Publications by authors named "Yao Zhao"

428 Publications

Fluorescence live cell imaging revealed wogonin targets mitochondria.

Talanta 2021 Aug 23;230:122328. Epub 2021 Mar 23.

Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, People's Republic of China; University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China; Basic Medical College, Shandong University of Traditional Chinese Medicine, Jinan, 250355, PR China; National Centre for Mass Spectrometry in Beijing, China. Electronic address:

Scutellaria baicalensis is one of the widely used Chinese traditional medicines, and wogonin is one of major active components in it. However, the mechanism of action of wogonin has largely remained unclear. In this work, we designed a fluorescent probe, namely ATTO565-WGN, by conjugating wogonin with the fluorophore ATTO565 based on Mannich reaction via a flexible chain linker. In vitro assays verified that the ATTO565-WGN conjugate has a similar anti-proliferative activity to wogonin against human A549 and HeLa cancer cell lines. Combining co-localization and competition studies, confocal fluorescence imaging clearly demonstrated that the fluorescent wogonin probe predominantly located in mitochondrial area of living cells, indicating that wogonin acts at mitochondrion to exert its pharmacological functions. Significantly, the conjugated ATTO565 fluorophore conferred the wogonin probe STED (Stimulated Emission Depletion) feature, enabling STED fluorescence living cell imaging with a 55 nm of ultrahigh spatial resolution. This will greatly beneficial for the in situ investigation of interactions between wogonin and biological targets at the finely organized and dynamic mitochondria of living cells. Moreover, this work also provides novel insights into rational design of mitochondrion targeting fluorescence probes for ultrahigh resolution living cell imaging.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.talanta.2021.122328DOI Listing
August 2021

The effects of Methanococcus maripaludis on the corrosion behavior of EH40 steel in seawater.

Bioelectrochemistry 2021 Apr 21;140:107824. Epub 2021 Apr 21.

Navy Submarine Academy, No. 1 Jinshui Road, Qingdao 266191, China.

The corrosion behavior of EH40 steel in seawater enriched with Methanococcus maripaludis was investigated through electrochemical methods and surface analysis techniques. The results revealed that the hydrogenotrophic M. maripaludis strain can utilize acetate as an alternative energy source. Corrosion of EH40 steel is initially inhibited, but prolonged exposure with the methanogen leads to an eventual corrosion propagation. During the early stage of immersion in M. maripaludis culture medium, the formation of a protective corrosion products film inhibits EH40 steel corrosion. The presence of M. maripaludis promotes both anodic and cathodic reactions of EH40 steel in the late stage of exposure. Surface analyses revealed that pitting corrosion is closely related to uneven distribution of M. maripaludis biofilm on EH40 steel surface.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bioelechem.2021.107824DOI Listing
April 2021

Microplastic: A potential threat to human and animal health by interfering with the intestinal barrier function and changing the intestinal microenvironment.

Sci Total Environ 2021 Apr 27;785:147365. Epub 2021 Apr 27.

College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310032, China. Electronic address:

Plastics are widely used in many fields due to their stable physical and chemical properties, and their global production and usage increase significantly every year, which leads to the accumulation of microplastics in the entire ecosystem. Numerous studies have shown that microplastics (MPs) have harmful effects on living organisms. This review aims to provide a comprehensive conclusion of the current knowledge of the impacts of MPs on the stability of the gut microenvironment, especially on the gut barrier. Studies showed that exposure to MPs could cause oxidative damage and inflammation in the gut, as well as the destruction of the gut epithelium, reduction of the mucus layer, microbial disorders, and immune cell toxicity. Although there are few reports directly related to humans, we hoped that this review could bring together more and more evidence that exposure to MPs results in disturbances of the intestinal microenvironment. Therefore, it is necessary to investigate their threats to human health further.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.scitotenv.2021.147365DOI Listing
April 2021

Photo-induced mitochondrial DNA damage and NADH depletion by -NO modified Ru(II) complexes.

Chem Commun (Camb) 2021 Apr;57(34):4162-4165

Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.

Two mitochondria-localized Ru(ii) complexes with photo-labile ligands were reported to exert one- and two-photon activatable anticancer activity through a dual-function mechanism, i.e. mitochondrial DNA covalent binding after photo-induced ligand dissociation and photo-catalyzed NADH depletion, thus displaying good activity towards cisplatin-resistant cancer cells under both normoxic and hypoxic conditions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1039/d1cc00258aDOI Listing
April 2021

Graph Learning Based Head Movement Prediction for Interactive 360 Video Streaming.

IEEE Trans Image Process 2021 3;30:4622-4636. Epub 2021 May 3.

Ultra-high definition (UHD) 360 videos encoded in fine quality are typically too large to stream in its entirety over bandwidth (BW)-constrained networks. One popular approach is to interactively extract and send a spatial sub-region corresponding to a viewer's current field-of-view (FoV) in a head-mounted display (HMD) for more BW-efficient streaming. Due to the non-negligible round-trip-time (RTT) delay between server and client, accurate head movement prediction foretelling a viewer's future FoVs is essential. In this paper, we cast the head movement prediction task as a sparse directed graph learning problem: three sources of relevant information-collected viewers' head movement traces, a 360 image saliency map, and a biological human head model-are distilled into a view transition Markov model. Specifically, we formulate a constrained maximum a posteriori (MAP) problem with likelihood and prior terms defined using the three information sources. We solve the MAP problem alternately using a hybrid iterative reweighted least square (IRLS) and Frank-Wolfe (FW) optimization strategy. In each FW iteration, a linear program (LP) is solved, whose runtime is reduced thanks to warm start initialization. Having estimated a Markov model from data, we employ it to optimize a tile-based 360 video streaming system. Extensive experiments show that our head movement prediction scheme noticeably outperformed existing proposals, and our optimized tile-based streaming scheme outperformed competitors in rate-distortion performance.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1109/TIP.2021.3073283DOI Listing
May 2021

Comparison of hematological traits and oxygenation properties of hemoglobins from highland and lowland Asiatic toad (Bufo gargarizans).

J Comp Physiol B 2021 Apr 19. Epub 2021 Apr 19.

