Publications by authors named "Fang Zheng"

779 Publications

Total Glucosides of Paeony Ameliorate Pristane-Induced Lupus Nephritis by Inducing PD-1 ligands Macrophages Activating IL-4/STAT6/PD-L2 Signaling.

Front Immunol 2021 5;12:683249. Epub 2021 Jul 5.

Section of Immunology & Joint Immunology Program, Guangdong Provincial Academy of Chinese Medical Sciences, Guangzhou, China.

Macrophages, a major subset of innate immune cells, are main infiltrating cells in the kidney in lupus nephritis. Macrophages with different phenotypes exert diverse or even opposite effects on the development of lupus nephritis. Substantial evidence has shown that macrophage M2 polarization is beneficial to individuals with chronic kidney disease. Further, it has been reported that PD-1 ligands (PD-Ls) contribute to M2 polarization of macrophages and their immunosuppressive effects. Total glucosides of paeony (TGP), originally extracted from Radix Paeoniae Alba, has been approved in China to treat some autoimmune diseases. Here, we investigated the potentially therapeutic effects of TGP on lupus nephritis in a pristane-induced murine model and explored the molecular mechanisms regulating macrophage phenotypes. We found that TGP treatment significantly improved renal function by decreasing the urinary protein and serum creatinine, reducing serum anti-ds-DNA level and ameliorating renal immunopathology. TGP increased the frequency of splenic and peritoneal F4/80CD11bCD206 M2-like macrophages with no any significant effect on F4/80CD11bCD86 M1-like macrophages. Immunofluorescence double-stainings of the renal tissue showed that TGP treatment increased the frequency of F4/80Arg1 subset while decreasing the percentage of F4/80iNOS subset. Importantly, TGP treatment increased the percentage of both F4/80CD11bPD-L1 and F4/80CD11bPD-L2 subsets in spleen and peritoneal lavage fluid as well as the kidney. Furthermore, TGP augmented the expressions of CD206, PD-L2 and phosphorylated STAT6 in IL-4-treated Raw264.7 macrophages while its effects on PD-L2 were abolished by pretreatment of the cells with an inhibitor of STAT6, AS1517499. However, TGP treatment did not affect the expressions of STAT1 and PD-L1 in Raw264.7 macrophages treated with LPS/IFN-γ , indicating a possibly indirect effect of TGP on PD-L1 expression on macrophages . Thus, for the first time, we demonstrated that TGP may be a potent drug to treat lupus nephritis by inducing F4/80CD11bCD206 and F4/80CD11bPD-L2 macrophages through IL-4/STAT6/PD-L2 signaling pathway.
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http://dx.doi.org/10.3389/fimmu.2021.683249DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8288191PMC
July 2021

Microfluidic synthesis of pyrrolidin-2-ones photoinduced organocatalyzed cyclization of styrene, α-bromoalkyl esters and primary amines.

Org Biomol Chem 2021 Jul 8. Epub 2021 Jul 8.

College of Biotechnology and Pharmaceutical Engineering Nanjing Tech University, 30 Puzhu Rd S., Nanjing, 211816, China. and State Key Laboratory of Materials-Oriented Chemical Engineering, 30 Puzhu Rd S., Nanjing, 211816, China.

A green and efficient reaction route for the synthesis of pyrrolidin-2-ones via photoinduced organocatalyzed three-component cyclization of styrene, tertiary α-bromoalkyl esters and primary amines in a microchannel reactor under visible light conditions has been developed. Moreover, the overall process can be carried out under mild conditions without using a metal. In addition, a reasonable reaction mechanism was proposed based on control experiments.
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http://dx.doi.org/10.1039/d1ob01082dDOI Listing
July 2021

Radiomics Score Combined with ACR TI-RADS in Discriminating Benign and Malignant Thyroid Nodules Based on Ultrasound Images: A Retrospective Study.

Diagnostics (Basel) 2021 Jun 1;11(6). Epub 2021 Jun 1.

Department of Ultrasound, The Second Affiliated Hospital of Chongqing Medical University, Chongqing 400010, China.

This study aimed to explore the ability of combination model of ultrasound radiomics score (Rad-score) and the thyroid imaging, reporting and data system by the American College of Radiology (ACR TI-RADS) in predicting benign and malignant thyroid nodules (TNs). Up to 286 radiomics features were extracted from ultrasound images of TNs. By using the lowest probability of classification error and average correlation coefficients (POE + ACC) and the least absolute shrinkage and selection operator (LASSO), we finally selected four features to establish Rad-score (Vertl-RLNonUni, Vertl-GLevNonU, WavEnLH-s4 and WavEnHL-s5). DeLong's test and decision curve analysis (DCA) showed that the method of combining Rad-score and ACR TI-RADS had the best performance (the area under the receiver operating characteristic curve (AUC = 0.913 (95% confidence interval (CI), 0.881-0.939) and 0.899 (95%CI, 0.840-0.942) in the training group and verification group, respectively), followed by ACR TI-RADS (AUC = 0.898 (95%CI, 0.863-0.926) and 0.870 (95%CI, 0.806-0.919) in the training group and verification group, respectively), and followed by Rad-score (AUC = 0.750 (95%CI, 0.704-0.792) and 0.750 (95%CI, 0.672-0.817) in the training group and verification group, respectively). We concluded that the ability of ultrasound Rad-score to distinguish benign and malignant TNs was not as good as that of ACR TI-RADS, and the ability of the combination model of Rad-score and ACR TI-RADS to discriminate benign and malignant TNs was better than ACR TI-RADS or Rad-score alone. Ultrasound Rad-score might play a potential role in improving the differentiation of malignant TNs from benign TNs.
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http://dx.doi.org/10.3390/diagnostics11061011DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8229428PMC
June 2021

An Electrochemical Route for Special Oxidative Ring-Opening of Indoles.

Chemistry 2021 Jun 29. Epub 2021 Jun 29.

Nanjing Tech University, College of Biotechnology and Pharmaceutical Engineering, CHINA.

