Publications by authors named "Haiming Huang"

63 Publications

Multimode Grasping Soft Gripper Achieved by Layer Jamming Structure and Tendon-Driven Mechanism.

Soft Robot 2021 Jun 9. Epub 2021 Jun 9.

Department of Mechanical Engineering and Automation, Beihang University, Beijing, China.

Robotic grasping has become increasingly important in many application areas such as industrial manufacturing and logistics. Because of the diversity and uncertainty of objects and environments, common grippers with one single grasping mode face difficulties to fulfill all the tasks. Hence, we proposed a soft gripper with multiple grasping modes in this study. The gripper consists of four modular soft fingers integrated with layer jamming structure and tendon-driven mechanism. Each finger's rotating shaft of the base uses a torsional spring to decouple the bending deformation and relative rotation. An octopus-mimicking vacuum sucker is installed in the fingertip to generate suction. The effectiveness of the bending deformation and variable stiffness of the design were proved by finite element simulation. Thus, the control model of the finger was built, and the control strategy of multimode grasping of the gripper was proposed. Three control modes were designed to realize the four anthropomorphic grasping modes, including wrap, pinch, hook, and suck. Furthermore, the grasping performance was evaluated to show the abilities. The experiments indicated the superior performance of the proposed gripper and the multimode grasping ability that satisfies various grasping tasks.
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http://dx.doi.org/10.1089/soro.2020.0065DOI Listing
June 2021

Mechanism underlying long non‑coding RNA ILF3‑AS1‑mediated inhibition of cervical cancer cell proliferation, invasion and migration, and promotion of apoptosis.

Mol Med Rep 2021 Aug 3;24(2). Epub 2021 Jun 3.

Department of Anesthesiology, Sun Yat‑sen Memorial Hospital, Sun Yat‑sen University, Guangzhou, Guangdong 510120, P.R. China.

Long non‑coding RNA ILF3 divergent transcript (ILF3‑AS1) displays a tumor‑suppressing effect. StarBase predicted that the potential target microRNA (miR) of ILF3‑AS1 was miR‑454‑3p; therefore, the present study investigated the effect of ILF3‑AS1 and its target miR‑454‑3p on cervical cancer (CC). Gene Expression Profiling Interactive Analysis was used to predict the expression of ILF3‑AS1 in CC and the overall survival rate of patients. The present study demonstrated that ILF3‑AS1 expression was significantly downregulated in human CC tissues and cells compared with adjacent tissues (ANTs) and normal cervical epithelial cells (NCEs), respectively. Patients with CC with high ILF3‑AS1 expression displayed higher survival rates compared with patients with low ILF3‑AS1 expression. Cell viability, apoptosis, migration and invasion were detected by performing Cell Counting Kit‑8, flow cytometry, wound healing and Transwell assays, respectively. Compared with the negative control (NC) group, ILF3‑AS1 overexpression significantly inhibited CC cell viability and migration, but significantly increased CC cell apoptosis. Moreover, ILF3‑AS1 overexpression significantly upregulated E‑Cadherin expression levels, but significantly downregulated N‑Cadherin and snail family transcriptional repressor 1 expression levels compared with the NC group. miR‑454‑3p expression was negatively correlated with ILF3‑AS1, and highly expressed in CC tissues and cells compared with ANTs and NCEs, respectively. PTEN, which was predicted and verified as the target gene for miR‑454‑3p, was significantly downregulated in CC tissues and cells compared with ANTs and NCEs, respectively. ILF3‑AS1 expression was positively correlated with PTEN expression, and ILF3‑AS1 overexpression partially reversed the inhibitory effect of miR‑454‑3p on PTEN expression. In conclusion, the present study indicated that ILF3‑AS1 inhibited CC cell proliferation and migration, and promoted CC cell apoptosis by inhibiting epithelial‑mesenchymal transition, and ILF3‑AS1 overexpression partially reversed the inhibitory effect of miR‑454‑3p on PTEN expression.
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http://dx.doi.org/10.3892/mmr.2021.12193DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8188751PMC
August 2021

Ammonia nitrogen removal from coking wastewater and high quality gypsum recovery by struvite recycling by using calcium hydroxide as decomposer.

J Environ Manage 2021 Aug 12;292:112712. Epub 2021 May 12.

School of Environment and Civil Engineering, Dongguan University of Technology, Dongguan, 523808, China.

This study deals with the highly significant and cost-effective pretreatment of the high concentration of the Total Ammonia Nitrogen (TAN) in coking wastewater to improve the biodegradability. Struvite crystallization is a promising process for TAN removal, but the high operating cost hinders its application. To solve this problem, a novel struvite recycling process was proposed for pre-treating TAN present in the coking wastewater, within which struvite was decomposed in the solid-liquid system using Ca(OH) as the decomposer. The results indicates that 91% of ammonium in struvite could be stripped out from the decomposition solution, with Ca(OH):NH in the molar ratio of 2:1, temperature at 35 °C and a gas to liquid volume ratio of 3500. The resulting solution, post the escape of the ammonia, was dissolved by sulfuric acid. Approximately 100% of the phosphate and magnesium were observed to be released from the insoluble phosphate compounds, resulting in the formation of high-purity gypsum. A TAN removal efficiency of 89% could be achieved by reusing the supernatant after the dissolution of the decomposition product, at pH 9.5 and the Mg:TAN:PO-P molar ratio of 1.2:1:1. The pilot-scale test demonstrated that approximately 86% TAN was removed from the coking wastewater and the purity of recovered could reach over 99%. Further economic analysis proves that the operation cost of the proposed process is 0.55$ per m of coking wastewater, showing a 73% cost reduction when compared to struvite crystallization without recycling.
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http://dx.doi.org/10.1016/j.jenvman.2021.112712DOI Listing
August 2021

Combination of Urine Exosomal mRNAs and lncRNAs as Novel Diagnostic Biomarkers for Bladder Cancer.

