Publications by authors named "Xiaoyong Zhang"

291 Publications

Noncanonical NF-κB Signaling Pathway in Liver Diseases.

J Clin Transl Hepatol 2021 Feb 21;9(1):81-89. Epub 2020 Dec 21.

State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Laboratory of Viral Hepatitis Research, Department of Infectious Diseases, Nanfang Hospital, Southern Medical University, Guangzhou,Guangdong, China.

The noncanonical NF-κB signaling pathway is an important branch of NF-κB signaling. It is involved in regulating multiple important biological processes, including inflammation and host immune response. A central adaptor protein of the noncanonical NF-κB pathway is NF-κB-inducing kinase (NIK), which activates the downstream kinase IKKα to process p100 to p52, thereby forming the RelB/p52 heterodimer to initiate the expression of target genes. Currently, many specific inhibitors and monoclonal antibodies targeting or triggering this pathway are being developed and tested for various diseases, including cancers, autoimmune diseases, and virus infection. Given that aberrant activation of the noncanonical NF-κB pathway is frequently observed in various liver diseases, targeting this pathway may be a promising therapeutic strategy to alleviate liver inflammation. Moreover, activation of this pathway may contribute to the antiviral immune response and promote the clearance of persistent hepatotropic virus infection. Here, we review the role of the noncanonical NF-κB pathway in the occurrence and development of different liver diseases, and discuss the potency and application of modulating the noncanonical NF-κB pathway for treatment of these liver diseases.
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http://dx.doi.org/10.14218/JCTH.2020.00063DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7868705PMC
February 2021

Bioactive aromatic butenolides from a mangrove sediment originated fungal species, Aspergillus terreus SCAU011.

Fitoterapia 2021 Feb 11;150:104856. Epub 2021 Feb 11.

School of Biological Science and Technology, University of Jinan, 336 West Road of Nan Xinzhuang, Jinan 250022, China. Electronic address:

Seven new compounds including five aromatic butenolide analogues (1-5), one quinazolinone alkaloid (6) and one benzoic acid derivative (7), along with eleven known co-metabolites (8-18), were isolated from Aspergillus terreus SCAU011, a fungus from the rhizosphere sediment of a mangrove plant Rhizophora stylosa. The structures of these isolates were established by a combination of MS, NMR and ECD data analyses, as well as chemical method. Compound 3 is a rare ring-open aromatic butenolide, while 6 represents the first natural ring-open benzomalvin-type quinazolinone alkaloid. Also, the previously reported structures for asperlides A-C were proposed to be revised in the present work. The COX-2 inhibitory, α-glucosidase inhibitory, antioxidant and antibacterial activities of all the compounds were assessed. While compounds 4, 6, 11 and 18 exhibited better COX-2 inhibitory activity than the positive control celecoxib, compounds 9 and 10 showed significant α-glucosidase inhibitory activity with IC values of 56.1 and 12.9 μM, respectively. Meanwhile, half of the tested samples (1, 8-11 and 15-17) exerted similar or better antioxidant activity compared with the reference drug curcumin, and compounds 3, 9, 17 and 18 displayed moderate antibacterial effect against Staphylococcus aureus.
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http://dx.doi.org/10.1016/j.fitote.2021.104856DOI Listing
February 2021

Research on DOA Estimation Based on Acoustic Energy Flux Detection Using a Single MEMS Vector Hydrophone.

Micromachines (Basel) 2021 Feb 8;12(2). Epub 2021 Feb 8.

State Key Laboratory of Dynamic Testing Technology, North University of China, Taiyuan 030051, China.

The principle of acoustic energy flux detection method using a single micro electromechanical system (MEMS) vector hydrophone is analyzed in this paper. The probability distribution of acoustic energy flux and the weighted histogram algorithm are discussed. Then, an improved algorithm is proposed. Based on the algorithm, the distribution range of the energy is obtained by a sliding window, the energy center of gravity in the range is considered as the result of direction of arrival (DOA) estimation, and it is proved to be the maximum likelihood estimation of the target direction. The simulation results show that, with the signal to noise ratio (SNR) from -10 dB to 10 dB, the root mean square error (RMSE) of the improved algorithm is reduced by 47.8% on average, and is more accurate in the presence of interference. The experimental results of lake test are consistent with the theory analysis and simulation results.
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http://dx.doi.org/10.3390/mi12020168DOI Listing
February 2021

Influence of Isothermal ω Transitional Phase-Assisted Phase Transition From β to α on Room-Temperature Mechanical Performance of a Meta-Stable β Titanium Alloy Ti-10Mo-6Zr-4Sn-3Nb (Ti-B12) for Medical Application.

Front Bioeng Biotechnol 2020 20;8:626665. Epub 2021 Jan 20.

Institute of Advanced Wear and Corrosion Resistant and Functional Materials, Jinan University, Guangzhou, China.

The microstructural evolution and tensile performance of a meta-stable β-type biomedical Ti-10Mo-6Zr-4Sn-3Nb (Ti-B12) alloy subjected to one-stage aging (OSA) and two-stage aging (TSA) are investigated in this work. The OSA treatment is performed at 510°C for 8 h. The TSA treatments are composed of low-temperature aging and high-temperature aging. In the first step, low-temperature aging is conducted at 325°C for 2 h. In the second step, the aging temperature is the same as that in the OSA. The result of the microstructure evolution shows that the precipitated secondary phase after aging is mainly influenced by the process of phase transition. There is a marked difference in the microstructure of the Ti-B12 alloy subjected to the OSA and TSA treatments. The needle-shaped α phases are precipitated in the parent β phase after the OSA treatment. Conversely, the short shuttle-like α phases precipitated after the TSA treatment are formed in the β matrix with the aid of the role of the isothermal ω transitional phase-assisted phase transition. The electron backscattered diffraction results indicate that the crystallographic orientation relationship of the α phases precipitated during the TSA treatment is basically analogous to those in the OSA treatment. The relatively higher tensile strength of 1,275 MPa is achieved by strengthening the effect of the short shuttle-like α precipitation with a size of 0.123 μm in length during the TSA treatment, associating with a suitable elongation of 12% at room temperature simultaneously. The fracture surfaces of the samples after the OSA and TSA treatments indicate that preventing the coarsening of the α layers in the grain boundaries is favorable for the enhancement of strength of Ti-B12 at room temperature. MTT test was carried out to evaluate the acute cytotoxicity and biocompatibility of the implanted material using L929 cells. The relative proliferation rates of cytotoxicity levels 0, 1, 2, 3, and 4 are ≥100, 80-99, 50-79, 30-49, and 0-29%, respectively. The cytotoxicity of the Ti-B12 alloy is slightly better than that of the Ti-6Al-4V alloy, which can meet the requirements of medical materials for biomedical materials.
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http://dx.doi.org/10.3389/fbioe.2020.626665DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7855458PMC
January 2021

Vibrational Energy Relaxation of Deuterium Fluoride in -Dichloromethane: Insights from Different Potentials.

J Chem Theory Comput 2021 Feb 8. Epub 2021 Feb 8.

