Publications by authors named "Jing Kang"

340 Publications

Corrigendum: The Dental Team: An Additional Resource for Delivering Vaccinations.

Front Med (Lausanne) 2021 25;8:653861. Epub 2021 Mar 25.

School of Dentistry, University of Leeds, Leeds, United Kingdom.

[This corrects the article DOI: 10.3389/fmed.2020.606242.].
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http://dx.doi.org/10.3389/fmed.2021.653861DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8028012PMC
March 2021

Adsorption property and mechanism of polyacrylate-divinylbenzene microspheres for removal of trace organic micropollutants from water.

Sci Total Environ 2021 Mar 20;781:146635. Epub 2021 Mar 20.

State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China. Electronic address:

In this study, polyacrylate-divinylbenzene (PADVB) microspheres were facilely prepared via the precipitation polymerization method, and the microspheres were used as an efficient adsorbent for the removal of trace level organic micropollutants (OMPs) from environmental waters. Preparation conditions of PADVB microspheres were optimized, and the characterizations of the microspheres were performed using a scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), and N adsorption/desorption isotherms. The microspheres had broad-spectrum adsorption ability for various organic micropollutants containing hydroxy, amidogen, aromatic or heteroaromatic ring in their chemical structure, such as atrazine, 2,4 dichlorophenol, 2,4 dibromophenol, 2,6 dichlorophenol, sulfamethoxazole, estradiol, and bisphenol A. Besides, the effects of initial concentration, initial pH value, adsorption time, and the type of adsorbates on the adsorption performance were investigated systematically. PADVB microspheres could be used for removing trace OMPs from environmental water. Monolayer and homogeneous sorption process occurred on the surface of PADVB microspheres through chemisorption mechanisms. The X-ray photoelectron spectroscopy (XPS) and FT-IR spectrum of PADVB microspheres before and after adsorption proved that the OMPs adsorption onto PADVB microspheres was mainly due to the formation of the hydrogen bond and π-π electron-donor-acceptor (EDA) interactions. Besides, PADVB microspheres can be recovered for reuse via (low-pressure) microfiltration and could be regenerated sufficiently by using 80% (v/v) ethanol.
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http://dx.doi.org/10.1016/j.scitotenv.2021.146635DOI Listing
March 2021

Membrane Nanoparticles Derived from ACE2-Rich Cells Block SARS-CoV-2 Infection.

ACS Nano 2021 Mar 18. Epub 2021 Mar 18.

Department of Nephrology, The Key Laboratory for The Prevention and Treatment of Chronic Kidney Disease of Chongqing, Xinqiao Hospital, Third Military Medical University, Chongqing, 400037, China.

The ongoing COVID-19 pandemic worldwide necessitates the development of therapeutics against SARS-CoV-2. ACE2 is the main receptor of SARS-CoV-2 S1 and mediates viral entry into host cells. Herein, membrane nanoparticles (NPs) prepared from ACE2-rich cells were discovered to have potent capacity to block SARS-CoV-2 infection. The membranes of human embryonic kidney-239T cells highly expressing ACE2 were applied to prepare NPs using an extrusion method. The nanomaterials, termed ACE2-NPs, contained 265.1 ng mg ACE2 on the surface and acted as baits to trap S1 in a dose-dependent manner, resulting in reduced recruitment of the viral ligand to HK-2 human renal tubular epithelial cells. Aside from affecting receptor recongnition, S1 translocated to the cytoplasm and induced apoptosis by reducing optic atrophy 1 expression and increasing cytochrome c release, which was also inhibited by ACE2-NPs. Further investigations revealed that ACE2-NPs efficiently suppressed SARS-CoV-2 S pseudovirions entry into host cells and blocked viral infection and . This study characterizes easy-to-produce memrbane nanoantagonists of SARS-CoV-2 that enrich the existing antiviral arsenal and provide possibilities for COVID-19 treatment.
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http://dx.doi.org/10.1021/acsnano.0c06836DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8009101PMC
March 2021

Experimental study on renoprotective effect of intermedin on diabetic nephropathy.

Mol Cell Endocrinol 2021 Mar 4;528:111224. Epub 2021 Mar 4.

Department of Nephrology, Postdoctoral Workstation of Shanxi Provincial People's Hospital, The Affiliated People's Hospital of Shanxi Medical University, Shanxi Kidney Disease Institute, Taiyuan, Shanxi, 030012, China. Electronic address:

Intermedin(IMD) is a novel member of the calcitonin/calcitonin gene-related peptide (CT/CGRP) family that has anti-inflammatory, antioxidant and anti-apoptosis properties. This study aimed to evaluate the renoprotective effects of IMD on podocyte apoptotic loss and slit diaphragm protein deficiency the kidneys of rats with in streptozotocin (STZ) induced diabetes in high glucose-exposed podocytes. Our results showed that IMD significantly attenuated proteinuria, and alleviated the abnormal alterations in glomerular ultrastructure in vivo. IMD also improved the induction of slit diaphragm proteins, and restored the decreased Bcl-2 expression and suppressed Bax and caspase-3 induction in the diabetic glomeruli. In addition, IMD attenuated podocyte apoptosis and filamentous actin (F-actin) rearrangement in high glucose-exposed podocytes. Exposure to high glucose elevated the unfolded protein response (UPR) to endoplasmic reticulum (ER) stress in renal podocytes, and IMD treatment blocked such ER stress responses pertinent to podocyte apoptosis and reduced synthesis of slit diaphragm proteins in vivo and in vitro. These observations demonstrate that targeting ER stress is an underlying mechanism of IMD-mediated amelioration of diabetes-associated podocyte injury and dysfunction.
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http://dx.doi.org/10.1016/j.mce.2021.111224DOI Listing
March 2021

Runge-Kutta Numerical Method Followed by Richardson's Extrapolation for Efficient Ion Rejection Reassessment of a Novel Defect-Free Synthesized Nanofiltration Membrane.

Membranes (Basel) 2021 Feb 14;11(2). Epub 2021 Feb 14.

State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China.