Front Oncol 2021 27;11:667212. Epub 2021 Apr 27.

Department of Clinical Laboratory, Peking University First Hospital, Beijing, China.

Background: The recent discovery of miRNAs and lncRNAs in urine exosomes has emerged as promising diagnostic biomarkers for bladder cancer (BCa). However, mRNAs as the direct products of transcription has not been well evaluated in exosomes as biomarkers for BCa diagnosis. The purpose of this study was to identify tumor progression-related mRNAs and lncRNAs in urine exosomes that could be used for detection of BCa.

Methods: RNA-sequencing was performed to identify tumor progression-related biomarkers in three matched superficial tumor and deep infiltrating tumor regions of muscle-invasive bladder cancer (MIBC) specimens, differently expressed mRNAs and lncRNAs were validated in TCGA dataset (n = 391) in the discovery stage. Then candidate RNAs were chosen for evaluation in urine exosomes of a training cohort (10 BCa and 10 healthy controls) and a validation cohort (80 BCa and 80 healthy controls) using RT-qPCR. The diagnostic potential of the candidates were evaluated by receiver operating characteristic (ROC) curves.

Results: RNA sequencing revealed 8 mRNAs and 32 lncRNAs that were significantly upregulated in deep infiltrating tumor region. After validation in TCGA database, 10 markedly dysregulated RNAs were selected for further investigation in urine exosomes, of which five (mRNAs: KLHDC7B, CASP14, and PRSS1; lncRNAs: MIR205HG and GAS5) were verified to be significantly dysregulated. The combination of the five RNAs had the highest AUC to disguising the BCa (0.924, 95% CI, 0.875-0.974) or early stage BCa patients (0.910, 95% CI, 0.850 to 0.971) from HCs. The expression levels of these five RNAs were correlated with tumor stage, grade, and hematuria degrees.

Conclusions: These findings highlight the potential of urine exosomal mRNAs and lncRNAs profiling in the early diagnosis and provide new insights into the molecular mechanisms involved in BCa.
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http://dx.doi.org/10.3389/fonc.2021.667212DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8111292PMC
April 2021

Osthole Attenuates Macrophage Activation in Experimental Asthma by Inhibitingthe NF-ĸB/MIF Signaling Pathway.

Front Pharmacol 2021 22;12:572463. Epub 2021 Mar 22.

Department of Respiratory and Critical Care Medicine, Affiliated Hospital of Guilin Medical University, Guilin, China.

Inhibition of activated macrophages is an alternative therapeutic strategy for asthma. We investigated whether a coumarin compound, osthole, isolated from (L.) Cuss, alleviated macrophage activation and . Osthole could reduce expression of a marker of activated macrophages, cluster of differentiation (CD)206, in an ovalbumin-challenge model of asthma in mice. Osthole could also inhibit infiltration of inflammatory cells, collagen deposition and production of proinflammatory cytokines [interleukin (IL)-1β, tumor necrosis factor-ɑ, macrophage migration inhibitory factor (MIF)] in asthmatic mice. , expression of phosphorylated-IĸBɑ, MIF and M2 cytokines (Ym-1, Fizz-1, arginase-1) in IL-4-induced macrophages decreased upon exposure to the NF-ĸB inhibitor MG-132. In our short hairpin (sh)RNA-MIF-knockdown model, reduced expression of M2 cytokines was detected in the IL-4 + shRNA-MIF group. Osthole could attenuate the proliferation and migration of an IL-4-induced rat alveolar macrophages line (NR8383). Osthole could reduce IL-4-induced translocation of nuclear factor-kappa B (NF-ĸB) in NR8383 cells. Collectively, our results suggest that osthole ameliorates macrophage activation in asthma by suppressing the NF-ĸB/MIF signaling pathway, and might be a potential agent for treating asthma.
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http://dx.doi.org/10.3389/fphar.2021.572463DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8020258PMC
March 2021

Revisiting the phosphotyrosine binding pocket of Fyn SH2 domain led to the identification of novel SH2 superbinders.

Protein Sci 2021 Mar 31;30(3):558-570. Epub 2020 Dec 31.

Department of Antibody Engineering, Shanghai Asia United Antibody Medical Co., Ltd, Shanghai, China.

Protein engineering through directed evolution is an effective way to obtain proteins with novel functions with the potential applications as tools for diagnosis or therapeutics. Many natural proteins have undergone directed evolution in vitro in the test tubes in the laboratories worldwide, resulting in the numerous protein variants with novel or enhanced functions. we constructed here an SH2 variant library by randomizing 8 variable residues in its phosphotyrosine (pTyr) binding pocket. Selection of this library by a pTyr peptide led to the identification of SH2 variants with enhanced affinities measured by EC50. Fluorescent polarization was then applied to quantify the binding affinities of the newly identified SH2 variants. As a result, three SH2 variants, named V3, V13 and V24, have comparable binding affinities with the previously identified SH2 triple-mutant superbinder. Biolayer Interferometry assay was employed to disclose the kinetics of the binding of these SH2 superbinders to the phosphotyrosine peptide. The results indicated that all the SH2 superbinders have two-orders increase of the dissociation rate when binding the pTyr peptide while there was no significant change in their associate rates. Intriguingly, though binding the pTyr peptide with comparable affinity with other SH2 superbinders, the V3 does not bind to the sTyr peptide. However, variant V13 and V24 have cross-reactivity with both pTyr and sTyr peptides. The newly identified superbinders could be utilized as tools for the identification of pTyr-containing proteins from tissues under different physiological or pathophysiological conditions and may have the potential in the therapeutics.
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http://dx.doi.org/10.1002/pro.4012DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7888540PMC
March 2021

The Role of Macrophage Migration Inhibitory Factor (MIF) in Asthmatic Airway Remodeling.

