratory of Molecular Enzymology and Engineering of Ministry of Education, School of Life Sciences, Jilin University, Changchun 130023, PR China.

The data presented here are related to the research paper entitled "Efficient Synthesis of Cyano-containing Multi-substituted Indoles Catalyzed by Lipase" [1]. In this data article, the lipase catalyzed synthetic procedures for the preparation of multi-substituted indoles and their derivatives were described. In total, 11 compounds were obtained and the optimum pH, reaction time and substrate ratio were screened through this study.
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http://dx.doi.org/10.1016/j.dib.2021.107045DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8095106PMC
June 2021

Development and evaluation of a novelty single-step cleanup followed by HPLC-QTRAP-MS/MS for rapid analysis of tricaine, tetracaine, and bupivacaine in fish samples.

Biomed Chromatogr 2021 May 14:e5176. Epub 2021 May 14.

Chinese Academy of Fishery Sciences, Beijing, P. R. China.

A novelty single-step cleanup method combined with HPLC coupled with triple quadrupole-linear ion trap MS/MS (HPLC-QTRAP-MS/MS) was developed for the analysis of tricaine, tetracaine, and bupivacaine in fish tissue. The target analytes were extracted using acetonitrile based on the modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) method under ultrasound irradiation. A cheap analytical filtration syringe (CAFS) cleanup column for single-step purification was proposed first; 300 mg of primary/secondary amino was proposed as the optimum purification sorbent; 1 mL of acetonitrile extract was transferred into a CAFS cleanup column and purified for analysis using HPLC-QTRAP-MS/MS. The limits of detection and the limits of quantification were 2.0 and 5.0 μg kg , respectively. The recoveries were in the range of 88.73-108.72%. Inter-day and intra-day relative standard deviations were lower than 15% for all analytes. The developed method has been applied to measure real samples obtained from the local market.
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http://dx.doi.org/10.1002/bmc.5176DOI Listing
May 2021

Semantically Synchronizing Multiple-Camera Systems with Human Pose Estimation.

Sensors (Basel) 2021 Apr 2;21(7). Epub 2021 Apr 2.

School of Instrument Science and Engineering, Southeast University, Nanjing 210096, China.

Multiple-camera systems can expand coverage and mitigate occlusion problems. However, temporal synchronization remains a problem for budget cameras and capture devices. We propose an out-of-the-box framework to temporally synchronize multiple cameras using semantic human pose estimation from the videos. Human pose predictions are obtained with an out-of-the-shelf pose estimator for each camera. Our method firstly calibrates each pair of cameras by minimizing an energy function related to epipolar distances. We also propose a simple yet effective multiple-person association algorithm across cameras and a score-regularized energy function for improved performance. Secondly, we integrate the synchronized camera pairs into a graph and derive the optimal temporal displacement configuration for the multiple-camera system. We evaluate our method on four public benchmark datasets and demonstrate robust sub-frame synchronization accuracy on all of them.
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http://dx.doi.org/10.3390/s21072464DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8038137PMC
April 2021

Bavachin enhances NLRP3 inflammasome activation induced by ATP or nigericin and causes idiosyncratic hepatotoxicity.

Front Med 2021 Apr 28. Epub 2021 Apr 28.

China Military Institute of Chinese Materia, the Fifth Medical Centre, Chinese PLA General Hospital, Beijing, 100039, China.

