Publications by authors named "Xiaoxiao Li"

242 Publications

Effect of site hydrological conditions and soil aggregate sizes on the stabilization of heavy metals (Cu, Ni, Pb, Zn) by biochar.

Sci Total Environ 2021 Aug 27;802:149949. Epub 2021 Aug 27.

Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, Zhejiang Gongshang University, Hangzhou 310012, PR China; Instrumental Analysis Center of Zhejiang Gongshang University, Hangzhou 310012, PR China. Electronic address:

Biochar is a popular material that would effectively immobilize heavy metals in soil, which can greatly decrease the health risk of heavy metals. Although many previous studies have studied the immobilization of heavy metals by biochar, the influence of hydrological conditions on the immobilization effect is still not clear. This paper carried out column experiments to study the effect of fluctuating groundwater table on Cu, Ni, Pb, Zn distribution and speciation with the addition of biochar from pyrolysis of swine manure. Experimental results showed that biochar could significantly decrease the leaching toxicity of Cu and Ni by 24.4% and 44.7% respectively, while the immobilization effect of Pb and Zn was relatively insignificant. The average reduction percentage of bioavailable Cu was 14.5%, 39.5% and 33.3% in the unsaturated zone, fluctuating zone and saturated zone respectively, showing the better immobilization effect in the fluctuating zone and saturated zone. The residual fraction of heavy metals increased significantly after the addition of biochar, and the increase of residual fraction was larger in small soil aggregates. This study helped illustrate the influence of hydrological conditions and soil aggregate sizes on the stabilization effect of heavy metals by biochar, which could be used to guide the remediation process of sites contaminated by heavy metals.
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http://dx.doi.org/10.1016/j.scitotenv.2021.149949DOI Listing
August 2021

Promoting Phosphidation Process using Oxygen Vacancy Precursor for Efficient Hydrogen Evolution Reaction.

Chem Asian J 2021 Sep 10. Epub 2021 Sep 10.

Jiangxi University of Science and Technology School of Materials and Chemical Engineering, 156 Hakka Avenue, Zhanggong District, CHINA.

Based on the previous works, most of the Transition metal phosphides(TMPs) were directly prepared by decomposing NaH 2 PO 2 with the precursors at high temperatures, which resulted in different degrees of phosphidation in the final product. Therefore, it is necessary to design a wholly innovative approach to enhance the degree of phosphidation in the material using crystal defects. In this approach, oxygen-vacancy iron oxide/iron foam (Ov-Fe 2 O 3 /IF) was firstly prepared by generating oxygen vacancy in situ in iron foam through heating in vacuum conditions. Subsequently, FeP/IF was formed by phosphating Ov-Fe 2 O 3 /IF. Under the effects of oxygen vacancies, oxygen-vacancy iron oxide could be completely phosphatized to produce more active sites on the surface of the material. This, in turn, could result in a catalyst with exceptional hydrogen evolution activity. Thus, the successful fabrication of FeP demonstrated in this work provides an effective and feasible way for the preparation of other high-efficiency catalysts.
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http://dx.doi.org/10.1002/asia.202100937DOI Listing
September 2021

Occurrence of novel organophosphate esters derived from organophosphite antioxidants in an e-waste dismantling area: Associations between hand wipes and dust.

Environ Int 2021 Sep 6;157:106860. Epub 2021 Sep 6.

MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China.

Electronic waste (e-waste) is a well-known source of plastic additives in the environment. However, the e-waste-related occupational exposure to organophosphite antioxidants (OPAs) and the relevant oxidation products-novel organophosphate esters (NOPEs)-via different pathways is still unknown. In this study, six OPAs and three NOPEs were measured in 116 dust and 43 hand-wipe samples from an e-waste dismantling area in Central China. The median concentrations of ΣOPAs and ΣNOPEs were 188 and 13,900 ng·g in workshop dust and 5,250 ng·m and 53,600 ng·m on workers' hands, respectively. The increasing concentrations of dust in the form of triphenyl phosphate (TPHP) (p < 0.01) and tris(2,4-di-tert-butylphenyl) phosphate (AO168 = O) (p < 0.05) were strongly associated with the corresponding concentration on workers' hands. Furthermore, men had significantly lower levels of NOPEs on their hands than did women (p < 0.01). Moreover, the hand wipe levels of AO168 = O (41,600 ng·m) was significantly higher than that of the typical OPE (TPHP, 7370 ng·m), and the hand-to-mouth contact (ΣOPAs, 9.48 ng·kg bw·day; ΣNOPEs, 109 ng·kg bw·day) was a more significant and integrated pathway than dust ingestion (ΣOPAs, 0.10 ng·kg bw·day; ΣNOPEs, 5.01 ng·kg bw·day) of e-waste related occupational exposure to these "new" chemicals.
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http://dx.doi.org/10.1016/j.envint.2021.106860DOI Listing
September 2021

Ionic copper strengthens the toxicity of tetrabromobisphenol A (TBBPA) to denitrification by decreasing substrate transport and electron transfer.

J Hazard Mater 2021 08 27;416:126203. Epub 2021 May 27.

School of Ecology and Environment, Anhui Normal University, 189 South of Jiuhua Road, Wuhu, Anhui 241002, China.

Increasing electrical and electronic waste have raised concerns about the potential toxicity of brominated flame retardants (BFRs) and heavy metals (HMs). However, few studies have focused on the combined effect of BFRs and HMs on microorganisms, especially denitrifying bacteria, which have an essential role in N cycles and NO emission. Herein, we investigate the combined effect of tetrabromobisphenol A (TBBPA) and Cu on model denitrifying bacteria. A further 24.5% decline in N removal efficiency was observed when 0.05 mg/L Cu were added into a denitrifying system containing 0.75 mg/L TBBPA. Further study demonstrated that Cu heightened the toxicity of TBBPA to denitrification via following aspects: (1) Cu stimulated EPS secretion induced by TBBPA during denitrification, blocked the transmembrane transport of glucose, which caused insufficient carbon substrate for bacteria growth and electron provision; (2) Cu further suppressed key denitrifying enzymes' activity and down-regulated genes involving electron transport induced by TBBPA, led to the decrease of electron transport activity. Finally, the decrease of bacterial growth, insufficient electron donor, and lower electron transport activity caused the synergetic toxic effect of TBBPA and Cu on denitrification. Overall, the present study provides new insights into the combined effect of BFRs and HMs on microorganisms.
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http://dx.doi.org/10.1016/j.jhazmat.2021.126203DOI Listing
August 2021

Genome-Wide Transcription Analysis of Electroacupuncture Precondition-Induced Ischemic Tolerance on SD Rat With Ischemia-Reperfusion Injury.

Front Genet 2021 16;12:719201. Epub 2021 Aug 16.

Key Laboratory of Acupuncture and Medicine Research of Ministry of Education, Nanjing University of Chinese Medicine, Nanjing, China.