Allergy Asthma Immunol Res 2021 Jan;13(1):88-105

Department of Respiratory and Critical Care Medicine, The Second Affiliated Hospital of Guilin Medical University, Guilin, China.

Purpose: Recent studies have demonstrated that macrophage migration inhibitory factor (MIF) is of importance in asthmatic inflammation. The role of MIF in modulating airway remodeling has not yet been thoroughly elucidated to date. In the present study, we hypothesized that MIF promoted airway remodeling by intensifying airway smooth muscle cell (ASMC) autophagy and explored the specific mechanisms.

Methods: MIF knockdown in the lung tissues of C57BL/6 mice was conducted by instilling intratracheally adeno-associated virus (AAV) vectors (MIF-mutant AAV9) into mouse lung tissues. Mice genetically deficient in the autophagy marker ATG5 (ATG5) was used to detect the role of autophagy in ovalbumin (OVA)-asthmatic murine models. Moreover, to block the expression of MIF and CD74 models, inhibitors, antibodies and lentivirus transfection techniques were employed.

Results: First, MIF knockdown in the lung tissues of mice showed markedly reduced airway remodeling in OVA murine mice models. Secondly, ASMC autophagy was increased in the OVA-challenged models. Mice genetically deficient in the autophagy marker ATG5 (ATG5) that were primed and challenged with OVA showed lower airway remodeling than genetically wild-type asthmatic mice. Thirdly, MIF can induce ASMC autophagy . Moreover, the cellular source of MIF which promoted ASMC autophagy was macrophages. Finally, MIF promoted ASMC autophagy in a CD74-dependent manner.

Conclusions: MIF can increase asthmatic airway remodeling by enhancing ASMC autophagy. Macrophage-derived MIF can promote ASMC autophagy by targeting CD74.
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http://dx.doi.org/10.4168/aair.2021.13.1.88DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7680835PMC
January 2021

Diagnostic accuracy of 14-3-3 η protein in rheumatoid arthritis: A meta-analysis.

Int J Rheum Dis 2020 Nov 10;23(11):1443-1451. Epub 2020 Sep 10.

Department of Respiratory and Critical Care Medicine, Guangxi Zhuang Autonomous Region Education Department Key Laboratory of Respiratory Diseases, Affiliated Hospital of Guilin Medical University, Guilin, China.

Aim: To evaluate the overall diagnostic performance of 14-3-3 η protein in patients with rheumatoid arthritis (RA).

Methods: PubMed, EMBASE, and Web of Science were searched to acquire eligible studies. Articles published in English before 20 February 2020 were included. Quality Assessment of Diagnostic Accuracy Studies 2 was used to evaluate the risk of bias and application concern of the included articles. Pooled analysis of diagnostic indicators of 14-3-3 η protein for RA was conducted by using a random effects model. Subgroup analysis was used to explore the sources of heterogeneity. Deeks' funnel plot asymmetry test was used to evaluate for the presence of publication bias.

Results: A total of 13 studies (1554 positive and 1934 negative participants) were included. The pooled sensitivity and specificity were 0.73 (95% CI 0.71-0.75) and 0.88 (95% CI 0.87-0.90), respectively. The pooled positive/negative likelihood were 5.98 (95% CI 4.39-8.14) and 0.28 (95% CI 0.21-0.37), respectively. In addition, the pooled diagnostic odds ratio was 23.48 (95% CI 13.76-40.08) and the area under curve was 0.9245. The results of subgroup analysis indicated that ethnicity and control group might be the source of heterogeneity. The results of sensitivity analysis were stable. No significant publication bias was found.

Conclusions: The current evidence indicated that 14-3-3 η protein has moderate accuracy for the diagnosis of RA.
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http://dx.doi.org/10.1111/1756-185X.13921DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7756802PMC
November 2020

Persulfate oxidation for alternative sludge treatment and nutrient recovery: An assessment of technical and economic feasibility.

J Environ Manage 2020 Oct 15;272:111007. Epub 2020 Jul 15.

School of Environment and Civil Engineering, Dongguan University of Technology, Dongguan 523808, China; Hebei Key Laboratory of Applied Chemistry, School of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004, PR China.

The introduce of tighter waste disposal regulations and increasing resource scarcity make the re-utilization of waste activated sludge a hot and crucial research topic. Compared with traditional sludge disposal technologies (e.g. landfill and incineration), advanced oxidation processes have been proven to be an environmentally friendly method for sludge stabilization and disintegration. However, the effectiveness of persulfate oxidation for sludge degradation, and the re-utilization of its embedded nutrients have been rarely reported. Therefore, this work is to investigate the technical and economic feasibility of using persulfate oxidation and struvite precipitation for sludge degradation and nutrient recovery. The results show that with the assistance of ultraviolet radiation, released phosphate and ammonia nitrogen from sludge could reach 233.4 and 265.6 mg/L. Besides, 92.8% phosphate and 32.6% ammonia-nitrogen could be recovered by struvite precipitation at a pH of 9.5, with an Mg: P molar ratio of 1.1:1. The economic analysis shows that the operational cost of the proposed process was 25% higher than traditional sludge disposal (267.5 $/ton), but its capital investment is much lower. Investigations on chemical dosage minimization, energy reclamation and process optimization are suggested to reduce the process's operating cost in the future.
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http://dx.doi.org/10.1016/j.jenvman.2020.111007DOI Listing
October 2020

Crk1/2 and CrkL play critical roles in maintaining podocyte morphology and function.

Exp Cell Res 2020 09 11;394(1):112135. Epub 2020 Jun 11.