Psoraleae Fructus (PF) is a well-known traditional herbal medicine in China, and it is widely used for osteoporosis, vitiligo, and other diseases in clinical settings. However, liver injury caused by PF and its preparations has been frequently reported in recent years. Our previous studies have demonstrated that PF could cause idiosyncratic drug-induced liver injury (IDILI), but the mechanism underlying its hepatotoxicity remains unclear. This paper reports that bavachin isolated from PF enhances the specific stimuli-induced activation of the NLRP3 inflammasome and leads to hepatotoxicity. Bavachin boosts the secretion of IL-1β and caspase-1 caused by ATP or nigericin but not those induced by poly(I:C), monosodium urate crystal, or intracellular lipopolysaccharide. Bavachin does not affect AIM2 or NLRC4 inflammasome activation. Mechanistically, bavachin specifically increases the production of nigericin-induced mitochondrial reactive oxygen species among the most important upstream events in the activation of the NLRP3 inflammasome. Bavachin increases the levels of aspartate transaminase and alanine aminotransferase in serum and hepatocyte injury accompanied by the secretion of IL-1β via a mouse model of lipopolysaccharide-mediated susceptibility to IDILI. These results suggest that bavachin specifically enhances the ATP- or nigericin-induced activation of the NLRP3 inflammasome. Bavachin also potentially contributes to PF-induced idiosyncratic hepatotoxicity. Moreover, bavachin and PF should be evaded among patients with diseases linked to the ATP- or nigericin-mediated activation of the NLRP3 inflammasome, which may be a dangerous factor for liver injury.
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http://dx.doi.org/10.1007/s11684-020-0809-2DOI Listing
April 2021

Long Noncoding RNA ZEB1-AS1 Downregulates miR-23a, Promotes Tumor Progression, and Predicts the Survival of Oral Squamous Cell Carcinoma Patients.

Onco Targets Ther 2021 16;14:2699-2710. Epub 2021 Apr 16.

Department of Oral and Maxillofacial Surgery, School of Stomatology, China Medical University, Shengyang, Liaoning, 110002, People's Republic of China.

Background: Long non-coding RNAs (lncRNAs) are implicated in cancer-related biological processes such as cell proliferation, cell cycle progression, cell migration, cell invasion, and chemoresistance. However, the effects of the lncRNA ZEB1-AS1 on oral squamous cell carcinoma (OSCC) have not been adequately demonstrated. The aims of our current study were to explore the roles of lncRNA ZEB1-AS1 in OSCC progression to reveal the potential mechanism.

Methods: Quantitative real-time polymerase chain reaction (qRT-PCR) was used to measure relative ZEB1-AS1 expression levels in OSCC tissues and adjacent non-cancerous tissues. The biological functions of ZEB1-AS1 in OSCC growth and progression were identified by cell proliferation, wound healing, and in vitro transwell assays as well as in vivo xenograft model. The underlying mechanism was detected with a dual-luciferase reporter (DLR) assay.

Results: The up-regulation of ZEB1-AS1 and downregulation of miR-23a-3p (miR-23a) were found in OSCC cancer tissues. A ZEB1-AS1 knockdown remarkably suppressed in vitro cancerous, biological processes of OSCC cell lines such as cell proliferation, invasion, migration, and epithelial-mesenchymal transition (EMT). The tumor growth was also inhibited by silencing ZEB1-AS1 in vivo, and a DLR assay confirmed the association between ZEB1-AS1 and miR-23a.

Conclusion: The newly identified lncRNA ZEB1-AS1 functions as a tumor promoter in OSCC through regulation of miR-23a. Based on these results, ZEB1-AS1 could be a valid molecular target for treating oral cancer.
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http://dx.doi.org/10.2147/OTT.S297209DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8057792PMC
April 2021

Inhibition of Staphylococcus aureus biofilm-forming functional amyloid by molecular tweezers.

Cell Chem Biol 2021 Apr 2. Epub 2021 Apr 2.

Department of Chemistry, Ben Gurion University of the Negev, Beer Sheva 84105, Israel; Ilse Katz Institute for Nanotechnology, Ben Gurion University of the Negev, Beer Sheva 84105, Israel. Electronic address:

Biofilms are rigid and largely impenetrable three-dimensional matrices constituting virulence determinants of various pathogenic bacteria. Here, we demonstrate that molecular tweezers, unique supramolecular artificial receptors, modulate biofilm formation of Staphylococcus aureus. In particular, the tweezers affect the structural and assembly properties of phenol-soluble modulin α1 (PSMα1), a biofilm-scaffolding functional amyloid peptide secreted by S. aureus. The data reveal that CLR01, a diphosphate tweezer, exhibits significant S. aureus biofilm inhibition and disrupts PSMα1 self-assembly and fibrillation, likely through inclusion of lysine side chains of the peptide. In comparison, different peptide binding occurs in the case of CLR05, a tweezer containing methylenecarboxylate units, which exhibits lower affinity for the lysine residues yet disrupts S. aureus biofilm more strongly than CLR01. Our study points to a possible role for molecular tweezers as potent biofilm inhibitors and antibacterial agents, particularly against untreatable biofilm-forming and PSM-producing bacteria, such as methicillin-resistant S. aureus.
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http://dx.doi.org/10.1016/j.chembiol.2021.03.013DOI Listing
April 2021

Risk factors for cognitive impairment in patients with first-time ischemic stroke.

Am J Transl Res 2021 15;13(3):1884-1889. Epub 2021 Mar 15.

Department of The Third Neurology, Cangzhou Central Hospital Cangzhou 061000, Hebei, China.

Objective: To determine the risk factors for cognitive impairment (CI) in patients with first-time ischemic stroke.

Methods: The clinical data of 180 patients with ischemic stroke who were admitted to our hospital from January 2018 to December 2019 was retrospectively analyzed. Patients with MMSE score ≤24 were included into the CI group and the rest of the patients were placed into the normal group. Multivariate logistic regression was applied to describe risk factors for CI in patients with first-time ischemic stroke.

Results: Among the patients with first-time ischemic stroke, 96 cases (53%) developed CI, 84 cases (47%) were normal. In different subtypes of TOAST classifications, patients with large-artery atherosclerosis had the highest CI incidence (66.96%). For different infarction sites, the highest CI incidence occurred in the frontal lobe (82.35%), and the lowest was from cerebellar infarction (37.50%). The difference of CI incidences in the frontal lobe, parietal lobe, temporal lobe and occipital lobe was significant between the two groups (P<0.05). Logistic regression analysis indicated that independent risk factors for CI in patients with first ischemic stroke include age ≥60 years old, diabetes history, CRP >6.53 mg/L, Hcy >13.84 μmol/L, NIHSS score >4.37, VD <45.16 nmol/L, and the difference was statistically significant (<0.05).

Conclusion: The study showed a high CI incidence in patients with preexisting ischemic stroke. Age ≥60 years old, history of diabetes mellitus, CRP >6.53 mg/L, Hcy >13.84 μmol/L, NIHSS score >4.37 score, VD <45.16 nmol/L are independent risk factors for CI in patients with first-time ischemic stroke.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8014415PMC
March 2021

Changes in Degree Centrality of Network Nodes in Different Frequency Bands in Parkinson's Disease With Depression and Without Depression.

Front Neurosci 2021 22;15:638554. Epub 2021 Mar 22.

Department of Radiology, The Second Xiangya Hospital, Central South University, Changsha, China.

Background: Depression induces an early onset of Parkinson's disease (PD), aggravates dyskinesia and cognitive impairment, and accelerates disease progression. However, it is very difficult to identify and diagnose PD with depression (PDD) in the early clinical stage. Few studies have suggested that the changes in neural networks are associated with PDD, while degree centrality (DC) has been documented to be effective in detecting brain network changes.

Objectives: The objectives of this study are to explore DC changes between patients with PDD and without depression (PDND) and to find the key brain hubs involved with depression in PD patients.

Methods: One hundred and four PD patients and 54 healthy controls (HCs) underwent brain resting-state functional magnetic resonance imaging. The Data Processing and Analysis of Brain Imaging and Resting-State Functional Magnetic Resonance Data Analysis Toolkit were used for processing and statistical analysis. The DC value of each frequency band was calculated. One-way analysis of variance and a two-sample -test for comparison were used to compare the differences of the DC values in different frequency bands among PDD, PDND, and healthy control group. Gaussian random field was used for multiple comparison correction. Pearson correlation analysis was performed between each individual's DC map and clinical indicators.