A novel electrochemical protocol for the oxidative cleavage of indoles has been developed, which offers a simple way to access synthetically useful anthranilic acid derivatives. In undivided cells, a wide variety of indoles and alcohol compounds are examined to afford amide ester aromatics without using extra oxidants and stoichiometric metal catalysts, which avoids the formation of undesired by-products and exhibits high atom economy. The products we described in this perspective represent synthetic intermediate in numerous drug molecules and industrial chemical reagents and remarkably shows potential application in future.
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http://dx.doi.org/10.1002/chem.202101527DOI Listing
June 2021

Transcriptional Start Site Coverage Analysis in Plasma Cell-Free DNA Reveals Disease Severity and Tissue Specificity of COVID-19 Patients.

Front Genet 2021 28;12:663098. Epub 2021 May 28.

BGI-Shenzhen, Shenzhen, China.

Symptoms of coronavirus disease 2019 (COVID-19) range from asymptomatic to severe pneumonia and death. A deep understanding of the variation of biological characteristics in severe COVID-19 patients is crucial for the detection of individuals at high risk of critical condition for the clinical management of the disease. Herein, by profiling the gene expression spectrum deduced from DNA coverage in regions surrounding transcriptional start site in plasma cell-free DNA (cfDNA) of COVID-19 patients, we deciphered the altered biological processes in the severe cases and demonstrated the feasibility of cfDNA in measuring the COVID-19 progression. The up- and downregulated genes in the plasma of severe patient were found to be closely related to the biological processes and functions affected by COVID-19 progression. More importantly, with the analysis of transcriptome data of blood cells and lung cells from control group and cases with severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) infection, we revealed that the upregulated genes were predominantly involved in the viral and antiviral activity in blood cells, reflecting the intense viral replication and the active reaction of immune system in the severe patients. Pathway analysis of downregulated genes in plasma DNA and lung cells also demonstrated the diminished adenosine triphosphate synthesis function in lung cells, which was evidenced to correlate with the severe COVID-19 symptoms, such as a cytokine storm and acute respiratory distress. Overall, this study revealed tissue involvement, provided insights into the mechanism of COVID-19 progression, and highlighted the utility of cfDNA as a noninvasive biomarker for disease severity inspections.
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http://dx.doi.org/10.3389/fgene.2021.663098DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8194351PMC
May 2021

Proteolysis and multimerization regulate signaling along the two-component regulatory system AdeRS.

iScience 2021 May 26;24(5):102476. Epub 2021 Apr 26.

Talent Highland and Center for Gut Microbiome Research of Med-X Institute, The First Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710061, China.

Bacterial two-component regulatory systems are ubiquitous environment-sensing signal transducers involved in pathogenesis and antibiotic resistance. The two-component regulatory system AdeRS is made up of a sensor histidine kinase AdeS and a cognate response regulator AdeR, which together reduce repression of the multidrug-resistant efflux pump AdeABC. Herein we demonstrate that an N-terminal intrinsically disordered tail in AdeR is important for the upregulation of expression, although it greatly increases the susceptibility of AdeR to proteasome-mediated degradation. We also show that AdeS assembles into a hexameric state that is necessary for its full histidine kinase activity, which appears to occur via autophosphorylation. Taken together, this study demonstrates new structural mechanisms through which two-component systems can transduce environmental signals to impact gene expression and enlightens new potential antimicrobial approach by targeting two-component regulatory systems.
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http://dx.doi.org/10.1016/j.isci.2021.102476DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8169943PMC
May 2021

Order-disorder transition of a rigid cage cation embedded in a cubic perovskite.

Nat Commun 2021 Jun 10;12(1):3548. Epub 2021 Jun 10.

School of Physical Science and Technology, ShanghaiTech University, Shanghai, China.

The structure and properties of organic-inorganic hybrid perovskites are impacted by the order-disorder transition, whose driving forces from the organic cation and the inorganic framework cannot easily be disentangled. Herein, we report the design, synthesis and properties of a cage-in-framework perovskite AthMn(N), where Ath is an organic cation 4-azatricyclo[2.2.1.0]heptanium. Ath features a rigid and spheroidal profile, such that its molecular reorientation does not alter the cubic lattice symmetry of the Mn(N) host framework. This order-disorder transition is well characterized by NMR, crystallography, and calorimetry, and associated with the realignment of Ath dipole from antiferroelectric to paraelectric. As a result, an abrupt rise in the dielectric constant was observed during the transition. Our work introduces a family of perovskite structures and provides direct insights to the order-disorder transition of hybrid materials.
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http://dx.doi.org/10.1038/s41467-021-23917-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8192939PMC
June 2021

Dynamic Changes in the Immune Response Correlate with Disease Severity and Outcomes During Infection with SARS-CoV-2.

Infect Dis Ther 2021 Jun 10. Epub 2021 Jun 10.

The First Hospital of Changsha, Changsha, Hunan, China.

Introduction: The coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has rapidly spread throughout China and worldwide. Little is known about the dynamic changes in the patient immune responses to SARS-CoV-2 and how different responses are correlated with disease severity and outcomes.

Methods: Seventy-four patients with confirmed COVID-19 were enrolled in this prospective research. The demographic information, medical history, symptoms, signs and laboratory results were analyzed and compared between severe and non-severe patients. The leukocytes, lymphocyte subsets and inflammatory cytokines were longitudinally collected.

Results: Of the 74 patients included, 17 suffered from severe disease. The severe patients tended be older (65.29 ± 12.33 years vs. 45.37 ± 18.66 years) and had a greater degree of underlying disease (41.18% vs. 24.56%), lower baseline lymphocyte counts [0.64 (0.46-0.95) × 10 vs. 1.27 (0.95-1.70) × 10], higher neutrophil-lymphocyte ratios [NLRs; 3.76 (3.15-5.51) vs. 2.07 (1.48-2.93)] and lower baseline eosinophil counts [0 (0-0.01) × 10 vs. 0.03 (0.01-0.06) × 10] than those in non-severe patients. The baseline helper T (Th) cells (335.47 vs. 666.46/μl), suppressor T(Ts) cells (158 vs. 334/μl), B cells (95 vs. 210/μl) and natural killer (NK) cells (52 vs. 122/μl) were significantly decreased in severe cases compared to that in non-severe cases. In addition, the baseline neutrophils were positively correlated with the severity of COVID-19, and the baseline lymphocytes were negatively correlated with the severity of COVID-19. The dynamic change of T cells, Th cells and IFN-γ in the severe cases were parallel to the amelioration of the disease.