A defect-free, loose, and strong layer consisting of zirconium (Zr) nanoparticles (NPs) has been successfully established on a polyacrylonitrile (PAN) ultrafiltration substrate by an in-situ formation process. The resulting organic-inorganic nanofiltration (NF) membrane, NF-PANZr, has been accurately characterized not only with regard to its properties but also its structure by the atomic force microscopy, field emission scanning electron microscopy, and energy dispersive spectroscopy. A sophisticated computing model consisting of the Runge-Kutta method followed by Richardson extrapolation was applied in this investigation to solve the extended Nernst-Planck equations, which govern the solute particles' transport across the active layer of NF-PANZr. A smart, adaptive step-size routine is chosen for this simple and robust method, also known as RK4 (fourth-order Runge-Kutta). The NF-PANZr membrane was less performant toward monovalent ions, and its rejection rate for multivalent ions reached 99.3%. The water flux of the NF-PANZr membrane was as high as 58 L · m · h. Richardson's extrapolation was then used to get a better approximation of Cl and Mg rejection, the relative errors were, respectively, 0.09% and 0.01% for Cl and Mg. While waiting for the rise and expansion of machine learning in the prediction of rejection performance, we strongly recommend the development of better NF models and further validation of existing ones.
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http://dx.doi.org/10.3390/membranes11020130DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7918593PMC
February 2021

EEM-PARAFAC characterization of dissolved organic matter and its relationship with disinfection by-products formation potential in drinking water sources of northeastern China.

Sci Total Environ 2021 Feb 2;774:145297. Epub 2021 Feb 2.

State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China. Electronic address:

Dissolved organic matter (DOM) is the precursor of disinfection by-products (DBPs) which is widely found in the aquatic environment. The analysis of DOM in raw water is helpful to evaluate the formation potentials of DBPs. However, there is relatively little research on the DOM identification of raw water in northern China. In this study, the variation in DOM in M reservoir water in one year by fluorescence excitation-emission matrix-parallel factor analysis (EEM-PARAFAC) was investigated to evaluate the DBP formation potential (DBPFP). The results suggested that five components, namely, two humic-like substances (C2, C3), two fulvic-like substances (C1, C4) and one protein-like substance (C5), were identified in the DOM of M reservoir water. The content of DOM in autumn and winter was higher than that in spring and summer. The source of DOM in the water body of M reservoir was mainly from terrestrial source, but less from aquatic source. The source, types and humification degree of DOM affect the formation of DBPs. The formation potential of DBPs had the following order: trihalomethanes (THMs) > dichloroacetic acid (TCAA) > trichloroacetic acid (DCAA) > chloral hydrate (CH). The formation potentials of THM and TCAA were strongly correlated with C2 (r = 0.805, r = 0.857). The formation potential of CH has a good correlation with C1 (r = 0.722). The formation of DCAA has a good correlation with C4 (r = 0.787). DOM and DBPFP were negatively correlated with the biological index (BIX) and fluorescence index (FI) of the raw water, and positively correlated with the humification index (HIX).
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http://dx.doi.org/10.1016/j.scitotenv.2021.145297DOI Listing
February 2021

Dual stimuli-responsive nanoplatform based on core-shell structured graphene oxide/mesoporous silica@alginate.

Int J Biol Macromol 2021 Apr 4;175:209-216. Epub 2021 Feb 4.

Jiangsu Key Laboratory of Advanced Materials and Technology, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China. Electronic address:

A dual stimuli-responsive nanoplatform was rationally designed for controlled drug delivery. The nanosheets of graphene oxide (GO) were first modified with aminated mesoporous silica (NH-mSiO), and then methotrexate (MTX) was loaded into the mesopores of mSiO. Alginate (Alg) acted as the "gatekeeper" was then anchored to the MTX-loaded GO/NH-mSiO by amidation reaction, achieving the encapsulation of MTX in the core-shell structured GO/mSiO@Alg. Due to the high pH sensitivity of amide bond and the excellent photothermal conversion ability of GO, the constructed nanoplatform could be used for pH and near-infrared (NIR) controlled delivery of MTX. The results of cell viability test demonstrate the high inhibitory rate of the dual stimuli-responsive nanoplatform toward hepatoma (HepG2) cells.
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http://dx.doi.org/10.1016/j.ijbiomac.2021.02.021DOI Listing
April 2021

Caenorhabditis elegans homologue of Fam210 is required for oogenesis and reproduction.

J Genet Genomics 2020 11 5;47(11):694-704. Epub 2020 Dec 5.

MOE Key Laboratory of Biosystems Homeostasis and Protection, College of Life Sciences, Zhejiang University, Hangzhou 310058, China. Electronic address:

Mitochondria are the central hub for many metabolic processes, including the citric acid cycle, oxidative phosphorylation, and fatty acid oxidation. Recent studies have identified a new mitochondrial protein family, Fam210, that regulates bone metabolism and red cell development in vertebrates. The model organism Caenorhabditis elegans has a Fam210 gene, y56a3a.22, but it lacks both bones and red blood cells. In this study, we report that Y56A3A.22 plays a crucial role in regulating mitochondrial protein homeostasis and reproduction. The nematode y56a3a.22 is expressed in various tissues, including the intestine, muscle, hypodermis, and germline, and its encoded protein is predominantly localized in mitochondria. y56a3a.22 deletion mutants are sterile owing to impaired oogenesis. Loss of Y56A3A.22 induced mitochondrial unfolded protein response (UPR), which is mediated through the ATFS-1-dependent pathway, in tissues such as the intestine, germline, hypodermis, and vulval muscle. We further show that infertility and UPR induces by Y56A3A.22 deficiency are not attributed to systemic iron deficiency. Together, our study reveals an important role of Y56A3A.22 in regulating mitochondrial protein homeostasis and oogenesis and provides a new genetic tool for exploring the mechanisms regulating mitochondrial metabolism and reproduction as well as the fundamental role of the Fam210 family.
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http://dx.doi.org/10.1016/j.jgg.2020.10.008DOI Listing
November 2020

Improvement of the fabricated and application of aluminosilicate-based microfiltration membrane.