Results: The DC value of different brain regions changed in PDD and PDND in different frequency bands. The prefrontal lobe, limbic system, and basal ganglia were the main brain regions involved. PDD patients showed a wider range and more abnormal brain areas in the slow-4 frequency band (0.027-0.073 Hz) compared to the HCs. PDD showed a decreased DC value in the medial frontal gyrus, bilateral cuneus gyrus, right lingual gyrus, bilateral supplementary motor area (SMA), bilateral superior frontal gyrus, and left paracentral lobule, but an increased DC value in the bilateral brainstem, midbrain, bilateral parahippocampal gyrus, cerebellum, left superior temporal gyrus, bilateral insula, left fusiform gyrus, and left caudate nucleus in the traditional frequency band (0.01-0.08 Hz) compared to PDND patients. PDND patients displayed more abnormal functions in the basal ganglia in the slow-4 frequency band.

Conclusion: The DC changes in PDD and PDND are frequency dependent and frequency specific. The medial frontal gyrus, SMA, and limbic system may be the key hubs for depression in PD.
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http://dx.doi.org/10.3389/fnins.2021.638554DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8019799PMC
March 2021

Critical downstream analysis steps for single-cell RNA sequencing data.

Brief Bioinform 2021 Apr 5. Epub 2021 Apr 5.

Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China.

Single-cell RNA sequencing (scRNA-seq) has enabled us to study biological questions at the single-cell level. Currently, many analysis tools are available to better utilize these relatively noisy data. In this review, we summarize the most widely used methods for critical downstream analysis steps (i.e. clustering, trajectory inference, cell-type annotation and integrating datasets). The advantages and limitations are comprehensively discussed, and we provide suggestions for choosing proper methods in different situations. We hope this paper will be useful for scRNA-seq data analysts and bioinformatics tool developers.
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http://dx.doi.org/10.1093/bib/bbab105DOI Listing
April 2021

Facile Approach to Fabricate a High-Performance Superhydrophobic Mesh.

ACS Appl Mater Interfaces 2021 Apr 25;13(13):15720-15726. Epub 2021 Mar 25.

Institute of Polymer Science and Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China.

When superhydrophobic meshes are used for oil/water separation, high flux and high intrusion pressure are usually compromised. Herein, a high-performance superhydrophobic stainless steel mesh membrane with a hairy-like poly(divinylbenzene) (PDVB) coating is fabricated by precipitated cationic polymerization. The synthesis is facile, which is completed in one step at ambient temperature within a short time, i.e., less than 90 s. The unique hair-like microstructure of PDVB is responsible for the superhydrophobic performance with less blockage for the pores. A higher flux for oil is achieved while keeping a high intrusion pressure. Especially, the ellipsoidal pore texture with two sharp tips can give additional high intrusion pressure. In the case of 2800 mesh, the superhydrophobic mesh displays an unprecedentedly high value of up to 22 kPa while maintaining a high flux of 2.0 × 10 L·m·h. The high intrusion pressure enables further increment of flux to 4.2 × 10 L·m·h under a reduced pressure at a higher loading. The current high-performance superhydrophobic mesh realizes higher efficiency in separating oil/water mixtures, which is promising for practical applications, for example, in industrial extraction.
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http://dx.doi.org/10.1021/acsami.1c03475DOI Listing
April 2021

Unexpected Oligomerization of Small α-Dicarbonyls for Secondary Organic Aerosol and Brown Carbon Formation.

Environ Sci Technol 2021 04 15;55(8):4430-4439. Epub 2021 Mar 15.

Department of Atmospheric Sciences, Texas A&M University, College Station, Texas 77843, United States.