Conclusions: Collectively, our study provides novel information on the kinetics of the immune responses in a cohort of COVID-19 patients with different disease severities. Furthermore, our study indicates that both innate and adaptive immune responses correlate with better clinical outcomes.
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http://dx.doi.org/10.1007/s40121-021-00458-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8190524PMC
June 2021

Nobiletin Alleviates Non-alcoholic Steatohepatitis in MCD-Induced Mice by Regulating Macrophage Polarization.

Front Physiol 2021 20;12:687744. Epub 2021 May 20.

Core Facility, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People's Hospital, Quzhou, China.

Non-alcoholic steatohepatitis (NASH) is an inflammatory disorder that is characterized by chronic activation of the hepatic inflammatory response and subsequent liver damage. The regulation of macrophage polarization in liver is closely related to the progression of NASH. The orphan nuclear receptor retinoic-acid-related orphan receptor α (RORα) and Krüppel-like factor 4 (KLF4) are key regulators which promote hepatic macrophages toward M2 phenotype and protect against NASH in mice. Nobiletin (NOB), a natural polymethoxylated flavone, is previously reported as a RORα regulator in diet-induced obese mice. However, it is still unclear whether NOB has the protective effect on NASH. In this study, we investigated the role of NOB in NASH using a methionine and choline deficient (MCD)-induced NASH mouse model. Our results showed that NOB ameliorated hepatic damage and fibrosis in MCD fed mice. NOB treatment reduced the infiltration of macrophages and neutrophils in the liver in MCD-fed mice. Of importance, NOB significantly increased the proportion of M2 macrophages and the expression of anti-inflammatory factors and . Meanwhile, NOB also decreased the population of M1 macrophages and the expression of proinflammatory cytokines. Mechanistically, NOB elevated KLF4 expression in macrophages. Inhibition of KLF4 abolished NOB regulated macrophage polarization. Furthermore, the regulation of NOB in KLF4 expression was dependent on RORα.
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http://dx.doi.org/10.3389/fphys.2021.687744DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8174844PMC
May 2021

Cardiac Involvement in Recovered Patients From COVID-19: A Preliminary 6-Month Follow-Up Study.

Front Cardiovasc Med 2021 13;8:654405. Epub 2021 May 13.

Department of Cardiology, Zhongnan Hospital of Wuhan University, Wuhan, China.

Accumulating evidence has revealed that coronavirus disease 2019 (COVID-19) patients may be complicated with myocardial injury during hospitalization. However, data regarding persistent cardiac involvement in patients who recovered from COVID-19 are limited. Our goal is to further explore the sustained impact of COVID-19 during follow-up, focusing on the cardiac involvement in the recovered patients. In this prospective observational follow-up study, we enrolled a total of 40 COVID-19 patients (20 with and 20 without cardiac injury during hospitalization) who were discharged from Zhongnan Hospital of Wuhan University for more than 6 months, and 27 patients (13 with and 14 without cardiac injury during hospitalization) were finally included in the analysis. Clinical information including self-reported symptoms, medications, laboratory findings, Short Form 36-item scores, 6-min walk test, clinical events, electrocardiogram assessment, echocardiography measurement, and cardiac magnetic resonance imaging was collected and analyzed. Among 27 patients finally included, none of patients reported any obvious cardiopulmonary symptoms at the 6-month follow-up. There were no statistically significant differences in terms of the quality of life and exercise capacity between the patients with and without cardiac injury. No significant abnormalities were detected in electrocardiogram manifestations in both groups, except for nonspecific ST-T changes, premature beats, sinus tachycardia/bradycardia, PR interval prolongation, and bundle-branch block. All patients showed normal cardiac structure and function, without any statistical differences between patients with and without cardiac injury by echocardiography. Compared with patients without cardiac injury, patients with cardiac injury exhibited a significantly higher positive proportion in late gadolinium enhancement sequences [7/13 (53.8%) vs. 1/14 (7.1%), = 0.013], accompanied by the elevation of circulating ST2 level [median (interquartile range) = 16.6 (12.1, 22.5) vs. 12.5 (9.5, 16.7); = 0.044]. Patients with cardiac injury presented higher levels of aspartate aminotransferase, creatinine, high-sensitivity troponin I, lactate dehydrogenase, and N-terminal pro-B-type natriuretic peptide than those without cardiac injury, although these indexes were within the normal range for all recovered patients at the 6-month follow-up. Among patients with cardiac injury, patients with positive late gadolinium enhancement presented higher cardiac biomarker (high-sensitivity troponin I) and inflammatory factor (high-sensitivity C-reactive protein) on admission than the late gadolinium enhancement-negative subgroup. Our preliminary 6-month follow-up study with a limited number of patients revealed persistent cardiac involvement in 29.6% (8/27) of recovered patients from COVID-19 after discharge. Patients with cardiac injury during hospitalization were more prone to develop cardiac fibrosis during their recovery. Among patients with cardiac injury, those with relatively higher cardiac biomarkers and inflammatory factors on admission appeared more likely to have cardiac involvement in the convalescence phase.
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http://dx.doi.org/10.3389/fcvm.2021.654405DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8155269PMC
May 2021

Visual detection of S with a paper-based fluorescence sensor coated with CdTe quantum dots via headspace sampling.

Luminescence 2021 May 28. Epub 2021 May 28.

Analytical & Testing Center, Sichuan University, Chengdu, Sichuan, China.