Acupuncture promotes the recovery of neurological function by the overall improvement of ischemic brain injury. It is not only regarded as a rehabilitative treatment but also a pretreatment method for stroke. However, its mechanism has not been fully elucidated. In this study, rats were treated with electroacupuncture (EA) at Baihui (GV20) for 30 min/day for 6 days, ahead of conducting cerebral ischemia-reperfusion (I/R) injury. Infarction volume, Evans blue leakage, and neurological deficits were evaluated at 24 h after I/R injury. Then, the ipsilateral ischemic brain was isolated for RNA sequencing (RNA-Seq) to identify molecular consequences. The results showed that EA pretreatment decreased blood-brain barrier (BBB) permeability, reduced brain infarction volume, and improved neurological outcomes. EA pretreatment could upregulate expression of antivirus and immunity activity-associated genes (such as , , , and ) and downregulate expression of matrix disruption-associated genes (, , , etc.) in healthy rats. In addition, it could partially reverse or ameliorate genome-wide transcription changes of the ipsilateral ischemic brain. For the first time, this study provides insight into genomic network modulation of a healthy rat with EA treatment and a EA-preconditioned rat under subsequent I/R injury, which is helpful in explaining acupuncture precondition-induced ischemic tolerance of stroke. It also provides new strategies and targets for the prevention of ischemic stroke.
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http://dx.doi.org/10.3389/fgene.2021.719201DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8415365PMC
August 2021

Genital Human Papillomavirus Prevalence and Genotyping Among Males in Putuo District of Shanghai, China 2015-2019.

Med Sci Monit 2021 Sep 3;27:e932093. Epub 2021 Sep 3.

Laboratory Medicine Department, Putuo Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China (mainland).

BACKGROUND Reports of human papillomavirus (HPV) infection and genotype distribution in Chinese men are limited, and HPV vaccination has not yet been recommended for men in China. MATERIAL AND METHODS We retrospectively reviewed the prevalence and genotyping of male genital HPV. A total of 1227 male patients (aged 17 to 81 years) attending the dermatology and sexually transmitted disease clinics at Putuo District Center Hospital in Shanghai from 2015 to 2019 were included. Genital exfoliated specimens were obtained for detection and genotyping of 27 HPV types by Luminex-based multiplex assay. RESULTS The prevalence of any HPV was 65.5% (804/1227). The rate of multiple infection was 25.8% (317/1227). The 5 main HPV types were 6 (32.0%), 11 (23.2%), 16 (5.6%), 43 (4.3%), and 59 (4.0%). Among all detected HPV genotypes, 65.5% (875/1336) were 9-valent HPV genotypes. No significant differences were observed in the detection rate of HPV infection over 5 years (P>0.05). Age groups ≤24 years (70.7%) and ≥55 years (72.9%) showed higher infection rates, and significant differences were detected in rates of low-risk HPV infection in different age-stratified groups (P<0.05). Prevalence of HPV infection among patients with warts (74.4%) was significantly higher than that of patients with other clinical characteristics (40.4%) and physical examination (63.6%). CONCLUSIONS Our study suggested that more than half of Chinese male patients have detectable HPV infections, and penis-genital and anogenital warts were the most common clinical manifestations. Moreover, the available 9-valent HPV vaccine covers the most frequently observed HPV types among men.
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http://dx.doi.org/10.12659/MSM.932093DOI Listing
September 2021

Longitudinal change in components of astigmatism and its association with axial length-corneal radius ratio in Chinese young children: the Nanjing Eye Study.

Graefes Arch Clin Exp Ophthalmol 2021 Aug 26. Epub 2021 Aug 26.

Department of Ophthalmology, The First Affiliated Hospital With Nanjing Medical University, 300 Guangzhou Road, Nanjing, 210029, China.

Purpose: To assess the longitudinal change in components of astigmatism from age 4 to 7 years and its association with axial length-corneal radius ratio (AL/CR).

Methods: Children born between September 2011 and August 2012 in Yuhuatai District of Nanjing were invited to participate in the Nanjing Eye Study for a comprehensive eye examination annually since 2015. The data presented in this paper were obtained in 2016, 2017, and 2019. At each study encounter, noncycloplegic autorefraction and ocular biometric parameters were measured. Changes of total astigmatism (TA), corneal astigmatism (CA), anterior corneal astigmatism (ACA), residual astigmatism (RA), and internal astigmatism (IA) were analyzed in clinical notation (Cyl) and vector notation (J, J).

Results: Nine hundred fifty-four children (mean ± standard deviation of baseline age: 4.63 ± 0.29 years, 53.7% boys) had complete data and were included in this study. Mean slopes of longitudinal changes in Cyl notation were significantly negative for TA, CA, and ACA, but positive for IA. TA, CA, ACA, and RA of J notation had a shift toward increasing with-the-rule (WTR) astigmatism and/or decreasing against-the-rule (ATR) astigmatism. TA of J notation showed an increase in astigmatism at axis 135° and/or a decrease in astigmatism at axis 45°, while CA and ACA of J notation showed an opposite change. Longitudinal changes in ACA and IA were negatively correlated in J notation, but not in J notation. Based on compensation factor (CF, defined as the minus ratio of IA and ACA), the compensation proportions for J in varying degrees (CF: 0.1-2) in 2016, 2017, and 2019 were 91.3%, 93.5%, and 90.0%, respectively, while these for J were 74.9%, 76.5%, and 34.6%, respectively. Higher AL/CR increase was associated with less decrease or more increase in CA and ACA of Cyl notation, and a shift toward increasing WTR and/or decreasing ATR in these of J notation.

Conclusions: The compensatory role of IA was persistent and prominent from 4 to 7 years old for J notation in Chinese young children. The progression of AL/CR was correlated with astigmatism originated from the cornea.
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http://dx.doi.org/10.1007/s00417-021-05386-8DOI Listing
August 2021

Prevalence of Self-Reported Symptoms of Computer Vision Syndrome and Associated Risk Factors among School Students in China during the COVID-19 Pandemic.

Ophthalmic Epidemiol 2021 Aug 25:1-11. Epub 2021 Aug 25.

Department of Ophthalmology, The First Affiliated Hospital with Nanjing Medical University, Nanjing, China.

Purpose: To determine the prevalence and risk factors of self-reported symptoms of Computer Vision Syndrome (CVS) in school students during COVID-19 pandemic.

Methods: In this cross-sectional study in Nanjing, China, students (grades 1-12) from six randomly selected schools self-administered the online survey questionnaire about hours on electronic devices, outdoor activities, frequency and intensity of 17 CVS symptoms during virtual learning period of COVID-19 pandemic.