Large amounts of small α-dicarbonyls (glyoxal and methylglyoxal) are produced in the atmosphere from photochemical oxidation of biogenic isoprene and anthropogenic aromatics, but the fundamental mechanisms leading to secondary organic aerosol (SOA) and brown carbon (BrC) formation remain elusive. Methylglyoxal is commonly believed to be less reactive than glyoxal because of unreactive methyl substitution, and available laboratory measurements showed negligible aerosol growth from methylglyoxal. Herein, we present experimental results to demonstrate striking oligomerization of small α-dicarbonyls leading to SOA and BrC formation on sub-micrometer aerosols. Significantly more efficient growth and browning of aerosols occur upon exposure to methylglyoxal than glyoxal under atmospherically relevant concentrations and in the absence/presence of gas-phase ammonia and formaldehyde, and nonvolatile oligomers and light-absorbing nitrogen-heterocycles are identified as the dominant particle-phase products. The distinct aerosol growth and light absorption are attributed to carbenium ion-mediated nucleophilic addition, interfacial electric field-induced attraction, and synergetic oligomerization involving organic/inorganic species, leading to surface- or volume-limited reactions that are dependent on the reactivity and gaseous concentrations. Our findings resolve an outstanding discrepancy concerning the multiphase chemistry of small α-dicarbonyls and unravel a new avenue for SOA and BrC formation from atmospherically abundant, ubiquitous carbonyls and ammonia/ammonium sulfate.
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http://dx.doi.org/10.1021/acs.est.0c08066DOI Listing
April 2021

Genomic Analyses for Predictors of Response to Chemoradiation in Stage III Non-Small Cell Lung Cancer.

Adv Radiat Oncol 2021 Jan-Feb;6(1):100615. Epub 2020 Nov 14.

Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York City, New York.

Background: Radiation with platinum-based chemotherapy is the standard of care for unresectable stage III non-small cell lung cancer (NSCLC). Despite aggressive treatment, progression-free survival and overall survival remain poor. It is unclear whether any tumor genetic mutations are associated with response to chemoradiation therapy.

Methods: We retrospectively reviewed clinical outcomes of patients with stage III NSCLC treated with definitive radiation who had undergone tumor molecular profiling through a next-generation DNA sequencing platform. Cox proportional hazards model was used to investigate associations between clinical outcomes and genetic mutations detected by next-generation sequencing.

Results: 110 patients were identified with stage III NSCLC and underwent definitive radiation between 2013 and 2017 and tumor molecular profiling. Concurrent or sequential chemotherapy was given in 104 patients (95%). Unbiased genomic analyses revealed a significant association between mutations and decreased local-regional tumor control and overall survival (hazard ratios [HR] 12.5 and 13.7, = .003 and = .003, respectively). Analyses restricted to loss-of-function mutations identified and deleterious mutations as negative prognostic factors for overall survival (HR 13.4 and 7.0, < .001 and < .001, respectively). Deleterious mutations in a panel of 38 DNA damage response and repair pathway genes were associated with improved local-regional control (HR 0.32, = .049).

Conclusions: This study coupled multiplexed targeted sequencing with clinical outcome and identified mutations in and as negative predictors of local-regional control and survival, and deleterious mutations in damage response and repair pathway genes were associated with improved local-regional disease control after chemoradiation therapy. These findings will require validation in a larger cohort of patients with prospectively collected and detailed clinical information.
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http://dx.doi.org/10.1016/j.adro.2020.10.027DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7897765PMC
November 2020

The function of BAP18 on modulation of androgen receptor action in luteinized granulosa cells from normal weight women with and without PCOS.

Mol Cell Endocrinol 2021 05 1;527:111228. Epub 2021 Mar 1.

Center of Reproductive Medicine, Shengjing Hospital of China Medical University, Shenyang City, Liaoning Province, 110004, China. Electronic address:

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders in reproductive-age women. In this study, BPTF associated protein of 18 kDa (BAP18) is decreased in luteinized granulosa cells (GCs) from PCOS women. BAP18 depletion significantly decreases CYP19A1 expression levels, leading to an abrogation in transfer capacity of androgen to estrogen in GCs. Also, BAP18 knockdown delays cell cycle G1 to S phase transition and induces cell apoptosis to decrease GCs proliferation. We also provide evidence showing BAP18 interacts with androgen receptor (AR) and enhances AR-mediated transactivation in GCs. Results indicate that AR or BAP18 recruits to androgen response elements (AREs) of CYP19A1 and FSHR, which are putative AR-induced genes in GCs. BAP18 interacts with Sp1 transcription factor and co-recruits to the promoter region of AR gene, resulting in AR transactivation in GCs. Taken together, these data provide new insights on the pathophysiology of PCOS.
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http://dx.doi.org/10.1016/j.mce.2021.111228DOI Listing
May 2021

Removal of Matrix Interferences by Nano-MgO and Co-Adsorbents for Accurate Multi-Pesticide Residue Analysis in the Chinese Medicinal Herb, .