Department of Chemistry and Division of Quantum Chemistry and Physical Chemistry, KU Leuven, Celestijnenlaan 200F, Leuven B-3001, Belgium.

Vibrationally excited deuterium fluoride (DF) formed by fluorine atom reaction with a solvent was found (, , 347, 530) to relax rapidly (less than 10 ps) in acetonitrile- (CDCN) and dichloromethane- (CDCl). However, insights into how CDCl facilitates this energy relaxation have so far been lacking, given the weak interaction between DF and a single CDCl. In this work, we report the results of reactive simulations with a two-state reactive empirical valence bond (EVB) potential to study the energy deposited into nascent DF after transition-state passage and of nonequilibrium molecular dynamics simulations using multiple different potential energy functions to model the relaxation dynamics. For these second simulations, we used the standard Merck molecular force field (MMFF) potential, an MMFF-based covalent-ionic empirical valence bond (EVB) potential (EVB), a newly developed potential [referred to as MMFF(rDF)] which extends upon the MMFF potential by making the DF/CDCl interaction depend on the value of the D-F bond stretching coordinate and by taking the anisotropic charge distribution of the solvent molecules into account, the polarizable atomic multipole optimized energetics for biomolecular applications (AMOEBA) potential, and the quantum mechanics/molecular mechanics (QM/MM) potential. The relaxation is revealed to be highly sensitive to the potential used. Neither standard MMFF nor EVB reproduces the experimentally observed rapid relaxation dynamics, and they also fail to provide a good description of the interaction potential between DF and CDCl as calculated using CCSD(T)-F12. This is attributed to the use of a point-charge model for the solute and to failing to model the anisotropic electrostatic properties of CDCl. The MMFF(rDF), AMOEBA, and QM/MM potentials all reproduce the CCSD(T)-F12 two-body DF---CDCl interaction potential rather well but only with the QM/MM approach is fast vibrational relaxation obtained (lifetimes of ∼288, ∼186, and ∼8 ps, respectively), which we attribute to differences in the solute-solvent local structure. With QM/MM, a unique "many-body" interaction pattern in which DF is in close contact with two solvent Cl atoms and more than three solvent D atoms is found, but this structure is not seen with other potentials. The QM/MM dynamics also display enhanced solute-solvent interactions with vibrationally excited DF that induce a DF band redshift and hence a resonant overlap with solvent C-D modes, which facilitate the intermolecular energy transfer. Our work also suggests that potentials used to model energy relaxation need to capture the fine structure of solute-solvent interactions and not just the two-body part.
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http://dx.doi.org/10.1021/acs.jctc.0c01059DOI Listing
February 2021

Recent Advances on Fabrication of Polymeric Composites Based on Multicomponent Reactions for Bioimaging and Environmental Pollutant Removal.

Macromol Rapid Commun 2021 Feb 4:e2000563. Epub 2021 Feb 4.

Department of Chemistry and the Tsinghua Center for Frontier Polymer Research, Tsinghua University, Beijing, 100084, P. R. China.

As the core of polymer chemistry, manufacture of functional polymers is one of research hotspots over the past several decades. Various polymers are developed for diverse applications due to their tunable structures and unique properties. However, traditional step-by-step preparation strategies inevitably involve some problems, such as separation, purification, and time-consuming. The multicomponent reactions (MCRs) are emerging as environmentally benign synthetic strategies to construct multifunctional polymers or composites with pendant groups and designed structures because of their features, such as efficient, fast, green, and atom economy. This mini review summarizes the latest advances about fabrication of multifunctional fluorescent polymers or adsorptive polymeric composites through different MCRs, including Kabachnik-Fields reaction, Biginelli reaction, mercaptoacetic acid locking imine reaction, Debus-Radziszewski reaction, and Mannich reaction. The potential applications of these polymeric composites in biomedical and environmental remediation are also highlighted. It is expected that this mini-review will promote the development preparation and applications of functional polymers through MCRs.
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http://dx.doi.org/10.1002/marc.202000563DOI Listing
February 2021

Cooperative search for dynamic targets by multiple UAVs with communication data losses.

ISA Trans 2021 Jan 2. Epub 2021 Jan 2.

College of Marine Electrical Engineering, Dalian Maritime University, Dalian, 116026, China. Electronic address:

This paper studies the problem of cooperative searching for dynamical moving targets by multiple unmanned aerial vehicles (UAVs). The environmental information possessed by UAVs is inconsistent due to packet losses of shared environmental information in communication channels and the discrepancies of detected information among different UAVs. To unify the environmental information among UAVs, the lost information is compensated for by an improved Least Square Method (LSM) which incorporates the target location model into the fitting function to enhance data fitting precision. The Weighted Averaging Method (WAM) is used to merge multiple source information where the weight coefficients are set based on the uncertain values of environmental information. To search for dynamic targets and then automatically re-enter into search areas for UAVs, a Modified Genetic Algorithm (MGA) and rolling optimization techniques are utilized to generate real-time paths for UAVs. Simulation results and comparison studies with existing methods validate the effectiveness of the above cooperative searching strategy.
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http://dx.doi.org/10.1016/j.isatra.2020.12.055DOI Listing
January 2021

Time-efficient and contrast-free magnetic resonance imaging approach to the diagnosis of deep vein thrombosis on black-blood gradient-echo sequence: a pilot study.

Quant Imaging Med Surg 2021 Jan;11(1):276-289

Department of Biomedical Engineering, The Sixth Affiliated Hospital, School of Basic Sciences, Guangzhou Medical University, Guangzhou, China.

Background: Black-blood thrombus imaging (BTI) has shown to be advantageous for the diagnosis of deep vein thrombosis (DVT). However, previous techniques using fast spin echo have a high specific absorption rate. As DANTE (delay alternating with nutation for tailored excitation) black-blood preparation can suppress blood flows over a broad range of velocities, we hypothesized that a DANTE black-blood preparation combined with a fast low-angle shot (FLASH) gradient-echo readout-DANTE-FLASH could be used to diagnose DVT.

Methods: Eleven healthy volunteers and 30 suspected DVT patients were recruited to undergo DANTE-FLASH and magnetic resonance direct thrombus imaging (MRDTI). The suspected DVT patients were also examined by ultrasound (US). For the segment level, a total of 1,066 venous vessel segments were analyzed. Using US and MRDTI as the references, the sensitivity (SE), specificity (SP), positive and negative predictive values (PPV and NPV), and accuracy (ACC) of DANTE-FLASH were calculated. To quantitatively compare image quality between DANTE-FLASH and MRDTI, image signal-to-noise ratio (SNR), apparent contrast-to-noise ratio (CNR) between muscle and the venous lumen, and the apparent CNR between the thrombus and venous lumen were measured. Additionally, diagnostic confidence, image quality, and clot burden were also evaluated.