Department of Animal and Biomedical Sciences, School of Life Science, Lanzhou University, Lanzhou, 730000, Gansu, China.

The Asiatic toad (Bufo gargarizans) belonging to the family of Bufonidae (Anura: Amphibia) is successfully residing on the Qinghai-Tibetan Plateau (QTP). To investigate whether the oxygen delivery undergoes adaptive adjustments to high-altitude environments in Asian toads inhabiting the QTP (Zoige County, 3446 m), choosing low-altitude populations (Chengdu City, 500 m) as control, we measured hematological traits, O affinities of whole blood, Hb-O affinities of purified Hbs, their sensitivities to temperature, and allosteric effectors (H, Cl and ATP). Our results showed that high-altitude Asiatic toads possessed significantly increased hemoglobin concentration, hematocrit, and red blood cell count, but significantly decreased erythrocyte volume compared with low-altitude toads. The whole blood and purified Hbs of high-altitude Asiatic toads both exhibited significantly higher O affinities compared with low-altitude toads. Substantially increased intrinsic Hb-O affinities of high-altitude Asiatic toads Hbs are likely to be the main reason for its elevated Hb-O affinities given the anionic cofactor sensitivities of high- and low-altitude toads were similar. The Hbs of high-altitude toads were also characterized by distinctly strong Bohr effects at the low temperature and low-temperature sensitivities. The adaptive adjustments of hematological traits could enhance the blood-O carrying capacity of high-altitude Asiatic toads. The increased Hb-O affinities could safeguard the pulmonary O uploading under hypoxia. The strong Bohr effects at the low temperature could help the release of O in metabolic tissues and cold limbs, while low-temperature sensitivity could minimize the effect of temperature fluctuation on the Hb-O affinity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00360-021-01368-8DOI Listing
April 2021

High-throughput screening identifies established drugs as SARS-CoV-2 PLpro inhibitors.

Protein Cell 2021 Apr 17. Epub 2021 Apr 17.

Shanghai Institute for Advanced Immunochemical Studies and School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China.

A new coronavirus (SARS-CoV-2) has been identified as the etiologic agent for the COVID-19 outbreak. Currently, effective treatment options remain very limited for this disease; therefore, there is an urgent need to identify new anti-COVID-19 agents. In this study, we screened over 6,000 compounds that included approved drugs, drug candidates in clinical trials, and pharmacologically active compounds to identify leads that target the SARS-CoV-2 papain-like protease (PLpro). Together with main protease (M), PLpro is responsible for processing the viral replicase polyprotein into functional units. Therefore, it is an attractive target for antiviral drug development. Here we discovered four compounds, YM155, cryptotanshinone, tanshinone I and GRL0617 that inhibit SARS-CoV-2 PLpro with IC values ranging from 1.39 to 5.63 μmol/L. These compounds also exhibit strong antiviral activities in cell-based assays. YM155, an anticancer drug candidate in clinical trials, has the most potent antiviral activity with an EC value of 170 nmol/L. In addition, we have determined the crystal structures of this enzyme and its complex with YM155, revealing a unique binding mode. YM155 simultaneously targets three "hot" spots on PLpro, including the substrate-binding pocket, the interferon stimulating gene product 15 (ISG15) binding site and zinc finger motif. Our results demonstrate the efficacy of this screening and repurposing strategy, which has led to the discovery of new drug leads with clinical potential for COVID-19 treatments.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s13238-021-00836-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8052528PMC
April 2021

Combined hepatotoxicity of imidacloprid and microplastics in adult zebrafish: Endpoints at gene transcription.

Comp Biochem Physiol C Toxicol Pharmacol 2021 Apr 16;246:109043. Epub 2021 Apr 16.

College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310032, China. Electronic address:

Microplastics (MPs) and pesticides are two kinds of ubiquitous pollutants that can pose a health risk to aquatic organisms. However, researches about the combined effects of MPs and pesticides are very limited. A simple combined exposure model was established in this study, adult zebrafish were exposed to 100 μg/L imidacloprid (IMI), 20 μg/L polystyrene microplastics (PS), and a combination of PS and IMI (PS + IMI) for 21 days. The results demonstrated that exposure to PS and IMI inhibited the growth of zebrafish and altered the levels of glycolipid metabolism and oxidative stress-related biochemical parameters. While gene expression analysis revealed that, compared with PS or IMI treatment group, combined exposure caused a greater change in gene expression levels involving the process of glycolipid metabolism (Gk, Hk1, Aco, PPar-α, Cpt1, Acc, Fas, PPar-γ, Apo) and inflammatory response (IL-1β, IL-6, IL-8, TNF-α, IL-10). The results demonstrated that even combined exposure of low concentrations of PS and IMI could cause more severe hepatotoxicity in zebrafish, especially in terms of gene transcription. And more combined toxicity studies are essential for MPs and pesticides risk assessment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cbpc.2021.109043DOI Listing
April 2021

Study Protocol: Design and Implementation of the Pediatric Liver Transplantation Biobank.

Biopreserv Biobank 2021 Apr 12;19(2):111-118. Epub 2021 Apr 12.

Biobank Center of Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Child Infection and Immunity, Chongqing, China.

Early treatment of neonatal biliary atresia (BA) and other end-stage liver diseases can delay or prevent the necessity of liver transplantation (LT). The establishment of a standardized clinical pediatric liver transplantation (PLT) biobank is the prerequisite for scientific research, which helps to provide a qualified sample resource platform for research. Following standardized procedures to establish biobanks, the operational processes and quality control system were formulated. Liver tissue, blood, and stool samples undergoing LT were regularly collected, managed, and stored. Systematic management was conducted in collected specimens and corresponding clinical information. Since implementation in August 2018, we have enrolled 49 unique subjects (0-18 years of age); the biobank contains nearly 3000 biospecimen aliquots. The most common LT diagnosis is BA (61.23%). The establishment of this biobank is a valuable resource that incorporates detailed clinical and biological information. It will help accelerate the pace of PLT discovery research. ClinicalTrials.gov ID: NCT04477967.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1089/bio.2020.0128DOI Listing
April 2021

Jiyuan Oridonin A Overcomes Differentiation Blockade in Acute Myeloid Leukemia Cells With MLL Rearrangements Multiple Signaling Pathways.

