Publications by authors named "Xiao Xu"

1,265 Publications

  • Page 1 of 1

Competing Nodal d-Wave Superconductivity and Antiferromagnetism.

Phys Rev Lett 2021 May;126(21):217002

Department of Physics, University of California at San Diego, La Jolla, California 92093, USA.

Competing unconventional superconductivity and antiferromagnetism widely exist in several strongly correlated quantum materials whose direct simulation generally suffers from fermion sign problem. Here, we report unbiased quantum Monte Carlo (QMC) simulations on a sign-problem-free repulsive toy model with same on site symmetries as the standard Hubbard model on a 2D square lattice. Using QMC simulations, supplemented with mean-field and continuum field-theory arguments, we find that it hosts three distinct phases: a nodal d-wave phase, an antiferromagnet, and an intervening phase which hosts coexisting antiferromagnetism and nodeless d-wave superconductivity. The transition from the coexisting phase to the antiferromagnet is described by the 2+1-D XY universality class, while the one from the coexisting phase to the nodal d-wave phase is described by the Heisenberg-Gross-Neveu theory. The topology of our phase diagram resembles that of layered organic materials which host pressure tuned Mott transition from antiferromagnet to unconventional superconductor at half-filling.
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http://dx.doi.org/10.1103/PhysRevLett.126.217002DOI Listing
May 2021

Chromosome 10 abnormality predicts prognosis of neuroblastoma patients with bone marrow metastasis.

Ital J Pediatr 2021 Jun 9;47(1):134. Epub 2021 Jun 9.

Medical Oncology Department, Pediatric Oncology Center, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing Key Laboratory of Pediatric Hematology Oncology, Key Laboratory of Major Diseases in Children, Ministry of Education, Beijing, 100045, China.

Background: Neuroblastoma (NB) is the most common extracranial solid tumor in children. It is known for high heterogeneity and concealed onset. In recent years, the mechanism of its occurrence and development has been gradually revealed. The purpose of this study is to summarize the clinical characteristics of children with NB and abnormal chromosome 10, and to investigate the relationship between the number and structure of chromosome 10 abnormalities and NB prognosis.

Methods: Chromosome G-banding was used at the time of diagnosis to evaluate the genetics of chromosomes in patients with NB and track their clinical characteristics and prognosis. All participants were diagnosed with NB in the Medical Oncology Department of the Beijing Children's Hospital from May 2015 to December 2018 and were followed up with for at least 1 year.

Results: Of all 150 patients with bone marrow metastases, 42 were clearly diagnosed with chromosomal abnormalities. Thirteen patients showed abnormalities in chromosome 10, and chromosome 10 was the most commonly missing chromosome. These 13 patients had higher LDH and lower OS and EFS than children with chromosomal abnormalities who did not have an abnormality in chromosome 10. Eight patients had both MYCN amplification and 1p36 deletion. Two patients had optic nerve damage and no vision, and one patient had left supraorbital metastases 5 months after treatment.

Conclusions: The results indicated that chromosome 10 might be a new prognostic marker for NB. MYCN amplification and 1p36 deletion may be related to chromosome 10 abnormalities in NB. Additionally, NB patients with abnormal chromosome 10 were prone to orbital metastases.
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http://dx.doi.org/10.1186/s13052-021-01085-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8190999PMC
June 2021

MicroRNA miR-92a-3p regulates breast cancer cell proliferation and metastasis via regulating B-cell translocation gene 2 (BTG2).

Bioengineered 2021 Dec;12(1):2033-2044

Department of Gynecology, Affiliated Hospital of Jining Medical University. Jining, Shandong, China.

MicroRNAs (miRNAs) dysregulation contributes to tumorigenesis, and it is reported that abnormal miR-92a-3p expression participates in multiple cancers' occurrence and progression. This study focuses on miR-92a-3p's functions and regulatory mechanism in breast cancer (BC). The current study proved miR-92a-3p expression was enhanced in BC tissues and cells, and its high expression was related to increased TNM stage and larger tumor size of BC patients. Functionally, transfection of miR-92a-3p mimics facilitated BC cell proliferation and metastasis, yet transfection of miR-92a-3p inhibitors functioned oppositely. In addition, BTG2 was verified as a direct miR-92a-3p target in BC cells. This research indicated that miR-92a-3p facilitates BC cell proliferation and metastasis through repressing BTG2 expression.
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http://dx.doi.org/10.1080/21655979.2021.1924543DOI Listing
December 2021

Fibrinogen-mimicking, multiarm nanovesicles for human thrombus-specific delivery of tissue plasminogen activator and targeted thrombolytic therapy.

Sci Adv 2021 Jun 2;7(23). Epub 2021 Jun 2.

Department of Chemical Engineering, Imperial College London, South Kensington Campus, London, UK.

Clinical use of tissue plasminogen activator (tPA) in thrombolytic therapy is limited by its short circulation time and hemorrhagic side effects. Inspired by fibrinogen binding to activated platelets, we report a fibrinogen-mimicking, multiarm nanovesicle for thrombus-specific tPA delivery and targeted thrombolysis. This biomimetic system is based on the lipid nanovesicle coated with polyethylene glycol (PEG) terminally conjugated with a cyclic RGD (cRGD) peptide. Our experiments with human blood demonstrated its highly selective binding to activated platelets and efficient tPA release at a thrombus site under both static and physiological flow conditions. Its clot dissolution time in a microfluidic system was comparable to that of free tPA. Furthermore, we report a purpose-built computational model capable of simulating targeted thrombolysis of the tPA-loaded nanovesicle and with a potential in predicting the dynamics of thrombolysis in physiologically realistic scenarios. This combined experimental and computational work presents a promising platform for development of thrombolytic nanomedicines.
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http://dx.doi.org/10.1126/sciadv.abf9033DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8172176PMC
June 2021

Association of hemodynamic factors and progressive aortic dilatation following type A aortic dissection surgical repair.

Sci Rep 2021 Jun 1;11(1):11521. Epub 2021 Jun 1.

Department of Chemical Engineering, Imperial College London, London, SW7 2AZ, UK.