Chemosphere 2021 Jan 16;273:129628. Epub 2021 Jan 16.

State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China. Electronic address:

Aluminosilicate composite materials are characterized by their low cost, nontoxicity and facilely shaped. Membrane prepared using aluminosilicate composites have the following disadvantages: large mean pore size and low mechanical strength. To address these limitations, flat microfiltration membranes were fabricated using SiO powder and aluminosilicate composite as raw materials. The membrane performance was optimized by regulating the particle size of SiO, the ratio of SiO to aluminosilicate composite (s/a), and the type of chemical admixture. The X-ray diffraction results indicated that the crystalline SiO particles were favorable for the preparation of membranes with higher bending strengths. The decreasing particle sizes of SiO (1.33-0.15 μm) decreased the pore size distribution. The bending strength of the membrane reduced with an increase in s/a, while was effectively enhanced by adding dissolved NaSiO. The optimized inorganic microfiltration membrane could also catalyze ozone to remove 100% of benzophenone-4 with an initial concentration of 10 mg L within 15 min, and TOC removal by 52.67%. This paper presents a revised method for preparing an inorganic microfiltration membrane, which is an increasingly promising material for water treatment because of its low cost, low energy consumption, and high catalytic performance.
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http://dx.doi.org/10.1016/j.chemosphere.2021.129628DOI Listing
January 2021

Docosahexanoic acid signals through the Nrf2-Nqo1 pathway to maintain redox balance and promote neurite outgrowth.

Mol Biol Cell 2021 04 27;32(7):511-520. Epub 2021 Jan 27.

Department of Molecular and Cellular Biology, The University of Guelph, Guelph, ON N1G 2W1, Canada.

Evidence suggests that n-3 polyunsaturated fatty acids may act as activators of the Nrf2 antioxidant pathway. The antioxidant response, in turn, promotes neuronal differentiation and neurite outgrowth. Nrf2 has recently been suggested to be a cell intrinsic mediator of docosohexanoic acid (DHA) signaling. In the current study, we assessed whether DHA-mediated axodendritic development was dependent on activation of the Nrf2 pathway and whether Nrf2 protected from agrochemical-induced neuritic retraction. Expression profiling of the DHA-enriched mouse brain relative to wild type showed a significant enrichment of genes associated with neuronal development and neuronal projection and genes associated with the Nrf2-transcriptional pathway. Moreover, we found that primary cortical neurons treated with DHA showed a dose-dependent increase in Nrf2 transcriptional activity and Nrf2-target gene expression. DHA-mediated activation of Nrf2 promoted neurite outgrowth and inhibited oxidative stress-induced neuritic retraction evoked by exposure to agrochemicals. Finally, we provide evidence that this effect is largely dependent on induction of the Nrf2-target gene NAD(P)H: (quinone acceptor) oxidoreductase 1 (NQO1), and that silencing of either or blocks the effects of DHA on the axodendritic compartment. Collectively, these data support a role for the Nrf2-NQO1 pathway in DHA-mediated axodendritic development and protection from agrochemical exposure.
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http://dx.doi.org/10.1091/mbc.E20-09-0599DOI Listing
April 2021

Beneficial effects of an endogenous enrichment in n3-PUFAs on Wnt signaling are associated with attenuation of alcohol-mediated liver disease in mice.

FASEB J 2021 Feb;35(2):e21377

Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, University of Louisville, Louisville, KY, USA.

Alcohol-associated liver disease (ALD) is a major human health issue for which there are limited treatment options. Experimental evidence suggests that nutrition plays an important role in ALD pathogenesis, and specific dietary fatty acids, for example, n6 or n3-PUFAs, may exacerbate or attenuate ALD, respectively. The purpose of the current study was to determine whether the beneficial effects of n3-PUFA enrichment in ALD were mediated, in part, by improvement in Wnt signaling. Wild-type (WT) and fat-1 transgenic mice (that endogenously convert n6-PUFAs to n3) were fed ethanol (EtOH) for 6 weeks followed by a single LPS challenge. fat-1 mice had less severe liver damage than WT littermates as evidenced by reduced plasma alanine aminotransferase, hepatic steatosis, liver tissue neutrophil infiltration, and pro-inflammatory cytokine expression. WT mice had a greater downregulation of Axin2, a key gene in the Wnt pathway, than fat-1 mice in response to EtOH and LPS. Further, there were significant differences between WT and fat-1 EtOH+LPS-challenged mice in the expression of five additional genes linked to the Wnt signaling pathway, including Apc, Fosl1/Fra-1, Mapk8/Jnk-1, Porcn, and Nkd1. Compared to WT, primary hepatocytes isolated from fat-1 mice exhibited more effective Wnt signaling and were more resistant to EtOH-, palmitic acid-, or TNFα-induced cell death. Further, we demonstrated that the n3-PUFA-derived lipid mediators, resolvins D1 and E1, can regulate hepatocyte expression of several Wnt-related genes that were differentially expressed between WT and fat-1 mice. These data demonstrate a novel mechanism by which n3-PUFAs can ameliorate ALD.
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http://dx.doi.org/10.1096/fj.202001202RDOI Listing
February 2021

NINJ1 mediates plasma membrane rupture during lytic cell death.

Nature 2021 Mar 20;591(7848):131-136. Epub 2021 Jan 20.

Department of Physiological Chemistry, Genentech Inc., South San Francisco, CA, USA.

Plasma membrane rupture (PMR) is the final cataclysmic event in lytic cell death. PMR releases intracellular molecules known as damage-associated molecular patterns (DAMPs) that propagate the inflammatory response. The underlying mechanism of PMR, however, is unknown. Here we show that the cell-surface NINJ1 protein, which contains two transmembrane regions, has an essential role in the induction of PMR. A forward-genetic screen of randomly mutagenized mice linked NINJ1 to PMR. Ninj1 macrophages exhibited impaired PMR in response to diverse inducers of pyroptotic, necrotic and apoptotic cell death, and were unable to release numerous intracellular proteins including HMGB1 (a known DAMP) and LDH (a standard measure of PMR). Ninj1 macrophages died, but with a distinctive and persistent ballooned morphology, attributable to defective disintegration of bubble-like herniations. Ninj1 mice were more susceptible than wild-type mice to infection with Citrobacter rodentium, which suggests a role for PMR in anti-bacterial host defence. Mechanistically, NINJ1 used an evolutionarily conserved extracellular domain for oligomerization and subsequent PMR. The discovery of NINJ1 as a mediator of PMR overturns the long-held idea that cell death-related PMR is a passive event.
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http://dx.doi.org/10.1038/s41586-021-03218-7DOI Listing
March 2021

Outer membrane vesicles containing OmpA induce mitochondrial fragmentation to promote pathogenesis of Acinetobacter baumannii.