Front Oncol 2021 26;11:659720. Epub 2021 Mar 26.

Laboratory for Stem Cell and Regenerative Medicine, Affiliated Hospital of Weifang Medical University, Weifang, China.

Differentiation therapy with all-trans-retinoic acid (ATRA) in acute promyelocytic leukemia (APL), a subtype of acute myeloid leukemia (AML), has been extremely successful in inducing clinical remission in APL patients. However, the differentiation therapy of ATRA-based treatment has not been effective in other subtypes of AML. In this study, we evaluated a small molecule of -kaurene diterpenoid, Jiyuan oridonin A (JOA), on the differentiation blockade in AML cells with the mixed lineage leukemia (MLL) gene rearrangements (MLLr) in MV4-11, MOLM-13 and THP-1 cells. We found that JOA could significantly inhibit the proliferation of MOLM-13, MV4-11 and THP-1 cells. Moreover, JOA promoted cell differentiation coupled with cell-cycle exit at G0/G1 and inhibited the colony- forming capacity of these cells. We showed that the anti-proliferative effect of JOA attributed to cell differentiation is most likely through the martens tretinoin response up pathway in the MOLM-13 cell line, and the hematopoietic cell lineage pathway by the inhibition of c-KIT expression and cell adhesion pathway in the THP-1 cell line. Our findings suggest that JOA could be a novel therapeutic agent against human MLLr acute myeloid leukemia.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fonc.2021.659720DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8033199PMC
March 2021

Effects of polyethylene microplastics on the microbiome and metabolism in larval zebrafish.

Environ Pollut 2021 Mar 31;282:117039. Epub 2021 Mar 31.

College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310032, China. Electronic address:

Various microplastics (MPs) are found in the environment and organisms. MP residues in organisms can affect health; however, their impacts on metabolism in aquatic organisms remain unclear. In this study, zebrafish embryos were exposed to polyethylene MPs with sizes ranging from 1 to 4 μm at concentrations of 0, 10, 100, and 1000 μg/L for 7 days. Through qPCR technology, the results indicated that zebrafish exposed to polyethylene MPs exhibited significant change in microbes of the phyla Firmicutes, Bacteroidetes, Proteobacteria, and Verrucomicrobia, etc. Moreover, 16S RNA gene sequencing revealed that there was a significant difference in alpha diversity between the control and 1000 μg/L MP-treated groups. At the genus level, the abundance of Aeromonas, Shewanella, Microbacterium, Nevskia and Methyloversatilis have increased remarkably. Conversely, the abundance of Pseudomonas, Ralstonia and Stenotrophomonas were significant reduction after MPs exposure. In addition, the levels of TG (triglyceride), TCHO (total cholesterol), NEFA (nonesterified fatty acid), TBA (total bile acid), GLU (glucose) and pyruvic acid significantly changed in MP-treated larval zebrafish, indicating that their metabolism was disturbed by MPs. Transcriptional levels of glucose and lipid metabolism-related genes showed a decreasing trend. Furthermore, LC/MS-based nontargeted metabolomics analysis demonstrated that a total of 59 phospholipid-related substances exhibited significant changes in larval fish treated with 1000 μg/L MPs. The mRNA levels of phospholipid metabolism-related genes were also obviously changed. Pearson correlation analysis indicated that the abundance of Aeromonas, Shewanella and Chitinibacter bacteria showed a negative correlation with most phospholipids, while Nevskia, Parvibacter and Lysobacter showed a positive correlation with most phospholipids. Based on these results, it is suggested that 1-4 μm PE-MPs could impact the microbiome and metabolism of larval zebrafish. All of these results indicated that the health risk of MPs cannot be ignored.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.envpol.2021.117039DOI Listing
March 2021

Evaluation of Adjacent Segment With Pre-Existing Degeneration Using the Cerebrospinal Fluid Occlusion Sign on MRI Before Posterior Lumbar Fusion: A Multi-Center Observational Cohort Study.

Global Spine J 2021 Apr 7:21925682211007116. Epub 2021 Apr 7.

Orthopaedic Department of 105738Beijing Tiantan Hospital, Beijing, China.

Study Design: Prospective cohort study.

Objective: To evaluate whether pre-existing adjacent spinal canal stenosis (SCS) is associated with short-term outcomes after lumbar fusion surgery.

Methods: We included patients with lumbar spinal stenosis treated surgically between July 2015 and December 2017 at 4 centers. All patients had the same pathology, with L4-S1 as the culprit sections. Patients were divided into 2 groups based on the cerebrospinal fluid occlusion sign on MRI at the adjacent L3/4 level. Patients without SCS (grade 0) and with mild SCS (grade 1) were classified into the non-stenosis (NS) and mild stenosis (MS) groups, respectively. All patients underwent PLIF and completed at least 1-year follow-up. The incidence of adjacent segment degeneration (ASDeg) and clinical outcomes were compared between the 2 groups.

Results: A total of 308 patients (NS, 156; MS, 152) met the inclusion criteria. The incidence of ASDeg in the NS group (n = 40, 25.6%) was significantly lower than that in the MS group (n = 74, 48.7%; < .001). The most frequent type of ASDeg in the 2 groups was the SCS-aggravated type. No significant difference was observed in adjacent segment disease incidence between the 2 groups ( = .243). The NS group had better outcomes according to the clinical function scores ( < .05).

Conclusions: The cerebrospinal fluid occlusion sign on MRI is valuable for evaluating the adjacent segment with pre-existing degeneration. Patients with mild SCS in adjacent segments were more likely to have ASDeg, and the most frequent type of ASDeg was the SCS-aggravated type at early follow-up.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1177/21925682211007116DOI Listing
April 2021

Efficient photocatalytic hydrogen peroxide generation coupled with selective benzylamine oxidation over defective ZrS nanobelts.

Nat Commun 2021 04 1;12(1):2039. Epub 2021 Apr 1.

Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, Singapore.