Results: Using the consensus results of US and MRDTI as a standard reference, the diagnostic SE, SP, PPV, NPV, and ACC of DANTE-FLASH for the 2 readers were 97.0% and 93.2%, 99.0% and 98.2%, 93.4% and 87.9%, 99.6% and 99.0%, and 98.8% and 97.6%, respectively. According to the image quantitative analysis results, DANTE-FLASH demonstrated higher image SNR and CNR than MRDTI. The image quality and diagnostic confidence scores of DANTE-FLASH were higher than MRDTI (3.66±0.44 3.52±0.52, P<0.001, and 3.84±0.36 3.76±0.41, P<0.001). There was excellent agreement between DANTE-FLASH and MRDTI on clot burden evaluation.

Conclusions: DANTE-FLASH provided better image quality than MRDTI and accurately detected thrombi. It may, therefore, serve as a safe and convenient alternative for the diagnosis of DVT.
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http://dx.doi.org/10.21037/qims-19-761DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7719944PMC
January 2021

An integrated study of metabolomics and transcriptomics to reveal the anti-primary dysmenorrhea mechanism of Akebiae Fructus.

J Ethnopharmacol 2021 Apr 28;270:113763. Epub 2020 Dec 28.

The National Pharmaceutical Engineering Center (NPEC) for Solid Preparation in Chinese Herbal Medicine, Jiangxi University of Traditional Chinese Medicine, 56 Yangming Road, Jiangxi, Nanchang, 330006, China. Electronic address:

Ethnopharmacological Relevance: Akebiae Fructus, a Tujia minority folk medicine and a well-known traditional Chinese medicine for soothing the liver, regulating Qi, promoting blood circulation and relieving pain, is widely used in the treatment of primary dysmenorrhea. However, little is known about its underlying mechanism.

Aim Of The Study: To explore the effect of Akebiae Fructus on primary dysmenorrhea model induced by estradiol benzoate and oxytocin, and to provide better understanding of the mechanism of Akebiae Fructus for primary dysmenorrhea treatment.

Materials And Methods: The primary dysmenorrhea mouse model was used in this study. Except for the control group and the normal administration group, the mice of other groups were subcutaneously injected with estradiol benzoate (10 mg/kg/d) for 10 consecutive days. From the 5th day of the ten-day model period, the positive control groups were given 0.075 g/kg ibuprofen and 7.5 g/kg Leonurus granule, the drug groups were given 0.2 g/kg, 0.4 g/kg, 0.8 g/kg Akebiae Fructus extract, the normal administration group was given 0.8 g/kg Akebiae Fructus extract, and the same volume saline was given in the control group. On the tenth day, oxytocin (10 U/kg) was peritoneally injected after estradiol benzoate injected 1 h. After the oxytocin injection, writhing behavior was observed for 30 min. Then the uterine tissue was collected to measure the level of PGF and PGE, and for histological analysis and transcriptomics analysis. Meanwhile, plasma and urine samples were collected for metabolomic analysis.

Results: Akebiae Fructus inhibited the writhing, decreased the PGF level and ameliorated the morphological changes. 32 potential metabolic biomarkers in plasma and 17 in urine were found for primary dysmenorrhea, and after Akebiae Fructus treatment, 25 metabolites in plasma and 14 in urine were restored. These altered metabolites were mainly involved in lipid, amino acid and organic acid metabolism. For the transcriptomic study, a total of 2244 differentially expressed genes (1346 up-regulated and 898 down-regulated) were obtained between the control and model group, and 148 differentially expressed genes (DEGs) were found related with Akebiae Fructus treatment of primary dysmenorrhea. Correlation analysis was carried out based on the transcriptomic and metabolomic data. 5 differentially expressed genes (Plpp3, Sgpp2, Arg1, Adcy8, Ak5) were found related with the enrichment metabolic pathways. The mechanism by which Akebiae Fructus ameliorates primary dysmenorrhea may account for the regulation of the gene expression to control the key enzymes in the sphingolipid metabolism, arginine and proline metabolism, glycerophospholipid metabolism and purine metabolism, inhibiting the abnormal secretion of PGF, alleviating the uterine contraction and reducing inflammation and pain.

Conclusions: Akebiae Fructus could effectively alleviate the symptoms of primary dysmenorrhea, regulate metabolic disorders, and control the related gene expression in primary dysmenorrhea. The study may provide clues for further study of Akebiae Fructus treatment on primary dysmenorrhea.
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http://dx.doi.org/10.1016/j.jep.2020.113763DOI Listing
April 2021

A preliminary study of the association between colonization of microorganism on microplastics and intestinal microbiota in shrimp under natural conditions.

J Hazard Mater 2021 Apr 17;408:124882. Epub 2020 Dec 17.

Joint Laboratory of Guangdong Province and Hong Kong Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural Universtiy, Guangzhou 510641, China; Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou 510642, China. Electronic address:

The microplastics pollution in wild aquatic organisms has been described by many studies. However, few studies focused on the farmed ones and MPs impacts on their gut microbiota under natural conditions. Here, we present the first detection of MPs in shrimp ponds and Litopenaeus vannamei. We also globally, firstly and preliminarily investigate the association between colonization of microorganism on MPs and intestinal microbiota under natural conditions. Microplastics (5129 ± 1176 items/kg d.w.) in sediments were mainly pellets, mostly white and blue, and in size less than 1 mm. Microplastics (14.08 ± 5.70 items/g w.w.) in shrimps were higher than that in mostly wild aquatic organisms and positively correlated with that in sediments. Blue fibers in small size (<0.5 mm) were dominant in shrimps. The bacterial communities and their microbial function on MPs were similar with that in shrimp gut, with higher diversity and richness in bacteria communities colonized on MPs. Network analysis demonstrated that the colonization of microorganism on MPs were associated with shrimp intestinal microbiota. Results suggest that except for toxicity reported previously, the effects on intestinal microbiota induced by MPs were possibly because of the biofilm on their surfaces as well, causing notable impacts on aquatic animals.
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http://dx.doi.org/10.1016/j.jhazmat.2020.124882DOI Listing
April 2021

Microplastic pollution and its relationship with the bacterial community in coastal sediments near Guangdong Province, South China.

Sci Total Environ 2021 Mar 14;760:144091. Epub 2020 Dec 14.

College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China. Electronic address:

The ecological stress caused by microplastic (MP) pollution in marine environments has attracted global attention. However, few studies have investigated the relationship between MP pollution and the microbial community in natural sediments. This study was the first to systematically characterize MP pollution (i.e., its abundance, shape, size and color) and investigate its relationship with the bacterial community in coastal sediments from Guangdong, South China, by microscopic observation and Illumina sequencing. The results of this study indicated that the abundance of microplastics (MPs), which was 344 ± 24 items/kg in 33 coastal sediments from 11 sites from South China, represented a relatively high level of MP pollution. MPs with sizes of <0.5 m, 0.5-1.0 mm and 1-2 mm accounted for the highest proportion (75%) in the sediments. Fiber/film (82%) and white/blue (91%) were the dominant shapes and colors, respectively, in all MP samples. Furthermore, the abundances, three shapes (fiber, film and fragment), three sizes (<0.5 mm, 0.5-1.0 mm and 1-2 mm), and two colors (blue and white) of MPs displayed positive correlations with some potential pathogens, including Vibrio, Pseudomonas, Bacillus and Streptococcus, but exhibited negative correlations with an environmentally friendly bacterial genus, Sphingomonas (which degrades various hazardous organic compounds), indicating that MPs might increase the potential ecological risks of coastal sediments. Our results may help to elucidate the relationship between MP pollution and the microbial community in coastal sediments.
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http://dx.doi.org/10.1016/j.scitotenv.2020.144091DOI Listing
March 2021

Viral and Antibody Kinetics of COVID-19 Patients with Different Disease Severities in Acute and Convalescent Phases: A 6-Month Follow-Up Study.