Sci Rep 2021 Jan 12;11(1):618. Epub 2021 Jan 12.

Department of Infectious Diseases, Genentech Inc., 1 DNA Way, South San Francisco, CA, 94080, USA.

Acinetobacter baumannii is a highly antibiotic resistant Gram-negative bacterium that causes life-threatening infections in humans with a very high mortality rate. A. baumannii is an extracellular pathogen with poorly understood virulence mechanisms. Here we report that A. baumannii employs the release of outer membrane vesicles (OMVs) containing the outer membrane protein A (OmpA) to promote bacterial pathogenesis and dissemination. OMVs containing OmpA are taken up by mammalian cells where they activate the host GTPase dynamin-related protein 1 (DRP1). OmpA mediated activation of DRP1 enhances its accumulation on mitochondria that causes mitochondrial fragmentation, elevation in reactive oxygen species (ROS) production and cell death. Loss of DRP1 rescues these phenotypes. Our data show that OmpA is sufficient to induce mitochondrial fragmentation and cytotoxicity since its expression in E. coli transfers its pathogenic properties to E. coli. A. baumannii infection in mice also induces mitochondrial damage in alveolar macrophages in an OmpA dependent manner. We finally show that OmpA is also required for systemic dissemination in the mouse lung infection model. In this study we uncover the mechanism of OmpA as a virulence factor in A. baumannii infections and further establish the host cell factor required for its pathogenic effects.
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http://dx.doi.org/10.1038/s41598-020-79966-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7804284PMC
January 2021

Effect of remote management on comprehensive management of diabetes mellitus during the COVID-19 epidemic.

Prim Care Diabetes 2021 Jan 1. Epub 2021 Jan 1.

Department of Endocrinology, The Second Hospital of Jilin University, Changchun, 130041 Jilin, PR China. Electronic address:

Objective: We learned about the health condition of people with diabetes during the COVID-19 epidemic through a questionnaire survey. We conducted a randomized controlled study to confirm the effectiveness of remote management using the mobile phone WeChat app on comprehensive management of diabetes mellitus during the COVID-19 epidemic.

Methods: We distributed questionnaires that collected information on the health condition of people with diabetes during the COVID-19 epidemic through the WeChat app. We assigned 90 cases to the intervention group and 90 cases to the control group. The intervention group was managed remotely through the WeChat app, and the control group received traditional medical treatment. The blood glucose, blood pressure, body mass index (BMI), time in range (TIR) and incidence of hypoglycemia were compared after three months of follow-up.

Results: The BMI and postprandial blood glucose (PBG) of the control group at 3 months was significantly higher than that at baseline (P < 0.001), and TIR decreased at 3 months (P < 0.05). There was no significant difference in blood pressure compared with baseline in the control group, while blood pressure decreased in the intervention group (P < 0.05). In the intervention group, fast blood glucose(FBG) and PBG decreased compared with their baseline values, and the TIR level increased, both of which were statistically significant (P < 0.001). The FBG, PBG, and TIR of the intervention group were better than those in the control group at 3 months (P < 0.05). There was no difference in the incidence of hypoglycemia between the two groups.

Conclusion: During the COVID-19 epidemic, diabetes treatment has been facing new challenges, and the traditional treatment mode is limited. Remote management can increase TIR without increasing the risk of hypoglycemia. Remote management can prevent weight gain and improve patients' self-management and compliance during the COVID-19 epidemic.
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http://dx.doi.org/10.1016/j.pcd.2020.12.004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7836521PMC
January 2021

The performance of aerobic granular sludge for simulated swine wastewater treatment and the removal mechanism of tetracycline.

J Hazard Mater 2021 Apr 15;408:124762. Epub 2020 Dec 15.

State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China.

In this study, aerobic granular sludge (AGS) cultivated in a sequencing batch reactor (SBR) was employed to investigate its ability on the decontamination of tetracycline (TC) from swine wastewater (SWW). The removal mechanism of TC by AGS was studied. Results showed that the AGS process could effectively remove chemical oxygen demand (COD), ammonium nitrogen (NH-N), total phosphorus (TP), and TC during operation. The removal of TC by AGS was mainly due to adsorption and biodegradation, and the contribution rate of biodegradation increased after AGS adaptation to TC. Twenty-two by-products were detected during biodegradation of TC, and accordingly the degradation pathway of TC was speculated. Compared to the control reactor, the microbe diversity in different levels of classification was richer in the TC fed reactor according to the LefSe analysis. The results revealed that enzymes that participated in the metabolic pathway of microbial biodegradation of polycyclic aromatic compounds were enriched and may have played a key role in the biodegradation of TC.
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http://dx.doi.org/10.1016/j.jhazmat.2020.124762DOI Listing
April 2021

Selective adsorption and enhanced photodegradation of diclofenac in water by molecularly imprinted TiO.

J Hazard Mater 2021 Apr 10;407:124759. Epub 2020 Dec 10.