Photocatalytic hydrogen peroxide (HO) generation represents a promising approach for artificial photosynthesis. However, the sluggish half-reaction of water oxidation significantly limits the efficiency of HO generation. Here, a benzylamine oxidation with more favorable thermodynamics is employed as the half-reaction to couple with HO generation in water by using defective zirconium trisulfide (ZrS) nanobelts as a photocatalyst. The ZrS nanobelts with disulfide (S) and sulfide anion (S) vacancies exhibit an excellent photocatalytic performance for HO generation and simultaneous oxidation of benzylamine to benzonitrile with a high selectivity of >99%. More importantly, the S and S vacancies can be separately introduced into ZrS nanobelts in a controlled manner. The S vacancies are further revealed to facilitate the separation of photogenerated charge carriers. The S vacancies can significantly improve the electron conduction, hole extraction, and kinetics of benzylamine oxidation. As a result, the use of defective ZrS nanobelts yields a high production rate of 78.1 ± 1.5 and 32.0 ± 1.2 μmol h for HO and benzonitrile, respectively, under a simulated sunlight irradiation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41467-021-22394-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8016833PMC
April 2021

NUPR1 participates in YAP-mediate gastric cancer malignancy and drug resistance via AKT and p21 activation.

J Pharm Pharmacol 2021 Apr;73(6):740-748

General Surgery, The Affiliated Huaian No. 1 People's Hospital of Nanjing Medical University, Huai'an City, Jiangsu Province, China.

Objectives: To assess nuclear protein 1 (NUPR1) level in human gastric cancer (GC) cells, explore the effects of NUPR1 on GC progression, and investigate the possible regulatory mechanism.

Methods: Immunohistochemistry (IHC), Immunoblot and quantitative PCR assays were conducted to detect the NUPR1 level in human GC tissues and corresponding normal tissues. Also, NUPR1 expression level correlates with clinical features of GC patients. 3-(4,5-Dimethylthiazol-2-Yl)-2,5-Diphenyltetrazolium Bromide (MTT), transwell assays, Immunoblot assays, and flow cytometry (FCM) assays were used to evaluate the effects of NUPR1 on the proliferation, invasion, epithelial-mesenchymal transformation (EMT) and apoptosis of GC cells in vitro. Immunoblot assays were performed to detect the potential mechanism in NUPR1-mediated drug resistance.

Key Findings: We found the expression of NUPR1 was upregulated in human gastric cancer tissues and correlated with the clinical features including tumour size, tumour stage and, lymph node metastasis. We further noticed that the depletion of NUPR1 inhibited the invasion and EMT of gastric cancer cells and stimulated the apoptosis. In doxorubicin-resistant gastric cancer cells, yes-associated protein (YAP) activation was up-regulated, and YAP could regulate the expression of NUPR1 to affect drug-resistance. We further provided the evidence that overexpression of NUPR1 reversed the effect of YAP knockdown on cell malignancy and drug resistance via regulating AKT and p21 pathway.

Conclusions: Our findings indicated the involvement of NUPR1 in the progression of gastric cancer and elucidated its molecular mechanism in regulating drug resistance.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/jpp/rgab010DOI Listing
April 2021

Ephrin-A2 promotes prostate cancer metastasis by enhancing angiogenesis and promoting EMT.

J Cancer Res Clin Oncol 2021 Mar 27. Epub 2021 Mar 27.

Medical Technology School of Xuzhou Medical University, Xuzhou, 221004, China.

Background: Ephrin-A2, a member of the Eph receptor subgroup, is used in diagnosing and determining the prognosis of prostate cancer. However, the role of ephrin-A2 in prostate cancer is remains elusive.

Methods: We established stable clones overexpressing or silencing ephrin-A2 from prostate cancer cells. Then, CCK-8 was used in analyzing the proliferation ability of cells. CD31 staining was used in evaluating angiogenesis. Migration and invasion assay were conducted in vivo and in vitro. The expression of EMT-related markers was evaluated in prostate cancer cells through Western blotting.

Results: We revealed that the ectopic expression of ephrin-A2 in prostate cancer cells facilitated cell migration and invasion in vitro and promoted tumor metastasis and angiogenesis in vivo and that the silencing of ephrin-A2 completely reversed this effect. Although ephrin-A2 did not affect tumor cell proliferation in vitro, ephrin-A2 significantly promoted primary tumor growth in vivo. Furthermore, to determine the biological function of ephrin-A2, we assayed the expression of EMT-related markers in stable-established cell lines. Results showed that the overexpression of ephrin-A2 in prostate cancer cells down-regulated the expression of epithelial markers (ZO-1, E-cadherin, and claudin-1) and up-regulated the expression of mesenchymal markers (N-cadherin, β-catenin, vimentin, Slug, and Snail), but the knocking out of ephrin-A2 opposed the effects on the expression of EMT markers.

Conclusions: These findings indicate that ephrin-A2 promotes prostate cancer metastasis by enhancing angiogenesis and promoting EMT and may be a potentially therapeutic target in metastatic prostate cancer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00432-021-03618-2DOI Listing
March 2021

OGP46 Induces Differentiation of Acute Myeloid Leukemia Cells via Different Optimal Signaling Pathways.

Front Cell Dev Biol 2021 4;9:652972. Epub 2021 Mar 4.

Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, St. John's University, New York, NY, United States.

Acute myelogenous leukemia (AML) is characterized by blockage of cell differentiation leading to the accumulation of immature cells, which is the most prevalent form of acute leukemia in adults. It is well known that all-trans retinoic acid (ATRA) and arsenic trioxide (ATO) are the preferred drugs for acute promyelocytic leukemia (APL). However, they can lead to irreversible resistance which may be responsible for clinical failure after complete remission (CR). Moreover, the differentiation therapy of ATRA-based treatment has not been effective against AML with t(8;21) translocation. Here we aimed to identify the differentiation effect of OGP46 on AML cell lines (HL-60, NB4, and Kasumi-1) and explore its possible mechanisms. We found that OGP46 has significant inhibitory activity against these cells by triggering cell differentiation with cell-cycle exit at G1/G0 and inhibited the colony-formation capacity of the AML cells. It was shown that OGP46 induced the differentiation of NB4 cells via the transcriptional misregulation in cancer signaling pathway by PML-RARα depletion, while it was attributed to the hematopoietic cell lineage and phagosome pathway in Kasumi-1 cells, which are all critical pathways in cell differentiation. These results highlight that OGP46 is an active agent not only in the APL cell line NB4 but also in AML-M2 cell lines, especially Kasumi-1 with t(8;21) translocation. Therefore, OGP46 may be a potential compound for surmounting the differentiation blockage in AML.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fcell.2021.652972DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7969801PMC
March 2021

Degradation of poly(butylene adipate-co-terephthalate) by Stenotrophomonas sp. YCJ1 isolated from farmland soil.