Results: Among 2363 invited students, 2005 (84.8%) completed the survey. Mean (SD) age was 12 (3.0) years, 51% were male, 53% wore glasses, 56% did not know the 20-20-20 rule (take a 20 second break every 20 min of close work and gaze at objects at least 20 feet away) and 6.5% knew but never followed the 20-20-20 rule. Mean (SD) hours/day was 4.6 (3.4) for screen time and 1.2 (1.0) for outdoor activities. Total of 1543 (77.0%) students reported at least one CVS symptom (median = 4) with eye dryness and itching the most common (48%). In multivariable analysis, CVS score 4 or more was independently associated with older age (adjusted odds ratio (aOR) = 1.05 for per-year increase, = 0.02), children with myopia not wearing glasses (aOR = 2.12, = 0.0003), astigmatism (aOR = 1.37, = 0.04), other ocular diseases (aOR = 1.59, = 0.005), not complying 20-20-20 rule (aOR = 2.13, = 0.04), more screen time (aOR = 1.53 for >6 vs. ≤2 hours, = 0.0001) and less outdoor activities (aOR = 1.37 for ≤0.6 vs. ≥1.9 hours, = 0.005).

Conclusions: During COVID-19 pandemic, self-reported CVS symptoms occurred in more than three-quarters of students. Besides pre-existing ocular diseases, children with myopia not wearing glasses, excessive time on screens, non-compliance of the 20-20-20 rule and reduced outdoor activities were associated with higher risk of CVS.
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http://dx.doi.org/10.1080/09286586.2021.1963786DOI Listing
August 2021

Identification of CO induces oxidative stress to change bacterial surface properties.

Chemosphere 2021 Aug 22;277:130336. Epub 2021 Mar 22.

State Key Laboratory of Pollution Control and Resources Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, China.

The surface properties of bacteria play an essential role in their abilities to perform transmembrane communication, adherence, immobilization, flocculation, etc. However, the responsiveness of bacterial surfaces to elevated atmospheric CO remains unknown. In this study, using the model bacteria, Paracoccus denitrificans, the effect of CO on the primary bacterial surface properties, specifically hydrophobicity and surface charge, has been explored. We found that hydrophilicity and negative surface charge both rose in conjunction with increased atmospheric CO concentrations. Studies of the potential mechanisms involved have illustrated that elevated CO significantly increases the production of polysaccharides in extracellular polymeric substances (EPS). Various hydrophilic groups and negative charges in these polysaccharides prompt hydrophilicity and surface charge variations in bacteria. Further research has identified that elevations in CO result in the accumulation of reactive species, specifically reactive nitrogen species (RNS). In this study, it was found that RNS damaged the permeability of bacterial membranes by inducing lipid peroxidation and then caused the leakage of intracellular substrate, which ultimately led to an increase in EPS polysaccharides. Our findings suggest that changes in bacterial surface properties due to atmospheric CO elevation, as well as the reactions these trigger, merit widespread attention.
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http://dx.doi.org/10.1016/j.chemosphere.2021.130336DOI Listing
August 2021

Review of wheeled mobile robot collision avoidance under unknown environment.

Sci Prog 2021 Jul-Sep;104(3):368504211037771

Guangdong Key Laboratory of Modern Control Technology, Institute of Intelligent Manufacturing, Guangdong Academy of Sciences, Guangzhou, Guangdong, P.R. China.

Recently, the working scenes of the robot have been emerging as diversity and complexity with gradually mature of robotic control technology. The challenge of robot adaptability emerges, especially in complicated and unknown environments. Among the numerous researches on improving the adaptability of robots, aiming at avoiding collision between robot and external environment, obstacle avoidance has drawn much attention. Compared to the global circumvention requiring the environmental information that is known, the local obstacle avoidance is a promising method due to the environment is possibly dynamic and unknown. This study is aimed at making a review of research progress about local obstacle avoidance methods for wheeled mobile robots (WMRs) under complex unknown environment in the last 20 years. Sensor-based obstacle perception and identification is first introduced. Then, obstacle avoidance methods related to WMRs' motion control are reviewed, mainly including artificial potential field (APF)-based, population-involved meta heuristic-based, artificial neural network (ANN)-based, fuzzy logic (FL)-based and quadratic optimization-based, etc. Next, the relevant research on Unmanned Ground Vehicles (UGVs) is surveyed. Finally, conclusion and prospection are given. Appropriate obstacle avoidance methods should be chosen based on the specific requirements or criterion. For the moment, effective fusion of multiple obstacle avoidance methods is becoming a promising method.
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http://dx.doi.org/10.1177/00368504211037771DOI Listing
August 2021

Acid-Base Clusters during Atmospheric New Particle Formation in Urban Beijing.

Environ Sci Technol 2021 Aug 2. Epub 2021 Aug 2.

State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.

Molecular clustering is the initial step of atmospheric new particle formation (NPF) that generates numerous secondary particles. Using two online mass spectrometers with and without a chemical ionization inlet, we characterized the neutral clusters and the naturally charged ion clusters during NPF periods in urban Beijing. In ion clusters, we observed pure sulfuric acid (SA) clusters, SA-amine clusters, SA-ammonia (NH) clusters, and SA-amine-NH clusters. However, only SA clusters and SA-amine clusters were observed in the neutral form. Meanwhile, oxygenated organic molecule (OOM) clusters charged by a nitrate ion and a bisulfate ion were observed in ion clusters. Acid-base clusters correlate well with the occurrence of sub-3 nm particles, whereas OOM clusters do not. Moreover, with the increasing cluster size, amine fractions in ion acid-base clusters decrease, while NH fractions increase. This variation results from the reduced stability differences between SA-amine clusters and SA-NH clusters, which is supported by both quantum chemistry calculations and chamber experiments. The lower average number of dimethylamine (DMA) molecules in atmospheric ion clusters than the saturated value from controlled SA-DMA nucleation experiments suggests that there is insufficient DMA in urban Beijing to fully stabilize large SA clusters, and therefore, other basic molecules such as NH play an important role.
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http://dx.doi.org/10.1021/acs.est.1c02701DOI Listing
August 2021

Identification of Hub Genes and Small Molecule Drugs Associated with Acquired Resistance to Gefitinib in Non-Small Cell Lung Cancer.

J Cancer 2021 2;12(17):5286-5295. Epub 2021 Jul 2.

Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, China.

Targeting EGFR, epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs), brings lights to the treatment of non-small cell lung cancer (NSCLC). Although T790M mutation responded as one of the main reasons of acquired resistance, still 15% of the resistance patients can't be explained by the known mechanisms. The purpose of this research was to identify some new mechanisms of gefitinib acquired resistance, and to predict small molecules drugs which may reverse drug resistance by integrated bioinformatics analysis. The GSE34228 data package containing the microarray data of acquired gefitinib-resistant cell line (PC9GR) and gefitinib-sensitive cell line (PC9) from the GEO database were downloaded, and gene co-expression networks by weighted gene co-expression network analysis (WGCNA) were constructed to identified key modules and key genes related to gefitinib resistance. Furthermore, the significantly differentially expressed genes (DEGs) between the two cell types were screened out, and a protein-protein interaction (PPI) network to obtain the key genes of DEGs was accordingly constructed. Through the above two methods, 4 hub genes, PI3, S100A8, AXL and PNPLA4 were mined as the most relevant to gefitinib resistance. Among them, PI3, S100A8 were down-regulated in PC9GR cell samples, while AXL, PNPLA4 were up-regulated. The gene set enrichment analysis (GSEA) for single gene showed that the four hub genes were mainly correlated with cell proliferation and cycle. Besides, small molecule drugs with the potential to overcome resistance, such as Emetine and cephaeline, were screened by CMap database. Consistent with this, experiments results have shown that emetine and cephaeline can increase the sensitivity of drug-resistant cells to gefitinib, and the mechanism may be related to the regulation of PI3 and S100A8. In conclusion, 4 hub genes were found to be related to the occurrence of gefitinib resistance in non-small cell lung cancer, and several small molecule drugs were screened out as potential therapeutic agents to overcome gefitinib resistance, which may lead a new way for the treatment of NSCLC of acquired resistance to gefitinib.
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http://dx.doi.org/10.7150/jca.56506DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8317531PMC
July 2021

Recognition Characteristics of Facial and Bodily Expressions: Evidence From ERPs.