A simple method was developed in this work for facile and visual detection of S using a paper-based fluorescence (FL) sensor coated with CdTe quantum dots (QDs) by headspace sampling. With the addition of hydrochloric acid, the target S in the liquid phase would transform to H S, which was released to headspace and quenched the FL of CdTe QDs in a linear manner through a gas-solid reaction, with any possible liquid-phase interference avoided. The regular quenching caused by S in analyte solution with increased concentration could be easily observed by the naked eye, and the limit of detection (LOD) for this method was 0.13 μM and 0.93 μM for FL and visual sensing, respectively, comparable or not to that by other sensing probes. A relative standard deviation of 1.2% was accomplished from seven replicated measurements, implying the high reproducibility, and the recovery for the spiked water samples ranging from 94 to 103%, and illustrating the satisfactory reliability of this method. Moreover, the preparation of this paper sensor was facile and did not require any complicated or time-consuming procedures for additional modification or functionalization as for other probes previously reported.
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http://dx.doi.org/10.1002/bio.4097DOI Listing
May 2021

Toxicity of Water- and Organic-Soluble Wood Tar Fractions from Biomass Burning in Lung Epithelial Cells.

Chem Res Toxicol 2021 Jun 25;34(6):1588-1603. Epub 2021 May 25.

Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot 76100, Israel.

Widespread smoke from wildfires and biomass burning contributes to air pollution and the deterioration of air quality and human health. A common and major emission of biomass burning, often found in collected smoke particles, is spherical wood tar particles, also known as "tar balls". However, the toxicity of wood tar particles and the mechanisms that govern their health impacts and the impact of their complicated chemical matrix are not fully elucidated. To address these questions, we generated wood tar material from wood pyrolysis and isolated two main subfractions: water-soluble and organic-soluble fractions. The chemical characteristics as well as the cytotoxicity, oxidative damage, and DNA damage mechanisms were investigated after exposure of A549 and BEAS-2B lung epithelial cells to wood tar. Our results suggest that both wood tar subfractions reduce cell viability in exposed lung cells; however, these fractions have different modes of action that are related to their physicochemical properties. Exposure to the water-soluble wood tar fraction increased total reactive oxygen species production in the cells, decreased mitochondrial membrane potential (MMP), and induced oxidative damage and cell death, probably through apoptosis. Exposure to the organic-soluble fraction increased superoxide anion production, with a sharp decrease in MMP. DNA damage is a significant process that may explain the course of toxicity of the organic-soluble fraction. For both subfractions, exposure caused cell cycle alterations in the G2/M phase that were induced by upregulation of p21 and p16. Collectively, both subfractions of wood tar are toxic. The water-soluble fraction contains chemicals (such as phenolic compounds) that induce a strong oxidative stress response and penetrate living cells more easily. The organic-soluble fraction contained more polycyclic aromatic hydrocarbons (PAHs) and oxygenated PAHs and induced genotoxic processes, such as DNA damage.
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http://dx.doi.org/10.1021/acs.chemrestox.1c00020DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8277191PMC
June 2021

Highly Efficient Enrichment of O-GalNAc Glycopeptides by Using Immobilized Metal Ion Affinity Chromatography.

Anal Chem 2021 06 19;93(21):7579-7587. Epub 2021 May 19.

CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Science, Dalian 116023, China.

Proteomics analysis of O-GalNAc glycosylation is important for the screening of biomarkers and the assessment of therapeutic responses. However, its analysis still faces challenges due to the poor performance of currently available enrichment methods. In this study, an enrichment method was established on the basis of Ti-IMAC(IV) materials, which could enrich the intact O-GalNAc glycopeptides via both the hydrophilic interaction and affinity interaction. This method enabled nearly 200 intact O-GalNAc glycopeptides identified from only 0.1 μL of human serum. This was nearly 2-fold different from that of the HILIC method. An in-depth analysis of the O-GalNAc glycosylation was performed, and 2093 intact glycopeptides were identified from 7.2 μL of human serum samples. This is the largest O-GalNAc glycosylation database of human serum from a trace amount of sample. Furthermore, 52 significantly changed intact O-GalNAc glycopeptides were determined by the quantitative analysis of hepatocellular carcinoma (HCC) and control serum samples, indicating the potential applications of this enrichment method in biomarker discovery.
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http://dx.doi.org/10.1021/acs.analchem.0c05236DOI Listing
June 2021

Electroporation-Based Therapy for Brain Tumors: A Review.

J Biomech Eng 2021 Oct;143(10)

Energy-Based Tumor Ablation Laboratory, School of Mechatronic Engineering and Automation, Shanghai University, Shanghai 200444, China.

Electroporation-based therapy (EBT), as a high-voltage-pulse technology has been prevalent with favorable clinical outcomes in the treatment of various solid tumors. This review paper aims to promote the clinical translation of EBT for brain tumors. First, we briefly introduced the mechanism of pore formation in a cell membrane activated by external electric fields using a single cell model. Then, we summarized and discussed the current in vitro and in vivo preclinical studies, in terms of (1) the safety and effectiveness of EBT for brain tumors in animal models, and (2) the blood-brain barrier (BBB) disruption induced by EBT. Two therapeutic effects could be achieved in EBT for brain tumors simultaneously, i.e., the tumor ablation induced by irreversible electroporation (IRE) and transient BBB disruption induced by reversible electroporation (RE). The BBB disruption could potentially improve the uptake of antitumor drugs thereby enhancing brain tumor treatment. The challenges that hinder the application of EBT in the treatment of human brain tumors are discussed in the review paper as well.
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http://dx.doi.org/10.1115/1.4051184DOI Listing
October 2021

Automated Intact Glycopeptide Enrichment Method Facilitating Highly Reproducible Analysis of Serum Site-Specific N-Glycoproteome.

Anal Chem 2021 05 11;93(20):7473-7480. Epub 2021 May 11.

CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences (CAS), Dalian 116023, China.