Type A aortic dissection (TAAD) involves the ascending aorta or the arch. Acute TAAD usually requires urgent replacement of the ascending aorta. However, a subset of these patients develops aortic rupture due to further dilatation of the residual dissected aorta. There is currently no reliable means to predict the risk of dilatation following TAAD repair. In this study, we performed a comprehensive morphological and hemodynamic analysis for patients with and without progressive aortic dilatation following surgical replacement of the ascending aorta. Patient-specific models of repaired TAAD were reconstructed from post-surgery computed tomography images for detailed computational fluid dynamic analysis. Geometric and hemodynamic parameters were evaluated and compared between patients with stable aortic diameters (N = 9) and those with aortic dilatation (N = 8). Our results showed that the number of re-entry tears and true/false lumen pressure difference were significantly different between the two groups. Patients with progressive aortic dilatation had higher luminal pressure difference (6.7 [4.6, 10.9] vs. 0.9 [0.5, 2.3] mmHg; P = 0.001) and fewer re-entry tears (1.5 [1, 2.8] vs. 5 [3.3, 7.5]; P = 0.02) compared to patients with stable aortic diameters, suggesting that these factors may serve as potential predictors of aneurysmal dilatation following surgical repair of TAAD.
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http://dx.doi.org/10.1038/s41598-021-91079-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8169847PMC
June 2021

pH and Reduction Dual-Responsive Bi-Drugs Conjugated Dextran Assemblies for Combination Chemotherapy and In Vitro Evaluation.

Polymers (Basel) 2021 May 8;13(9). Epub 2021 May 8.

Shandong Provincial Key Laboratory of Molecular Engineering, School of Chemistry and Chemical Engineering, Qilu University of Technology (Shandong Academy of Science), Jinan 250353, China.

Polymeric prodrugs, synthesized by conjugating chemotherapeutic agents to functional polymers, have been extensively investigated and employed for safer and more efficacious cancer therapy. By rational design, a pH and reduction dual-sensitive dextran-di-drugs conjugate (oDex-g-Pt+DOX) was synthesized by the covalent conjugation of Pt (IV) prodrug and doxorubicin (DOX) to an oxidized dextran (oDex). Pt (IV) prodrug and DOX were linked by the versatile efficient esterification reactions and Schiff base reaction, respectively. oDex-g-Pt+DOX could self-assemble into nanoparticles with an average diameter at around 180 nm. The acidic and reductive (GSH) environment induced degradation and drug release behavior of the resulting nanoparticles (oDex-g-Pt+DOX NPs) were systematically investigated by optical experiment, DLS analysis, TEM measurement, and in vitro drugs release experiment. Effective cellular uptake of the oDex-g-Pt+DOX NPs was identified by the human cervical carcinoma HeLa cells via confocal laser scanning microscopy. Furthermore, oDex-g-Pt+DOX NPs displayed a comparable antiproliferative activity than the simple combination of free cisplatin and DOX (Cis+DOX) as the extension of time. More importantly, oDex-g-Pt+DOX NPs exhibited remarkable reversal ability of tumor resistance compared to the cisplatin in cisplatin-resistant lung carcinoma A549 cells. Take advantage of the acidic and reductive microenvironment of tumors, this smart polymer-dual-drugs conjugate could serve as a promising and effective nanomedicine for combination chemotherapy.
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http://dx.doi.org/10.3390/polym13091515DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8125917PMC
May 2021

Correlations for Concentration Polarization and Pressure Drop in Spacer-Filled RO Membrane Modules Based on CFD Simulations.

Membranes (Basel) 2021 May 1;11(5). Epub 2021 May 1.

Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK.

Empirical correlations for mass transfer coefficient and friction factor are often used in process models for reverse osmosis (RO) membrane systems. These usually involve four dimensionless groups, namely Reynolds number (Re), Sherwood number (Sh), friction factor (), and Schmidt number (Sc), with the associated coefficients and exponents being obtained by fitting to experimental data. However, the range of geometric and operating conditions covered by the experiments is often limited. In this study, new dimensionless correlations for concentration polarization (CP) modulus and friction factor are presented, which are obtained by dimensional analysis and using simulation data from computational fluid dynamics (CFD). Two-dimensional CFD simulations are performed on three configurations of spacer-filled channels with 76 combinations of operating and geometric conditions for each configuration, covering a broad range of conditions encountered in RO membrane systems. Results obtained with the new correlations are compared with those from existing correlations in the literature. There is good consistency in the predicted CP with mean discrepancies less than 6%, but larger discrepancies for pressure gradient are found among the various friction factor correlations. Furthermore, the new correlations are implemented in a process model with six spiral wound modules in series and the predicted recovery, pressure drop, and specific energy consumption are compared with a reference case obtained by ROSA (Reverse Osmosis System Analysis, The Dow Chemical Company). Differences in predicted recovery and pressure drop are up to 5% and 83%, respectively, highlighting the need for careful selection of correlations when using predictive models in process design. Compared to existing mass transfer correlations, a distinct advantage of our correlations for CP modulus is that they can be directly used to estimate the impact of permeate flux on CP at a membrane surface without having to resort to the film theory.
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http://dx.doi.org/10.3390/membranes11050338DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8147287PMC
May 2021

Drug Resistance to HIV-1 Integrase Inhibitors among Treatment-naive Patients in Jiangsu, China.

Biomed Environ Sci 2021 May;34(5):400-403

Department of Epidemiology and Health Statistics, Key Laboratory of Environmental Medicine Engineering of Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, Jiangsu, China.

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http://dx.doi.org/10.3967/bes2021.053DOI Listing
May 2021

Wavelength-Selective Activation of Photocaged DNAzymes for Metal Ion Sensing in Live Cells.

ACS Omega 2021 May 12;6(20):13153-13160. Epub 2021 May 12.

Department of Chemistry, Beijing Key Laboratory for Microanalytical Methods and Instrumentation, Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, China.