Authors:
Xiaoxiao Li

Front Psychol 2021 5;12:680959. Epub 2021 Jul 5.

Academy of Psychology and Behavior, Tianjin Normal University, Tianjin, China.

In the natural environment, facial and bodily expressions influence each other. Previous research has shown that bodily expressions significantly influence the perception of facial expressions. However, little is known about the cognitive processing of facial and bodily emotional expressions and its temporal characteristics. Therefore, this study presented facial and bodily expressions, both separately and together, to examine the electrophysiological mechanism of emotional recognition using event-related potential (ERP). Participants assessed the emotions of facial and bodily expressions that varied by valence (positive/negative) and consistency (matching/non-matching emotions). The results showed that bodily expressions induced a more positive P1 component and a shortened latency, whereas facial expressions triggered a more negative N170 and prolonged latency. Among N2 and P3, N2 was more sensitive to inconsistent emotional information and P3 was more sensitive to consistent emotional information. The cognitive processing of facial and bodily expressions had distinctive integrating features, with the interaction occurring in the early stage (N170). The results of the study highlight the importance of facial and bodily expressions in the cognitive processing of emotion recognition.
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http://dx.doi.org/10.3389/fpsyg.2021.680959DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8287205PMC
July 2021

Plant Polysaccharide Modulate Biofilm Formation and Insecticidal Activities of Strains.

Front Microbiol 2021 28;12:676146. Epub 2021 Jun 28.

State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops & Key Laboratory of Biopesticide and Chemical Biology of Ministry of Education & Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops, College of Life Sciences & College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China.

After the biological pesticide (Bt) is applied to the field, it has to remain on the surface of plants to have the insecticidal activities against insect pests. Bt can form biofilms on the surface of vegetable leaves, which were rich in polysaccharides. However, the relationship between polysaccharides of the leaves and the biofilm formation as well as the insecticidal activities of Bt is still unknown. Herein, this study focused on the effects of plant polysaccharides pectin and xylan on biofilm formation and the insecticidal activities of Bt strains. By adding pectin, there were 88 Bt strains with strong biofilm formation, 69 strains with weak biofilm formation, and 13 strains without biofilm formation. When xylan was added, 13 Bt strains formed strong biofilms, 98 strains formed weak biofilms, and 59 strains did not form biofilms. This indicated that two plant polysaccharides, especially pectin, modulate the biofilm formation of Bt strains. The ability of pectin to induce biofilm formation was not related to Bt serotypes. Pectin promoted the biofilms formed by Bt cells in the logarithmic growth phase and lysis phase at the air-liquid interface, while it inhibited the biofilms formed by Bt cells in the sporangial phase at the air-liquid interface. The dosage of pectin was positively correlated with the yield of biofilms formed by Bt cells in the logarithmic growth phase or lysis phase at the solid-liquid interfaces. Pectin did not change the free-living growth and the cell motility of Bt strains. Pectin can improve the biocontrol activities of the spore-insecticidal crystal protein mixture of Bt and BtK commercial insecticides, as well as the biofilms formed by the logarithmic growth phase or lysis phase of Bt cells. Our findings confirmed that plant polysaccharides modulate biofilm formation and insecticidal activities of Bt strains and built a foundation for the construction of biofilm-type Bt biopesticides.
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http://dx.doi.org/10.3389/fmicb.2021.676146DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8273441PMC
June 2021

Efficacy and safety of tramadol for knee or hip osteoarthritis: a systematic review and network meta-analysis of randomized controlled trials.

Arthritis Care Res (Hoboken) 2021 Jul 12. Epub 2021 Jul 12.

Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, Hunan, China.

Objective: To examine efficacy and safety of tramadol for knee or hip osteoarthritis (OA).

Methods: Pubmed, Embase, Cochrane Library and Web of Science were searched up to May 2020 for randomized controlled trials (RCTs) comparing any of the following interventions: tramadol 100 mg/day, 200 mg/day and 300 mg/day, and placebo for knee or hip OA. Pain and function were measured at or nearest to twelve weeks for efficacy. Gastrointestinal, cardiovascular and central nervous system (CNS) adverse effects (AEs), and withdrawals were measured for safety. Bayesian network meta-analysis was conducted.

Results: Six RCTs (3,611 participants) were included. Tramadol 100 mg/day (standardized mean difference [SMD]=-0.16, 95% confidence interval [CI]: -0.34 to 0.00), 200 mg/day (SMD=-0.21, 95%CI: -0.37 to -0.06) and 300 mg/day (SMD=-0.30, 95%CI: -0.48 to -0.14) were statistically more effective than placebo in pain relief, but only tramadol 300 mg/day was better than placebo in functional improvement (SMD=-0.24, 95%CI: -0.47 to -0.03). Tramadol 100 mg/day (relative risk [RR]=2.29, 95% credible interval [CrI]: 1.22 to 4.25), 200 mg/day (RR=4.35, 95%CrI: 2.31 to 8.01) and 300 mg/day (RR=6.02, 95%CrI: 3.22 to 11.1) involved a higher risk of gastrointestinal AEs. Similarly, tramadol 100-300 mg/day showed a higher risk of CNS AEs and withdrawals. However, the risk of cardiovascular AEs remained unclear.

Conclusions: Only tramadol 300mg/day showed minimal improvement in pain and function but with increasing AEs compared with placebo. Tramadol may not be sufficiently recommended for knee or hip OA by presented evidence, especially in patients with the risk of gastrointestinal and CNS AEs.
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http://dx.doi.org/10.1002/acr.24750DOI Listing
July 2021

Establishment of an effective nursing team against COVID-19-a COVID-19 treatment center experience.

Ann Palliat Med 2021 Jun;10(6):6661-6668

Department of Thoracic Surgery, The First Hospital of China Medical University, Shenyang, China.

Background: Novel coronavirus disease 2019 (COVID-19) is a serious infectious respiratory disease widespread worldwide. Nurses are the front-line staff in contact with infected patients and play a key role in treating patients and controlling the epidemic. The purpose of this study was to share our nursing team's experience in the treatment of COVID-19 and provide clinical guidance.

