Publications by authors named "Weihua Liu"

232 Publications

Comparison of clinical efficacy and safety between dexmedetomidine and propofol among patients undergoing gastrointestinal endoscopy: a meta-analysis.

J Int Med Res 2021 Jul;49(7):3000605211032786

Department of Anesthesiology, Tianjin First Center Hospital, Tianjin, P.R. China.

Objective: To compare the clinical efficacy and safety of dexmedetomidine and propofol in patients who underwent gastrointestinal endoscopy.

Methods: Relevant studies comparing dexmedetomidine and propofol among patients who underwent gastrointestinal endoscopy were retrieved from databases such as PubMed, Embase, and Cochrane Library.

Results: Seven relevant studies (dexmedetomidine group, n = 238; propofol group, n = 239) met the inclusion criteria. There were no significant differences in the induction time (weighted mean difference [WMD] = 3.46, 95% confidence interval [CI] = -0.95-7.88,  = 99%) and recovery time (WMD = 2.74, 95% CI = -2.72-8.19,  = 98%). Subgroup analysis revealed no significant differences in the risks of hypotension (risk ratio [RR] = 0.56, 95% CI = 0.25-1.22) and nausea and vomiting (RR = 1.00, 95% CI = 0.46-2.22) between the drugs, whereas dexmedetomidine carried a lower risk of hypoxia (RR = 0.26, 95% CI = 0.11-0.63) and higher risk of bradycardia (RR = 3.01, 95% CI = 1.38-6.54).

Conclusions: Dexmedetomidine had similar efficacy and safety profiles as propofol in patients undergoing gastrointestinal endoscopy.
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http://dx.doi.org/10.1177/03000605211032786DOI Listing
July 2021

Esophagomediastinal fistula due to secondary esophageal tuberculosis: report of two cases.

J Int Med Res 2021 Jul;49(7):3000605211023696

Department of Gastroenterology, Beijing Friendship Hospital, Capital Medical University, Beijing, China.

Esophageal tuberculosis is rare among digestive system diseases. We herein present two cases of esophageal tuberculosis. One patient presented with a choking sensation and pain in the chest, and the other presented with loss of appetite and emaciation. Both patients had an esophagomediastinal fistula, underwent endoscopic ultrasonography and fine-needle aspiration, were clinically diagnosed with esophageal tuberculosis, received antituberculosis treatment, and exhibited clinical improvement. These two rare cases suggest that the possibility of esophageal tuberculosis should be considered in patients with an esophagomediastinal fistula. Endoscopic ultrasonography and fine-needle aspiration can be performed to assist the diagnosis. Good clinical results can often be achieved with timely antituberculosis treatment.
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http://dx.doi.org/10.1177/03000605211023696DOI Listing
July 2021

Rice Seed Purity Identification Technology Using Hyperspectral Image with LASSO Logistic Regression Model.

Sensors (Basel) 2021 Jun 26;21(13). Epub 2021 Jun 26.

School of Mathematics & Computer Science, Wuhan Polytechnic University, Wuhan 430023, China.

Hyperspectral technology is used to obtain spectral and spatial information of samples simultaneously and demonstrates significant potential for use in seed purity identification. However, it has certain limitations, such as high acquisition cost and massive redundant information. This study integrates the advantages of the sparse feature of the least absolute shrinkage and selection operator (LASSO) algorithm and the classification feature of the logistic regression model (LRM). We propose a hyperspectral rice seed purity identification method based on the LASSO logistic regression model (LLRM). The feasibility of using LLRM for the selection of feature wavelength bands and seed purity identification are discussed using four types of rice seeds as research objects. The results of 13 different adulteration cases revealed that the value of the regularisation parameter was different in each case. The recognition accuracy of LLRM and average recognition accuracy were 91.67-100% and 98.47%, respectively. Furthermore, the recognition accuracy of full-band LRM was 71.60-100%. However, the average recognition accuracy was merely 89.63%. These results indicate that LLRM can select the feature wavelength bands stably and improve the recognition accuracy of rice seeds, demonstrating the feasibility of developing a hyperspectral technology with LLRM for seed purity identification.
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http://dx.doi.org/10.3390/s21134384DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8271842PMC
June 2021

Identification of Resistant Germplasm and Detection of Genes for Resistance to Powdery Mildew and Leaf Rust from 2,978 Wheat Accessions.

Plant Dis 2021 Jun 15. Epub 2021 Jun 15.

Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Center for Agricultural Resources Research, 286 Huaizhong Rd., Shijiazhuang 050021, China, Shijiazhuang, China, 050021;

Powdery mildew and leaf rust, caused by Blumeria graminis f. sp. tritici (Bgt) and Puccinia triticina (Pt), respectively, are widespread diseases of wheat worldwide. Utilizing resistant cultivars is considered as the most economical, environmental-friendly, and effective method to control these diseases. In the present study, a collection of 2,978 wheat accessions consisting of 1,394 advanced breeding lines, 1,078 Chinese cultivars, 291 introduced cultivars, 132 lines containing alien chromosomes, and 83 landraces was tested for reactions to powdery mildew and leaf rust. The results indicated that 659 (22.1%) wheat accessions were highly resistant to a widely prevalent Bgt isolate, E09, at the seedling stage, and 390 were consistently resistant to the mixture of Bgt isolates at the adult-plant stage. Meanwhile, 63 (2.1%) accessions were highly resistant to leaf rust at the adult-plant stage, of which 54 were resistant to a predominant and highly virulent Pt race, THTT, at the seedling stage. Notably, 17 accessions were resistant to both powdery mildew and leaf rust. To detect known genes for resistance to powdery mildew and leaf rust, these accessions were tested with gene-specific or tightly linked markers for seven Pm genes (Pm2, Pm4, Pm5, Pm6, Pm8, Pm21, and Pm24) and ten Lr genes (Lr1, Lr9, Lr10, Lr19, Lr20, Lr24, Lr26, Lr34, Lr37, and Lr46). Of the 659 powdery mildew-resistant accessions, 328 might carry single Pm genes and 191 carry combined Pm genes. Pm2 was detected at the highest frequency of 59.6%, followed by Pm8, Pm6, Pm21, Pm4, and Pm5, while Pm24 was not detected. Besides, 139 accessions might contain unknown Pm genes different from those tested in this study. In the 63 accessions resistant leaf rust, four Lr genes (Lr1, Lr10, Lr26, and Lr34) were detected in 41 accessions either singly or in combination, while six genes (Lr9, Lr19, Lr20, Lr24, Lr37, and Lr46) were not detected. Twenty-two accessions might contain unknown Lr genes different from those tested in this study. This study not only provided important information for rationally distributing resistance genes in wheat breeding programs, but also identified resistant germplasm that might have novel genes to enrich the diversity of resistance sources.
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http://dx.doi.org/10.1094/PDIS-03-21-0532-REDOI Listing
June 2021

A core-shell structured magnetic covalent organic framework as a magnetic solid-phase extraction adsorbent for phenylurea herbicides.

J Chromatogr A 2021 Aug 28;1651:462301. Epub 2021 May 28.

College of Science, Hebei Agricultural University, Baoding 071001, China.

In this work, a core-shell structured magnetic covalent organic framework named as M-TpDAB was constructed with 3,3'-diaminobenzidine (DAB) and 1,3,5-triformylphloroglucinol (Tp) as building units. M-TpDAB was characterized by infrared spectroscopy, nitrogen adsorption-desorption isotherms, powder X-ray diffraction, scanning electron microscopy and transmission electron microscopy. Using the M-TpDAB as adsorbent, a simple and highly effective method was proposed for preconcentrating phenylurea herbicides before high performance liquid-phase chromatography analysis. In the optimized conditions, a good linearity was achieved within the range of 0.15-100 ng mL for water sample, 1.0-100.0 ng mL for tea drink samples. The limits of detection for the analytes were 0.05-0.15 ng mL for water sample and 0.30-0.50 ng mL for drink samples. Satisfactory recoveries of spiked target compounds were in the range of 84.6%-105% for water sample and 80.3%-102% for tea drink samples. Finally, the M-TpDAB based method was successfully used to determine phenylurea herbicides in tea drinks and water samples, demonstrating a good alternative for analyzing trace level of phenylurea herbicides in water samples.
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http://dx.doi.org/10.1016/j.chroma.2021.462301DOI Listing
August 2021

Improving Ammonia Detecting Performance of Polyaniline Decorated rGO Composite Membrane with GO Doping.

Materials (Basel) 2021 May 25;14(11). Epub 2021 May 25.

School of Microelectronics, School of Electronics and Information Engineering, Xi'an Jiaotong University, Xi'an 710049, China.