Department of Clinical Laboratory, Peking University First Hospital, Beijing, China. Electronic address:

Podocytes are actin-rich epithelial cells whose effacement and detachment are the main cause of glomerular disease. Crk family proteins: Crk1/2 and CrkL are reported to be important intracellular signaling proteins that are involved in many biological processes. However, the roles of them in maintaining podocyte morphology and function remain poorly understood. In this study, specific knocking down of Crk1/2 and CrkL in podocytes caused abnormal cell morphology, actin cytoskeleton rearrangement and dysfunction in cell adhesion, spreading, migration, and viability. The p130Cas, focal adhesion kinase, phosphatidylinositol 3-kinase/Akt, p38 and JNK signaling pathways involved in these alterations. Furthermore, knocking down CrkL alone conferred a more modest phenotype than did the Crk1/2 knockdown and the double knockdown. Kidney biopsy specimens from patients with focal segmental glomerulosclerosis and minimal change nephropathy showed downregulation of Crk1/2 and CrkL in glomeruli. In zebrafish embryos, Crk1/2 and CrkL knockdown compromised the morphology and caused abnormal glomerular development. Thus, our results suggest that Crk1/2 and CrkL expression are important in podocytes; loss of either will cause podocyte dysfunction, leading to foot process effacement and podocyte detachment.
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http://dx.doi.org/10.1016/j.yexcr.2020.112135DOI Listing
September 2020

Investigation into lanthanum-coated biochar obtained from urban dewatered sewage sludge for enhanced phosphate adsorption.

Sci Total Environ 2020 Apr 22;714:136839. Epub 2020 Jan 22.

School of Environment and Civil Engineering, Dongguan University of Technology, Dongguan 523808, China.

Phosphate adsorption using metal-modified biochar has awakened much attention and triggered extensive research. In this study, the effect of lanthanum (La)-modified sludge using impregnation-co-precipitation was used for phosphate adsorption. Consequently, La-coated biochar at a pyrolysis temperature of 600 °C had the highest phosphate adsorption and the lowest heavy metal leaching potential. The treatment of virgin biochar with alkali before La loading was found to be beneficial for the increase of phosphate adsorption capacity. The adsorption kinetics was well depicted by the pseudo-second-order model, and indicating that intraparticle diffusion played a crucial role in the adsorption process. The good fitness between adsorption data and the Langmuir isotherm model showed a maximal adsorption capacity of 93.91 mg/g, where phosphate absorption was highly correlated to its concentration in the solution. The La-coated biochar showed high adsorption capacity when the solution pH varied from 3.0 to 6.0, and was insensitive to the coexisting chloride, nitrate, sulfate, bicarbonate and citrate. Moreover, the adsorption mechanism was further explored by using Zeta potential analysis, FTIR and XPS, indicating that the phosphate is adsorbed through electrostatic attraction in the form of the inner-sphere complexation. All the results suggested that the sludge-based biochar, as a support material for La, could serve as a promising adsorbent for phosphate in real applications.
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http://dx.doi.org/10.1016/j.scitotenv.2020.136839DOI Listing
April 2020

A Synthetic Human Antibody Antagonizes IL-18Rβ Signaling Through an Allosteric Mechanism.

J Mol Biol 2020 02 15;432(4):1169-1182. Epub 2020 Jan 15.

Laboratory of Antibody Engineering, Shanghai Institute for Advanced Immunochemical Studies, ShanghaiTech University, Shanghai, China. Electronic address:

The interleukin-18 subfamily belongs to the interleukin-1 family and plays an important role in modulating innate and adaptive immune responses. Dysregulation of IL-18 has been implicated in or correlated with numerous diseases, including inflammatory diseases, autoimmune disorders, and cancer. Thus, blockade of IL-18 signaling may offer therapeutic benefits in many pathological settings. Here, we report the development of synthetic human antibodies that target human IL-18Rβ and block IL-18-mediated IFN-γ secretion by inhibiting NF-κB and MAPK dependent pathways. The crystal structure of a potent antagonist antibody in complex with IL-18Rβ revealed inhibition through an unexpected allosteric mechanism. Our findings offer a novel means for therapeutic intervention in the IL-18 pathway and may provide a new strategy for targeting cytokine receptors.
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http://dx.doi.org/10.1016/j.jmb.2020.01.012DOI Listing
February 2020

Dual surface structured light vision system based on multidimensional parameter coding.

Appl Opt 2019 Sep;58(26):7212-7221

A dual surface structured light vision system based on the theory of multidimensional parameter coding is proposed in this paper that can provide a new high-performance and adaptive encoding robot vision perception system. Specifically, the dual surface structured light consists of an auxiliary light source and a principal structured light. Scene images from the auxiliary structured light determine the parameters of the principal structured light. The vision process system can adaptively encode the principal structured light according to types and numbers of parameters. The image formed by the encoded principal structured light can reflect the depth change details of the target object and guide the robot to locate the target object quickly and accurately. The simulation and industrial experiments show that the dual surface structured light vision system has wider application scenarios and higher accuracy than the traditional structured light vision system. According to different industrial scenes, the positioning accuracy of the vision system can reach 0.1 mm to 20 μm in 0.8 s.
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http://dx.doi.org/10.1364/AO.58.007212DOI Listing
September 2019

Removal of phosphate from aqueous solution by dolomite-modified biochar derived from urban dewatered sewage sludge.

Sci Total Environ 2019 Oct 1;687:460-469. Epub 2019 Jun 1.

School of Environment and Civil Engineering, Dongguan University of Technology, Dongguan 523808, China; Hebei Key Laboratory of Applied Chemistry, School of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004, China.