Methods: Detail nursing system arrangement was laid down: (I) reasonable division of ward channel was built; (II) effectively arranged human nursing resources and establishing special groups, including Training group, Critical patients nursing group, Quality control group, Epidemic preventive measures group, and Logistics support group; (III) optimize nursing workflow and establish various rules and regulations; (IV) scientific scheduling and humanized management; (V) pay attention to psychological support and adopt humanized management. The pre-job preparation, treatment results, and medical staff infection number were recorded.

Results: Fifty-four intensive care nurses all passed the training with an average score of 99.75±0.13. One patient was dead, and 22 patients were discharged smoothly. The average length of stay was 9.12 days. The medical staff was not infected.

Conclusions: The treatment center was set up and functioning rapidly, safely, and orderly by implementing an emergency management strategy. The goal of a high rescue rate, low mortality, and no medical staff infection was achieved. This nursing system could be applied in COVID-19 patient treatment.
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http://dx.doi.org/10.21037/apm-21-1255DOI Listing
June 2021

Hydrogen Sulfide Contributes to Uterine Quiescence Through Inhibition of NLRP3 Inflammasome Activation by Suppressing the TLR4/NF-κB Signalling Pathway.

J Inflamm Res 2021 25;14:2753-2768. Epub 2021 Jun 25.

Department of Laboratory Medicine, Putuo Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, People's Republic of China.

Background: The NLRP3 inflammasome plays a critical role in inflammatory responses in various diseases. Our previous study showed that NLRP3 expression was significantly increased in human pregnancy tissue during term labour. Therefore, we explored whether NLRP3 participated in inflammatory responses of preterm and term labour and whether this process could be relieved by HS, one anti-inflammatory gasotransmitter.

Methods: Human myometrium was obtained from non-labouring and labouring women. Mouse myometrium was obtained from LPS-induced infectious preterm labour. Uterine smooth muscle cells were isolated from non-labouring women's myometrial tissues, transfected with siRNA, and treated cells with IL-1β, HS donor NaHS, NF-κB inhibitor BAY 11-7082 and TLR4 inhibitorTAK-242. The NLRP3 inflammasome, CSE, CBS, TLR4, uterine contraction-associated proteins (CAPs), NF-κB activation and inflammatory cytokine expression were assessed by Western blotting and RT-PCR.

Results: The NLRP3 inflammasome, TLR4 and activated NF-κB expression were upregulated in human term labour, mouse preterm labour and human uterine smooth muscle cells treated with IL-1β. NLRP3 levels were negatively correlated with CSE and CBS expression. Treatment with the HS donor NaHS delayed LPS-induced preterm birth in mice and inhibited NLRP3 inflammasome activation. In siNLRP3-transfected cells, there was a significant decrease in the expression of CAPs and inflammatory cytokines compared with IL-1β stimulation. In addition, treatment with the HS donor NaHS inhibited NLRP3 inflammasome activation, reduced the expression of uterine contraction-associated proteins and inflammatory cytokines and reduced the activation of TLR4 and NF-κB compared with stimulation with IL-1β in human uterine smooth muscle cells. Furthermore, treatment of uterine smooth muscle cells with BAY 11-7082 and TAK-242 found that NLRP3 activation was regulated by the TLR4 and NF-κB pathways.

Conclusion: HS suppresses CAP expression and the inflammatory response and contributes to uterine quiescence by inhibiting the TLR4/NF-κB signalling pathway and downstream NLRP3 inflammasome activation. Thus, HS contributes to uterine quiescence through inhibition of NLRP3 inflammasome activation by suppressing the TLR4/NF-κB signalling pathway.
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http://dx.doi.org/10.2147/JIR.S308558DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8242154PMC
June 2021

Parents' experiences on the combined use of continuous subcutaneous insulin infusion and real-time continuous glucose monitoring to manage Type 1 diabetes in their children: A systematic review and meta-synthesis of qualitative studies.

Nurs Open 2021 Jun 30. Epub 2021 Jun 30.

Jinan University, Guangzhou, China.

Aim: To explore the experiences and perspectives of the combined use of continuous subcutaneous insulin infusion (CSII) and continuous glucose monitoring (CGM) on parents of children with TIDM on their daily life.

Design: A systematic review and meta-synthesis of qualitative studies.

Methods: A systematic literature search of English studies published in seven databases between 2006-2021: CINAHL, MEDLINE, EMBASE, PubMed, PsycINFO, Cochrane Library and Scopus. All included studies underwent the process of thematic interpretive integration by the author team.

Results: Nine studies met the inclusion criteria. Six derived themes were generated which contained interacting with devices, interacting with glycaemic information, improving quality of life for parents of children with T1DM, burden of living with CSII therapy and CGM, impact on the parent-child relationship, requirement and expectation to advanced diabetes technology. Advanced diabetes technologies affect physical, emotional and relationship between the daily life of parents and their children with T1DM.
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http://dx.doi.org/10.1002/nop2.971DOI Listing
June 2021

Effects and safety of acne vulgaris with external application of herbal medicines: A protocol for systematic review and meta analysis.

Medicine (Baltimore) 2021 Jul;100(26):e26408

Department of Nursing, The First People's Hospital of Foshan.

Background: Acne vulgaris (AV) is a common dermatologic disease. The morbidity is increasing annually. External application of herbal medicines (EAHM) has been pervasively used in the therapy of AV. EAHM , as the traditional Chinese therapy, is widely applied in clinical trials for AV. The aim of this review is to systematically evaluate the efficacy and safety of EAHM in the therapy for AV.

Methods: We will conduct an electronic search of 13 databases from their inception to May, 2020, including PubMed, EMBASE, MEDLINE, Web of Science, Cochrane Library, SpringerLink, WHO International Clinical Trials Registry Platform, Wanfang China database, China National Knowledge Infrastructure, Chinese Biomedical Literature Database, Chinese Scientific Journal Database, as well as China's Conference Papers Database and China Dissertation database. Other valid search strategies will also be retrieved to complete this review. All randomized controlled trials in which EAHM was used for the treatment of AV will be adopted. Two researchers will select eligible studies respectively according to a predefined protocol. Methodological quality will be assessed with Cochrane risk of bias by means of RevMan V.5.3.5 software.

Results: This systematic view will present a high-quality synthesis based on current evidence of EAHM intervention for AV patients.

Conclusion: The summary of our systematic view will provide evidence to judge whether EAHM is an effective and safe intervention for AV patients.
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http://dx.doi.org/10.1097/MD.0000000000026408DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8257869PMC
July 2021

3,3'-Diindolylmethane Enhances Paclitaxel Sensitivity by Suppressing DNMT1-Mediated KLF4 Methylation in Breast Cancer.

Front Oncol 2021 3;11:627856. Epub 2021 Jun 3.

Laboratory Medicine, Putuo Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China.