Virol Sin 2020 Dec 22;35(6):820-829. Epub 2020 Dec 22.

State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Laboratory of Viral Hepatitis Research, Department of Infectious Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, 510000, China.

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread rapidly around the world, posing a major threat to human health and the economy. Currently, long-term data on viral shedding and the serum antibody responses in COVID-19 patients are still limited. Herein, we report the clinical features, viral RNA loads, and serum antibody levels in a cohort of 112 COVID-19 patients admitted to the Honghu People's Hospital, Hubei Province, China. Overall, 5.36% (6/112) of patients showed persistent viral RNA shedding (> 45 days). The peak viral load was higher in the severe disease group than in the mild group (median cycle threshold value, 36.4 versus 31.5; P = 0.002). For most patients the disappearance of IgM antibodies occurred approximately 4-6 weeks after symptoms onset, while IgG persisted for over 194 days after the onset of symptoms, although patients showed a 46% reduction in antibodies titres against SARS-CoV-2 nucleocapsid protein compared with the acute phase. We also studied 18 asymptomatic individuals with RT-qPCR confirmed SARS-CoV-2 infection together with 17 symptomatic patients, and the asymptomatic individuals were the close contacts of these symptomatic cases. Delayed IgG seroconversion and lower IgM seropositive rates were observed in asymptomatic individuals. These data indicate that higher viral loads and stronger antibody responses are related to more severe disease status in patients with SARS-CoV-2 infection, and the antibodies persisted in the recovered patient for more than 6 months so that the vaccine may provide protection against SARS-CoV-2 infection.
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http://dx.doi.org/10.1007/s12250-020-00329-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7754696PMC
December 2020

Mussel-inspired adhesive and conductive hydrogel with tunable mechanical properties for wearable strain sensors.

J Colloid Interface Sci 2021 Mar 13;585:420-432. Epub 2020 Oct 13.

Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada. Electronic address:

Hypothesis: Flexible and wearable hydrogel strain sensors have attracted significant attention for human activity monitoring and electronic skins. However, it remains a great challenge to develop an integrated hydrogel strain sensor showing intrinsic adhesive performances, tunable mechanical and high strain-sensitive properties. Marine mussels show a superior capacity to adhere to various substrates (including organic and inorganic), while polycaprolactone (PCL) can be easily modified into crosslinkers with different degrees of functionality (bi-, tri-, and quadri-functional groups) to control the crosslinking density. Therefore, the developed mussel-inspired 3,4-dihydroxyphenyl-l-alanine acrylamide-polycaprolactone (l-DMA-PCL) hydrogels could address these issues and serve as the potential wearable strain sensors for biomaterials and healthcare monitoring.

Experiments: l-DMA monomers were successfully crosslinked by functionalized PCL (bi-, tri-, and quadri-functional) using UV light (wavelength ~ 365 nm) to prepare the l-DMA-PCL hydrogel. Adhesive behaviors, tunable mechanical properties and strain sensing performances of the l-DMA-PCL hydrogels were systematically studied.

Findings: The l-DMA-PCL hydrogel exhibited reversible adhesion to various material substrates (including steel, aluminum, ceramics, poly(ethylene terephthalate) (PET), wood, rubber, even for polypropylene (PP) and polytetrafluoroethylene (PTFE)) as well as skin. Moreover, the mechanical properties (stress: 50.2-72.4 KPa, strain: 700-1140%, Young's modulus: 8.6-14.8 KPa, and toughness: 16.4-53.6 KJ/m) of the hydrogels could be readily tuned by the modulation of functionality degree (bi-, tri-, and quadri-functional) of PCL. Intriguingly, the hydrogel-based wearable strain sensor showing high conductivity (0.0550 S/cm) and sensitive responses to both large (e.g., joint bending) and subtle human motions (e.g., frowning and speaking). Based on these achievements, this work provides new insights into the development of hydrogel with adhesiveness, controllable mechanical performance and high strain sensitivity as a flexible and wearable hydrogel strain sensors.
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http://dx.doi.org/10.1016/j.jcis.2020.10.023DOI Listing
March 2021

Fabrication of claviform fluorescent polymeric nanomaterials containing disulfide bond through an efficient and facile four-component Ugi reaction.

Mater Sci Eng C Mater Biol Appl 2021 Jan 25;118:111437. Epub 2020 Aug 25.

Department of Chemistry and the Tsinghua Center for Frontier Polymer Research, Tsinghua University, Beijing 100084, China; Department of Chemistry and Center for Nanotechnology and Institute of Biomedical Technology, Chung-Yuan Christian University, Chung-Li 32023, Taiwan. Electronic address:

Multicomponent reactions (MCRs) have attracted broad interest for preparation of functional nanomaterials especially for the synthesis of functional polymers. Herein, we utilized an "old" MCR, the four-component Ugi reaction, to synthesize disulfide bond containing poly(PEG-TPE-DTDPA) amphiphilic copolymers with aggregation-induced emission (AIE) feature. This four-component Ugi reaction was carried out under rather mild reaction conditions, such as room temperature, no gas protection and absent of catalysts. The amphiphilic poly(PEG-TPE-DTDPA) copolymers with high number-average molecular weight (up to 86,440 Da) can self-assemble into claviform fluorescent polymeric nanoparticles (FPNs) in aqueous solution, and these water-dispersed nanoparticles exhibited strong emission, large Stokes shift (142 nm), low toxicity and remarkable ability in cellular imaging. Moreover, owing to the introduction of 3,3'-dithiodipropionic acid with disulfide bond, the resultant AIE-active poly(PEG-TPE-DTDPA) could display reduction-responsiveness and be utilized for synthesis of photothermal agents in-situ. Therefore, the AIE-active poly(PEG-TPE-DTDPA) could be promising for controlled intracellular delivery of biological activity molecules and fabrication of multifunctional AIE-active materials. Therefore, these novel AIE-active polymeric nanoparticles could be of great potential for various biomedical applications, such as biological imaging, stimuli-responsive drug delivery and theranostic applications.
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http://dx.doi.org/10.1016/j.msec.2020.111437DOI Listing
January 2021

Cold Rolling Deformation Characteristic of a Biomedical Beta Type Ti-25Nb-3Zr-2Sn-3Mo Alloy Plate and Its Influence on α Precipitated Phases and Room Temperature Mechanical Properties During Aging Treatment.

Front Bioeng Biotechnol 2020 19;8:598529. Epub 2020 Oct 19.

Institute of Advanced Wear and Corrosion Resistant and Functional Materials, Jinan University, Guangzhou, China.