RNA-cleaving DNAzymes are widely applied as sensors for detecting metal ions in environmental samples owing to their high sensitivity and selectivity, but their use for sensing biological metal ions in live cells is challenging because constitutive sensors fail to report the spatiotemporal heterogeneity of biological processes. Photocaged DNAzymes can be activated by light for sensing purposes that need spatial and temporal resolution. Studying complex biological processes requires logic photocontrol, but unfortunately all the literature-reported photocaged DNAzymes working in live cells cannot be selectively controlled by light irradiation at different wavelengths. In this work, we developed photocaged DNAzymes responsive to UV and visible light using a general synthetic method based on phosphorothioate chemistry. Taking the Zn-dependent DNAzyme sensor as a model, we achieved wavelength-selective activation of photocaged DNAzymes in live human cells by UV and visible light, laying the groundwork for the logic activation of DNAzyme-based sensors in biological systems.
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http://dx.doi.org/10.1021/acsomega.1c00976DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8158819PMC
May 2021

Nanoparticle Delivery of CRISPR/Cas9 for Genome Editing.

Front Genet 2021 12;12:673286. Epub 2021 May 12.

Department of Child and Adolescent Psychiatry, Shenzhen Kangning Hospital, Shenzhen Mental Health Center, Shenzhen Key Laboratory for Psychological Healthcare & Shenzhen Institute of Mental Health, Shenzhen, China.

The emerging clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated system (Cas) gene-editing system represents a promising tool for genome manipulation. However, its low intracellular delivery efficiency severely compromises its use and potency for clinical applications. Nanocarriers, such as liposomes, polymers, and inorganic nanoparticles, have shown great potential for gene delivery. The remarkable development of nanoparticles as non-viral carriers for the delivery of the CRISPR/Cas9 system has shown great promise for therapeutic applications. In this review, we briefly summarize the delivery components of the CRISPR/Cas9 system and report on the progress of nano-system development for CRISPR/Cas9 delivery. We also compare the advantages of various nano-delivery systems and their applications to deliver CRISPR/Cas9 for disease treatment. Nano-delivery systems can be modified to fulfill the tasks of targeting cells or tissues. We primarily emphasize the novel exosome-based CRISPR/Cas9 delivery system. Overall, we review the challenges, development trends, and application prospects of nanoparticle-based technology for CRISPR/Cas9 delivery.
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http://dx.doi.org/10.3389/fgene.2021.673286DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8149999PMC
May 2021

Structure, Biological Activities and Metabolism of Flavonoid Glucuronides.

Mini Rev Med Chem 2021 May 21. Epub 2021 May 21.

Key Laboratory of Hui Ethnic Medicine Modernization, Ministry of Education, Ningxia 750004, China.

Background: Flavonoid glucuronides are a kind of natural products which present a flavone linked directly with one or several glucuronides through O-glycoside bond. They had become of interest in natural product research in the past decades for their antioxidant, anti-inflammatory, and anti-bacteria activities. In particular, the compound breviscapine has a notable effect on cardio-cerebrovascular diseases. Several other compounds even have antitumor activity.

Methods: Through searching the database and reading a large number of documents, we summarized the related findings of flavonoid glucuronides.

Results: We summarized 211 naturally occurring flavonoid glucuronides in 119 references with their chemical structures, biological activities, and metabolism. A total of 220 references from 1953 to 2020 were cited in this paper according to literature databases such as CNKI, Weipu, Wanfang data, Elsevier, Springer, Wiley, NCBI, PubMed, EmBase, etc..

Conclusion: Flavonoid glucuronides are a class of compounds with various chemical structures and a diverse range of biological activities. And they are thought to be potential candidates for drug discovery, but the specific study on their mechanisms is still limited until now. We hope this article can provide references for natural product researchers and draw more attention to flavonoid glucuronides' biological activities and mechanisms.
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http://dx.doi.org/10.2174/1389557521666210521221352DOI Listing
May 2021

Electronic Modulation of Non-van der Waals 2D Electrocatalysts for Efficient Energy Conversion.

Adv Mater 2021 May 25:e2008422. Epub 2021 May 25.

School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, 637459, Singapore.

The exploration of efficient electrocatalysts for energy conversion is important for green energy development. Owing to their high surface areas and unusual electronic structure, 2D electrocatalysts have attracted increasing interest. Among them, non-van der Waals (non-vdW) 2D materials with numerous chemical bonds in all three dimensions and novel chemical and electronic properties beyond those of vdW 2D materials have been studied increasingly over the past decades. Herein, the progress of non-vdW 2D electrocatalysts is critically reviewed, with a special emphasis on electronic structure modulation. Strategies for heteroatom doping, vacancy engineering, pore creation, alloying, and heterostructure engineering are analyzed for tuning electronic structures and achieving intrinsically enhanced electrocatalytic performances. Lastly, a roadmap for the future development of non-vdW 2D electrocatalysts is provided from material, mechanism, and performance viewpoints.
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http://dx.doi.org/10.1002/adma.202008422DOI Listing
May 2021

Kramers nodal line metals.

Nat Commun 2021 May 24;12(1):3064. Epub 2021 May 24.

Department of Physics, Hong Kong University of Science and Technology, Hong Kong, China.

Recently, it was pointed out that all chiral crystals with spin-orbit coupling (SOC) can be Kramers Weyl semimetals (KWSs) which possess Weyl points pinned at time-reversal invariant momenta. In this work, we show that all achiral non-centrosymmetric materials with SOC can be a new class of topological materials, which we term Kramers nodal line metals (KNLMs). In KNLMs, there are doubly degenerate lines, which we call Kramers nodal lines (KNLs), connecting time-reversal invariant momenta. The KNLs create two types of Fermi surfaces, namely, the spindle torus type and the octdong type. Interestingly, all the electrons on octdong Fermi surfaces are described by two-dimensional massless Dirac Hamiltonians. These materials support quantized optical conductance in thin films. We further show that KNLMs can be regarded as parent states of KWSs. Therefore, we conclude that all non-centrosymmetric metals with SOC are topological, as they can be either KWSs or KNLMs.
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http://dx.doi.org/10.1038/s41467-021-22903-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8144424PMC
May 2021

Differential impact of non-pharmaceutical public health interventions on COVID-19 epidemics in the United States.

BMC Public Health 2021 05 21;21(1):965. Epub 2021 May 21.

Center for Global Health and Infectious Diseases, School of Medicine, Tsinghua University, Beijing, China.