J Environ Sci (China) 2021 May 28;103:50-58. Epub 2020 Oct 28.

School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi'an 170021, China.

In recent years, poly (butylene adipate-co-terephthalate) (PBAT) has been widely used. However, PBAT-degrading bacteria have rarely been reported. PBAT-degrading bacteria were isolated from farmland soil and identified. The effects of growth factors on the degradation of PBAT and the lipase activity of PBAT-degrading bacteria were assessed. The degradation mechanism was analyzed using scanning electron microscopy, attenuated total reflection Fourier transform infrared spectroscopy, proton nuclear magnetic resonance, X-ray diffraction, and liquid chromatography-mass spectrometry. The results showed that Stenotrophomonas sp. YCJ1 had a significant degrading effect on PBAT. Under certain conditions, the strain could secrete 10.53 U/mL of lipase activity and degrade 10.14 wt.% of PBAT films. The strain secreted lipase to catalyze the degradation of the ester bonds in PBAT, resulting in the production of degradation products such as terephthalic acid, 1,4-butanediol, and adipic acid. Furthermore, the degradation products could participate in the metabolism of YCJ1 as carbon sources to facilitate complete degradation of PBAT, indicating that the strain has potential value for the bioremediation of PBAT in the environment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jes.2020.10.001DOI Listing
May 2021

A Near-Infrared-II Polymer with Tandem Fluorophores Demonstrates Superior Biodegradability for Simultaneous Drug Tracking and Treatment Efficacy Feedback.

ACS Nano 2021 03 9;15(3):5428-5438. Epub 2021 Mar 9.

Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry Chinese Academy of Sciences, Beijing 100190, China.

NIR-II (1000-1700 nm) fluorescence imaging is continually attracting strong research interest. However, current NIR-II imaging materials are limited to small molecules with fast blood clearance and inorganic nanomaterials and organic conjugated polymers of poor biodegradability and low biocompatibility. Here, we report a highly biodegradable polyester carrying tandem NIR-II fluorophores as a promising alternative. The polymer encapsulated a platinum intercalator (56MESS, (5,6-dimethyl-1,10-phenanthroline) (1,2-diaminocyclohexane) platinum(II)) and was conjugated with both a cell-targeting RGD peptide and a caspase-3 cleavable peptide probe to form nanoparticles for simultaneous NIR-II and apoptosis imaging. , the nanoparticles were approximately 4-1000- and 1.5-10-fold more potent than cisplatin and 56MESS, respectively. Moreover, , they significantly inhibited tumor growth on a multidrug-resistant patient-derived mouse model (PDX). Finally, through label-free laser desorption-ionization mass spectrometry imaging (MALDI-MSI), 56MESS release in the deeper tumors was observed. This work highlighted the use of biodegradable NIR-II polymers for monitoring drugs and therapeutic effect feedback in real-time.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acsnano.1c00076DOI Listing
March 2021

effector Avr1d functions as an E2 competitor and inhibits ubiquitination activity of GmPUB13 to facilitate infection.

Proc Natl Acad Sci U S A 2021 Mar;118(10)

Department of Plant Pathology, Nanjing Agricultural University, 210095 Nanjing, China;

Oomycete pathogens such as secrete a repertoire of effectors into host cells to manipulate host immunity and benefit infection. In this study, we found that an RxLR effector, Avr1d, promoted infection in soybean hairy roots. Using a yeast two-hybrid screen, we identified the soybean E3 ubiquitin ligase GmPUB13 as a host target for Avr1d. By coimmunoprecipitation (Co-IP), gel infiltration, and isothermal titration calorimetry (ITC) assays, we confirmed that Avr1d interacts with GmPUB13 both in vivo and in vitro. Furthermore, we found that Avr1d inhibits the E3 ligase activity of GmPUB13. The crystal structure Avr1d in complex with GmPUB13 was solved and revealed that Avr1d occupies the binding site for E2 ubiquitin conjugating enzyme on GmPUB13. In line with this, Avr1d competed with E2 ubiquitin conjugating enzymes for GmPUB13 binding in vitro, thereby decreasing the E3 ligase activity of GmPUB13. Meanwhile, we found that inactivation of the ubiquitin ligase activity of GmPUB13 stabilized GmPUB13 by blocking GmPUB13 degradation. Silencing of GmPUB13 in soybean hairy roots decreased infection, suggesting that GmPUB13 acts as a susceptibility factor. Altogether, this study highlights a virulence mechanism of effectors, by which Avr1d competes with E2 for GmPUB13 binding to repress the GmPUB13 E3 ligase activity and thereby stabilizing the susceptibility factor GmPUB13 to facilitate infection. This study unravels the structural basis for modulation of host targets by effectors and will be instrumental for boosting plant resistance breeding.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1073/pnas.2018312118DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7958378PMC
March 2021

A Deep Ordinal Distortion Estimation Approach for Distortion Rectification.

IEEE Trans Image Process 2021 5;30:3362-3375. Epub 2021 Mar 5.