The microstructure characteristics and texture evolution of a biomedical metastable beta Ti-25Nb-3Zr-2Sn-3Mo (TLM; wt%) titanium alloy plate cold rolled at various reductions were studied in this article. <110> texture was easily formed in the TLM alloy plates, and a large number of dislocation tangles were generated in the β matrix in the process of cold rolling deformation. The dislocation lines, dislocation cells, subgrain boundaries, and other crystal defects introduced during cold rolling had a great impact on the morphological characteristics and volume fraction of precipitated phases during aging. These typical crystal defects could be considered as the major triggers of the formation of second phases, and they could also shorten the time of β→α phase transformation. α precipitated phases, with a size range of 150-500 nm, were formed within the β matrix in the cold deformed 34% in conjunction with the aging specimen, resulting in the relatively high tensile strength of 931 MPa and the acceptable elongation of 6.9%. When the TLM alloy plate was cold rolled at a reduction of 60% in conjunction with aging, the maximum value of ultimate strength (1,005 MPa) was achieved, but the elongation value was relatively low owing to the formation of α precipitated phases with a large size around the subgrain boundaries. In this paper, the influence of crystal defects and subgrain boundaries on the morphology characteristics and volume fraction of α precipitated phases and mechanical properties will be discussed in detail.
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http://dx.doi.org/10.3389/fbioe.2020.598529DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7604361PMC
October 2020

COVID-19 in China: From epidemiology to treatment (Review).

Exp Ther Med 2020 Dec 15;20(6):223. Epub 2020 Oct 15.

State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Laboratory of Viral Hepatitis Research, Department of Infectious Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong 510515, P.R. China.

Coronavirus disease 2019 (COVID-19) is a newly emerging infectious disease caused by the novel coronavirus SARS-CoV-2. It first became prevalent in Wuhan, Hubei, China in December 2019. COVID-19 was initially characterized by pneumonia of unknown etiology, accompanied by fever, dry cough and fatigue. Due to its highly infectious nature it rapidly led to widespread human infection, causing 80,924 confirmed cases and 3,140 mortalities in mainland China as of March 9, 2020. The present review highlights the prevalence of COVID-19 in China, the etiology, pathology, clinical presentation, laboratory and chest imaging tests, and treatment of this disease.
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http://dx.doi.org/10.3892/etm.2020.9353DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7646693PMC
December 2020

Association Between Occlusion Type and Etiology of Acute Intracranial Large Artery Occlusion.

Front Neurol 2020 22;11:582388. Epub 2020 Oct 22.

Shantou Central Hospital, Shantou, China.

To investigate the diagnostic efficiency of truncal-type occlusion and branching-site occlusion in determining the etiology of intracranial large artery occlusion related acute ischemic stroke (AIS). Patients with intracranial large artery occlusion related AIS who received stent retriever (SR) thrombectomy from November 2014 to June 2019 were included in the study. All patients underwent angiography before SR thrombectomy, which was used to evaluate the occlusion type. Differences in the distribution of occlusion types in intracranial atherosclerosis (ICAS) and embolism were assessed, and the diagnostic indicators, including the area under the ROC curve (AUC), sensitivity, and specificity were calculated. Of the 115 AIS patients with intracranial large artery occlusion, 42 were classified as having ICAS, and 73 having an embolism. In the ICAS group, branching-site occlusion was responsible for 3 (7%) cases and truncal-type occlusion for 39 (93%) cases, while in the embolism group, branching-site occlusion was responsible for 66 (90%) cases and truncal-type occlusion for 7 (10%) cases; the difference was statistically significant (all < 0.01). The AUC for ICAS predicted by truncal-type occlusion was 0.916, with a sensitivity of 92.86%, and specificity of 90.41%. Truncal-type occlusion showed a high predictability of ICAS. Determine the etiology of intracranial large artery occlusion related AIS before SR thrombectomy may be most helpful in setting up optimal endovascular treatment strategies.
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http://dx.doi.org/10.3389/fneur.2020.582388DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7642447PMC
October 2020

Hepatitis B Virus Might Be Sensed by STING-Dependent DNA Sensors and Attenuates the Response of STING-Dependent DNA Sensing Pathway in Humans with Acute and Chronic Hepatitis B Virus Infection.

Viral Immunol 2020 12 10;33(10):642-651. Epub 2020 Nov 10.

State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Laboratory of Viral Hepatitis Research, Department of Infectious Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, China.

DNA-dependent activator of interferon regulatory factors (DAIs), interferon gamma inducible protein 16 (IFI16), DEAD-box polypeptide 41 (DDX41), DNA-dependent protein kinase (DNA-PK), meiotic recombination 11 homolog A (MRE11), and cyclic GMP-AMP synthase (cGAS) have been identified as intracellular STING-dependent DNA sensors in recent years. Studies have shown that the DNA sensor-STING-interferon (IFN)- pathway plays an important role in the defense against intracellular invasion of many DNA viruses. However, the intracellular recognition of hepatitis B virus (HBV) DNA by DNA sensors is still largely unclear. In this study, we aimed to determine whether the DNA sensor-STING pathway in peripheral blood mononuclear cells (PBMCs) can be activated by acute and chronic HBV infections in humans. We first evaluated the expression of these DNA sensors in PBMCs of acute and chronic HBV-infected patients by quantitative real-time polymerase chain reaction. We next compared the expression of the upregulated DNA sensor between monocytes and nonmonocytes to find its cellular source. Finally, by stimulation, we analyzed the IFN- response of the DNA sensor-STING pathway in PBMCs and monocytes from chronic HBV-infected patients. The results showed that IFI16, DDX41, MRE11, and the adaptor STING were upregulated in chronic HBV-infected patients, whereas only IFI16 was upregulated in acute HBV-infected patients. However, IFN- expression was not changed in PBMCs from acute and chronic HBV-infected patients. We next found IFI16 was mainly expressed in monocytes of acute and chronic hepatitis B patients. Finally, by stimulation of monocytes with VACV ds 70mer, a ligand for IFI16, we confirmed the attenuated response of the IFI16-STING pathway. Taken together, our results suggest that HBV might be sensed by DNA sensors in PBMCs of acute and chronic HBV-infected patients, and meanwhile HBV infection attenuates the response of the DNA sensor-STING pathway in PBMCs and monocytes, which may facilitate the persistence of HBV infection.
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http://dx.doi.org/10.1089/vim.2020.0096DOI Listing
December 2020

Accelerating acquisition of readout-segmented echo planar imaging with a simultaneous multi-slice (SMS) technique for diagnosing breast lesions.

Eur Radiol 2020 Nov 4. Epub 2020 Nov 4.

Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China.

Objectives: To investigate the feasibility and effectiveness of SMS rs-EPI for evaluating breast lesions.