J Anal Methods Chem 2021 4;2021:6626257. Epub 2021 Feb 4.

State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Institute of Quality and Standard of Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China.

A simple, accurate, and high-throughput analytical method was developed to detect 123 pesticide residues in Chinese medicinal herb (PRA) by introducing nano-MgO as a highly efficient purification material based on quick, easy, cheap, effective, rugged, and safe (QuEChERS) design concept. Various PRA samples were extracted using 8 mL 0.5% acetic acid-acetonitrile solution and purified by a dispersive solid-phase extraction method with 30 mg nano-MgO, 40 mg primary secondary amine (PSA), and 40 mg octadecylsilane (C18) as the cleanup adsorbents, followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). 70.7% of pesticides showed a weak matrix effect after the purification process, indicating that this method can give the precise quantitative analysis of trace pesticides residue. The method was systematically validated under optimal conditions in five different kinds of PRA samples; good linearity was observed in the concentration range of 0.5-250 g/L or 1-250 g/L. Pesticide recovery in each sample spiked at concentrations of 20, 50, and 200 g/kg ranged from 98.0% to 111% and the mean relative standard deviation ranged from 2.72% to 5.70%. Furthermore, the method comparison with the traditional QuEChERS method suggested the feasibility, advantages, and potential application prospect of the present method for the multi-pesticide residue analysis in various PRA samples.
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http://dx.doi.org/10.1155/2021/6626257DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7880715PMC
February 2021

pH-dependent and dynamic interactions of cystatin C with heparan sulfate.

Commun Biol 2021 02 12;4(1):198. Epub 2021 Feb 12.

Department of Oral Biology, The University at Buffalo, Buffalo, NY, USA.

Cystatin C (Cst-3) is a potent inhibitor of cysteine proteases with diverse biological functions. As a secreted protein, the potential interaction between Cst-3 and extracellular matrix components has not been well studied. Here we investigated the interaction between Cst-3 and heparan sulfate (HS), a major component of extracellular matrix. We discovered that Cst-3 is a HS-binding protein only at acidic pH. By NMR and site-directed mutagenesis, we identified two HS binding regions in Cst-3: the highly dynamic N-terminal segment and a flexible region located between residue 70-94. The composition of the HS-binding site by two highly dynamic halves is unique in known HS-binding proteins. We further discovered that HS-binding severely impairs the inhibitory activity of Cst-3 towards papain, suggesting the interaction could actively regulate Cst-3 activity. Using murine bone tissues, we showed that Cst-3 interacts with bone matrix HS at low pH, again highlighting the physiological relevance of our discovery.
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http://dx.doi.org/10.1038/s42003-021-01737-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7881039PMC
February 2021

EGCG binds intrinsically disordered N-terminal domain of p53 and disrupts p53-MDM2 interaction.

Nat Commun 2021 02 12;12(1):986. Epub 2021 Feb 12.

Center for Biotechnology and Interdisciplinary Studies, Department of Chemistry and Chemical Biology, Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, NY, USA.

Epigallocatechin gallate (EGCG) from green tea can induce apoptosis in cancerous cells, but the underlying molecular mechanisms remain poorly understood. Using SPR and NMR, here we report a direct, μM interaction between EGCG and the tumor suppressor p53 (K = 1.6 ± 1.4 μM), with the disordered N-terminal domain (NTD) identified as the major binding site (K = 4 ± 2 μM). Large scale atomistic simulations (>100 μs), SAXS and AUC demonstrate that EGCG-NTD interaction is dynamic and EGCG causes the emergence of a subpopulation of compact bound conformations. The EGCG-p53 interaction disrupts p53 interaction with its regulatory E3 ligase MDM2 and inhibits ubiquitination of p53 by MDM2 in an in vitro ubiquitination assay, likely stabilizing p53 for anti-tumor activity. Our work provides insights into the mechanisms for EGCG's anticancer activity and identifies p53 NTD as a target for cancer drug discovery through dynamic interactions with small molecules.
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http://dx.doi.org/10.1038/s41467-021-21258-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7881117PMC
February 2021

Early changes of NLRP3 inflammasome activation after hypoxic-ischemic brain injury in neonatal rats.