Bottom-up proteomics has been increasingly applied in clinical research to study the disease pathophysiology and to discover disease biomarkers. However, glycoproteomic analysis always requires tedious experimental steps for intact glycopeptide enrichment, which has been the technique bottleneck for large-scale analysis of clinical samples. Herein, we developed an automated glycopeptide enrichment method for the analysis of serum site-specific N-glycoproteome. This automated method allowed for processing one sample within 20 min. It showed higher enrichment specificity, more intact glycopeptide identifications, and better quantitative reproducibility than the traditional manual method using microtip enrichment devices. We further applied this method to investigate the serum site-specific N-glycosylation changes between four patients with pancreatic cancer and seven healthy controls. The principal component analysis of intact N-glycopeptides showed good clustering across cancer and normal groups. Furthermore, we found that the site-specific glycoforms, monofucosylated and nonsialylated oligosaccharides, on IgG1 site 180 expressed a significant decrease in pancreatic cancer patients compared to healthy controls. Together, the automated method is a powerful tool for site-specific N-glycoproteomic analysis of complex biological samples, and it has great potential for clinical utilities.
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http://dx.doi.org/10.1021/acs.analchem.1c00645DOI Listing
May 2021

Removal of lead ions by two FeMn oxide substrate adsorbents.

Sci Total Environ 2021 Jun 6;773:145670. Epub 2021 Feb 6.

School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, Guangdong 510006, China.

Lead pollution has become a global concern due to its ubiquity and persistence. This study describes two FeMn oxide substrate adsorbents, namely, FeMn binary oxides (FMBO) and mesoporous FeMn binary oxide (MFMBO) covered with tannic acid film ([email protected] and [email protected]), for the treatment of Pb in water. The characterization results showed that TA was successfully coated onto the surfaces of FMBO and MFMBO. The maximum capacities of Pb on [email protected] and [email protected] were 322.08 and 357.14 mg g, respectively, which were twice those of FMBO and MFMBO. The adsorption of Pb on the adsorbents was a spontaneous, endothermic process with increasing disorder through thermodynamics studies. An overall mechanism was proposed for Pb adsorption, the improved adsorption performance of [email protected] and [email protected] is ascribed to the mesoporous characteristics and the introduction of hydroxyl groups. Further investigation indicated the adsorption of Pb could be attributed to electrostatic interactions on [email protected] and [email protected], and cation exchange existed through the formation of these internal surface complexes. The Pb-loaded adsorbents could be effectively desorbed in a dilute hydrochloric acid solution, promoting recycling and reuse of the regenerated adsorbents. These results warrant the promising application of [email protected] and [email protected] for the removal of Pb, and this work first proposed TA film-modified FMBO and MFMBO to improve its adsorption capacity in the application of environmental remediation.
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http://dx.doi.org/10.1016/j.scitotenv.2021.145670DOI Listing
June 2021

Intratracheal Poly(I:C) Exposure Accelerates the Immunological Disorder of Salivary Glands in Sjogren's-Like NOD/ShiLtJ Mice.

Front Med (Lausanne) 2021 13;8:645816. Epub 2021 Apr 13.

Department of Rheumatology and Immunology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

Evidences have suggested that Sjogren's syndrome (SS) is associated with viral infection. The aim of this study was to investigate the involvement of respiratory viral poly(I:C) in the pathogenesis of SS and potential mechanisms using a SS-like NOD/ShiLtJ (NOD) mouse model. 5-week female NOD mice were intratracheally administered poly(I:C) every other day for 5 times to mimic viral infection. Pilocarpine induced saliva secretion was determined every 8 days. Submandibular glands (SMG) and lungs were harvested for the detection of pathological changes. We found that intratracheal administration of poly(I:C) significantly advanced and enhanced the reduction of saliva flow rate in NOD mice. Furthermore, poly(I:C) treatment aggravated the histopathological lesions and inflammatory cells infiltration in SMG. Accompanied by elevated expression of IFN cytokines and IL-33, Th1 activation was enhanced in SMG of poly(I:C)-treated NOD mice, but Th17 cells activation was unchanged among the groups. In addition, intratracheal poly(I:C) exposure promoted the expression of IL-33 and increased T cells proportion in the lung, which were consistent with the change in SMG. Therefore, intratracheal poly(I:C) exposure aggravated the immunological and function disorder of SMG in NOD mice.
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http://dx.doi.org/10.3389/fmed.2021.645816DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8076562PMC
April 2021

Excitatory Effects of Calcitonin Gene-Related Peptide (CGRP) on Superficial Sp5C Neurons in Mouse Medullary Slices.

Int J Mol Sci 2021 Apr 6;22(7). Epub 2021 Apr 6.

Institute of Physiology and Pathophysiology, Friedrich-Alexander-University Erlangen-Nürnberg, 91054 Erlangen, Germany.

The neuromodulator calcitonin gene-related peptide (CGRP) is known to facilitate nociceptive transmission in the superficial laminae of the spinal trigeminal nucleus caudalis (Sp5C). The central effects of CGRP in the Sp5C are very likely to contribute to the activation of central nociceptive pathways leading to attacks of severe headaches like migraine. To examine the potential impacts of CGRP on laminae I/II neurons at cellular and synaptic levels, we performed whole-cell patch-clamp recordings in juvenile mouse brainstem slices. First, we tested the effect of CGRP on cell excitability, focusing on neurons with tonically firing action potentials upon depolarizing current injection. CGRP (100 nM) enhanced tonic discharges together with membrane depolarization, an excitatory effect that was significantly reduced when the fast synaptic transmissions were pharmacologically blocked. However, CGRP at 500 nM was capable of exciting the functionally isolated cells, in a nifedipine-sensitive manner, indicating its direct effect on membrane intrinsic properties. In voltage-clamped cells, 100 nM CGRP effectively increased the frequency of excitatory synaptic inputs, suggesting its preferential presynaptic effect. Both CGRP-induced changes in cell excitability and synaptic drives were prevented by the CGRP receptor inhibitor BIBN 4096BS. Our data provide evidence that CGRP increases neuronal activity in Sp5C superficial laminae by dose-dependently promoting excitatory synaptic drive and directly enhancing cell intrinsic properties. We propose that the combination of such pre- and postsynaptic actions of CGRP might underlie its facilitation in nociceptive transmission in situations like migraine with elevated CGRP levels.
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http://dx.doi.org/10.3390/ijms22073794DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8038766PMC
April 2021

Tonic Control of Secretory Acid Sphingomyelinase Over Ventral Hippocampal Synaptic Transmission and Neuron Excitability.