Gas-sensing performance of graphene-based material has been investigated widely in recent years. Polyaniline (PANI) has been reported as an effective method to improve ammonia gas sensors' response. A gas sensor based on a composite of rGO film and protic acid doped polyaniline (PA-PANI) with GO doping is reported in this work. GO mainly provides NH adsorption sites, and PA-PANI is responsible for charge transfer during the gas-sensing response process. The experimental results indicate that the NH gas response of rGO is enhanced significantly by decorating with PA-PANI. Moreover, a small amount of GO mixed with PA-PANI is beneficial to increase the gas response, which showed an improvement of 262.5% at 25 ppm comparing to no GO mixing in PA-PANI.
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http://dx.doi.org/10.3390/ma14112829DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8198450PMC
May 2021

The role of surgical resection in primary central nervous system lymphoma: a single-center retrospective analysis of 70 patients.

BMC Neurol 2021 May 11;21(1):190. Epub 2021 May 11.

Department of Neurosurgery, Tongji hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095# Jiefang Avenue, Wuhan, 430030, Hubei, China.

Background: The aim of this study was to evaluate the effect of surgical resection and stereotactic biopsy on the complication rate, progression-free survival (PFS) and overall survival (OS) of 70 patients diagnosed at a single institution with primary central nervous system lymphoma (PCNSL) and to explore the predictors of selection for resection and the prognostic factors of PCNSL.

Methods: A retrospective analysis was performed of 70 patients with PCNSL that was diagnosed by surgical resection or stereotactic brain biopsy in our department from January 2013 to May 2019. We divided the patients into two groups: a resection group (n = 28) and a stereotactic biopsy group (n = 42). Data on clinical characteristics, imaging findings, complication rates, PFS and OS were retrospectively reviewed and compared between these two groups. We also analysed the predictors of selection for resection and prognostic factors of PCNSL by multivariate analysis.

Results: The median age was 53.3 ± 14.3 years, and there was a male predominance with a sex ratio of 1.33:1. The most common clinical manifestation was a headache. The complication rate in the resection group was 10.7% versus 7.1% in the stereotactic biopsy group, and there was no statistically significant difference. The rate of improvement in symptoms of the resection group was significantly higher than that of the stereotactic biopsy group. Multivariable analysis identified a single tumour and not involving deep structures as predictors of selection for resection. With a median follow-up of 30 months (range 1-110), the mean OS and PFS of all patients were 16.1 months and 6.2 months, respectively. Patients who underwent surgical resection had a mean OS of 23.4 months and PFS of 8.6 months versus 11.2 months and 4.6 months for those who had a brain biopsy performed. In addition, multivariable analysis showed that not involving deep structures and resection were favourable prognostic factors for PCNSL.

Conclusions: The outcomes of patients with PCNSL treated in our cohort are still poor. In our series, surgical resection might play a role in significantly improving OS and PFS compared with stereotactic biopsy in a subset of patients. The type of surgery and tumour location are prognostic factors for PCNSL.
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http://dx.doi.org/10.1186/s12883-021-02227-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8112018PMC
May 2021

Pattern recognition receptor-initiated innate immune responses in mouse prostatic epithelial cells‡.

Biol Reprod 2021 Jul;105(1):113-127

School of Basic Medicine, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.

Three major pathogenic states of the prostate, including benign prostatic hyperplasia, prostate cancer, and prostatitis, are related to the local inflammation. However, the mechanisms underlying the initiation of prostate inflammation remain largely unknown. Given that the innate immune responses of the tissue-specific cells to microbial infection or autoantigens contribute to local inflammation, this study focused on pattern recognition receptor (PRR)-initiated innate immune responses in mouse prostatic epithelial cells (PECs). Primary mouse PECs abundantly expressed Toll-like receptor 3 (TLR3), TLR4, TLR5, melanoma differentiation-associated protein 5 (MDA5), and IFN-inducible protein 16 (p204 in mouse). These PRRs can be activated by their respective ligands: lipopolysaccharide (LPS) and flagellin of Gram-negative bacteria for TLR4 and TLR5, polyinosinic-polycytidylic acid (poly(I:C)) for TLR3 and MDA5, and herpes simplex virus DNA analog (HSV60) for p204. LPS and flagellin predominantly induced the expression of inflammatory cytokines, including tumor necrosis factor alpha (TNFA), interleukin 6 (IL6), chemokines monocyte chemoattractant protein-1 (MCP1), and C-X-C motif chemokine 10 (CXCL10). Poly(I:C) and HSV60 predominantly induced the expression of type 1 interferons (IFNA and IFNB) and antiviral proteins: Mx GTPase 1, 2',5'-oligoadenylate synthetase 1, and IFN-stimulated gene 15. The replication of mumps virus in PECs was inhibited by type 1 IFN signaling. These findings provide insights into the mechanisms underlying innate immune response in the prostate.
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http://dx.doi.org/10.1093/biolre/ioab076DOI Listing
July 2021

Characterization of an Antiviral Component in Human Seminal Plasma.