Excessive phosphorus emission is mainly responsible for eutrophication. Recently, the application of modified biochars for phosphorus removal from aqueous solution has set off a boom. In the present study, a novel modified biochar was developed, from urban sewage sludge by decorating dolomite according to the dried mass ratio of sludge to dolomite being 1:1. The experimental results showed that the adsorption process preferred lower pH, with the biochar under investigation exhibiting high phosphate removal efficiency of 96.8% at the adsorbent dosage of 2.6 g/L and the initial solution pH of 4.5. Moreover, for the tested biochar, the phosphate removal kinetics data at different temperatures were all well fitted by the pseudo-second-order model, thereby establishing the endothermic nature of the adsorption process. Furthermore, the phosphate removal data upon being well fitted by the Langmuir model showed the maximal removal capacity of 29.18 mg/g. Further, for determining the mechanism involved in the removal process, SEM, XRD, and FTIR analysis were carried out, which in turn revealed that the phosphate combines with the biochar via electrostatic attraction, thereby forming a new outer-sphere surface complex and inner-sphere surface complex in the acidic condition. Additionally, the calcium and magnesium precipitation of phosphate may contribute to the removal of phosphate in the adsorption process. The presence of SO, HCO, and CHOCOO could negatively affect the removal of phosphate, while CHCOO had a positive effect on the adsorption of phosphate on the biochar. Thus, an economic assessment showed that the proposed adsorption process had a commercial attraction.
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http://dx.doi.org/10.1016/j.scitotenv.2019.05.400DOI Listing
October 2019

Exchange-dependent spin polarized transport and phase transition in a triple monomer molecule.

Phys Chem Chem Phys 2019 Jun 16;21(21):11158-11167. Epub 2019 May 16.

Advanced Functional Material and Photoelectric Technology Research Institution, School of Science, Hubei University of Automotive Technology, Shiyan 442002, People's Republic of China.

Molecular junctions contribute significantly to the fundamental understanding of the quantum information technologies in molecular spintronics. In this paper, with the aid of the state of the art numerical renormalization group method, we find a triple monomer molecule structure with strong electron-electron interactions could be a potential candidate for a multifunctional spin polarizer when an external magnetic field along the z axis is applied. It is demonstrated that the polarizing scenarios depend closely on the inter-orbital exchange couplings, and results in several kinds of spin polarizers, e.g., the unidirectional, the bidirectional, the dual, and the ternary spin polarizers. We show in detail the related phase diagram, and conclude the Zeeman effect and the charge switching for the bonding, anti-bonding and non-bonding orbitals are responsible for the spin polarizing transport. We stress even when the energy levels are chosen beyond the Kondo regime, the structure still shows a promising platform for molecular spintronics components.
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http://dx.doi.org/10.1039/c9cp01350dDOI Listing
June 2019

Theoretical assessment of wettability on silane coatings: from hydrophilic to hydrophobic.

Phys Chem Chem Phys 2019 Apr;21(16):8257-8263

School of Physics and Electronic Engineering, Guangzhou University, Guangzhou, 510006, P. R. China.

The potential distribution and work function of a graphene surface modified by various types of silanes are investigated by first principles quantum mechanical calculations to establish its surface hydrophobicity hierarchy. It is found that the work function relies on the electronegativity of atoms on silane. The localization feature of interaction between silane and the graphene surface is demonstrated by the electron density difference. The work function is demonstrated to be a critical quantity in understanding the surface polarizability and thereby the surface wetting properties. By performing contact angle measurements experimentally using water as the probe fluid, surfaces grafted with different silanes show hydrophobicity variation that is found to follow the reverse trend to that of the proposed surface polarizability obtained through the work function calculation. The work function-dependent contact angle can be fitted with a linear equation.
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http://dx.doi.org/10.1039/c9cp01232jDOI Listing
April 2019

High-efficiency electrochemical degradation of antiviral drug abacavir using a penetration flux porous Ti/SnO-Sb anode.

Chemosphere 2019 Jun 9;225:304-310. Epub 2019 Mar 9.

Research Center for Eco-environmental Engineering, Dongguan University of Technology, Dongguan, 523808, China. Electronic address:

Electrochemical degradation of antiviral drug abacavir was investigated by using a penetration flux porous Ti/SnO-Sb anode prepared by sol-gel method. The effects of applied current density, initial pH, and inorganic anions on the degradation kinetics were systematically studied. Degradation efficiency more than 97% was performed in only 10 min at a current density of 0.2 mA cm. The corresponding degradation rate constant and the lowest electrical energy per order were calculated to be 0.36 min and 6.5 mWh L, respectively. Extending the reaction duration to 5 h, 53.3% of TOC removal was observed. The results indicated that effective degradation of abacavir appeared in the penetration flux porous Ti/SnO-Sb anode with a very low energy consumption. Furthermore, the electrochemical intermediate products and the reaction site during abacavir degradation were detected and recognized. The quantitative structure-activity relationship model revealed that the potential risks of abacavir to the aquatic organism, such as fish, greatly decreased after flowing through the penetration flux porous Ti/SnO-Sb anode.
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http://dx.doi.org/10.1016/j.chemosphere.2019.03.036DOI Listing
June 2019

Fabrication and Highly Efficient Dye Removal Characterization of Beta-Cyclodextrin-Based Composite Polymer Fibers by Electrospinning.

Nanomaterials (Basel) 2019 Jan 20;9(1). Epub 2019 Jan 20.

State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, China.

Dye wastewater is one of the most important problems to be faced and solved in wastewater treatment. However, the treatment cannot be single and simple adsorption due to the complexity of dye species. In this work, we prepared novel composite fiber adsorbent materials consisting of ε-polycaprolactone (PCL) and beta-cyclodextrin-based polymer (PCD) by electrospinning. The morphological and spectral characterization demonstrated the successful preparation of a series of composite fibers with different mass ratios. The obtained fiber materials have demonstrated remarkable selective adsorption for MB and 4-aminoazobenzene solutions. The addition of a PCD component in composite fibers enhanced the mechanical strength of membranes and changed the adsorption uptake due to the cavity molecular structure via host⁻guest interaction. The dye removal efficiency could reach 24.1 mg/g towards 4-aminoazobenzene. Due to the admirable stability and selectivity adsorption process, the present prepared beta-cyclodextrin-based composite fibers have demonstrated potential large-scale applications in dye uptake and wastewater treatment.
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http://dx.doi.org/10.3390/nano9010127DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6359147PMC
January 2019

Facile Preparation of Self-Assembled Polydopamine-Modified Electrospun Fibers for Highly Effective Removal of Organic Dyes.