Front Cell Neurosci 2021 9;15:660561. Epub 2021 Apr 9.

Institute of Physiology and Pathophysiology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany.

The acid sphingomyelinase (ASM) converts sphingomyelin into ceramide. Recent work has advanced the ASM/ceramide system as a major player in the pathogenesis of major depressive disorder (MDD). Indeed, ASM activity is enhanced in MDD patients and antidepressant drugs like fluoxetine act as functional inhibitors of ASM. Here, we employed the specific ASM inhibitor ARC39 to explore the acute effects of the enzyme on hippocampal synaptic transmission and cell excitability in adult mouse brain slice preparations. In both field potential and whole-cell recordings, ARC39 (1-3 μM) enhanced excitatory synaptic input onto ventral hippocampal CA1 pyramidal cells. The specificity of drug action was demonstrated by its lacking effect in slices from ASM knockout mice. In control condition, ARC39 strongly reduced firing in most CA1 pyramidal cells, together with membrane hyperpolarization. Such pronounced inhibitory action of ARC39 on soma excitability was largely reversed when GABA receptors were blocked. The idea that ARC39 recruits GABAergic inhibition to dampen cell excitability was further reinforced by the drug's ability to enhance the inhibitory synaptic drive onto pyramidal cells. In pyramidal cells that were pharmacologically isolated from synaptic input, the overall effect of ARC39 on cell firing was inhibitory, but some neurons displayed a biphasic response with a transient increase in firing, suggesting that ARC39 might alter intrinsic firing properties in a cell-specific fashion. Because ARC39 is charged at physiological pH and exerted all its effects within minutes of application, we propose that the neurophysiological actions reported here are due to the inhibition of secretory rather than lysosomal ASM. In summary, the ASM inhibitor ARC39 reveals a tonic control of the enzyme over ventral hippocampal excitability, which involves the intrinsic excitability of CA1 pyramidal cells as well as their excitatory and inhibitory synaptic inputs.
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http://dx.doi.org/10.3389/fncel.2021.660561DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8062921PMC
April 2021

Continuous-flow electrosynthesis of selenium-substituted iminoisobenzofuran via oxidative cyclization of olefinic amides and diselenides.

Org Biomol Chem 2021 Apr 24;19(14):3207-3212. Epub 2021 Mar 24.

College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, 30 Puzhu Rd S., Nanjing 211816, China. and State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, 30 Puzhu Rd S., Nanjing 211816, China.

A green and efficient approach for the synthesis of selenium-substituted iminoisobenzofuran using 2-vinylbenzamides and diselenides in a continuous electrochemical microreactor has been developed. This strategy enabled the preparation of a series of iminoisobenzofuran derivatives in moderate to good yields under metal-free and oxidant-free conditions. The application of the electrochemical flow system successfully overcomes the difficulty of process control in traditional electrochemistry and achieves efficient transformation of electricity. Moreover, the continuous-flow system combined with electrosynthesis overcomes the difficulty in realizing a scale-up reaction in conventional batch-type electrolysis.
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http://dx.doi.org/10.1039/d1ob00236hDOI Listing
April 2021

HMGB1 Promotes the Release of Sonic Hedgehog From Astrocytes.

Front Immunol 2021 1;12:584097. Epub 2021 Apr 1.

Department of Immunology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

High mobility group box 1 protein (HMGB1) is known to be a trigger of inflammation in experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). However, it may play a different role in some way. Here we investigated the effect of HMGB1 on promoting sonic hedgehog (shh) release from astrocytes as well as the possible signal pathway involved in it. Firstly, shh increased in astrocytes after administration of recombinant HMGB1 or decreased after HMGB1 was blocked when stimulated by homogenate of the onset stage of EAE. Moreover, the expression of HMGB1 receptors, toll-like receptor (TLR) 2 and receptor for advanced glycation end products (RAGE) increased after HMGB1 administration in primary astrocytes. However, the enhancing effect of HMGB1 on shh release from astrocytes was suppressed only after RAGE was knocked out or blocked. Mechanistically, HMGB1 functioned by activating RAGE-mediated JNK, p38, stat3 phosphorylation. Moreover, HMGB1 could induce shh release in EAE. Additionally, intracerebroventricular injection of recombinant shh protein on the onset stage of EAE alleviated the progress of disease and decreased demylination, compared to the mice with normal saline treatment. Overall, HMGB1 promoted the release of shh from astrocytes through signal pathway JNK, p38 and stat3 mediated by receptor RAGE, which may provide new insights of HMGB1 function in EAE.
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http://dx.doi.org/10.3389/fimmu.2021.584097DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8047406PMC
June 2021

Structural characterization and evaluation the elicitors activity of polysaccharides from Chrysanthemum indicum.

Carbohydr Polym 2021 Jul 27;263:117994. Epub 2021 Mar 27.