Paclitaxel (PTX) is a first-line chemotherapeutic drug for the treatment of breast cancer, but drug resistance seriously limits its clinical use. The aim of the present work was to explore the effect of 3,3'-diindolylmethane (DIM) on PTX sensitivity and its possible mechanism in breast cancer. The expression of Krüppel-like factor 4 (KLF4) and DNA-methyltransferase 1 (DNMT1) in breast cancer tissues were assessed by immunohistochemistry and Western blotting. The methylation of was evaluated by the MassARRAY platform. The lentivirus carrying and gene or shRNA targeting DNMT1 were used to overexpress KLF4 or knockdown DNMT1 in MCF-7 and T47D breast cancer cells and the role of KLF4 and DNMT1 in regulation of PTX sensitivity was investigated. The effect of PTX on inhibiting the proliferation of MCF-7 and T47D cells was measured by CCK-8 assay. Flow cytometry was used to examine cell apoptosis. The expression of mRNA and protein was evaluated by qRT-PCR and Western blotting analysis, respectively. Our data showed that the expression of DNMT1 was increased, and the methylation level of CpG sites (-148 bp) in the promoter was increased while the KLF4 expression was significantly decreased in breast cancer tissues. Overexpression of KLF4 increased the sensitivity of MCF-7 and T47D cells to PTX. DNMT1 increased the methylation of the KLF4 promoter and decrease the expression of KLF4. Knockdown of DNMT1 increased the sensitivity of MCF-7 and T47D cells to PTX. DIM enhanced the PTX sensitivity of MCF-7 and T47D cells, decreased the expression of DNMT1 and the methylation level of KLF4 promoter, thus increasing the level of KLF4. Furthermore, overexpression of DNMT1 attenuated the effect of DIM on the regulation of PTX sensitivity. Collectively, our data indicated that DNMT1-mediated hypermethylation of promoter leads to downregulation of KLF4 in breast cancer. The level of KLF4 is correlated with the sensitivity of MCF-7 and T47D cells to PTX. DIM could enhance the antitumor efficacy of PTX on MCF-7 and T47D cells by regulating DNMT1 and KLF4.
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http://dx.doi.org/10.3389/fonc.2021.627856DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8209418PMC
June 2021

Acetylation of the CspA family protein CspC controls the type III secretion system through translational regulation of exsA in Pseudomonas aeruginosa.

Nucleic Acids Res 2021 07;49(12):6756-6770

State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, China.

The ability to fine tune global gene expression in response to host environment is critical for the virulence of pathogenic bacteria. The host temperature is exploited by the bacteria as a cue for triggering virulence gene expression. However, little is known about the mechanism employed by Pseudomonas aeruginosa to response to host body temperature. CspA family proteins are RNA chaperones that modulate gene expression. Here we explored the functions of P. aeruginosa CspA family proteins and found that CspC (PA0456) controls the bacterial virulence. Combining transcriptomic analyses, RNA-immunoprecipitation and high-throughput sequencing (RIP-Seq), we demonstrated that CspC represses the type III secretion system (T3SS) by binding to the 5' untranslated region of the mRNA of exsA, which encodes the T3SS master regulatory protein. We further demonstrated that acetylation at K41 of the CspC reduces its affinity to nucleic acids. Shifting the culture temperature from 25°C to 37°C or infection of mouse lung increased the CspC acetylation, which derepressed the expression of the T3SS genes, resulting in elevated virulence. Overall, our results identified the regulatory targets of CspC and revealed a regulatory mechanism of the T3SS in response to temperature shift and host in vivo environment.
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http://dx.doi.org/10.1093/nar/gkab506DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8266623PMC
July 2021

Association between oral microflora and gastrointestinal tumors (Review).

Oncol Rep 2021 Aug 16;46(2). Epub 2021 Jun 16.

State Key Laboratory of Genetic Engineering and Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai 200438, P.R. China.

The oral cavity contains the highest density and the most species of microorganisms compared with other parts of the body. Recent studies have determined that the species and abundance of oral microflora are closely associated with the development of upper gastrointestinal tumors, including oral, esophageal and gastric cancer. Additionally, differential abundant microbiota in patients with cancer and abnormal microorganisms inside the tumor tissue have been identified as critical markers of tumorigenesis. There is evidence to suggest that certain genera, including , along with various species, such as , can increase the risk of oral cancer. Furthermore,   is a risk factor for esophageal carcinoma, while   infections are a main cause of gastric cancer. Currently, as far as carcinogenic mechanisms of oral microorganisms are concerned, it has been hypothesized that the production of carcinogenic substances, chronic inflammation and altered cell metabolisms may be mechanisms by which oral microorganisms influence the development of upper gastrointestinal cancer. Certain phrases, including 'oral microbes', 'oral microorganism', 'oral microbiology', 'oral microflora', 'oral cancer', 'oral carcinoma', 'carcinoma of mouth', 'esophagus cancer', 'esophageal cancer', 'esophageal carcinoma', 'carcinoma of esophagus', 'gastric cancer', 'gastric carcinoma', 'stomach cancer', 'cancer of the stomach', 'carcinogenic mechanism' and 'carcinogenesis', were searched as key words in PubMed and Web of Science for articles published between 1975 to 2020. A total of 1,512 studies were obtained. After further searching the abstracts for key words, such as oral microorganisms, oral cancer, esophagus cancer, gastric cancer and carcinogenic mechanisms, 137 studies were selected. The current review systematically and comprehensively summarized the association between the oral microbiota and oral, esophageal and gastric cancer. Additionally, the current review described the carcinogenic mechanisms of oral microbes and attempted to identify common molecular mechanisms among different types of tumor. The association between upper gastrointestinal cancer therapy and oral microflora was also assessed. The present review may be used as a reference for future diagnosis and therapeutics for upper gastrointestinal tumors.
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http://dx.doi.org/10.3892/or.2021.8111DOI Listing
August 2021

Involvement of Scratch2 in GalR1-mediated depression-like behaviors in the rat ventral periaqueductal gray.

Proc Natl Acad Sci U S A 2021 Jun;118(24)

Department of Neurobiology, Beijing Key Laboratory of Neural Regeneration and Repair, Beijing Institute for Brain Disorders, Capital Medical University, 100069 Beijing, China;

Galanin receptor1 (GalR1) transcript levels are elevated in the rat ventral periaqueductal gray (vPAG) after chronic mild stress (CMS) and are related to depression-like behavior. To explore the mechanisms underlying the elevated GalR1 expression, we carried out molecular biological experiments in vitro and in animal behavioral experiments in vivo. It was found that a restricted upstream region of the gene, from -250 to -220, harbors an E-box and plays a negative role in the promoter activity. The transcription factor Scratch2 bound to the E-box to down-regulate promoter activity and lower expression levels of the gene. The expression of Scratch2 was significantly decreased in the vPAG of CMS rats. Importantly, local knockdown of Scratch2 in the vPAG caused elevated expression of GalR1 in the same region, as well as depression-like behaviors. RNAscope analysis revealed that GalR1 mRNA is expressed together with Scratch2 in both GABA and glutamate neurons. Taking these data together, our study further supports the involvement of GalR1 in mood control and suggests a role for Scratch2 as a regulator of depression-like behavior by repressing the gene in the vPAG.
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http://dx.doi.org/10.1073/pnas.1922586118DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8214687PMC
June 2021

Disease burden from COVID-19 symptoms among inpatients at the temporary military hospitals in Wuhan: a retrospective multicentre cross-sectional study.