Front Immunol 2021 19;12:580454. Epub 2021 Feb 19.

Institute of Basic Medical Sciences, School of Basic Medicine, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China.

Numerous types of viruses have been found in human semen, which raises concerns about the sexual transmission of these viruses. The overall effect of semen on viral infection and transmission have yet to be fully investigated. In the present study, we aimed at the effect of seminal plasma (SP) on viral infection by focusing on the mumps viral (MuV) infection of HeLa cells. MuV efficiently infected HeLa cells . MuV infection was strongly inhibited by the pre-treatment of viruses with SP. SP inhibited MuV infection through the impairment of the virus's attachment to cells. The antiviral activity of SP was resistant to the treatment of SP with boiling water, Proteinase K, RNase A, and DNase I, suggesting that the antiviral factor would not be proteins and nucleic acids. PNGase or PLA2 treatments did not abrogate the antiviral effect of SP against MuV. Further, we showed that the prostatic fluid (PF) showed similar inhibition as SP, whereas the epididymal fluid and seminal vesicle extract did not inhibit MuV infection. Both SP and PF also inhibited MuV infection of other cell types, including another human cervical carcinoma cell line C33a, mouse primary epididymal epithelial cells, and Sertoli cell line 15P1. Moreover, this inhibitory effect was not specific to MuV, as the herpes simplex virus 1, dengue virus 2, and adenovirus 5 infections were also inhibited by SP and PF. Our findings suggest that SP contains a prostate-derived pan-antiviral factor that may limit the sexual transmission of various viruses.
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http://dx.doi.org/10.3389/fimmu.2021.580454DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7933687PMC
June 2021

Up-regulating lncRNA OIP5-AS1 protects neuron injury against cerebral hypoxia-ischemia induced inflammation and oxidative stress in microglia/macrophage through activating CTRP3 via sponging miR-186-5p.

Int Immunopharmacol 2021 Mar 27;92:107339. Epub 2021 Jan 27.

Department of Otolaryngology, The People's Hospital of Linyi, Linyi 276000, Shandong, China. Electronic address:

Background: Inflammation and oxidative stress is closely associated with the development of ischemic brain stroke. Opa-interacting protein 5 antisense RNA 1 (OIP5-AS1), a novel identified long non-coding RNA (lncRNA), has been suggested to play an important role in the development of many types of human cancers. However, the functional involvement of OIP5-AS1 in ischemic stroke is still unknown.

Methods: Quantitative real-time polymerase chain reaction and /or western blot were conducted to determine the expression profiles of OIP5-AS1, C1q/TNF-related protein 3 (CTRP3) and miR-186-5p in the serum of stroke patients, as well as in the ischemic penumbra of rats with middle cerebral artery occlusion/reperfusion (MCAO/R) injury and microglial cells treated with oxygen glucose deprivation/re-oxygenation (OGD/R). Upon selective regulation of OIP5-AS1 and miR-186-5p, the inflammation and oxidative stress responses in microglia/macrophage as well as neurologic functions in MCAO/R rats were detected. Furthermore, the interactions between OIP5-AS1 and miR-186-5p, miR-186-5p and CTRP3 were investigated by RNA immunoprecipitation (RIP) assay, luciferase report assay and bioinformation anaylsis.

Results: We observed markedly increased infarct volume, neuronal apoptosis, inflammation and oxidative stress responses in the infarcted lesions of MCAO/R rats, in line with down-regulated levels of OIP5-AS1 and CTRP3 while up-regulated miR-186-5p. Functional studies demonstrated that up-regulation of OIP5-AS1 attenuated infarct volume, neuronal apoptosis, microglia/macrophage inflammation and oxidative stress responses induced by MCAO/R or OGD/R. In terms of mechanism, we revealed that OIP5-AS1-miR-186-5p-CTRP3 axis played a vital role in modulating microglia/macrophage activation and neuronal apoptosis.

Conclusion: Up-regulating lncRNA OIP5-AS1 protects neuron injury against MCAO/R induced inflammation and oxidative stress in microglia/macrophage through activating CTRP3 via sponging miR-186-5p.
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http://dx.doi.org/10.1016/j.intimp.2020.107339DOI Listing
March 2021

Dietary chlorogenic acid ameliorates oxidative stress and improves endothelial function in diabetic mice via Nrf2 activation.