Methods: This prospective study was approved by IRB. Ninety-six patients had 102 histopathologically verified lesions (80 malignant and 22 benign) that were evaluated. Conventional rs-EPI and SMS rs-EPI data were acquired on a 3T scanner. Mean kurtosis (MK), mean diffusion (MD), and apparent diffusion coefficient (ADC) values were quantitatively calculated for each lesion on both sequences. Images were qualitatively and quantitatively analyzed with respect to image sharpness, geometric distortion, lesion conspicuity, anatomic structure, overall image quality, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR). Student's t test, Pearson correlation, receiver operating characteristic curve, Wilcoxon rank sum test, and paired-sample t tests were used for statistical analysis.

Results: Compared to conventional rs-EPI, the acquisition time of SMS rs-EPI was markedly reduced (2:17 min vs 4:27 min). Pearson's correlations showed excellent linear relationships for each parameter between conventional rs-EPI and SMS rs-EPI (MK, r = 0.908; MD, r = 0.938; and ADC, r = 0.975; p < 0.01 for all). Furthermore, SMS rs-EPI had similar diagnostic performance compared with conventional rs-EPI. SMS rs-EPI had comparable visual image quality as conventional rs-EPI, with excellent inter-reader reliability (ICC = 0.851-0.940). No differences existed between conventional rs-EPI and SMS rs-EPI for either SNR or CNR (p > 0.05).

Conclusions: Applying the SMS technique can significantly reduce the acquisition time and produce similar diagnostic accuracy while generating comparable image quality as the conventional rs-EPI.

Key Points: • SMS rs-EPI reduces scan time from 4:27 min to 2:17 min compared with conventional rs-EPI. • SMS rs-EPI has a comparable diagnostic performance to conventional rs-EPI in the differentiation between malignant and benign breast lesions. • SMS rs-EPI demonstrates comparable image quality to conventional rs-EPI with shorter scan time.
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http://dx.doi.org/10.1007/s00330-020-07393-5DOI Listing
November 2020

Biogenesis and molecular characteristics of serum hepatitis B virus RNA.

PLoS Pathog 2020 10 20;16(10):e1008945. Epub 2020 Oct 20.

Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN, United States of America.

HBV is an enveloped DNA virus that replicates its DNA genome via reverse transcription of a pregenomic (pg) RNA intermediate in hepatocytes. Interestingly, HBV RNA can be detected in virus-like particles in chronic hepatitis B (CHB) patient serum and has been utilized as a biomarker for intrahepatic cccDNA activity in treated patients. However, the biogenesis and molecular characteristics of serum HBV RNA remain to be fully defined. In this study, we found that the encapsidated serum HBV RNA predominately consists of pgRNA, which are detergent- and ribonuclease-resistant. Through blocking HBV DNA replication without affecting pgRNA encapsidation by using the priming-defective HBV mutant Y63D or 3TC treatment, we demonstrated that the cell culture supernatant contains a large amount of pgRNA-containing nonenveloped capsids and a minor population of pgRNA-containing virions. The formation of pgRNA-virion requires both capsid assembly and viral envelope proteins, which can be inhibited by capsid assembly modulators and an envelope-knockout mutant, respectively. Furthermore, the pgRNA-virion utilizes the multivesicular body pathway for egress, in a similar way as DNA-virion morphogenesis. Northern blotting, RT-PCR, and 3' RACE assays revealed that serum/supernatant HBV pgRNA are mainly spliced and devoid of the 3'-terminal sequences. Furthermore, pgRNA-virion collected from cells treated with a reversible HBV priming inhibitor L-FMAU was unable to establish infection in HepG2-NTCP cells. In summary, serum HBV RNA is secreted in noninfectious virion-like particle as spliced and poly(A)-free pgRNA. Our study will shed light on the molecular biology of serum HBV RNA in HBV life cycle, and aid the development of serum HBV RNA as a novel biomarker for CHB diagnosis and treatment prognosis.
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http://dx.doi.org/10.1371/journal.ppat.1008945DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7575114PMC
October 2020

Hsa_circ_0084927 Regulates Cervical Cancer Advancement via Regulation of the miR-634/TPD52 Axis.

Cancer Manag Res 2020 2;12:9435-9448. Epub 2020 Oct 2.

Department of Pathology, The Third Hospital of Ji'nan, Jinan, People's Republic of China.

Background: Cervical cancer (CC) is a common gynecological tumor that affects women's health. Circular RNA hsa_circ_0084927 (hsa_circ_0084927) has been reported to be upregulated in CC. However, the role and regulatory mechanism of hsa_circ_0084927 in CC are unclear.

Methods: Expression of hsa_circ_0084927, microRNA (miR)-634, and tumor protein D52 (TPD52) mRNA in CC tissues and cells was examined by quantitative real-time polymerase chain reaction (qRT-PCR). The proliferation, colony formation, cell cycle progression, apoptosis, migration, and invasion of CC cells were determined with cell counting kit-8 (CCK-8), plate clone, flow cytometry, or transwell assays. The levels of cyclin D1, cleaved-caspase-3 (c-caspase 3), matrix metalloproteinase (MMP)-2, MMP-9, and TPD52 protein were evaluated with Western blotting. The targeting relationship between hsa_circ_0084927 or TPD52 and miR-634 was verified via dual-luciferase reporter and/or RNA immunoprecipitation (RIP) assays. Xenograft assay was conducted to confirm the role of hsa_circ_0084927 in vivo.

Results: Hsa_circ_0084927 and TPD52 were upregulated while miR-634 was downregulated in CC tissues and cells. Hsa_circ_0084927 silencing reduced tumor growth in vivo and induced cell cycle arrest, apoptosis, and curbed proliferation, colony formation, migration, and invasion of CC cells in vitro. Hsa_circ_0084927 regulated TPD52 expression through sponging miR-634. MiR-634 inhibitor reversed hsa_circ_0084927 knockdown-mediated impact on the malignancy of CC cells. TPD52 elevation abolished the repressive influence of miR-634 mimics on the malignancy of CC cells.

Conclusion: Hsa_circ_0084927 accelerated CC advancement via upregulating TPD52 via sponging miR-634, offering a new evidence to support hsa_circ_0084927 as a promising target for CC treatment.
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http://dx.doi.org/10.2147/CMAR.S272478DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7537997PMC
October 2020

A Deep Learning Aided Drowning Diagnosis for Forensic Investigations using Post-Mortem Lung CT Images.

Annu Int Conf IEEE Eng Med Biol Soc 2020 07;2020:1262-1265

Feasibility of computer-aided diagnosis (CAD) systems has been demonstrated in the field of medical image diagnosis. Especially, deep learning based CAD systems showed high performance thanks to its capability of image recognition. However, there is no CAD system developed for post-mortem imaging diagnosis and thus it is still unclear if the CAD system is effective for this purpose. Particulally, the drowning diagnosis is one of the most difficult tasks in the field of forensic medicine because findings of the post-mortem image diagnosis are not specific. To address this issue, we develop a CAD system consisting of a deep convolution neural network (DCNN) to classify post-mortem lung computed tomography (CT) images into two categories of drowning and non-drowning cases. The DCNN was trained by means of transfer learning and performance evaluation was conducted by 10-fold cross validation using 140 drowning cases and 140 non-drowning cases of the CT images. The area under the receiver operating characteristic curve (AUC-ROC) for the DCNN was achieved 0.88 in average. This high performance clearly demonstrated that the proposed DCNN based CAD system has a potential for post-mortem image diagnosis of drowning.
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http://dx.doi.org/10.1109/EMBC44109.2020.9175731DOI Listing
July 2020

Strengthening of a Near β-Ti Alloy through β Grain Refinement and Stress-Induced α Precipitation.