Radial distortion has widely existed in the images captured by popular wide-angle cameras and fisheye cameras. Despite the long history of distortion rectification, accurately estimating the distortion parameters from a single distorted image is still challenging. The main reason is that these parameters are implicit to image features, influencing the networks to learn the distortion information fully. In this work, we propose a novel distortion rectification approach that can obtain more accurate parameters with higher efficiency. Our key insight is that distortion rectification can be cast as a problem of learning an ordinal distortion from a single distorted image. To solve this problem, we design a local-global associated estimation network that learns the ordinal distortion to approximate the realistic distortion distribution. In contrast to the implicit distortion parameters, the proposed ordinal distortion has a more explicit relationship with image features, and significantly boosts the distortion perception of neural networks. Considering the redundancy of distortion information, our approach only uses a patch of the distorted image for the ordinal distortion estimation, showing promising applications in efficient distortion rectification. In the distortion rectification field, we are the first to unify the heterogeneous distortion parameters into a learning-friendly intermediate representation through ordinal distortion, bridging the gap between image feature and distortion rectification. The experimental results demonstrate that our approach outperforms the state-of-the-art methods by a significant margin, with approximately 23% improvement on the quantitative evaluation while displaying the best performance on visual appearance.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1109/TIP.2021.3061283DOI Listing
March 2021

MiRNA-621 exerts tumor suppressor function in gastric adenocarcinoma by targeting AURKA/GSK-3β pathway.

Acta Biochim Pol 2021 Feb;68(1):91-98

Department of Gastrointestinal Surgery, the Affiliated Huaian No.1 People's Hospital of Nanjing Medical University, Huai 'an, Jiangsu Province, 223001, China.

Gastric adenocarcinoma is a major challenge to human health worldwide. Abnormal expression of miR-621 was found in many types of cancer. This research aimed to investigate the effects and detailed molecular mechanisms of miR-621 on gastric adenocarcinoma progression. The present study first showed that miR-621 was downregulated in gastric cancer patients, and its expression level was correlated with tumor size. MiR-621 overexpression inhibited viability, colony formation and proliferation of gastric cancer cells. AURKA was identified as a direct target of miR-621. AURKA knockdown induced decrease of p-GSK-3β/GSK-3β ratio and increase of p-β-catenin/β-catenin ratio which confirmed that AURKA positively regulated GSK-3β phosphorylation. AURKA knockdown also inhibited proliferation of gastric adenocarcinoma cells. AURKA expression was negatively correlated with miR-621 level. In addition, AURKA overexpression reversed the effect of miR-621 on the growth of cancer cells. Taken together, our results suggest that miR-621 is an important tumor suppressor in gastric cancer and could be a promising target for the cancer treatment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.18388/abp.2020_5452DOI Listing
February 2021

The role of resting respiratory sinus arrhythmia in the family functioning-internet addiction symptoms link.

Int J Psychophysiol 2021 Jun 13;164:17-22. Epub 2021 Feb 13.

Jiangsu Key Laboratory of Mental Health and Cognitive Science, School of Psychology, Nanjing Normal University, China.

Background: Respiratory sinus arrhythmia (RSA) has been understood as a physiological marker of emotional regulatory capacity. To date, little is known about the potential psychophysiological contributions to which influence the family functioning on young adult's internet addiction (IA) symptoms. The aim of this research was to examine the moderating role of resting RSA and its link between family functioning and IA symptoms.

Method: One-hundred and nine participants (69 men) aged between 17 and 21 years old completed questionnaires on family functioning and IA symptoms. Data pertaining to RSA was collected during a resting period in the laboratory.

Results: Resting RSA moderated the association between family functioning and IA symptoms. Specifically, poorer family functioning was related to higher levels of IA symptoms particularly for participants with low resting RSA. When the participants' resting RSA was high, family functioning showed no significant relation with IA symptoms.

Conclusion: Our findings indicated that lower resting RSA may place young adults at greater risk for IA symptoms. This occurs when exposed to poorer family functioning. Furthermore, high resting RSA may serve as a protective factor that alleviates the detrimental influences of poor family functioning on IA symptoms. These findings highlight that contemporaneous consideration is needed for both contextual and physiological factors. This can help to advance persons understanding of internet addictive behaviors in young adults.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ijpsycho.2021.02.012DOI Listing
June 2021

Clinical Parameters of Silent Corticotroph Adenomas With Positive and Negative Adrenocorticotropic Hormone Immunostaining: A Large Retrospective Single-Center Study of 105 Cases.

Front Endocrinol (Lausanne) 2020 18;11:608691. Epub 2021 Jan 18.

Department of Neurosurgery, Shanghai Huashan Institute of Neurological Surgery, Huashan Hospital, Shanghai Medical School, Fudan University, Shanghai, China.

Purpose: To investigate the different clinical characteristics of silent corticotroph adenomas (SCAs) with positive and negative adrenocorticotropic hormone (ACTH) immunostaining, and to explore the value of pituitary-restricted transcription factor (Tpit) immunostaining for diagnosing SCAs.

Methods: The clinical materials of patients with SCAs who had a typical pathological feature with positive Tpit immunostaining and positive/negative ACTH immunostaining, and without clinical features and biochemical evidence for Cushing's Syndrome in our center from April 2018 to March 2019 were analyzed retrospectively. The differences in clinical characteristics and surgical results between ACTH-positive and -negative SCAs were explored.

Results: A total of one hundred and five patients (94.3% female) with SCAs were included. There were 66 SCAs with ACTH-negative (66/105, 62.9%), and 39 SCAs with ACTH-positive (39/105, 37.1%). Cases with ACTH-negative SCAs were more likely to have lower ACTH levels (27.5 ± 24.0 vs. 54.4 ± 58.6, P = 0.011), more multiple microcysts (81.8% vs. 61.5%, P = 0.022) and lower levels of Ki-67 expression (low expression rate 90.9% vs. 74.4%, P = 0.023). No statistical significant differences were observed between patients with ACTH-positive and -negative SCAs regarding gender (97.0% vs. 89.7%, P = 0.192), age (50.3 ± 10.3 vs. 49.0 ± 11.2, P = 0.543), surgical history (16.7% vs. 23.1%, P = 0.419), suprasellar extension (66.7% vs. 74.4%, P = 0.408), sphenoid sinus extension (51.5% vs. 56.4%, P = 0.627), cavernous sinus invasion (75.8% vs. 66.7%, P = 0.314), large cyst on Magnetic Resonance Imaging (MRI) (47.0% vs. 61.5%, P = 0.149), or gross total resection rate (42.4% vs. 51.3%, P = 0.379).