Background: The widespread pandemic of novel coronavirus disease 2019 (COVID-19) poses an unprecedented global health crisis. In the United States (US), different state governments have adopted various combinations of non-pharmaceutical public health interventions (NPIs), such as non-essential business closures and gathering bans, to mitigate the epidemic from February to April, 2020. Quantitative assessment on the effectiveness of NPIs is greatly needed to assist in guiding individualized decision making for adjustment of interventions in the US and around the world. However, the impacts of these approaches remain uncertain.

Methods: Based on the reported cases, the effective reproduction number (R) of COVID-19 epidemic for 50 states in the US was estimated. Measurements on the effectiveness of nine different NPIs were conducted by assessing risk ratios (RRs) between R and NPIs through a generalized linear model (GLM).

Results: Different NPIs were found to have led to different levels of reduction in R. Stay-at-home contributed approximately 51% (95% CI 46-57%), wearing (face) masks 29% (15-42%), gathering ban (more than 10 people) 19% (14-24%), non-essential business closure 16% (10-21%), declaration of emergency 13% (8-17%), interstate travel restriction 11% (5-16%), school closure 10% (7-14%), initial business closure 10% (6-14%), and gathering ban (more than 50 people) 7% (2-11%).

Conclusions: This retrospective assessment of NPIs on R has shown that NPIs played critical roles on epidemic control in the US in the past several months. The quantitative results could guide individualized decision making for future adjustment of NPIs in the US and other countries for COVID-19 and other similar infectious diseases.
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http://dx.doi.org/10.1186/s12889-021-10950-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8139542PMC
May 2021

Comparison of high-throughput single-cell RNA sequencing data processing pipelines.

Brief Bioinform 2021 May;22(3)

Digital Fujian Institute of Healthcare and Biomedical Big Data, School of Informatic, Xiamen University.

With the development of single-cell RNA sequencing (scRNA-seq) technology, it has become possible to perform large-scale transcript profiling for tens of thousands of cells in a single experiment. Many analysis pipelines have been developed for data generated from different high-throughput scRNA-seq platforms, bringing a new challenge to users to choose a proper workflow that is efficient, robust and reliable for a specific sequencing platform. Moreover, as the amount of public scRNA-seq data has increased rapidly, integrated analysis of scRNA-seq data from different sources has become increasingly popular. However, it remains unclear whether such integrated analysis would be biassed if the data were processed by different upstream pipelines. In this study, we encapsulated seven existing high-throughput scRNA-seq data processing pipelines with Nextflow, a general integrative workflow management framework, and evaluated their performance in terms of running time, computational resource consumption and data analysis consistency using eight public datasets generated from five different high-throughput scRNA-seq platforms. Our work provides a useful guideline for the selection of scRNA-seq data processing pipelines based on their performance on different real datasets. In addition, these guidelines can serve as a performance evaluation framework for future developments in high-throughput scRNA-seq data processing.
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http://dx.doi.org/10.1093/bib/bbaa116DOI Listing
May 2021

Attractin Gene Deficiency in Rats Leads to Impairments in Both Activity and Spatial Learning and Memory.

Neuroscience 2021 Jul 14;466:101-108. Epub 2021 May 14.

School of Medicine, Jiangsu University, Zhenjiang 212013, Jiangsu Province, PR China. Electronic address:

Attractin (ATRN), an autosomal recessive gene that is widely distributed in the brain, is involved in the execution of a variety of brain functions and associated with certain neuropsychiatric disorders. Here, we introduce a novel rat strain harboring a mutation in ATRN that was generated by knocking in ATRN-G505C via the CRISPR/Cas9 system. We assessed the behavioral performance of these mutant ATRN knock-in rats. The G505C mutation was introduced into exon 9, and a synthetic primer was inserted into introns 8-9 for genotyping. The 505th amino acid, a Gly (G) residue, was mutated to a Cys (C) residue, i.e., GGC was mutated to TGC. Behavioral experiments showed that homozygous ATRN rats spent significantly more time searching for the escape platform in the acquisition trial and significantly less time in the target area in the probe trial in the Morris water maze (MWM) test and traveled a significantly shorter distance in the open field test (OFT) than wild-type rats. In addition, Western blot analysis and immunohistochemistry showed that rats with the mutant ATRN gene exhibited significantly reduced expression of brain-derived neurotrophic factor (BDNF). In summary, our results indicate that mutations in the ATRN gene directly lead to learning and memory impairments and slight motor deficits. These findings provide new clues for the mechanism by which mutant ATRN induces neurodegenerative changes.
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http://dx.doi.org/10.1016/j.neuroscience.2021.05.006DOI Listing
July 2021

Intelligent phototriggered nanoparticles induce a domino effect for multimodal tumor therapy.

Theranostics 2021 19;11(13):6477-6490. Epub 2021 Apr 19.

State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Bioactive Natural Product Research, School of Traditional Chinese Pharmacy, China Pharmaceutical University, 24 Tong Jia Xiang, Nanjing 210009, PR China.

: Integration of several monotherapies into a single nanosystem can produce remarkable synergistic antitumor effects compared with separate delivery of combination therapies. We developed near-infrared (NIR) light-triggered nanoparticles that induce a domino effect for multimodal tumor therapy. : The designed intelligent phototriggered nanoparticles (IPNs) were composed of a copper sulfide-loaded upconversion nanoparticle core, a thermosensitive and photosensitive enaminitrile molecule (EM) organogel shell loaded with anticancer drugs, and a cancer cell membrane coating. Irradiation with an NIR laser activated a domino effect beginning with photothermal generation by copper sulfide for photothermal therapy that also resulted in phase transformation of the EM gel to release the anticancer drug. Meanwhile, the NIR light energy was converted to ultraviolet light by the upconversion core to excite the EM, which generated reactive oxygen species for photodynamic therapy. : IPNs achieved excellent antitumor effects and with little systemic toxicity, indicating that IPNs could serve as a safe and high-performance instrument for synergetic antitumor therapy. : This intelligent drug delivery system induced a chain reaction generating multiple antitumor therapies after a single stimulus.
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http://dx.doi.org/10.7150/thno.55708DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8120229PMC
April 2021

Ubiquitin-specific peptidase 22 in cancer.