J Int Med Res 2021 Jan;49(1):300060520985363

Department of Cardiology, The First Affiliated Hospital, Chengdu Medical College, Chengdu, Sichuan, China.

Objectives: Chlorogenic acid (CGA) is an antioxidant dietary factor. We investigated the effects of CGA on endothelial cell dysfunction in diabetic mice and the mechanistic role of nuclear factor erythroid-related factor 2 (Nrf2) in the antioxidant effect of CGA.

Methods: Diabetic (db/db) mice were fed normal chow or chow containing 0.02% CGA for 12 weeks. Human umbilical vein endothelial cells (HUVECs) and mouse aortas were treated with normal or high glucose.

Results: CGA treatment induced upregulation of Nrf2 in HUVECs in a dose-dependent manner. CGA pretreatment prevented reactive oxygen species generation and preserved nitric oxide bioavailability in HUVECs and aortas from wild-type but not Nrf2 mice. CGA improved endothelium-dependent relaxation in high glucose-treated aortas from wild-type and db/db mice, but not Nrf2 mice. Dietary CGA improved endothelium-dependent relaxation in db/db mice.

Conclusions: CGA ameliorates endothelial dysfunction in diabetic mice through activation of the Nrf2 anti-oxidative pathway.
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http://dx.doi.org/10.1177/0300060520985363DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7829538PMC
January 2021

Integrating Lung Parenchyma Segmentation and Nodule Detection with Deep Multi-task Learning.

IEEE J Biomed Health Inform 2021 Jan 20;PP. Epub 2021 Jan 20.

Lung parenchyma segmentation is valuable for improving the performance of lung nodule detection in computed tomography (CT) images. Traditionally, the two tasks are performed separately. This paper proposes a deep multi-task learning (MTL) approach to integrate these tasks for better lung nodule detection. Three new ideas lead to our proposed approach. First, lung parenchyma segmentation is used as the attention module and is combined with nodule detection in a single deep network. Second, lung nodule detection is performed in an anchor-free manner by dividing it into two subtasks, nodule center identification and nodule size regression. Third, a novel pyramid dilated convolution block (PDCB) is proposed to utilize the advantage of dilated convolution and tackle its gridding problem for better lung parenchyma segmentation. Based on these ideas, we design our end-to-end deep network architecture and corresponding MTL method to achieve lung parenchyma segmentation and nodule detection simultaneously. We evaluate the proposed approach on the commonly used Lung Nodule Analysis 2016 (LUNA16) dataset. The experimental results show the value of our contributions and demonstrate that our approach can yield significant improvements compared with state-of-the-art counterparts.
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http://dx.doi.org/10.1109/JBHI.2021.3053023DOI Listing
January 2021

Oriented Proton-Conductive Nanochannels Boosting a Highly Conductive Proton-Exchange Membrane for a Vanadium Redox Flow Battery.

ACS Appl Mater Interfaces 2021 Jan 12;13(3):4051-4061. Epub 2021 Jan 12.

Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China.

In this work, we propose a sulfonated poly (ether ether ketone) (SPEEK) composite proton-conductive membrane based on a 3-(1-hydro-imidazolium-3-yl)-propane-1-sulfonate (Him-pS) additive to break through the trade-off between conductivity and selectivity of a vanadium redox flow battery (VRFB). Specifically, Him-pS enables an oriented distribution of the SPEEK matrix to construct highly conductive proton nanochannels throughout the membrane arising from the noncovalent interaction. Moreover, the "acid-base pair" effect from an imidazolium group and a sulfonic group further facilitates the proton transport through the nanochannels. Meanwhile, the structure of the acid-base pair is further confirmed based on density functional theory calculations. Material and electrochemical characterizations indicate that the nanochannels with a size of 16.5 nm are vertically distributed across the membrane, which not only accelerate proton conductivity (31.54 mS cm) but also enhance the vanadium-ion selectivity (39.9 × 10 S min cm). Benefiting from such oriented proton-conductive nanochannels in the membrane, the cell delivers an excellent Coulombic efficiency (CE, ≈ 98.8%) and energy efficiency (EE, ≈ 78.5%) at 300 mA cm. More significantly, the cell maintains a stable energy efficiency over 600 charge-discharge cycles with only a 5.18% decay. Accordingly, this work provides a promising fabrication strategy for a high-performance membrane of VRFB.
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http://dx.doi.org/10.1021/acsami.0c20847DOI Listing
January 2021

Benzoxazine Porous Organic Polymer as an Efficient Solid-Phase Extraction Adsorbent for the Enrichment of Chlorophenols from Water and Honey Samples.