Conclusions: ACTH-negative SCAs were observed to be more clinically silent and more likely to demonstrate multiple microcysts on MRI. The prevalence of SCAs, especially ACTH-negative SCAs, proved to be substantially underestimated and thus they should be given enough attention in consideration of the high aggressiveness of this subtype of refractory pituitary adenoma (PA).
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fendo.2020.608691DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7873875PMC
January 2021

Deep learning radiomics model accurately predicts hepatocellular carcinoma occurrence in chronic hepatitis B patients: a five-year follow-up.

Am J Cancer Res 2021 1;11(2):576-589. Epub 2021 Feb 1.

Department of Ultrasound, The Third Affiliated Hospital of Sun Yat-Sen University 600 Tianhe Road, Guangzhou, China.

An early and accurate prediction of hepatocellular carcinoma (HCC) is beneficial for individualized treatment and follow-up of chronic hepatitis B (CHB) patients. We aimed to establish a prediction model for HCC by radiomics analysis in CHB patients and compare performance with liver stiffness measurement (LSM) and other clinical prognostic scores. Initially, 1215 patients were included and finally 434 CHB patients with 5-year follow-up were enrolled, 96.3% of them underwent liver biopsy. Deep learning radiomics analysis was performed on 2170 two-dimensional shear wave elastography (2D-SWE) and corresponding B-mode ultrasound (US) images. These high-throughput imaging features were also combined with low-dimensional serological clinical data by deep learning radiomics to establish different HCC prediction models and to overcome challenges of an unbalanced sample. The best model which is simple with high accuracy was selected. Prediction performance of the selected model was compared with LSM and other clinical prognostic scores. During 5-year follow-up, 32 (7.4%) of 434 patients developed HCC. The best prediction model was HCC-R, which included 2D-SWE and B-mode US images, sex and age. This model showed a high predictive value with areas under the receiver operating characteristic curve (AUCs) of 0.981, 0.942 and 0.900 in training, validation and testing cohorts for predicting 5-year prognosis of HCC. These predictive values were significantly higher than that of LSM (AUC: 0.676~0.784, p < 0.05) and better than that of other clinical prognostic scores (AUC: 0.544~0.869). HCC-R radiomics model based on 2D-SWE and B-mode US images, sex and age comprehensively reflected biomechanical and morphological information of patients and can accurately predict HCC occurrence; thus, this model has great value for treatment and follow-up of CHB patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7868753PMC
February 2021

Efficacy and Safety of Anlotinib Combined with Liposomal Doxorubicin Followed by Anlotinib Maintenance in Metastatic Soft Tissue Sarcomas.

Cancer Manag Res 2021 4;13:1009-1016. Epub 2021 Feb 4.

Department of Radiation Oncology, The Affiliated Cancer Hospital of Zhengzhou University and Henan Cancer Hospital, Zhengzhou, Henan, People's Republic of China.

Purpose: Anlotinib is a novel tyrosine kinase inhibitor with promising anti-tumor activity in patients with advanced soft tissue sarcomas (STS) in China. Liposomal doxorubicin monotherapy showed an encouraging effect on this disease. The aim of this study was to evaluate the efficacy and safety of anlotinib combined with liposomal doxorubicin followed by anlotinib maintenance in patients with metastatic STS.

Patients And Methods: This is a multicenter, retrospective, observational study. We reviewed 27 patients with metastatic STS from July 2018 to December 2019, who were treated with anlotinib combined with liposomal doxorubicin followed by anlotinib maintenance in the absence of the tumor progression or intolerable adverse events (AEs).

Results: Of the 27 patients included, 2 patients had complete response (CR), 9 patients obtained partial response (PR), 11 patients achieved stable disease (SD). The objective response rate was 40.7%, the disease control rate was 81.5%, and the median progression-free survival (PFS) was 7 months (95% CI, 5.3-8.1 months). The progression-free rate (PFR) at 3 and 6 months was 81.5% and 59.3%, respectively. Most AEs were mild and acceptable. The most frequent grade 3/4 AEs were leukopenia (33.3%), febrile neutropenia (7.4%), and anemia (7.4%). No deaths related to the treatment were reported.

Conclusion: This study shows that anlotinib combined with liposomal doxorubicin followed by anlotinib maintenance is effective in patients with metastatic STS, and most AEs of this combined therapy are mild and acceptable. Further investigation on its efficacy is warranted.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2147/CMAR.S286322DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7871875PMC
February 2021

Curcumin protects against cognitive impairments in a rat model of chronic cerebral hypoperfusion combined with diabetes mellitus by suppressing neuroinflammation, apoptosis, and pyroptosis.

Int Immunopharmacol 2021 Apr 3;93:107422. Epub 2021 Feb 3.

Department of Neurology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, 600 Yishan Road, Shanghai 200233, China; Shanghai Key Laboratory of Sleep Disordered Breathing, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China. Electronic address:

Background: Chronic cerebral hypoperfusion (CCH) is regarded as a high-risk factor for cognitive decline in vascular dementia (VaD). We have previously shown that diabetes mellitus (DM) synergistically promotes CCH-induced cognitive dysfunction via exacerbating neuroinflammation. Furthermore, curcumin has been shown to exhibit anti-inflammatory and neuroprotective activities. However, the effects of curcumin on CCH-induced cognitive impairments in DM have remained unknown.

Methods: Rats were fed with a high-fat diet (HFD) and injected with low-dose streptozotocin (STZ), followed by bilateral common carotid artery occlusion (BCCAO), to model DM and CCH in vivo. After BCCAO, curcumin (50 mg/kg) was administered intraperitoneally every two days for eight weeks to evaluate its therapeutic effects. Additionally, mouse BV2 microglial cells were exposed to hypoxia and high glucose to model CCH and DM pathologies in vitro.