Department of Forestry and Biotechnology, Zhejiang Provincial Key Laboratory of Resources Protection and Innovation of Traditional Chinese Medicine, Zhejiang A&F University, Hangzhou 311300, PR China. Electronic address:

This research evaluates the elicitors activity and structure characterization of four Chrysanthemum indicum polysaccharides (CIPs) which were isolated from C. indicum, obtained CIP1, CIP2, CIP3, CIP4. Results demonstrated that there was a distinct difference in inducibility and CIP3 was significantly stronger than other CIPs through bioactivity-tests. Taking CIP3 with total carbohydrate content 91.93 % as a representative, its structure was elucidated as a relative molecular weight of 8. 741 × 10 g/mol and mainly composed of xylose, galacturonic acid, galactose and glucuronic acid. Through GC, IR and NMR, CIP3 was determined to possess a backbone comprised of T-α-d-GalpA, 1,4-α-d-GlcpA, 1,2-α-d-Xylp, 1,3-α-l-Rhap, 1,2,4-α-l-Rhap and sidechains comprised of 1,3-β-d-Galp, 1,6-α-d-Galp, T-α-Glcp, 1,3-β-d-Glcp, 1,4-α-d-Glcp, 1,3,4-α-d-Manp, T-α-l-Fucp. Further results indicated that CIP3 with active sidechains could significantly increase the expression of defense genes in Atractylodes macrocephala Koidz (AM). It is believed that the sidechains of CIP3 were necessary to its elicitor activity via bioactivity tests.
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http://dx.doi.org/10.1016/j.carbpol.2021.117994DOI Listing
July 2021

An study of a custom-made high-frequency irreversible electroporation generator on different tissues for clinically relevant ablation zones.

Int J Hyperthermia 2021 ;38(1):593-603

Division of Biomedical Engineering, University of Saskatchewan, Saskatoon, Canada.

Purpose: To examine the ablation zone, muscle contractions, and temperature increases in both rabbit liver and kidney models for a custom-made high-frequency irreversible electroporation (H-FIRE) generator.

Materials And Methods: A total of 18 New Zealand white rabbits were used to investigate five H-FIRE protocols ( = 3 for each protocol) and an IRE protocol ( = 3) for the performance of the designed H-FIRE device in both liver and kidney tissues. The ablation zone was determined by using histological analysis 72 h after treatment. The extent of muscle contractions and temperature change during the application of pulse energy were measured by a commercial accelerometer attached to animals and fiber optic temperature probe inserted into organs with IRE electrodes, respectively.

Results: All H-FIRE protocols were able to generate visible ablation zones without muscle contractions, for both liver and kidney tissues. The area of ablation zone generated in H-FIRE pulse protocols (e.g., 0.3-1 μs, 2000 V, and 90-195 bursts) appears similar to that of IRE protocol (100 μs, 1000 V, and 90 pulses) in both liver and kidney tissues. No significant temperature increase was noticed except for the protocol with the highest pulse energy (e.g., 1 μs, 2000 V, and 180 bursts).

Conclusion: Our work serves to complement the current H-FIRE pulse waveforms, which can be optimized to significantly improve the quality of ablation zone in terms of precision for liver and kidney tumors in clinical setting.
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http://dx.doi.org/10.1080/02656736.2021.1912417DOI Listing
July 2021

Microvascular comparison in younger and older patients with retinal vein occlusion analyzed by OCT angiography.

BMC Ophthalmol 2021 Apr 5;21(1):161. Epub 2021 Apr 5.

Eye Center, Second Affiliated Hospital, School of Medicine, Zhejiang University, No.88, Jiefang Road, 310009, Hangzhou, China.

Background: To compare changes in retinal microvasculature of young and elderly patients with retinal vein occlusion (RVO) after anti-VEGF treatment.

Methods: RVO patients who underwent anti-VEGF treatment were retrospectively reviewed and categorized into two groups based on age. The OCT angiography images were obtained during each visit. Best corrected visual acuity (BCVA), vessel density (VD) and foveal avascular zone (FAZ) were measured and compared between the two groups. Vision improvements and retinal microvasculature changes were also correlated.

Results: Twenty patients with 20 eyes were enrolled in the younger group and 46 patients with 46 eyes were enrolled in the older group. Younger patients demonstrated better BCVA, higher VD and smaller FAZ than older patients at 12 months after the first anti-VEGF treatment. The improvement of VD was observed only in the younger group. A positive correlation between vision improvement and VD increase was noted.

Conclusions: Young patients with RVO can achieve rapid rehabilitation of deep retinal vasculature which lead to a better visual outcome.
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http://dx.doi.org/10.1186/s12886-021-01931-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8022394PMC
April 2021

Allograft or Recipient ST2 Deficiency Oppositely Affected Cardiac Allograft Vasculopathy Differentially Altering Immune Cells Infiltration.

Front Immunol 2021 18;12:657803. Epub 2021 Mar 18.

Department of Immunology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

The role of IL-33/ST2 signaling in cardiac allograft vasculopathy (CAV) is not fully addressed. Here, we investigated the role of IL-33/ST2 signaling in allograft or recipient in CAV respectively using MHC-mismatch murine chronic cardiac allograft rejection model. We found that recipients ST2 deficiency significantly exacerbated allograft vascular occlusion and fibrosis, accompanied by increased F4/80 macrophages and CD3 T cells infiltration in allografts. In contrast, allografts ST2 deficiency resulted in decreased infiltration of F4/80 macrophages, CD3 T cells and CD20 B cells and thus alleviated vascular occlusion and fibrosis of allografts. These findings indicated that allografts or recipients ST2 deficiency oppositely affected cardiac allograft vasculopathy/fibrosis differentially altering immune cells infiltration, which suggest that interrupting IL-33/ST2 signaling locally or systematically after heart transplantation leads different outcome.
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http://dx.doi.org/10.3389/fimmu.2021.657803DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8012811PMC
March 2021

The complete mitochondrial genome of (Hemiptera: Aphididae).

Mitochondrial DNA B Resour 2021 Mar 18;6(3):974-975. Epub 2021 Mar 18.

School of Life Sciences, Guizhou Normal University, Gui'an, Guizhou, China.

The mitochondrial genome of (Hemiptera: Aphididae) was determined by Illumina paired-end sequencing. The genome size is 15,927 bp with 45.19% A, 39.03% T, 9.92% C and 5.86% G. It is encoded with 13 protein-coding genes, 22 transfer RNAs and two ribosome RNAs. The phylogenetic tree showed that . clustered within clade of Aphididae, had a closer relationship with genus than the rest genera. This study provides important information for future study on the evolution, genetic and molecular biology of .
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http://dx.doi.org/10.1080/23802359.2021.1888334DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7995914PMC
March 2021

[Effect of extract of Quzhou Aurantii Fructus on hepatic inflammation and NF-κB/NLRP3 inflammasome pathway in CCl_4-induced liver fibrosis mice].