Cancer Lett 2021 Aug 11;514:30-37. Epub 2021 May 11.

Department of Hepatobiliary and Pancreatic Surgery, The Center for Integrated Oncology and Precision Medicine, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, China. Electronic address:

Recently, many studies have shown that deubiquitination modification of proteins is of great significance in major physiological processes such as cell proliferation, apoptosis, and differentiation. The ubiquitin-specific peptidase (USP) family is one of the most numerous and structurally diverse of the deubiquitinates known to date. USP22, an important member of the USP family, has been found to be closely associated with tumor cell cycle regulation, stemness maintenance, invasion and metastasis, chemoresistance, and immune regulation. We focus on recent advances regarding USP22's function in cancer and discuss the prospect of USP22 in this review.
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http://dx.doi.org/10.1016/j.canlet.2021.05.004DOI Listing
August 2021

A KLF4/PiHL/EZH2/HMGA2 regulatory axis and its function in promoting oxaliplatin-resistance of colorectal cancer.

Cell Death Dis 2021 May 13;12(5):485. Epub 2021 May 13.

Department of Laboratory Medicine, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, 200040, China.

Long noncoding RNAs (lncRNAs) have emerged as a new class of regulatory molecules implicated in therapeutic resistance, yet the mechanisms underlying lncRNA-mediated oxaliplatin resistance in colorectal cancer (CRC) are poorly understood. In this study, lncRNA P53 inHibiting LncRNA (PiHL) was shown to be highly induced in oxaliplatin-resistant CRC cells and tumor tissues. In vitro and in vivo models clarified PiHL's role in conferring resistance to oxaliplatin-induced apoptosis. PiHL antagonized chemosensitivity through binding with EZH2, repressing location of EZH2 to HMGA2 promoter, and downregulating methylation of histone H3 lysine 27 (H3K27me3) level in HMGA2 promoter, thus activating HMGA2 expression. Furthermore, HMGA2 upregulation induced by PiHL promotes PI3K/Akt phosphorylation, which resulted in increased oxaliplatin resistance. We also found that transcription factor KLF4 was downregulated in oxaliplatin-resistant cells, and KLF4 negatively regulated PiHL expression by binding to PiHL promoter. In vivo models further demonstrated that treatment of oxaliplatin-resistant CRC with locked nucleic acids targeting PiHL restored oxaliplatin response. Collectively, this study established lncRNA PiHL as a chemoresistance promoter in CRC, and targeting PiHL/EZH2/HMGA2/PI3K/Akt signaling axis represents a novel choice in the investigation of drug resistance.
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http://dx.doi.org/10.1038/s41419-021-03753-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8119946PMC
May 2021

Localization of Immersed Sources by Modified Convolutional Neural Network: Application to a Deep-Sea Experiment.

Sensors (Basel) 2021 Apr 29;21(9). Epub 2021 Apr 29.

Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190, China.

A modified convolutional neural network (CNN) is proposed to enhance the reliability of source ranging based on acoustic field data received by a vertical array. Compared to the traditional method, the output layer is modified by outputting Gauss regression sequences, expressed using a Gaussian probability distribution form centered on the actual distance. The processed results of deep-sea experimental data confirmed that the ranging performance of the CNN with a Gauss regression output was better than that using single regression and classification outputs. The mean relative error between the predicted distance and the actual value was ~2.77%, and the positioning accuracy with 10% and 5% error was 99.56% and 90.14%, respectively.
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http://dx.doi.org/10.3390/s21093109DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8124261PMC
April 2021

Sirolimus-based immunosuppression improves the prognosis of liver Transplantation Recipients with low TSC1/2 expression in hepatocellular carcinoma beyond the Milan Criteria.

Eur J Surg Oncol 2021 Apr 19. Epub 2021 Apr 19.

Department of Hepatobiliary and Pancreatic Surgery, The Center for Integrated Oncology and Precision Medicine, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, China; Zhejiang University Cancer Center, Hangzhou, 310058, China; NHC Key Laboratory of Combined Multi-organ Transplantation, Hangzhou, 310003, China; Institute of Organ Transplantation, Zhejiang University, Hangzhou, 310003, China. Electronic address:

Background: The use of the immunosuppressive agent sirolimus (SRL) following liver transplantation (LT) in patients with hepatocellular carcinoma (HCC) is controversial. Sirolimus is a typical mammalian target of rapamycin (mTOR) inhibitor, and tuberous sclerosis 1-tuberous sclerosis 2 complex (TSC1/TSC2) is an important negative effector in the mTOR pathway. In this study, we investigated the effect of SRL-based immunosuppression on the prognosis of LT recipients with HCC beyond the Milan criteria based on TSC1/2 expression and explored the effect of TSC1 on HCC in vitro and in vivo.

Methods: We retrospectively analyzed 120 HCC patients who underwent LT in our hospital between January 1, 2015 and December 30, 2018. All patients had HCC beyond the Milan criteria and were divided into the SRL group (n = 50) and non-SRL group (n = 70). TSC1/2 expression levels in paraffin-embedded tissues were determined by immunohistochemistry (IHC) and then analyzed as subgroups. Overall survival (OS) and disease-free survival (DFS) were analyzed using the Kaplan-Meier method. TSC1 expression was silenced in Huh-7 and Bel-7402 cell lines for further cell function experiments.

Results: 88.3% of patients were HBV LT recipients. The SRL group exhibited better DFS and OS compared to the non-SRL group (P = 0.02, P = 0.003). Subgroup (TSC1-based or TSC2-based) analyses revealed that patients with low TSC1 or TSC2 expression benefited from sirolimus (DFS: P = 0.046, OS: P = 0.006 for TSC1; DFS: P = 0.05, OS: P = 0.003 for TSC2) compared with patients with high expression. TSC1 knockdown in Huh-7 and Bel-7402 HCC cell lines activated the mTORC1 pathway and enhanced cell proliferation, migration and sensitivity to SRL in vitro and in vivo.