Results: Curcumin treatment significantly improved DM/CCH-induced cognitive deficits and attenuated neuronal cell death. Molecular analysis revealed that curcumin exerted protective effects via suppressing neuroinflammation induced by microglial activation, regulating the triggering receptor expressed on myeloid cells 2 (TREM2)/toll-like receptor 4 (TLR4)/nuclear factor-κB (NF-κB) pathway, alleviating apoptosis, and reducing nod-like receptor protein 3 (NLRP3)-dependent pyroptosis.

Conclusions: Taken together, our findings suggest that curcumin represents a promising therapy for DM/CCH-induced cognitive impairments.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.intimp.2021.107422DOI Listing
April 2021

Efficient Multiple Biomedical Events Extraction Via Reinforcement Learning.

Bioinformatics 2021 Jan 25. Epub 2021 Jan 25.

Institute of Information Engineering, Chinese Academy of Sciences, Beijing, China.

Motivation: Multiple events extraction from biomedical literature is a challenging task for biomedical community. Usually, biomedical event extraction is modeled as two sub-tasks, trigger identification and argument detection. Most existing methods perform these two sub-tasks sequentially, and fail to make full use of the interaction between them, leading to suboptimal results for multiple biomedical events extraction.

Method: We propose a novel framework of reinforcement learning (RL) for the task of multiple biomedical events extraction. More specifically, trigger identification and argument detection are treated as main-task and subsidiary-task, respectively. Assigning the event type of triggers (in the main-task) is viewed as the action taken in RL, and the result of corresponding argument detection (i.e. the subsidiary-task) for the identified trigger is used for computing the reward of the taken action. Moreover, the result of the subsidiary-task is modeled as part of environment information in RL to help the procedure of trigger identification. In addition, external biomedical knowledge bases are employed for representation learning of biomedical text, which can improve the performance of biomedical event extraction.

Results: Results on two widely used biomedical corpora demonstrate that the proposed framework performs better than the selected baselines on the task of multiple events extraction. The ablation test indicates the contributions of RL and external KBs to the performance improvement in the proposed method. In addition, by modeling multiple events extraction under the RL framework, the supervised information is exploited more effectively than the classical supervised learning paradigm.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/bioinformatics/btab024DOI Listing
January 2021

Open-flow microperfusion combined with mass spectrometry for in vivo liver lipidomic analysis.

Analyst 2021 Mar 22;146(6):1915-1923. Epub 2021 Jan 22.

Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center for Excellence in Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry Chinese Academy of Sciences, Beijing Mass Spectrum Center, Beijing 100190, China.

At present, conventional microdialysis (MD) techniques cannot efficiently sample lipids in vivo, possibly due to the high mass transfer resistance and/or the serious adsorption of lipids onto the semi-permeable membrane of a MD probe. The in vivo monitoring of lipids could be of great significance for the study of disease development and mechanisms. In this work, an open-flow microperfusion (OFM) probe was fabricated, and the conditions for sampling lipids via OFM were optimized. Using OFM, the recovery of lipid standards was improved to more than 34.7%. OFM is used for the in vivo sampling of lipids in mouse liver tissue with fibrosis, and it is then combined with mass spectrometry (MS) to perform lipidomic analysis. 156 kinds of lipids were identified in the dialysate collected via OFM, and it was found that the phospholipid levels, including PC, PE, and SM, were significantly higher in a liver suffering from fibrosis. For the first time, OFM combined with MS to sample and analyze lipids has provided a promising platform for in vivo lipidomic studies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1039/d0an02189jDOI Listing
March 2021

Training deep-learning segmentation models from severely limited data.

Med Phys 2021 Apr 19;48(4):1697-1706. Epub 2021 Feb 19.

Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.

Purpose: To enable generation of high-quality deep learning segmentation models from severely limited contoured cases (e.g., ~10 cases).

Methods: Thirty head and neck computed tomography (CT) scans with well-defined contours were deformably registered to 200 CT scans of the same anatomic site without contours. Acquired deformation vector fields were used to train a principal component analysis (PCA) model for each of the 30 contoured CT scans by capturing the mean deformation and most prominent variations. Each PCA model can produce an infinite number of synthetic CT scans and corresponding contours by applying random deformations. We used 300, 600, 1000, and 2000 synthetic CT scans and contours generated from one PCA model to train V-Net, a 3D convolutional neural network architecture, to segment parotid and submandibular glands. We repeated the training using same numbers of training cases generated from 7, 10, 20, and 30 PCA models, with the data distributed evenly between each PCA model. Performance of the segmentation models was evaluated with Dice similarity coefficients between auto-generated contours and physician-drawn contours on 162 test CT scans for parotid glands and another 21 test CT scans for submandibular glands.

Results: Dice values varied with the number of synthetic CT scans and the number of PCA models used to train the network. By using 2000 synthetic CT scans generated from 10 PCA models, we achieved Dice values of 82.8% ± 6.8% for right parotid, 82.0% ± 6.9% for left parotid, and 74.2% ± 6.8% for submandibular glands. These results are comparable with those obtained from state-of-the-art auto-contouring approaches, including a deep learning network trained from more than 1000 contoured patients and a multi-atlas algorithm from 12 well-contoured atlases. Improvement was marginal when >10 PCA models or >2000 synthetic CT scans were used.

Conclusions: We demonstrated an effective data augmentation approach to train high-quality deep learning segmentation models from a limited number of well-contoured patient cases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/mp.14728DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8058262PMC
April 2021

The complete chloroplast genome of (Orchidaceae), a rare and ornamental orchid.

Mitochondrial DNA B Resour 2020 Nov 13;5(3):3746-3747. Epub 2020 Nov 13.

Department of Biodiversity Conservation, Southwest Forestry University, Kunming, China.

The genus of Lindl. comprised about 200 species while its generic relationship has been uncertain. The whole chloroplast genome of was reported in order to provide new data on the molecular phylogeny of . The cp genome of was 1,600,93 bp in total length, including a pair of inverted repeat regions (IR, 26,710 bp), one large single-copy region (LSC, 87,868 bp), and one small single-copy region (SSC, 188,05 bp). The complete chloroplast DNA encoded 132 genes, containing 86 protein-coding genes, 38 tRNA genes, and eight rRNA genes. Phylogenetic analysis showed that was related to .
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/23802359.2020.1835569DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7671590PMC
November 2020