State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China. Electronic address:

In the paper, molecularly imprinted TiO was prepared by surface molecularly imprinted technology and liquid phase deposition method for preferential removal of persistent toxic pollutants from complex environmental water. Diclofenac was selected as the template molecule and target for photodegradation study. The characterization results of SEM, TEM, FTIR and XRD showed that the TiO film with imprinted diclofenac was successfully synthesized on the surface of TiO particles. Meanwhile, the adsorption and photodegradation experiments also indicated that the molecularly imprinted TiO had larger adsorption capacity, better selectivity and higher photodegradation performance for diclofenac than non-imprinted TiO. The primary active species and degradation pathways during photodegradation process were also elucidated according to radical capture experiments and UPLC-MS-TOF technology. The prepared molecularly imprinted TiO has the advantages of efficient removal ability, high stability and environmental protection, so it has a wide application value in water treatment and water environmental restoration, especially when involved persistent toxic pollutants.
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http://dx.doi.org/10.1016/j.jhazmat.2020.124759DOI Listing
April 2021

The Impact of Periodontal Disease on Hospital Admission and Mortality During COVID-19 Pandemic.

Front Med (Lausanne) 2020 23;7:604980. Epub 2020 Nov 23.

Oral Biology, School of Dentistry, University of Leeds, Leeds, United Kingdom.

COVID-19 has had a huge impact on society and healthcare and it has been suggested that people with periodontal disease are at risk of having worse outcomes from the disease. The aim of this study was to quantify the impact of periodontal disease on hospital admission and mortality during the COVID-19 pandemic. The study extracted UK Biobank participants who had taken a COVID-19 test between March and June 2020 ( = 13,253), of which 1,616 were COVID-19 positive (12%) and 11,637 were COVID-19 negative (88%). Self-reported oral health indicators of painful or bleeding gums and loose teeth were used as surrogates for periodontal disease, participants who did not report any of the aforementioned indicators were used as controls. Multivariable logistic regressions were used to obtain crude and adjusted odds ratios of COVID-19 infection, subsequent hospital admission and mortality adjusted for demographics, BMI, biomarkers, lifestyle and co-morbidities. Painful gums, bleeding gums and loose teeth were reported in 2.7, 11.2 and 3.3% of participants with COVID-19 infection, respectively. Risk of COVID-19 infection in participants with painful or bleeding gums and loose teeth compared to controls was not increased (odds ratio [OR]: 1.10, 95% CI: 0.72-1.69; OR: 1.15, 95% CI: 0.84-1.59). COVID-19 positive participants with painful or bleeding gums had a higher risk of mortality (OR: 1.71, 95% CI: 1.05-2.72) but not hospital admission (OR: 0.90, 95% CI: 0.59-1.37). Participants with loose teeth did not show higher risk of hospital admission or mortality compared to the control group (OR = 1.55, 95% CI: 0.87-2.77; OR: 1.85; 95% CI: 0.92-2.72). There was insufficient evidence to link periodontal disease with an increased risk of COVID-19 infection. However, amongst the COVID-19 positive, there was significantly higher mortality for participants with periodontal disease. Utilization of linked dental and hospital patient records would improve the understanding of the impact of periodontal disease on COVID-19 related outcomes.
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http://dx.doi.org/10.3389/fmed.2020.604980DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7719810PMC
November 2020

Co-electrospun nano-/microfibrous composite scaffolds with structural and chemical gradients for bone tissue engineering.

Mater Sci Eng C Mater Biol Appl 2021 Feb 13;119:111622. Epub 2020 Oct 13.

College of Textile Science and Engineering, Zhejiang Sci-Tech University, Hangzhou 310018, PR China. Electronic address:

Recent trends in scaffold design for tissue engineering have focused on providing structural, mechanical and chemical cues for guiding cell behaviors. In this study, we presented a structural/compositional gradient nano-/microfibrous mesh by co-electrospinning, using silk fibroin-poly(ε-caprolactone) (SF-PCL) nanofibers and PCL microfibers. The pore size, porosity, and physical property of the gradient meshes were qualified. Cell proliferation of mouse osteoblast-like MC3T3-E1 cells was carried out to estimate the effect of structural and compositional gradients on biocompatibility. Furthermore, the 2-D mesh was rolled up and the compressive property of 3-D cylinder was investigated. The results suggested that the rolled-up gradient cylinder scaffold exhibited higher osteogenic differentiation compared to the pristine nanofibrous cylinder sample. By incorporating Chinese medicine ginsenoside Rg1, sustained release was achieved in composite meshes. Rg1-containing nanofibrous meshes and Rg1 gradient cylinders enhanced the cell proliferation of human umbilical vein endothelial cells (HUVECs). The developed fibrous scaffold may provide structural, compositional, and chemical gradients for bone regeneration. BRIEFS: Structural and chemical gradient fibrous scaffold fabricated by co-electrospinning.
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http://dx.doi.org/10.1016/j.msec.2020.111622DOI Listing
February 2021

Application of Fourier transform ion cyclotron resonance mass spectrometry in deciphering molecular composition of soil organic matter: A review.

Sci Total Environ 2021 Feb 27;756:144140. Epub 2020 Nov 27.

Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China. Electronic address:

Swiftly deciphering soil organic matter (SOM) composition is critical for research on soil degradation and restoration. Recent advances in analytical techniques (e.g., optical methods and mass spectrometry) have expanded our understanding of the composition, origin, and evolution of SOM. In particular, the use of Fourier transform ion cyclotron resonance mass spectrometers (FTICR-MS) makes it possible to interpret SOM compositions at the molecular level. In this review, we discuss extraction, enrichment, and purification methods for SOM using FTICR-MS analysis; summarize ionization techniques, FTICR-MS mechanisms, data analysis methods, and molecular compositions of SOM in different environments (providing new insights into its origin and evolution); and discuss factors affecting its molecular diversity. Our results show that digenesis, combustion, pyrolysis, and biological metabolisms jointly contribute to the molecular diversity of SOM molecules. The SOM thus formed can further undergo photodegradation during transportation from land to fresh water (and subsequently oceans), resulting in the formation of dissolved organic matter (DOM). Better understanding the molecular features of DOM therefore accelerates our understanding of SOM evolution. In addition, we assess the degradation potential of SOM in different environments to better inform soil remediation methods. Finally, we discuss the merits and drawbacks of applying FTICR-MS on the analysis of SOM molecules, along with existing gaps in knowledge, challenges, and new opportunities for research in FTICR-MS applications and SOM identification.
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http://dx.doi.org/10.1016/j.scitotenv.2020.144140DOI Listing
February 2021

The Dental Team: An Additional Resource for Delivering Vaccinations.