Materials (Basel) 2020 Sep 24;13(19). Epub 2020 Sep 24.

State Key Laboratory of Powder Metallurgy, Central South University, Lu Mountain South Road, Changsha 410083, China.

Near β-Ti alloys with high strength and good ductility are desirable for application in aviation and aerospace industries. Nevertheless, strength and ductility are usually mutually exclusive in structural materials. Here we report a new thermo-mechanical process, that is, the alloy was cross-rolled in β field then aged at 600 °C for 1 h. By such a process, a high strength (ultimate tensile strength: 1480 MPa) and acceptable ductility (elongation: 10%) can be simultaneously achieved in the near β-Ti alloy, based on the microscale β matrix and nanoscale α phase. The microstructure evolution, mechanical properties and strengthening mechanisms have been clarified by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results showed that the grain size of the β phase progressively decreased with the increasing of rolling reduction. Moreover, dense dislocation structures and martensite phases distributed in the cross-rolled β matrix can effectively promote the precipitation of nanoscale α particles. TEM analyses confirmed that a heat-treatment twin was generated in the newly formed α lath during aging. These findings provide insights towards developing Ti alloys with optimized mechanical properties.
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http://dx.doi.org/10.3390/ma13194255DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7579020PMC
September 2020

The Role of the Bacterial Community in Producing a Peculiar Smell in Chinese Fermented Sour Soup.

Microorganisms 2020 Aug 21;8(9). Epub 2020 Aug 21.

Guangdong Provincial Key Laboratory of Nutraceuticals and Functional Foods, College of Food Science, South China Agricultural University, Guangzhou 510642, China.

In this paper, the volatile flavour constituents and the bacterial diversity in characteristic Chinese fermented sour soup were analysed, and the dynamics of bacteria associated with the odour were characterized. The bacterial diversity of sour soup was studied by high-throughput sequencing. A total of 10 phyla and 89 genera were detected. Firmicutes was the dominant phylum of sour soup, accounting for 87.14-98.57%. The genus structure of normal sour soup was relatively simple, and (78.05-90.26%) was the dominant genus. In addition to Lactobacillus, the foul-smelling sour soup contained more spp., spp., and spp. (relative abundance >1%) than the normal sour soup. A total of 51 aroma compounds were detected by gas chromatography-mass spectrometry(GC-IMS), including 25 esters, 8 terpenes, 8 alcohols, 3 sulfur compounds, 2 acids, 2 ketones, 1 pyrazine, 1 monoterpene and 1 aldehyde. According to the relative odour active value (ROAV) calculation, 51 important flavour-contributing substances and 7 flavour-coordinating substances were determined. The esters with the highest relative percentages and ROAV values provided the pleasant flavour of the sour soup. In the foul-smelling sour soup, the ROAV values of 1,8-cineole, isobutyl acetate, ethyl butanoate, ethyl octanoate-M, and ethyl hexanoate-M decreased, while those of diallyl disulfide-M and diallyl disulfide-D, which were probably responsible for the foul flavour, increased. Through Pearson correlation analysis, the odour production of the foul-smelling soup was determined to be related to spp., spp., spp., spp., spp., spp., spp. and spp.
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http://dx.doi.org/10.3390/microorganisms8091270DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7570168PMC
August 2020

2-Methoxy-1,4-naphthoquinone Induces Metabolic Shifts in Revealed by High-Dimensional Biological Data.

J Agric Food Chem 2020 Sep 26;68(36):9697-9706. Epub 2020 Aug 26.

Guangdong Provincial Key Laboratory of Food Quality and Safety, College of Food Science, South China Agricultural University, Guangzhou 510642, China.

is the primary pathogen causing the green mold of citrus. The need for the development of higher effective and lower toxic natural antifungal agents is urgent, owing to the lack of antifungal agents that can successfully combat . Herein, the effects and mechanisms of 2-methoxy-1,4-naphthoquinone (MNQ) as a potential inhibitor of were studied. First, MNQ showed a significant anti- effect with a minimum inhibitory concentration value of 5.0 μg/mL. Then, transcriptome, proteome, and metabolome profiling were performed on the MNQ-treated . A total of 910 genes, 297 proteins, and 174 metabolites changed significantly. The omics analysis indicated that it could be seen that MNQ mainly inhibits the growth of by affecting the synthesis of branched-chain amino acids and cell walls. These findings will be a great contribution to the further understanding of the possible molecular action of MNQ.
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http://dx.doi.org/10.1021/acs.jafc.0c03396DOI Listing
September 2020

New insights into toxic effects of arsenate on four Microcystis species under different phosphorus regimes.

Environ Sci Pollut Res Int 2020 Dec 8;27(35):44460-44469. Epub 2020 Aug 8.

Center of Environmental Emergency Response and Accident Investigation of Jiangsu Province, Nanjing, 210036, China.

Very little information is available on the stressed growth of Microcystis imposed by arsenate (As(V)) under different phosphorus (P) regimes. In this study, we examined the growth characteristics and arsenic transformation of four Microcystis species exposed under As(V) with two P sources involving dissolved inorganic phosphorus (IP) and organophosphate (D-glucose-6-phosphate disodium salt, GP). Results showed that all the four chosen Microcystis species could grow and reproduce with GP as the only P source, and the difference was insignificant when compared with IP. From optical density (OD), chlorophyll a (Chla), and actual quantum yield (Yield), the tolerance to As(V) of the chosen species was following as FACHB 905 > FACHB 1028 > FACHB 1334 > FACHB 912. Specifically, the 96 h EC of As(V) for FACHB 905 in IP was approx. 4 orders of magnitude higher than that in GP, but for other three algal species, the 96 h EC values were similar under the two given different P conditions. Furthermore, all antioxidant enzyme activities of superoxide dismutase (SOD), peroxide dismutase (POD), glutathione S-transferases (GSTs), and metalloproteinase (MTs) in algal cells were significantly increased in GP conditions. Moreover, the enzyme activities of AKP, GSTs, and MTs were inhibited with increasing As(V) levels under both IP and GP conditions. In addition, arsenite (As(III)) and methylated As of monomethylarsonic acid (MMA) and dimethylthioarsinic acid (DMA) were found in FACHB 912 and FACHB 1334 media, indicating that these Microcystis could detoxify As(V) by As biotransformation under IP and GP conditions. Specifically, As(V) reduction was elevated in media of FACHB 1334 and FACHB 905, but was decreased in media of FACHB 912 under GP conditions. Our results highlight the different P sources that impact the toxic effects of arsenate exposure on Microcystis and subsequent As biotransformation.
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http://dx.doi.org/10.1007/s11356-020-10396-wDOI Listing
December 2020

Study on Grain Refinement Mechanisms and Mechanical Properties of bi-Modal Ti-55511 Titanium Alloy during Hot Rolling.