Conclusion: TSC1/2 expression could be used to predict the prognosis of patients with HCC beyond the Milan criteria who underwent SRL-based immunosuppression following LT. TSC1 knockdown promoted HCC malignancy and enhanced sensitivity to SRL.
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http://dx.doi.org/10.1016/j.ejso.2021.04.001DOI Listing
April 2021

Overexpression of retinoid X receptor beta provides protection against oxidized low-density lipoprotein-induced inflammation via regulating PGC1α-dependent mitochondrial homeostasis in endothelial cells.

Biochem Pharmacol 2021 Jun 17;188:114559. Epub 2021 Apr 17.

Department of Pharmacology, Nantong University Pharmacy College, Nantong 226001, China. Electronic address:

Retinoid X receptor beta (RXRβ) has been poorly studied in atherosclerosis. The aim of the present study is to explore the function of RXRβ in oxidized low density lipoprotein (ox-LDL)-induced inflammation in endothelial cells and the underlying mechanism. The protein expression of RXRβ in the aorta of atherosclerotic mice was detected. A lentivirus vector for RXRβ overexpression and RNA interference for RXRβ downregulation were constructed and transfected into human aortic endothelial cells (HAECs). The results showed that RXRβ protein expression was downregulated in aorta of high fat diet (HFD)-fed LDLr mice and ox-LDL-treated HAECs. The ox-LDL-induced production of pro-inflammatory cytokines and activations of TLR9/NF-κB and NLRP3/caspase-1 inflammasome pathway were significantly decreased by RXRβ overexpression but increased by RXRβ knockdown in HAECs. The ox‑LDL‑induced mitochondrial damage indicated as the increased generation of mitochondrial ROS, decreased mitochondrial membrane potential and increased mitochondrial DNA release was abolished by RXRβ overexpression but aggravated by RXRβ knockdown. Treatment with mito-TEMPO significantly reduced the increased production of pro-inflammatory cytokines and activations of TLR9/NF-κB and NLRP3/caspase-1 inflammasome induced by RXRβ knockdown in ox-LDL treated HAECs. Moreover, peroxisome proliferator-activated receptor-γ coactivator1α (PGC1α) protein expression was reduced in HFD-fed LDLr mice. RXRβ could interact with PGC1α in HAECs. Ox-LDL-induced reduction of PGC1α was significantly inhibited by RXRβ overexpression and aggravated by RXRβ downregulation. Our further study showed that transfection of PGC1α siRNA abrogated the alleviative effects of RXRβ overexpression on mitochondrial damage and inflammation in ox-LDL treated cells. The present study indicates that RXRβ exerted protective effects against the ox-LDL-induced inflammation may through regulating PGC1α-dependent mitochondrial homeostasis.
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http://dx.doi.org/10.1016/j.bcp.2021.114559DOI Listing
June 2021

Application of phototherapeutic-based nanoparticles in colorectal cancer.

Int J Biol Sci 2021 2;17(5):1361-1381. Epub 2021 Apr 2.

School of Basic Medical Sciences, Henan University, Kaifeng 475004, China.

Colorectal cancer (CRC) is the third most commonly diagnosed malignancy and the second leading cause of cancer death, which accounts for approximately 10% of all new cancer cases worldwide. Surgery is the main method for treatment of early-stage CRC. However, it is not effective for most metastatic tumors, and new treatment and diagnosis strategies need to be developed. Photosensitizers (PSs) play an important role in the treatment of CRC. Phototherapy also has a broad prospect in the treatment of CRC because of its low invasiveness and low toxicity. However, most PSs are associated with limitations including poor solubility, poor selectivity and high toxicity. The application of nanomaterials in PSs has added many advantages, including increased solubility, bioavailability, targeting, stability and low toxicity. In this review, based on phototherapy, we discuss the characteristics and development progress of PSs, the targeting of PSs at organ, cell and molecular levels, and the current methods of optimizing PSs, especially the application of nanoparticles as carriers in CRC. We introduce the photosensitizer (PS) targeting process in photodynamic therapy (PDT), the damage mechanism of PDT, and the application of classic PS in CRC. The action process and damage mechanism of photothermal therapy (PTT) and the types of ablation agents. In addition, we present the imaging examination and the application of PDT / PTT in tumor, including (fluorescence imaging, photoacoustic imaging, nuclear magnetic resonance imaging, nuclear imaging) to provide the basis for the early diagnosis of CRC. Notably, single phototherapy has several limitations , especially for deep tumors. Here, we discuss the advantages of the combination therapy of PDT and PTT compared with the single therapy. At the same time, this review summarizes the clinical application of PS in CRC. Although a variety of nanomaterials are in the research and development stage, few of them are actually on the market, they will show great advantages in the treatment of CRC in the near future.
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http://dx.doi.org/10.7150/ijbs.58773DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8040477PMC
April 2021

Facilitating target search in polymer networks: Effects of target size and mixed one-dimensional and three-dimensional diffusion.

Phys Rev E 2021 Mar;103(3-1):032502

Research Group for Simulations of Energy Materials, Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, D-14109 Berlin, Germany.

We theoretically investigate the problem of diffusive target search and mean first passage times (MFPTs) of a tracer in a three-dimensional (3D) polymer network with a particular focus on the effects of combined one-dimensional (1D) diffusion along the polymer chains and 3D diffusion within the network. For this, we employ computer simulations as well as limiting theories of a single diffusive tracer searching for a spherical target fixed at a cross-link of a homogeneous 3D cubic lattice network. The free parameters are the target size, the ratio of the 1D and 3D friction constants, and the transition probabilities between bound and unbound states. For a very strongly bound tracer on the chains, the expected predominant set of 1D lattice diffusion (LD) is found. The MFPT in the LD process significantly depends on the target size, yielding two distinct scaling behaviors for target sizes smaller and larger than the network mesh size, respectively. In the limit of a pointlike target, the LD search becomes a random walk process on the lattice, which recovers the analytical solution for the MFPT previously reported by S. Condamin, O. Bénichou, and M. Moreau [Phys. Rev. Lett. 95, 260601 (2005)PRLTAO0031-900710.1103/PhysRevLett.95.260601]. For the very weakly bound tracer, the expected 3D free diffusion (FD) dominates, extrapolating to the well-known Smoluchowski limit. A critical target size is found above which the MFPT in the FD process is faster than in the LD process. For intermediate binding, i.e., a combination of LD and FD processes, the target search time can be minimized for an optimal range of target sizes and partitions between FD and LD, for which the MFPTs are substantially faster when compared to the limiting FD or LD processes. Our study may provide a theoretical basis to better understand and predict search and reaction processes in complex structured materials, thereby contributing to practical applications such as designing nanoreactors where catalytic targets are immobilized in polymer networks.
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http://dx.doi.org/10.1103/PhysRevE.103.032502DOI Listing
March 2021

Enhanced tumour penetration and prolonged circulation in blood of polyzwitterion-drug conjugates with cell-membrane affinity.