Front Med (Lausanne) 2020 6;7:606242. Epub 2020 Nov 6.

School of Dentistry, University of Leeds, Leeds, United Kingdom.

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http://dx.doi.org/10.3389/fmed.2020.606242DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7677565PMC
November 2020

Intermedin Alleviates Renal Ischemia-Reperfusion Injury and Enhances Neovascularization in Wistar Rats.

Drug Des Devel Ther 2020 10;14:4825-4834. Epub 2020 Nov 10.

Department of Nephrology, The Affiliated People's Hospital of Shanxi Medical University, Shanxi Provincial People's Hospital, Shanxi Kidney Disease Institute, Taiyuan, Shanxi, People's Republic of China.

Background: Ischemia-reperfusion injury (IRI) is a major cause of acute kidney injury (AKI) and increases the risk of subsequently developing chronic kidney disease. Angiogenesis has been shown to play an important role in reducing renal injury after ischemia reperfusion. In this study, we investigated whether IMD could reduce renal IRI by promoting angiogenesis.

Methods: The kidneys of Wistar rats were subjected to 45 min of warm ischemia followed by 24 h of reperfusion. IMD was overexpressed in vivo using the vector pcDNA3.1-IMD transfected by an ultrasound-mediated system. The renal injury after ischemia reperfusion was assessed by detection of the serum creatinine concentration and histologic examinations of renal tissues stained by PAS and H&E. Real-time PCR and Western blotting were used to determine the mRNA and protein levels, respectively. Histological examinations were used to assess the expression of CD31, MMP2, MMP9, ET-1, VEGF and VEGFR2 in tissues.

Results: Renal function and renal histological damage were significantly ameliorated in IMD-transfected rats after ischemia reperfusion. Compared to the IRI, IMD significantly promoted angiogenesis. IMD also upregulated the protein and mRNA expression levels of VEGF and VEGFR2 and downregulated the expression level of MMP2, MMP9 and ET-1.

Conclusion: IMD could protect the kidney after renal ischemia-reperfusion injury by promoting angiogenesis and reducing the destruction of the perivascular matrix.
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http://dx.doi.org/10.2147/DDDT.S253019DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7666991PMC
November 2020

Transcriptional signatures of the small intestinal mucosa in response to ethanol in transgenic mice rich in endogenous n3 fatty acids.

Sci Rep 2020 11 16;10(1):19930. Epub 2020 Nov 16.

Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, University of Louisville, 505 Hancock St., Louisville, KY, 40202, USA.

The intestine interacts with many factors, including dietary components and ethanol (EtOH), which can impact intestinal health. Previous studies showed that different types of dietary fats can modulate EtOH-induced changes in the intestine; however, mechanisms underlying these effects are not completely understood. Here, we examined intestinal transcriptional responses to EtOH in WT and transgenic fat-1 mice (which endogenously convert n6 to n3 polyunsaturated fatty acids [PUFAs]) to identify novel genes and pathways involved in EtOH-associated gut pathology and discern the impact of n3 PUFA enrichment. WT and fat-1 mice were chronically fed EtOH, and ileum RNA-seq and bioinformatic analyses were performed. EtOH consumption led to a marked down-regulation of genes encoding digestive and xenobiotic-metabolizing enzymes, and transcription factors involved in developmental processes and tissue regeneration. Compared to WT, fat-1 mice exhibited a markedly plastic transcriptome response to EtOH. Cell death, inflammation, and tuft cell markers were downregulated in fat-1 mice in response to EtOH, while defense responses and PPAR signaling were upregulated. This transcriptional reprogramming may contribute to the beneficial effects of n3 PUFAs on EtOH-induced intestinal pathology. In summary, our study provides a reference dataset of the intestinal mucosa transcriptional responses to chronic EtOH exposure for future hypothesis-driven mechanistic studies.
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http://dx.doi.org/10.1038/s41598-020-76959-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7670449PMC
November 2020

Analysis of 2019-nCoV receptor ACE2 expression in different tissues and its significance study.

Ann Transl Med 2020 Sep;8(17):1077

Department of Otolaryngology, the First Affiliated Hospital of China Medical University, Shenyang, China.

Background: On March 11, 2020, the World Health Organization (WHO) officially announced that the coronavirus disease 2019 (COVID-19) had reached global pandemic status. Current studies have found that angiotensin-converting enzyme 2 (ACE2) is a cell surface receptor of the novel coronavirus that plays a vital role in the pathogenesis of COVID-19. It is of immense importance for the prevention of virus transmission and treatment to clarify the distribution and expression of ACE2 in various tissues and organs of the body.

Methods: RNAseq transcriptome data and sex data were obtained from the genotype-tissue expression (GTEx) and the Cancer Genome Atlas (TCGA) databases. We separately analyzed the distribution of ACE2 expression in different tissues in the GTEx and TCGA database, and explored the correlation between sex and ACE2 expression levels. Next, the expression levels of ACE2 in different tissues and organs and its correlation with sex were analyzed once again after combing all samples from the two databases.

Results: ACE2 expression data were collected from the GTEx database for 6738 normal tissues. Six hundred eighteen tumor tissue data were collected from the TCGA database. The results of the analysis are consistent from different databases. The results indicated that the expression of ACE2 was the highest in the small intestines, higher in tissues such as salivary glands in the testicular, kidney, heart, thyroid and adipose tissues, while the expression of ACE2 was lower in tissues such as the spleen, brain, muscle, pituitary, and skin. There were no significant differences in the expression of ACE2 in the different organs when it came to the individual's sex.

Conclusions: Our study deeply explored the distribution and expression of ACE2 in various tissues of the human body. The tissues and organs with high ACE2 expression were consistent with the current clinical and basic research results of the novel coronavirus. Our study is conducive to the discovery of potential target organs for viral infection, to provide a reference for the development of clinical progress of patients with novel coronavirus infection.
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http://dx.doi.org/10.21037/atm-20-4281DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7576005PMC
September 2020

Risk of incident cardiovascular disease in people with periodontal disease: A systematic review and meta-analysis.