Int J Clin Exp Pathol 2021 1;14(2):209-220. Epub 2021 Feb 1.

Children's Neurorehabilitation Laboratory, Shenyang Children's Hospital Shenyang, China.

The pathogenesis of neonatal hypoxic-ischemic (HI) brain injury may involve activation of the NOD-like receptor family pyrin domain-containing-3 (NLRP3) inflammasome and its downstream effectors, caspase-1 and interleukin (IL)-1β. The start time of therapy is associated with adverse neurodevelopmental outcome following HI injury. We performed this study investigating early dynamic changes in NLRP3, caspase-1, and IL-1β expression during the first 24 h following HI brain injury in an animal model, in order to optimize selection of treatment time after injury. Rats were randomized to an HI group (n=40) and sham group (n=40). Rats in the HI group were subjected to right common carotid artery ligation and then exposed to hypoxia (8% O) for 2 h, and divided into 5 subgroups with 8 cases in each group at 5 postoperative time points (0, 4, 8, 12, 24 h). Brain injury during the first 24 h after surgery/hypoxia was evaluated by cranial ultrasonography. RT-PCR, western blot, and immunohistochemistry were applied to determine protein and mRNA expressions. In the HI group, ultrasonography revealed accelerated right vertebrobasilar artery flow at 4 h, enhanced brain parenchyma echogenicity at 24 h, and blood stealing from the vertebrobasilar artery at 24 h. In the HI group, immunohistochemistry demonstrated elevated expressions of NLRP3 and IL-1β at 4, 8, 12, and 24 h and enhanced expression of caspase-1 at 8 and 12 h (all < 0.01). Western blot and RT-PCR revealed that, compared with the sham group, the HI group exhibited elevated expression of NLRP3 at 4, 8, and 24 h, caspase-1 at 12 h, and IL-1β at 8 h (all < 0.05). In summary, the present results suggested that activation of NLRP3/caspase-1/IL-1β signaling occurs within 4 h of HI brain injury in the neonatal rat.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7868790PMC
February 2021

Neighborhood Geometric Structure-Preserving Variational Autoencoder for Smooth and Bounded Data Sources.

IEEE Trans Neural Netw Learn Syst 2021 Feb 8;PP. Epub 2021 Feb 8.

Many data sources, such as human poses, lie on low-dimensional manifolds that are smooth and bounded. Learning low-dimensional representations for such data is an important problem. One typical solution is to utilize encoder-decoder networks. However, due to the lack of effective regularization in latent space, the learned representations usually do not preserve the essential data relations. For example, adjacent video frames in a sequence may be encoded into very different zones across the latent space with holes in between. This is problematic for many tasks such as denoising because slightly perturbed data have the risk of being encoded into very different latent variables, leaving output unpredictable. To resolve this problem, we first propose a neighborhood geometric structure-preserving variational autoencoder (SP-VAE), which not only maximizes the evidence lower bound but also encourages latent variables to preserve their structures as in ambient space. Then, we learn a set of small surfaces to approximately bound the learned manifold to deal with holes in latent space. We extensively validate the properties of our approach by reconstruction, denoising, and random image generation experiments on a number of data sources, including synthetic Swiss roll, human pose sequences, and facial expression images. The experimental results show that our approach learns more smooth manifolds than the baselines. We also apply our approach to the tasks of human pose refinement and facial expression image interpolation where it gets better results than the baselines.
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http://dx.doi.org/10.1109/TNNLS.2021.3053591DOI Listing
February 2021