Nat Biomed Eng 2021 Apr 15. Epub 2021 Apr 15.

Zhejiang Key Laboratory of Smart BioMaterials and Center for Bionanoengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, China.

Effective anticancer nanomedicines need to exhibit prolonged circulation in blood, to extravasate and accumulate in tumours, and to be taken up by tumour cells. These contrasting criteria for persistent circulation and cell-membrane affinity have often led to complex nanoparticle designs with hampered clinical translatability. Here, we show that conjugates of small-molecule anticancer drugs with the polyzwitterion poly(2-(N-oxide-N,N-diethylamino)ethyl methacrylate) have long blood-circulation half-lives and bind reversibly to cell membranes, owing to the negligible interaction of the polyzwitterion with proteins and its weak interaction with phospholipids. Adsorption of the polyzwitterion-drug conjugates to tumour endothelial cells and then to cancer cells favoured their transcytosis-mediated extravasation into tumour interstitium and infiltration into tumours, and led to the eradication of large tumours and patient-derived tumour xenografts in mice. The simplicity and potency of the polyzwitterion-drug conjugates should facilitate the design of translational anticancer nanomedicines.
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http://dx.doi.org/10.1038/s41551-021-00701-4DOI Listing
April 2021

Radiofrequency ablation stereotactic body radiotherapy for stage IA non-small cell lung cancer in nonsurgical patients.

J Cancer 2021 19;12(10):3057-3066. Epub 2021 Mar 19.

Department of Respiratory Medicine, Shanghai 10th People's Hospital, Tongji University School of Medicine, Shanghai 200072, China.

Approximately 20% resectable non-small cell lung cancer (NSCLC) patients are treated non-surgically due to various reasons. The aim of the present study was to compare the effectiveness of radiofrequency ablation (RFA) and stereotactic body radiotherapy (SBRT) in patients with stage IA NSCLC who were ineligible for surgery using the surveillance, epidemiology and end-results (SEER) Database. Using the SEER registry, we identified a total of 6,195 IA NSCLC patients who received SBRT or RFA between 2004 and 2015 because of ineligibility for surgical resection due to various reasons. Complete clinical information was available in all these patients. Overall survival (OS) and cancer-specific survival (CSS) were compared between RFA and SBRT groups by using propensity score matching (PSM), inverse probability of treatment weight (IPTW), and overlap weighting analysis. Additionally, an exploratory analysis was conducted to determine the effectiveness of RFA treatment based on the subsets of clinically relevant patients. Of the 6,195 nonsurgical IA NSCLC patients, 191 patients (3.1%) received RFA and the other 6,004 patients (96.9%) received SBRT. The one-, three- and five-year OS in the unmatched RFA and SBRT groups were 83.3%, 48.5%and 29.1% 83.8%, 48.3% and 27.4%, respectively, there was similar results in the PSM, IPTW, overlap weighing analysis. Nonsurgical IA NSCLC patients receiving RFA seemed to have better five-year survival than those receiving SBRT, though the difference was not statistically significant (OS, HR; 0.986; 95% CI, 0.827-1.175, =0.8738; CSS, HR; 0.965; 95% CI, 0.765-1.219, =0.7663). We found that the odds of receiving RFA decreased with larger tumor size (>2, <3 cm, OR; 0.303; 95% CI, 0.191-0.479; >3 cm, OR; 0.153; 95% CI, 0.093-0.251) compared with tumor size <1 cm. In subgroup analysis, patients receiving RFA seemed to have better OS than those receiving SBRT, though the difference was not statistically significant. This specific trend was even more obvious in patients with tumors <1cm in diameter (=0.1577). In comparison with SBRT, RFA did not seem to adversely affect CSS and OS of IA NSCLC patients who were not suitable for surgical treatment. In addition, RFA seemed to offer better survival to IA NSCLC patients, especially those with tumors <1 cm.
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http://dx.doi.org/10.7150/jca.51413DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8040894PMC
March 2021

Nomogram prediction of vulnerable periodontal condition before orthodontic treatment in the anterior teeth of Chinese patients with skeletal Class III malocclusion.

Acta Odontol Scand 2021 Apr 10:1-9. Epub 2021 Apr 10.

Department of Periodontology, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing Key Laboratory of Digital Stomatology, Beijing, P. R. China.

Objective: To establish and verify models predictive of thin periodontal phenotype and alveolar fenestration/dehiscence in the anterior teeth of patients with skeletal Class III malocclusion.

Material And Methods: Retrospective data of 669 anterior teeth (305 in maxillae and 364 in mandibles) from 80 patients with skeletal Class III malocclusion before augmented corticotomy were collected. Distribution of thin periodontal phenotype and alveolar fenestration and dehiscence were evaluated and their associations with potential influencing factors were explored using univariate and multivariate analyses. The predictive models were visualized as nomograms, the accuracy of which was tested by receiver operating curve analyses.

Results: Thin phenotype was associated with Mazza bleeding index, sex, tooth type, probing depth and width of keratinized gingiva (WKG). Labial dehiscence was associated with age, jaw, labial bone thickness, mandibular plane angle, sagittal root position (SRP), sex, tooth type, and WKG. Labial fenestration was associated with sex, tooth type, SRP, and periodontal phenotype. The areas under the curves of nomogram prediction models for periodontal phenotype, alveolar dehiscence, and alveolar fenestration were 0.84, 0.81, and 0.73, respectively.