Nanomaterials (Basel) 2019 Jan 18;9(1). Epub 2019 Jan 18.

State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, China.

Polydopamine (PDA) nanoparticles can be used as an adsorbent with excellent adsorption capacity. However, nanosized adsorbents are prone to aggregation and thus are severely limited in the field of adsorption. In order to solve this problem, we utilized polydopamine in-situ oxidation self-polymerization on the surface of polycaprolactone (PCL)/polyethylene oxide (PEO) electrospun fiber after solvent vapor annealing (SVA) treatment, and successfully designed and prepared a PCL/[email protected] composite membrane. The SVA treatment regulated the microscopic morphology of smooth PCL/PEO electrospun fibers that exhibited a pleated microstructure, increasing the specific surface area, and providing abundant active sites for the anchoring of PDA nanoparticles. The PCL/[email protected] composite obtained by chemical modification of PDA demonstrated numerous active sites for the adsorption of methylene (MB) and methyl orange (MO). In addition, the PCL/[email protected] composites were reusable several times with good reutilization as adsorbents. Therefore, we have developed a highly efficient and non-agglomerated dye adsorbent that exhibits potential large-scale application in dye removal and wastewater purification.
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http://dx.doi.org/10.3390/nano9010116DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6358777PMC
January 2019

Selection of anesthesia for lower extremity surgery of patients with Proteus Syndrome.

J Clin Anesth 2019 08 29;55:79-82. Epub 2018 Dec 29.

Department of Anesthesiology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China. Electronic address:

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http://dx.doi.org/10.1016/j.jclinane.2018.12.036DOI Listing
August 2019

Influence of process parameters on the heavy metal (Zn, Cu and Cr) content of struvite obtained from synthetic swine wastewater.

Environ Pollut 2019 Feb 16;245:658-665. Epub 2018 Nov 16.

Department of Chemical & Materials Engineering, University of Auckland, New Zealand.

Struvite recovered from swine wastewater can be used as a good slow release fertilizer. Nevertheless, the presence of heavy metals would be easily precipitated with struvite and increase the ecological risk for its agricultural use. This paper investigated the possibility of using process variables for heavy metal (Cu, Zn and Cr) minimization during struvite crystallization in swine wastewater. The heavy metal content, effect ratios (ER) of the citric acid concentration under varying conditions were tested and their SEM, EDS and XRD patterns were compared for morphology analysis. The results show that an increase in pH decreased the content of Cu, Zn and Cr in recovered precipitates. Heavy metal content in the precipitates increased markedly with their initial concentrations in the solution. The effect ratio calculation indicates that Cr has the strongest co-precipitation potential, followed by Zn and Cu. An increase in citric acid concentration reduced the heavy metal removal efficiency (14.3, 27.7 and 28.1% for Cu, Zn and Cr, respectively) but did not decrease their content in struvite precipitates. What is more, increase of total ammonia nitrogen (TAN) to soluble phosphate molar ratio significantly decreased Cu, Zn removal efficiency (52.2 and 50% respectively), while Mg:POP molar ratio had much less effect.
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http://dx.doi.org/10.1016/j.envpol.2018.11.046DOI Listing
February 2019

Surface Loops in a Single SH2 Domain Are Capable of Encoding the Spectrum of Specificity of the SH2 Family.

Mol Cell Proteomics 2019 02 27;18(2):372-382. Epub 2018 Nov 27.

Department of Biochemistry, Schulich School of Medicine and Dentistry, Western University, London, Ontario N6A 5C1;. Electronic address:

Src homology 2 (SH2) domains play an essential role in cellular signal transduction by binding to proteins phosphorylated on Tyr residue. Although Tyr phosphorylation (pY) is a prerequisite for binding for essentially all SH2 domains characterized to date, different SH2 domains prefer specific sequence motifs C-terminal to the pY residue. Because all SH2 domains adopt the same structural fold, it is not well understood how different SH2 domains have acquired the ability to recognize distinct sequence motifs. We have shown previously that the EF and BG loops that connect the secondary structure elements on an SH2 domain dictate its specificity. In this study, we investigated if these surface loops could be engineered to encode diverse specificities. By characterizing a group of SH2 variants selected by different pY peptides from phage-displayed libraries, we show that the EF and BG loops of the Fyn SH2 domain can encode a wide spectrum of specificities, including all three major specificity classes ( + 2, + 3 and + 4) of the SH2 domain family. Furthermore, we found that the specificity of a given variant correlates with the sequence feature of the bait peptide used for its isolation, suggesting that an SH2 domain may acquire specificity by co-evolving with its ligand. Intriguingly, we found that the SH2 variants can employ a variety of different mechanisms to confer the same specificity, suggesting the EF and BG loops are highly flexible and adaptable. Our work provides a plausible mechanism for the SH2 domain to acquire the wide spectrum of specificity observed in nature through loop variation with minimal disturbance to the SH2 fold. It is likely that similar mechanisms may have been employed by other modular interaction domains to generate diversity in specificity.
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http://dx.doi.org/10.1074/mcp.RA118.001123DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6356082PMC
February 2019

Alleviating Na effect on phosphate and potassium recovery from synthetic urine by K-struvite crystallization using different magnesium sources.

Sci Total Environ 2019 Mar 19;655:211-219. Epub 2018 Nov 19.