BMJ Open 2021 05 18;11(5):e048822. Epub 2021 May 18.

Meifeng Branch, The No. 900 Hospital of Joint Logistics Support Troop of PLA, Fuzhou, China.

Objectives: We aimed to establish a set of disability weights (DWs) for COVID-19 symptoms, evaluate the disease burden of inpatients and analyse the characteristics and influencing factors of the disease.

Design: This was a multicentre retrospective cross-sectional descriptive study.

Setting: The medical records generated in three temporary military hospitals in Wuhan.

Participants: Medical records of 2702 inpatients generated from 5 February to 5 April 2020 were randomly selected for this study.

Primary And Secondary Outcome Measures: DWs of COVID-19 symptoms were determined by the person trade-off approach. The inpatients' medical records were analysed and used to calculate the disability-adjusted life years (DALYs). The mean DALY was evaluated across sex and age groups. The relationship between DALY and age, sex, body mass index, length of hospital stay, symptom duration before admission and native place was determined by multiple linear regression.

Results: For the DALY of each inpatient, severe expiratory dyspnoea, mild cough and sore throat had the highest (0.399) and lowest (0.004) weights, respectively. The average synthetic DALY and daily DALY were 2.29±1.33 and 0.18±0.15 days, respectively. Fever and fatigue contributed the most DALY at 31.36%, whereas nausea and vomiting and anxiety and depression contributed the least at 7.05%. There were significant differences between sex and age groups in both synthetic and daily DALY. Age, body mass index, length of hospital stay and symptom duration before admission were strongly related to both synthetic and daily DALY.

Conclusions: Although the disease burden was higher among women than men, their daily disease burdens were similar. The disease burden in the younger population was higher than that in the older population. Treatment at the hospitals relieved the disease burden efficiently, while a delay in hospitalisation worsened it.
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http://dx.doi.org/10.1136/bmjopen-2021-048822DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8130755PMC
May 2021

Effects of Systemic Lidocaine on Postoperative Recovery Quality and Immune Function in Patients Undergoing Laparoscopic Radical Gastrectomy.

Drug Des Devel Ther 2021 3;15:1861-1872. Epub 2021 May 3.

Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu, People's Republic of China.

Objective: This study aimed to explore the effects of lidocaine on postoperative quality of recovery (QoR) and immune function in patients undergoing laparoscopic radical gastrectomy.

Methods: In total, 135 patients were enrolled and were equally randomized to receive low-dose lidocaine (Group LL: 1.5 mg/kg bolus followed by an infusion at 1.0 mg/kg/hour) or high-dose lidocaine (Group HL: 1.5 mg/kg bolus followed by an infusion at 2.0 mg/kg/hour) or Controls (Group C: received a volume-matched normal saline at the same rate). The primary outcome was a QoR-40 score on postoperative day (POD) 1. Secondary outcomes were a QoR-40 score on POD 3, levels of inflammatory factors (IL-6, IL-10, TNF-α) and CD4T cells, CD8T cells proportions, and CD4/CD8 cell ratios and postoperative recovery of bowel function.

Results: There were no statistically significant differences in patient characteristics at baseline. The total QoR-40 scores on POD 1 in Group HL (171.4±3.89) were higher than those in Group LL (166.20±4.05) and in Group C (163.40±4.38) (adjusted <0.001). Differences in the dimension scores of QoR-40 for pain, physical comfort, and emotional state were significant across the three groups. Lidocaine administration significantly reduced the release of IL-6, IL-10, TNF-α, and attenuated immune changes induced by trauma. Kaplan-Meier curves showed that the median time to the first exhaust and defecation were shorter in the Group HL than in Groups LL and C (1.55 days vs 2.4 days vs 2.6 days, log rank <0.0001; and 2.86 days vs 3.22 days vs 3.46 days, log rank =0.002, respectively). Additionally, patients in lidocaine groups required less remifentanil consumption and experienced lower pain intensity, compared with the control group.

Conclusion: Systemic lidocaine improved postoperative recovery, alleviated inflammation and immunosuppression, and accelerated the return of bowel function, and is thus, worthy of clinical application.

Clinical Trials Registration: ChiCTR2000028934.
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http://dx.doi.org/10.2147/DDDT.S299486DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8106403PMC
May 2021

Short-term effects of land consolidation of dryland-to-paddy conversion on soil CO flux.

J Environ Manage 2021 Aug 8;292:112691. Epub 2021 May 8.

Jiangsu Key Laboratory of Coal-based Greenhouse Gas Control and Utilization, China University of Mining and Technology, Xuzhou, Jiangsu, 221008, China. Electronic address:

To improve grain production capacity, many areas in the world are shifting from rainfed agriculture to irrigated agriculture. One example of such land consolidation is dryland-to-paddy conversion. The conversion of land use pattern largely affects the stability of farmland soil, especially the soil carbon cycle. However, the mutual feedback mechanisms between carbon flux variation and environmental factors during the farmland consolidation process are still poorly known. Located in the Huang-Huai-Hai Plain China, Xuzhou is a typical area where dryland-to-paddy conversion are most widely distributed. Therefore, in this study, we have carried out dryland-to-paddy conversion by setting up two isolated rectangular fields one group planting corn in dryland (DL) and another group planting in paddy field (PF) in Xuzhou. Here, we determined the effect of dryland-to-paddy consolidation on soil CO flux in two isolated rectangular fields - the dryland (DL) cultivated with corn and the paddy field (PF) cultivated with rice. Our results showed that the soil carbon flux and temperature followed similar unimodal curves with greater soil CO flux of in PF than in DL. Surprisingly, the land conversion significantly reduced soil microbial biomass carbon and easily oxidized organic carbon by 28.55% and 29.09%, respectively. The structural equation modeling results demonstrated that the changes in soil environmental factors, including temperature, and fungal OTU numbers, were the primary drivers for the soil CO flux and soil carbon pool (P < 0.05). Overall, this study improves the understanding of the ecological impact of dryland-to-paddy conversion, providing insights into low-carbon agriculture and climate mitigation.
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http://dx.doi.org/10.1016/j.jenvman.2021.112691DOI Listing
August 2021

[Molecular chaperones facilitate soluble expression of recombinant non-toxic mutant CRM197 of diphtheria toxin in Escherichia coli].

Sheng Wu Gong Cheng Xue Bao 2021 Apr;37(4):1368-1375

Hubei Provincial Key Laboratory of Tumor Microenvironment and Immunotherapy, School of Medicine, China Three Gorges University, Yichang 443002, Hubei, China.