Clin Exp Dent Res 2021 Feb 30;7(1):109-122. Epub 2020 Oct 30.

School of Dentistry, University of Leeds, Leeds, UK.

Objectives: Cardiovascular disease (CVD) is a major cause of mortality; periodontal disease (PD) affects up to 50% of the world's population. Observational evidence has demonstrated association between CVD and PD. Absent from the literature is a systematic review and meta-analysis of longitudinal cohort studies quantifying CVD risk in PD populations compared to non-PD populations. To examine the risk of incident CVD in people with PD in randomised controlled trials and longitudinal cohort studies.

Material And Methods: We searched Medline, EMBASE and Cochrane databases up to 9th Oct 2019 using keywords and MeSH headings using the following concepts: PD, CVD, longitudinal and RCT study design. CVD outcomes included but were not restricted to any CVD, myocardial infarction, coronary heart disease (CHD) and stroke. Diagnosis method and severity of PD were measured either clinically or by self-report. Studies comparing incident CVD in PD and non-PD populations were included. Meta-analysis and meta-regression was performed to determine risk of CVD in PD populations and examine the effects of PD diagnosis method, PD severity, gender and study region.

Results: Thirty-two longitudinal cohort studies were included after full text screening; 30 were eligible for meta-analysis. The risk of CVD was significantly higher in PD compared to non-PD (relative risk [RR]: 1.20, 95% CI: 1.14-1.26). CVD risk did not differ between clinical or self-reported PD diagnosis (RR = 0.97, 95% CI: 0.87-1.07,). CVD risk was higher in men (RR: 1.16, 95% CI: 1.08-1.25) and severe PD (RR: 1.25, 95% CI: 1.15-1.35). Among all types of CVD, the risk of stroke was highest (RR = 1.24; 95% CI:1.12-1.38), the risk of CHD was also increased (RR = 1.14; 95% CI:1.08-1.21).

Conclusion: This study demonstrated modest but consistently increased risk of CVD in PD populations. Higher CVD risk in men and people with severe PD suggests population-targeted interventions could be beneficial.
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http://dx.doi.org/10.1002/cre2.336DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7853902PMC
February 2021

UV/ peroxymonosulfate process for degradation of chloral hydrate: Pathway and the role of radicals.

J Hazard Mater 2021 01 2;401:123837. Epub 2020 Sep 2.

Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China. Electronic address:

In this study, kinetics, influencing factors and potential mechanisms involved in the degradation of chloral hydrate (CH) by UV/peroxymonosulfate (PMS) process were demonstrated. The degradation rate of CH could reach 89.6% by UV/PMS process, significantly exceeding UV/PMS (0.7%), UV/PMS (6.3%), UV direct photolysis (9.0%) and PMS alone (0.0%) processes. CH degradation in UV/PMS system followed pseudo first-order degradation kinetics with an apparent rate constant of 0.186 min, which was suppressed by Cl and HCO. The optimal pH for CH degradation was around 5.0. Direct mineralization accounted for the CH degradation in UV/PMS system. Interestingly, the addition of PMS at the neutral condition before UV irradiation transferred CH into trichloroacetic acid (TCAA). The transformation efficiency of CH into TCAA at 10 min was enhanced from 2.17%-40.38% with the elevation of initial pH from 7.0-8.0. The subsequent exposure of UV lamps ceased the transformation of CH into TCAA and facilitated the direct mineralization of CH, but it did not work in the refractory TCAA degradation. Finally, it was revealed that HO predominantly participated CH degradation in UV/PMS process, while O was responsible for the transformation of CH into TCAA by addition of PMS before UV irradiation.
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http://dx.doi.org/10.1016/j.jhazmat.2020.123837DOI Listing
January 2021

[Research Progress on Biological Properties of Natural Killer Cells and Their Application in B Cell Lymphoma--Review].

Zhongguo Shi Yan Xue Ye Xue Za Zhi 2020 Oct;28(5):1782-1786

Department of Hematology, The First Affiliated Hospital of Nanchang University, Nanchang 330006, Jiangxi Province, China,E-mail:

B cell lymphoma is a group of very heterogeneous biologically complex malignancies, which originates from lymph nodes with different kinds of clinical and biologic characteristics. B cell lyphoma can occur in every part of body, and accouting for more than 80% of cell lyphomas. Natural killer (NK) is the impartant composition cell of immune system, which can fast response to the targeting cells, such as tumour cells or cells infected by virus without sensitization, NK cells play an important role in the early innate immunity. Compelling evidences shows that NK cells play an important role in occurrence, development and treatment of B cell lyphoma, and B cell lymphoma can be inhibitied by advanced and impoved NK cells. In this review, the biologic characteristics and role of NK cells in B cell lyphoma was summrized briefly.
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http://dx.doi.org/10.19746/j.cnki.issn.1009-2137.2020.05.058DOI Listing
October 2020

Structure activity relationship study of N-doped ligand modified Fe(III)/HO for degrading organic pollutants.

J Hazard Mater 2021 02 30;404(Pt A):124142. Epub 2020 Sep 30.

State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China. Electronic address:

The performance of Fe(III)/HO was extremely enhanced by a novel N-doped ligand dipicolinamide (Dpa) for removing various organic pollutants. This dramatic enhancement of contaminants degradation in Fe(III)-Dpa/HO system under pH≥ 7 was ascribed to the coordinating capacity of Dpa to form the dissolved Fe(III)-Dpa/Fe(II)-Dpa, and the reductive capacity of Dpa to maintain the concentration of Fe(II), which made Dpa improve the catalytic performance of Fe(III) nearly twice as much as Fe(II). Dpa has a strong complexing ability than Cit, NTA, and EDTA to maintain the catalytic activity of Fe(III) without light. The single crystal of Fe-Dpa was obtained to reveal its structure activity relationship. Fe-Dpa was composed of four bonds of Fe-N and two bonds of Fe-Cl. The Fe-Cl bonds were labile sites, which was easily experienced ligand exchange with HO, resulting Fe-HO bonds to initiate degradation reaction. The remaining Fe-N bonds were effectively planar, which had a large delocalized π electrons flow domain, enhancing the production of multiple reactive species, including iron(IV/V)-oxo species, HO· and O·. An empirical kinetic model of Fe(III)-Dpa/HO system was established. In addition, the evaluation results of the toxicity of Fe-Dpa to larval zebrafish and chinese cabbage displayed that Fe-Dpa possesses low toxicity.
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http://dx.doi.org/10.1016/j.jhazmat.2020.124142DOI Listing
February 2021

Impact of hydraulic retention time on swine wastewater treatment by aerobic granular sludge sequencing batch reactor.