Center for Environmental Engineering Design, Chinese Academy of Environmental Sciences, Beijing 100012, China.

Human urine is characterized by high concentrations of nitrogen (N), phosphorus (P) and potassium (K), of which the P and K can be recovered as K-struvite crystals. This study first investigated the formation of Na-struvite because of the high Na present in the urine. From the results, the optimal pH for the Na-struvite crystallization was observed to be 12, and the rise in the Na concentration distinctly favored the Na-struvite formation. As magnesium needed to be added to induce the K-struvite crystallization, several magnesium sources including MgCl, Mg sacrificial electrode and Mg(OH) were applied to recover P and K from synthetic urine. The findings indicated that when MgCl was used as the magnesium source, the K removal could be slightly enhanced by prolonging the reaction time, which would correspondingly decrease the Na concentration in the precipitates; besides, the intermittent addition of MgCl could noticeably improve the removal efficiency of K by 6%, but simultaneously raise the Na content in the precipitates recovered. With respect to the use of the Mg sacrificial electrode, the recovery efficiencies of the P and K from synthetic urine were close to those with the use of MgCl. However, when Mg(OH) was used as the magnesium source, the recovery efficiencies of P and K achieved only roughly 50%, which was much lower than those noted when MgCl and the Mg sacrificial electrode were employed. A comprehensive analysis revealed that the MgCl was the best magnesium source for the K-struvite crystallization, followed by the Mg sacrificial electrode and Mg(OH).
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http://dx.doi.org/10.1016/j.scitotenv.2018.11.259DOI Listing
March 2019

Allosteric Modulation of Binding Specificity by Alternative Packing of Protein Cores.

J Mol Biol 2019 01 22;431(2):336-350. Epub 2018 Nov 22.

The Donnelly Centre for Cellular and Biomolecular Research. University of Toronto, Toronto, ON M5S 3E1, Canada; Banting and Best Department of Medical Research. University of Toronto, Toronto, ON M5S 3E1, Canada; Department of Molecular Genetics. University of Toronto, Toronto, ON M5S 3E1, Canada. Electronic address:

Hydrophobic cores are often viewed as tightly packed and rigid, but they do show some plasticity and could thus be attractive targets for protein design. Here we explored the role of different functional pressures on the core packing and ligand recognition of the SH3 domain from human Fyn tyrosine kinase. We randomized the hydrophobic core and used phage display to select variants that bound to each of three distinct ligands. The three evolved groups showed remarkable differences in core composition, illustrating the effect of different selective pressures on the core. Changes in the core did not significantly alter protein stability, but were linked closely to changes in binding affinity and specificity. Structural analysis and molecular dynamics simulations revealed the structural basis for altered specificity. The evolved domains had significantly reduced core volumes, which in turn induced increased backbone flexibility. These motions were propagated from the core to the binding surface and induced significant conformational changes. These results show that alternative core packing and consequent allosteric modulation of binding interfaces could be used to engineer proteins with novel functions.
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http://dx.doi.org/10.1016/j.jmb.2018.11.018DOI Listing
January 2019

Engineered SH2 domains with tailored specificities and enhanced affinities for phosphoproteome analysis.

Protein Sci 2019 02 24;28(2):403-413. Epub 2018 Dec 24.

Department of Biochemistry, University of Toronto, Toronto, Ontario, M5S 1A8, Canada.

Protein phosphorylation is the most abundant post-translational modification in cells. Src homology 2 (SH2) domains specifically recognize phosphorylated tyrosine (pTyr) residues to mediate signaling cascades. A conserved pocket in the SH2 domain binds the pTyr side chain and the EF and BG loops determine binding specificity. By using large phage-displayed libraries, we engineered the EF and BG loops of the Fyn SH2 domain to alter specificity. Engineered SH2 variants exhibited distinct specificity profiles and were able to bind pTyr sites on the epidermal growth factor receptor, which were not recognized by the wild-type Fyn SH2 domain. Furthermore, mass spectrometry showed that SH2 variants with additional mutations in the pTyr-binding pocket that enhanced affinity were highly effective for enrichment of diverse pTyr peptides within the human proteome. These results showed that engineering of the EF and BG loops could be used to tailor SH2 domain specificity, and SH2 variants with diverse specificities and high affinities for pTyr residues enabled more comprehensive analysis of the human phosphoproteome. STATEMENT: Src Homology 2 (SH2) domains are modular domains that recognize phosphorylated tyrosine embedded in proteins, transducing these post-translational modifications into cellular responses. Here we used phage display to engineer hundreds of SH2 domain variants with altered binding specificities and enhanced affinities, which enabled efficient and differential enrichment of the human phosphoproteome for analysis by mass spectrometry. These engineered SH2 domain variants will be useful tools for elucidating the molecular determinants governing SH2 domains binding specificity and for enhancing analysis and understanding of the human phosphoproteome.
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http://dx.doi.org/10.1002/pro.3551DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6319756PMC
February 2019

Comparison of different K-struvite crystallization processes for simultaneous potassium and phosphate recovery from source-separated urine.

Sci Total Environ 2019 Feb 19;651(Pt 1):787-795. Epub 2018 Sep 19.

Hebei Key Laboratory of Applied Chemistry, School of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004, PR China.