Conclusions: Female sex, lateral incisor, and limited WKG may be risk factors for thin periodontal phenotype. Age, canine, male sex, mandible, thin labial bone thickness, and root positioned against the labial plate may be risk factors for labial dehiscence; and female sex, thick phenotype, root positioned against the labial plate, lateral incisor, and canine may be risk factors for labial fenestration. The predictive performance of the models was acceptable.
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http://dx.doi.org/10.1080/00016357.2021.1908595DOI Listing
April 2021

Characterization and functional analysis of two acetylcholinesterase genes in Bradysia odoriphaga Yang et Zhang (Diptera: Sciaridae).

Pestic Biochem Physiol 2021 May 25;174:104807. Epub 2021 Feb 25.

Department of Entomology, China Agricultural University, Beijing 100193, China. Electronic address:

Two acetylcholinesterase genes (Boace1 and Boace2) were cloned from Bradysia odoriphaga, a devastating soil pest that mainly damages Chinese chives. The Boace1 encodes BoAChE1 protein consisting of 696 amino acid residues, while Boace2 encodes BoAChE2 containing 638 amino acids. Phylogenetic analysis showed that Boace1 and Boace2 are appeared to be distinct clusters. The gene expression patterns at different development stages and various body parts tissues were examined, and their biological functions were characterized by RNA interference and analog docking prediction. The results showed that both Boace genes were expressed in all developmental stages and examined tissues. The transcript level of Boace2 was significantly higher than Boace1 in all tested samples, and Boace1 was found most abundant in the head while Boace2 was highly expressed in the fat body of B. odoriphaga. The silencing of Boace1 and Boace2 significantly decreased the AChE activity of 36.6% and 14.8% separately, and increased the susceptibility of B. odoriphaga to phoxim, with 60.8% and 44.7% mortality. Besides, overexpression and gene duplication of Boace1 were found in two field resistant populations, and two major mutations, A319S and G400V, were detected in Boace1. Moreover, the docking results revealed that BoAChE1 had a higher affinity towards organophosphorus than BoAChE2. It is concluded that Boace2 is the most abundant ace type in B. odoriphaga, while both Boace play vital roles. Boace1 might play a major neurological function and more likely be the prime target for insecticides, while Boace2 might play some important unidentified roles.
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http://dx.doi.org/10.1016/j.pestbp.2021.104807DOI Listing
May 2021

Comprehensive transcriptional analysis reveals salt stress-regulated key pathways, hub genes and time-specific responsive gene categories in common bermudagrass (Cynodon dactylon (L.) Pers.) roots.

BMC Plant Biol 2021 Apr 10;21(1):175. Epub 2021 Apr 10.

Coastal Salinity Tolerant Grass Engineering and Technology Research Center, Ludong University, Yantai, Shandong, People's Republic of China.

Background: Despite its good salt-tolerance level, key genes and pathways involved with temporal salt response of common bermudagrass (Cynodon dactylon (L.) Pers.) have not been explored. Therefore, in this study, to understand the underlying regulatory mechanism following the different period of salt exposure, a comprehensive transcriptome analysis of the bermudagrass roots was conducted.

Results: The transcripts regulated after 1 h, 6 h, or 24 h of hydroponic exposure to 200 mM NaCl in the roots of bermudagrass were investigated. Dataset series analysis revealed 16 distinct temporal salt-responsive expression profiles. Enrichment analysis identified potentially important salt responsive genes belonging to specific categories, such as hormonal metabolism, secondary metabolism, misc., cell wall, transcription factors and genes encoded a series of transporters. Weighted gene co-expression network analysis (WGCNA) revealed that lavenderblush2 and brown4 modules were significantly positively correlated with the proline content and peroxidase activity and hub genes within these two modules were further determined. Besides, after 1 h of salt treatment, genes belonging to categories such as signalling receptor kinase, transcription factors, tetrapyrrole synthesis and lipid metabolism were immediately and exclusively up-enriched compared to the subsequent time points, which indicated fast-acting and immediate physiological responses. Genes involved in secondary metabolite biosynthesis such as simple phenols, glucosinolates, isoflavones and tocopherol biosynthesis were exclusively up-regulated after 24 h of salt treatment, suggesting a slightly slower reaction of metabolic adjustment.

Conclusion: Here, we revealed salt-responsive genes belonging to categories that were commonly or differentially expressed in short-term salt stress, suggesting possible adaptive salt response mechanisms in roots. Also, the distinctive salt-response pathways and potential salt-tolerant hub genes investigated can provide useful future references to explore the molecular mechanisms of bermudagrass.
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http://dx.doi.org/10.1186/s12870-021-02939-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8035780PMC
April 2021

Analysis of Turbulence Effects in a Patient-Specific Aorta with Aortic Valve Stenosis.

Cardiovasc Eng Technol 2021 Apr 7. Epub 2021 Apr 7.

Department of Chemical Engineering, Imperial College London, South Kensington Campus, London, SW7 2AZ, UK.

Blood flow in the aorta is often assumed laminar, however aortic valve pathologies may induce transition to turbulence and our understanding of turbulence effects is incomplete. The aim of the study was to provide a detailed analysis of turbulence effects in aortic valve stenosis (AVS).

Methods: Large-eddy simulation (LES) of flow through a patient-specific aorta with AVS was conducted. Magnetic resonance imaging (MRI) was performed and used for geometric reconstruction and patient-specific boundary conditions. Computed velocity field was compared with 4D flow MRI to check qualitative and quantitative consistency. The effect of turbulence was evaluated in terms of fluctuating kinetic energy, turbulence-related wall shear stress (WSS) and energy loss.

Results: Our analysis suggested that turbulence was induced by a combination of a high velocity jet impinging on the arterial wall and a dilated ascending aorta which provided sufficient space for turbulence to develop. Turbulent WSS contributed to 40% of the total WSS in the ascending aorta and 38% in the entire aorta. Viscous and turbulent irreversible energy losses accounted for 3.9 and 2.7% of the total stroke work, respectively.

Conclusions: This study demonstrates the importance of turbulence in assessing aortic haemodynamics in a patient with AVS. Neglecting the turbulent contribution to WSS could potentially result in a significant underestimation of the total WSS. Further work is warranted to extend the analysis to more AVS cases and patients with other aortic valve diseases.
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http://dx.doi.org/10.1007/s13239-021-00536-9DOI Listing
April 2021