Environ Sci Pollut Res Int 2021 Feb 26;28(5):5927-5937. Epub 2020 Sep 26.

State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China.

In this study, the effect of hydraulic retention time (HRT) on the performance of aerobic granular sludge (AGS) treating swine wastewater (SW) in sequencing batch reactor (SBR) was investigated. The HRT was set at 4.8, 6, 8, 12, and 16 h and performed in five parallel aerobic granular sludge sequence batch reactors (AGSBRs), respectively. The results showed that sedimentation performance and biomass concentration were improved by decreasing the HRT from 16 to 8 h. However, when further decreasing HRT from 8 to 4.8 h, the AGS performance became worse. The AGS process with HRT of 8 h exhibited high pollutant removal efficiency, and an abundant microbial community and a stable microbial community structure were observed. High-throughput 16S rRNA analysis revealed that there were significant differences between the microorganisms in AGS samples with HRT of 8 h at the phylum level and that the dominant microbes changed as the process proceeded. At the genus level, the species and relative abundance of microorganisms gradually evolved for AGS stability in all cases.
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http://dx.doi.org/10.1007/s11356-020-10922-wDOI Listing
February 2021

Integration of innate immune signalling by caspase-8 cleavage of N4BP1.

Nature 2020 11 24;587(7833):275-280. Epub 2020 Sep 24.

Department of Physiological Chemistry, Genentech, South San Francisco, CA, USA.

Mutations in the death receptor FAS or its ligand FASL cause autoimmune lymphoproliferative syndrome, whereas mutations in caspase-8 or its adaptor FADD-which mediate cell death downstream of FAS and FASL-cause severe immunodeficiency in addition to autoimmune lymphoproliferative syndrome. Mouse models have corroborated a role for FADD-caspase-8 in promoting inflammatory responses, but the mechanisms that underlie immunodeficiency remain undefined. Here we identify NEDD4-binding protein 1 (N4BP1) as a suppressor of cytokine production that is cleaved and inactivated by caspase-8. N4BP1 deletion in mice increased the production of select cytokines upon stimulation of the Toll-like receptor (TLR)1-TLR2 heterodimer (referred to herein as TLR1/2), TLR7 or TLR9, but not upon engagement of TLR3 or TLR4. N4BP1 did not suppress TLR3 or TLR4 responses in wild-type macrophages, owing to TRIF- and caspase-8-dependent cleavage of N4BP1. Notably, the impaired production of cytokines in response to TLR3 and TLR4 stimulation of caspase-8-deficient macrophages was largely rescued by co-deletion of N4BP1. Thus, the persistence of intact N4BP1 in caspase-8-deficient macrophages impairs their ability to mount robust cytokine responses. Tumour necrosis factor (TNF), like TLR3 or TLR4 agonists, also induced caspase-8-dependent cleavage of N4BP1, thereby licensing TRIF-independent TLRs to produce higher levels of inflammatory cytokines. Collectively, our results identify N4BP1 as a potent suppressor of cytokine responses; reveal N4BP1 cleavage by caspase-8 as a point of signal integration during inflammation; and offer an explanation for immunodeficiency caused by mutations of FADD and caspase-8.
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http://dx.doi.org/10.1038/s41586-020-2796-5DOI Listing
November 2020

Unstable Mechanisms of Resistance to Inhibitors of Escherichia coli Lipoprotein Signal Peptidase.

mBio 2020 09 8;11(5). Epub 2020 Sep 8.

Department of Infectious Diseases, Genentech, South San Francisco, California, USA

Clinical development of antibiotics with novel mechanisms of action to kill pathogenic bacteria is challenging, in part, due to the inevitable emergence of resistance. A phenomenon of potential clinical importance that is broadly overlooked in preclinical development is heteroresistance, an often-unstable phenotype in which subpopulations of bacterial cells show decreased antibiotic susceptibility relative to the dominant population. Here, we describe a new globomycin analog, G0790, with potent activity against the type II signal peptidase LspA and uncover two novel resistance mechanisms to G0790 in the clinical uropathogenic strain CFT073. Building on the previous finding that complete deletion of Lpp, the major Gram-negative outer membrane lipoprotein, leads to globomycin resistance, we also find that an unexpectedly modest decrease in Lpp levels mediated by insertion-based disruption of regulatory elements is sufficient to confer G0790 resistance and increase sensitivity to serum killing. In addition, we describe a heteroresistance phenotype mediated by genomic amplifications of that result in increased LspA levels sufficient to overcome inhibition by G0790 in culture. These genomic amplifications are highly unstable and are lost after as few as two subcultures in the absence of G0790, which places amplification-containing resistant strains at high risk of being misclassified as susceptible by routine antimicrobial susceptibility testing. In summary, our study uncovers two vastly different mechanisms of resistance to LspA inhibitors in and emphasizes the importance of considering the potential impact of unstable and heterogenous phenotypes when developing antibiotics for clinical use. Despite increasing evidence suggesting that antibiotic heteroresistance can lead to treatment failure, the significance of this phenomena in the clinic is not well understood, because many clinical antibiotic susceptibility testing approaches lack the resolution needed to reliably classify heteroresistant strains. Here we present G0790, a new globomycin analog and potent inhibitor of the type II signal peptidase LspA. We demonstrate that in addition to previously known mechanisms of resistance to LspA inhibitors, unstable genomic amplifications containing can lead to modest yet biologically significant increases in LspA protein levels that confer a heteroresistance phenotype.
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http://dx.doi.org/10.1128/mBio.02018-20DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7482066PMC
September 2020