Diphtheria toxin is an ADP-ribosyltransferase toxic to human cells. Mutation of the active site in its catalytic domain eliminates the toxicity, but retains its immunogenicity. A non-toxic mutant of diphtheria toxin known as CRM197 protein has become an ideal carrier protein for conjugate vaccines. CRM197 can further improve its immunogenicity by cross-linking with other antigens, so it has good potential to find broad applications. Unfortunately, inclusion bodies are easily formed during the expression of recombinant CRM197 protein in Escherichia coli, which greatly reduces its yield. In order to address this problem, pG-KJE8 vector carrying molecular chaperones and plasmid pET28a-CRM197, were co-expressed in Escherichia coli. The results showed that the recombinant CRM197 protein was successfully expressed and appeared largely in inclusion bodies. The molecular chaperones DnaK, DnaJ, GrpE, GroES and GroEL5 expressed can facilitate correct and rapid folding of CRM197. Furthermore, it can also improve the recovery rate of soluble CRM197 protein. The soluble expression of CRM197 was maximized upon addition of 1.0 mmol/L IPTG, 0.5 mg L-arabinose, 5.0 ng/mL tetracycline and induction at 20oC for 16 h. The soluble CRM197 protein shows good immunoreactivity, demonstrating the molecular chaperones expressed from pG-KJE8 facilitated the soluble expression of CRM197 protein in E. coli.
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http://dx.doi.org/10.13345/j.cjb.200569DOI Listing
April 2021

Simultaneous Obstacle Avoidance and Target Tracking of Multiple Wheeled Mobile Robots With Certified Safety.

IEEE Trans Cybern 2021 May 7;PP. Epub 2021 May 7.

Collision avoidance plays a major part in the control of the wheeled mobile robot (WMR). Most existing collision-avoidance methods mainly focus on a single WMR and environmental obstacles. There are few products that cast light on the collision-avoidance between multiple WMRs (MWMRs). In this article, the problem of simultaneous collision-avoidance and target tracking is investigated for MWMRs working in the shared environment from the perspective of optimization. The collision-avoidance strategy is formulated as an inequality constraint, which has proven to be collision free between the MWMRs. The designed MWMRs control scheme integrates path following, collision-avoidance, and WMR velocity compliance, in which the path following task is chosen as the secondary task, and collision-avoidance is the primary task so that safety can be guaranteed in advance. A Lagrangian-based dynamic controller is constructed for the dominating behavior of the MWMRs. Combining theoretical analyses and experiments, the feasibility of the designed control scheme for the MWMRs is substantiated. Experimental results show that if obstacles do not threaten the safety of the WMR, the top priority in the control task is the target track task. All robots move along the desired trajectory. Once the collision criterion is satisfied, the collision-avoidance mechanism is activated and prominent in the controller. Under the proposed scheme, all robots achieve the target tracking on the premise of being collision free.
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http://dx.doi.org/10.1109/TCYB.2021.3070385DOI Listing
May 2021

Wheat embryo globulin protects against acute alcohol-induced liver injury in mice.

Food Chem Toxicol 2021 Jul 28;153:112240. Epub 2021 Apr 28.

School of Biological Engineering, Henan University of Technology, Zhengzhou, 450001, PR China; Henan Provincial Key Laboratory of Biological Processing and Nutritional Function of Wheat, Zhengzhou, 450001, PR China; Henan Cooperativity Medical Science and Technology Research Institute Co., LTD, Luoyang, 471000, PR China. Electronic address:

Wheat Embryo Globulin (WEG) is a high-quality plant-derived protein with anti-inflammatory, antioxidant, and immunity enhancement effects. WEG was prepared and characterized using free amino acid analysis, circular dichroism (CD), and scanning electron microscope (SEM). The liver protection effect of WEG on mice after acute alcohol stimulation was also investigated. Male KM mice were randomly divided into four groups (n = 10). Animals were orally administrated with WEG (60 mg/kg), silymarin (50 mg/kg), and the same volume of saline solution daily for 30 days, before administering an alcohol-intragastric injection. Results displayed that the liver index, the levels of serum total cholesterol (TC), serum triglyceride (TG), liver malondialdehyde (MDA) and the mRNA expression of CYP2E1were significantly decreased in WEG-treated mice compared with the model group. Meanwhile, the levels of serum high-density lipoprotein-cholesterol (HDL-C), hepatic reduced glutathione (GSH), superoxide dismutase (SOD) and the mRNA expression of ADH and ALDH were remarkably increased. Effect of WEG on histopathology of liver tissue confirmed its protective function. Meanwhile, GSH level of ileal was significantly increased, MDA was remarkably decreased in WEG-treated mice, which also indicated that WEG possessed a positive effect on intestinal micro ecological environment health to some extent. In conclusion, WEG is a promising agent for the prevention of acute alcoholic liver injury.
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http://dx.doi.org/10.1016/j.fct.2021.112240DOI Listing
July 2021

A deep insight into the suppression mechanism of Sedum alfredii root exudates on Pseudomonas aeruginosa based on quorum sensing.

Ecotoxicol Environ Saf 2021 Jul 23;217:112240. Epub 2021 Apr 23.

School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310012, PR China; Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, Hangzhou 310012, PR China; Instrumental Analysis Center of Zhejiang Gongshang University, Hangzhou 310012, PR China. Electronic address:

Quorum sensing (QS) plays an important role in the intensive communication between plants and microbes in the rhizosphere during the phytoremediation. This study explored the influence of the root exudates of hyperaccumulator Sedum alfredii on Pseudomonas aeruginosa based on QS. The effects of the components of root exudates, genes expression and transcription regulation of QS system (especially the las system) in Pseudomonas aeruginosa wild-type strain (WT) and rhl system mutant strain (ΔrhlI) were systematically analyzed and discussed. The WT and ΔrhlI exposed to gradient root exudates (0×, 1×, 2×, 5× and 10×) showed a concentration-corrective inhibition on protease production, with the inhibition rates of 51.4-74.5% and 31.2-50.0%, respectively. Among the components of the root exudates of Sedum alfredii, only thymol had an inhibition effects to the root exudates on the activity of protease and elastase. The inhibition rates of 50 μmol/L thymol on protease and elastase in WT were 44.7% and 24.3%, respectively, which was consistent with the variation in ΔrhlI. The gene expression of lasB declined 36.0% under the 1× root exudate treatment and 73.0% under the 50 μmol/L thymol treatment. Meanwhile, there was no significant impact on N-3-oxo-dodecanoyl-L-homoserine lactone signal production and the gene expression of lasI and lasR. Therefore, thymol from Sedum alfredii root exudates could inhibit the formation of protease and elastase in Pseudomonas aeruginosa by suppressing the expression of lasB, without any significant influence on the main las system as a potential natural QS inhibitor.
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http://dx.doi.org/10.1016/j.ecoenv.2021.112240DOI Listing
July 2021
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