Controlled K-struvite crystallization is an attractive technology to simultaneously recover phosphate and potassium from urine. This study investigated the recovery of phosphate and potassium from source-separated urine by K-struvite crystallization using different use models of low-grade MgO (LG-MgO): LG-MgO alone (model 1, M1), LG-MgO plus phosphorus acid (model 2, M2), and a pre-formed stabilizing agent by adding LG-MgO plus phosphorus acid (model 3, M3). Results showed that 100% phosphate and 25% K could be recovered from urine by M1. M2 at an MgO:K:P molar ratio of 4:1:1.6 provided a maximum P and K recovery efficiency at 100% and 70%. M3 achieved a same K-removal efficiency as M2, but the phosphate recovery efficiency was lower than that of M2 due to the dissolution of phosphate in the stabilizing agent. K-struvite crystallization was closely accompanied by severe co-precipitation of Na-struvite. Increasing the Na concentration markedly improved the ability of Na co-precipitation, but the variation of pH did not affect the competition precipitation of K and Na. When the Na:K molar ratio was >10, the precipitation of Na was more than that of K. A process performance evaluation indicated that M3 is more suitable for simultaneous K and P recovery from source-separated urine.
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http://dx.doi.org/10.1016/j.scitotenv.2018.09.232DOI Listing
February 2019

Structural basis for arginine methylation-independent recognition of PIWIL1 by TDRD2.

Proc Natl Acad Sci U S A 2017 11 8;114(47):12483-12488. Epub 2017 Nov 8.

Structural Genomics Consortium, University of Toronto, Toronto, ON M5G 1L7, Canada;

The P-element-induced wimpy testis (PIWI)-interacting RNA (piRNA) pathway plays a central role in transposon silencing and genome protection in the animal germline. A family of Tudor domain proteins regulates the piRNA pathway through direct Tudor domain-PIWI interactions. Tudor domains are known to fulfill this function by binding to methylated PIWI proteins in an arginine methylation-dependent manner. Here, we report a mechanism of methylation-independent Tudor domain-PIWI interaction. Unlike most other Tudor domains, the extended Tudor domain of mammalian Tudor domain-containing protein 2 (TDRD2) preferentially recognizes an unmethylated arginine-rich sequence from PIWI-like protein 1 (PIWIL1). Structural studies reveal an unexpected Tudor domain-binding mode for the PIWIL1 sequence in which the interface of Tudor and staphylococcal nuclease domains is primarily responsible for PIWIL1 peptide recognition. Mutations disrupting the TDRD2-PIWIL1 interaction compromise piRNA maturation via 3'-end trimming in vitro. Our work presented here reveals the molecular divergence of the interactions between different Tudor domain proteins and PIWI proteins.
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http://dx.doi.org/10.1073/pnas.1711486114DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5703303PMC
November 2017

Comprehensive Analysis of the Human SH3 Domain Family Reveals a Wide Variety of Non-canonical Specificities.

Structure 2017 10 7;25(10):1598-1610.e3. Epub 2017 Sep 7.

The Donnelly Centre, University of Toronto, Toronto, ON M5S 3E1, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada. Electronic address:

SH3 domains are protein modules that mediate protein-protein interactions in many eukaryotic signal transduction pathways. The majority of SH3 domains studied thus far act by binding to proline-rich sequences in partner proteins, but a growing number of studies have revealed alternative recognition mechanisms. We have comprehensively surveyed the specificity landscape of human SH3 domains in an unbiased manner using peptide-phage display and deep sequencing. Based on ∼70,000 unique binding peptides, we obtained 154 specificity profiles for 115 SH3 domains, which reveal that roughly half of the SH3 domains exhibit non-canonical specificities and collectively recognize a wide variety of peptide motifs, most of which were previously unknown. Crystal structures of SH3 domains with two distinct non-canonical specificities revealed novel peptide-binding modes through an extended surface outside of the canonical proline-binding site. Our results constitute a significant contribution toward a complete understanding of the mechanisms underlying SH3-mediated cellular responses.
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http://dx.doi.org/10.1016/j.str.2017.07.017DOI Listing
October 2017

Creation of Phosphotyrosine Superbinders by Directed Evolution of an SH2 Domain.

Methods Mol Biol 2017 ;1555:225-254

Department of Biochemistry and Siebens-Drake Medical Research Institute, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON, Canada, N6A 5C1.

Commercial antibodies raised against phosphotyrosine have been widely used as reagents to detect or isolate tyrosine-phosphorylated proteins from cellular samples. However, these antibodies are costly and are not amenable to in-house production in an academic lab setting. In this chapter, we describe a method to generate super-high affinity SH2 domains, dubbed the phosphotyrosine superbinders, by evolving a natural SH2 domain using the phage display technology. The superbinders are stable and can be easily produced in Escherichia coli in large quantities. The strategy presented here may also be applied to other protein domains to generate domain variants with markedly enhanced affinities for a specific post-translational modification.
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http://dx.doi.org/10.1007/978-1-4939-6762-9_13DOI Listing
February 2018

Repeatedly using the decomposition product of struvite by ultrasound stripping to remove ammonia nitrogen from landfill leachate.

Ultrason Sonochem 2017 Sep 12;38:622-628. Epub 2016 Aug 12.

Hebei Key Laboratory of Applied Chemistry, School of Environmental and Chemical Engineering, Yanshan University, 438 Hebei Avenue, Qinhuangdao 066004, PR China.

In this study, the decomposition of struvite by ultrasound stripping and the recycle use of the decomposition product for the treatment of landfill leachate were investigated. The results indicated that when the decomposition of struvite by ultrasound stripping was performed at 55°C for 40min, the ammonium in the struvite could be almost completely eliminated from the solution system. The characterization analysis showed that magnesium phosphate and the dissolved phosphate ions were the main active derivatives. Approximately 90% of the total ammonia nitrogen (TAN) in landfill leachate can be removed by reusing the decomposition product at pH 9 for 60min. Repeated use of the struvite decomposition product revealed that the TAN removal efficiency decreased with an increase in the number of recycles. However, in the process of multiple recycling, about 90% of TAN removal could be maintained by supplementing a certain amount of the preformed struvite to the solution for every recycle. An economic analysis demonstrated that 79.3% of the treatment cost could be saved by the proposed process compared to the non-recycling process.
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http://dx.doi.org/10.1016/j.ultsonch.2016.08.019DOI Listing
September 2017