Zhongguo Zhong Yao Za Zhi 2021 Mar;46(6):1474-1479

Quzhou People's Hospital Quzhou 324000,China.

To study the effect and mechanism of extract of Quzhou Aurantii Fructus(QAF) on liver inflammation in CCl_4-induced liver fibrosis mice. Totally 60 C57 BL/6 male mice were randomly divided into control group(distilled water, oral), model group(distilled water, oral), colchicines group(Col, colchicines 2 mg·kg~(-1)·d~(-1), oral), low-dose QAF group(QAF-L, QAF 100 mg·kg~(-1)·d~(-1), oral) and high-dose QAF group(QAF-H, QAF 300 mg·kg~(-1)·d~(-1), oral) by random number table method. The model group and each administration group were injected with carbon tetrachloride(CCl_4) 1 mL·kg~(-1)(CCl_4-olive oil 1∶4), twice a week, totally 6 weeks. After the last administration, the mice were sacrificed, and serum and liver tissue were collected. Serum ALT and AST levels were measured in each group to observe the liver function of mice. The pathological changes and inflammatory cell infiltration in liver were observed by HE staining and F4/80 immunohistochemical staining. The mRNA expressions of TNF-α, IL-18 and IL-1β were detected by RT-PCR. The protein expressions of IκBα, p-IKKα/β, p-p65, NLRP3, caspase-1 and cleaved caspase-1 were analyzed by Western blot. The results showed that QAF significantly reduced serum ALT and AST levels, and alleviated the degree of liver damage.The results of immunohistochemistry showed that QAF significantly reduced liver inflammatory cell infiltration in liver fibrosis mice. The results of RT-PCR and Western blot showed that QAF significantly inhibited mRNA expressions of TNF-α, IL-18 and IL-1β in liver of fibrosis mice. QAF also suppressed the degradation of IκBα protein and reduced p-IKKα/β, p-p65, NLRP3 and cleaved caspase-1 protein expressions. In conclusion, QAF improves CCl_4-induced liver fibrosis in mice. The mechanism may be related to the inhibition of NF-κB/NLRP3 inflammasome-mediated inflammation signaling pathway.
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http://dx.doi.org/10.19540/j.cnki.cjcmm.20201201.401DOI Listing
March 2021

Extracellular HMGB1 Contributes to the Chronic Cardiac Allograft Vasculopathy/Fibrosis by Modulating TGF-β1 Signaling.

Front Immunol 2021 10;12:641973. Epub 2021 Mar 10.

Department of Immunology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

Cardiac allograft vasculopathy (CAV) charactered with aberrant remodeling and fibrosis usually leads to the loss of graft after heart transplantation. Our previous work has reported that extracellular high-mobility group box 1 (HMGB1) participated in the CAV progression via promoting inflammatory cells infiltration and immune damage. The aim of this study was to investigate the involvement of HMGB1 in the pathogenesis of CAV/fibrosis and potential mechanisms using a chronic cardiac rejection model in mice. We found high levels of transforming growth factor (TGF)-β1 in cardiac allografts after transplantation. Treatment with HMGB1 neutralizing antibody markedly prolonged the allograft survival accompanied by attenuated fibrosis of cardiac allograft, decreased fibroblasts-to-myofibroblasts conversion, and reduced synthesis and release of TGF-β1. In addition, recombinant HMGB1 stimulation promoted release of active TGF-β1 from cardiac fibroblasts and macrophages , and subsequent phosphorylation of Smad2 and Smad3 which were downstream of TGF-β1 signaling. These data indicate that HMGB1 contributes to the CAV/fibrosis via promoting the activation of TGF-β1/Smad signaling. Targeting HMGB1 might become a new therapeutic strategy for inhibiting cardiac allograft fibrosis and dysfunction.
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http://dx.doi.org/10.3389/fimmu.2021.641973DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7988222PMC
March 2021

The transcription regulator ACTR controls ACT-toxin biosynthesis and pathogenicity in the tangerine pathotype of Alternaria alternata.

Microbiol Res 2021 Jul 16;248:126747. Epub 2021 Mar 16.

Key Lab of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China. Electronic address:

The host-selective ACT toxin is essential for the pathogenesis of the citrus fungal pathogen Alternaria alternata. However, the mechanism of ACT-toxin gene clusters ACT-toxin biosynthesis regulated by is still poorly understood. The biosynthesis of ACT toxin is mainly regulated by multiple ACT toxin genes located in the secondary metabolite gene cluster. In this study, we reported a transcription regulator ACTR contributes ACT toxin biosynthesis through mediating ACT toxin synthesis gene ACTS4 in Alternaria alternata. We generated ACTR-disrupted and -silenced mutants in the tangerine pathotype of A. alternata. Phenotype analysis showed that the ACTR mutants displayed a significant loss of ACT toxin production and a decreased virulence on citrus leaves whereas the vegetative growth and sporulation were not affected, indicating an essential role of ACTR in both ACT toxin biosynthesis and pathogenicity. To elucidate the transcription network of ACTR, we performed RNA-Seq experiments on wild-type and ACTR null mutant and identified genes that were differentially expressed between two genotypes. Transcriptome profiling and RT-qPCR analysis demonstrated that the ACT toxin biosynthetic gene ACTS4 is down-regulated in ACTR mutant. We generated ACTS4 knock-down mutant and found that the pathogenicity of ACTS4 mutant was severely impaired. Interestingly, both ACTR and ACTS4 are not involved in the response to different abiotic stresses including oxidative stress, salt stress, cell-wall disrupting regents, and metal ion stress, indicating the function of these two genes is highly specific. In conclusion, our results highlight the important regulatory role of ACTR in ACT toxin biosynthesis through mediating ACT toxin synthesis gene ACTS4 and underline the essential role of in the tangerine pathotype of A. alternata.
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http://dx.doi.org/10.1016/j.micres.2021.126747DOI Listing
July 2021