Materials (Basel) 2020 Jul 28;13(15). Epub 2020 Jul 28.

State Key Laboratory of Powder Metallurgy, Central South University, Lu Mountain South Road, Changsha 410083, China.

Multi-pass hot rolling was performed on bi-modal Ti-55511 alloy with 50% rolling reduction at 700 °C. Mechanical properties were evaluated by tensile test, and microstructure evolution was characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that the Ti-55511 alloy with bi-modal microstructure exhibits good strength and high ductility (1102 MPa, 21.7%). Comparatively, after 50% hot rolling, an enhanced strength and decreased ductility were obtained. The refinement of α phases leads to the increased tensile strength, while the fragmentation of the equiaxed α phase results in a decreased ductility. The fragmentation process of equiaxed α phases followed the sequence of: elongation of α phases → formation of grooves and localized shear bands → the final fragmentation accomplished via deepening grooves.
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http://dx.doi.org/10.3390/ma13153351DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7435951PMC
July 2020

Effects of woody forages on biodiversity and bioactivity of aerobic culturable gut bacteria of tilapia (Oreochromis niloticus).

PLoS One 2020 2;15(7):e0235560. Epub 2020 Jul 2.

Joint Laboratory of Guangdong Province and Hong Kong Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, China.

The present study investigated the effects of four woody forages (Moringa oleifera Lam (MOL), fermented MOL, Folium mori (FM) and fermented FM) on biodiversity and bioactivity of aerobic culturable gut bacteria of tilapia (Oreochromis niloticus) by a traditional culture-dependent method. A total of 133 aerobic culturable isolates were recovered and identified from the gut of tilapia, belonging to 35 species of 12 genera in three bacterial phyla (Firmicutes, Actinobacteria and Proteobacteria). Among them, 6 bacterial isolates of Bacillus baekryungensis, Bacillus marisflavi, Bacillus pumilus, Bacillus methylotrophicus, Proteus mirabilis and Pseudomonas taiwanensis were isolated from all the five experimental groups. The Bray-Curtis analysis showed that the bacterial communities among the five groups displayed obvious differences. In addition, this result of bioactivity showed that approximate 43% of the aerobic culturable gut bacteria of tilapia displayed a distinct anti-bacterial activity against at least one of four fish pathogens Streptococcus agalactiae, Streptococcus iniae, Micrococcus luteus and Vibrio parahemolyticus. Furthermore, Bacillus amyloliquefaciens and Streptomyces rutgersensis displayed strong activity against all four indicator bacteria. These results contribute to our understanding of the intestinal bacterial diversity of tilapia when fed with woody forages and how certain antimicrobial bacteria flourished under such diets. This can aid in the further exploitation of new diets and probiotic sources in aquaculture.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0235560PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7332033PMC
September 2020

Serum Hepatitis B Virus RNA Levels Predict HBeAg Seroconversion and Virological Response in Chronic Hepatitis B Patients with High Viral Load Treated with Nucleos(t)ide Analog.

Infect Drug Resist 2020 22;13:1881-1888. Epub 2020 Jun 22.

State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Laboratory of Viral Hepatitis Research, Department of Infectious Diseases, Nanfang Hospital, Southern Medical University, Guangzhou, People's Republic of China.

Background And Aim: Hepatitis B virus (HBV) RNA has attracted increasing attention as a novel serum marker for intrahepatic HBV replication. However, the predictive value of the serum level of HBV RNA for hepatitis B e-antigen (HBeAg) seroconversion and viral response among patients with a high viral load (HVL) is unclear. We evaluated the role of the serum level of HBV RNA as a predictor of treatment response in chronic HBV (CHB) patients with an HVL.

Patients And Methods: The study cohort was 66 HBeAg-positive CHB patients with an HVL (serum HBV DNA >1.9×10 IU/mL) at baseline from our previous prospective cohort study treated with lamivudine (LAM) and adefovir dipivoxil(ADV) (N=31) or entecavir alone (N=35) for ≤96 weeks. The serum HBV RNA level was quantified by TaqMan probe-based reverse transcription real-time quantitative polymerase chain reaction at four time points.

Results: The baseline serum HBV RNA level (in log copies/mL) in patients treated with LAM+ADV and ETV monotherapy was 8.97±1.22 and 9.15±0.92, respectively. After nucleos(t)ide analog (NA) therapy, the serum HBV RNA level decreased steadily in all patients (week 0 vs week 12, p<0.001; week 12 vs week 24, p=0.010; week 24 vs week 48, p<0.001). Fifty-three (80.3%) patients achieved a virologic response (VR), and 12 (18.2%) achieved HBeAg seroconversion after 96 weeks. Multivariate analyses revealed that the serum HBV RNA level at week 12 could predict HBeAg seroconversion (OR 3.560, 95% CI: 1.39-9.110, p=0.008) and VR (1.908, 1.115-3.265, 0.018) at 96 weeks. Analyses of receiver operating characteristic curves indicated that the serum HBV RNA level 12 weeks after NA treatment had predictive value for HBeAg seroconversion (AUC=0.847, p<0.001) and VR (AUC=0.736, p=0.011).

Conclusion: The serum level of HBV RNA at 12 weeks could predict HBeAg seroconversion and a VR during NA treatment in CHB patients with an HVL.
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http://dx.doi.org/10.2147/IDR.S252994DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7319510PMC
June 2020

Heat-Killed Lactobacillus reuteri GMNL-263 Inhibits Systemic Lupus Erythematosus-Induced Cardiomyopathy in NZB/W F1 Mice.

Probiotics Antimicrob Proteins 2021 Feb;13(1):51-59

Graduate Institute of Aging Medicine, China Medical University, Taichung, Taiwan.

It has been increasingly recognized that accelerated atherosclerosis is a major cause of morbidity and mortality in patients with systemic lupus erythematosus, a multisystem autoimmune disease. In this study, we investigated the anti-apoptotic effects of heat-killed Lactobacillus reuteri GMNL-263 on the cardiac tissue of NZB/W F1 mice. The myocardial architecture of the mice heart was observed and evaluated using different staining techniques such as hematoxylin and eosin, TUNEL assay, Masson's trichrome, and fluorescent immunohistochemistry. Additionally, the probiotics-related pathway proteins were analyzed via western blot analysis. Our results showed prevention of enlarged interstitial spaces and abnormal myocardial structures in the hearts of NZB/W F1 mice with L. reuteri GMNL-263 feeding. Significant reduction in TUNEL-positive cells, Fas death receptor-related components, and apoptosis was also detected in the cardiac tissues of the NZB/W F1 mice after L. reuteri GMNL-263 feeding compared with the control group. These findings are the first to reveal the protective effects of L. reuteri GMNL-263 against cardiac abnormalities in NZB/W F1 mice and suggest the potential clinical applications of L. reuteri GMNL-263 in the treatment of SLE-related cardiovascular diseases.
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http://dx.doi.org/10.1007/s12602-020-09668-1DOI Listing
February 2021