J Chromatogr Sci 2021 Mar;59(4):396-404

Department of Chemistry, College of Science, Hebei Agricultural University, 289 Lingyusi Street, Baoding 071001, China.

Porous organic polymers have gained great research interest in the field of adsorption. A benzoxazine porous organic polymer (BoxPOP) constructed from p-phenylenediamine, 1,3,5-trihydroxybenzene and paraformaldehyde was fabricated and explored as an adsorbent for solid-phase extraction (SPE) of four chlorophenols from water and honey samples. Under the optimized SPE conditions, the response linearity for the analysis of the SPE extract of the chlorophenols by high performance liquid chromatography-diode array detector was observed in the range of 0.2-40.0 ng mL-1 for water samples and 5.0-400.0 ng g-1 for honey samples. The method detection limits of the analytes were 0.06-0.08 ng mL-1 for water samples and 1.5-2.0 ng g-1 for honey samples. The recoveries of the analytes from fortified water and honey samples ranged from 84.8 to 119.0% with the relative standard deviations below 8.4%. The results indicate that the prepared BoxPOP is an effective adsorbent for the chlorophenols. The established method provides an alternative approach for the determination of chlorophenols in real samples.
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http://dx.doi.org/10.1093/chromsci/bmaa106DOI Listing
March 2021

Graphene oxide/graphene hybrid film with ultrahigh ammonia sensing performance.

Nanotechnology 2021 Mar;32(11):115501

Department of Microelectronics, School of Electronic and Information Engineering, Xi'an Jiaotong University, Xi'an 710049, People's Republic of China.

In this paper, a novel ammonia detection hybrid film is proposed based on a graphene oxide (GO)/graphene stack, which shows excellent sensing characteristics at room temperature. It is attributed to the cooperation of GO layer serving as molecular capture layer while graphene serving as conductive layer. GO layer is obtained on chemical vapor deposited graphene film by a simple drop-casting method. The prepared GO/graphene hybrid film is directly transferred to the target substrate without any additional transfer vehicle to reduce possible contamination. The success of the transfer depends on the mechanical strength of GO layer. The thickness of GO layer can scale down to 55 nm while sustaining the transfer process. The best ammonia gas sensing performance is obtained at about 275 nm GO layer thickness and the ammonia detection limit is calculated to be 1.5 ppb. In conclusion, the ammonia gas sensing performance of GO/graphene hybrid film can be significantly improved through GO layer thickness optimization.
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http://dx.doi.org/10.1088/1361-6528/abd05aDOI Listing
March 2021

Low-Power pH Sensor Based on Narrow Channel Open-Gated AlGaN/GaN HEMT and Package Integrated Polydimethylsiloxane Microchannels.

Materials (Basel) 2020 Nov 22;13(22). Epub 2020 Nov 22.

School of Microelectronics, Xi'an Jiaotong University, Xi'an 710049, China.

pH sensors with low-power and strong anti-interference are extremely important for industrial online real-time detection. Herein, a narrow channel pH sensor based on AlGaN/GaN high electron mobility transistor (HEMT) with package integrated Polydimethylsiloxane (PDMS) microchannels is proposed. The fabricated device has shown potential advantages in improving stability and reducing power consumption in response to pH changes of the solution. The performance of the pH sensor was demonstrated where the preliminary results showed an ultra-low power (<5.0 μW) at = 1.0 V. Meanwhile, the sensitivity was 0.06 μA/V·pH in the range of pH = 2 to pH = 10, and the resolution of the sensor was 0.1 pH. The improvement in performance of the proposed sensor can be related to the narrow channel and microchannel, which can be attributed to better surface GaO in a microchannel with larger H and HO concentration on the sensing surface during the detection process. The low-power sensor with excellent stability can be widely used in various unattended or harsh environments, and it is more conducive to integration and intelligence, which lays the foundation for online monitoring in vivo.
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http://dx.doi.org/10.3390/ma13225282DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7700280PMC
November 2020

Raman and XRD study of CO sorption and desorption in air by a NaSiO-NaCO hybrid sorbent.

Phys Chem Chem Phys 2020 Dec;22(46):27263-27271

Shanghai Institute of Applied Physics, Chinese Academy of Sciences, P. O. Box 800-204, Shanghai 201800, China.

Silicate-carbonate mixtures as new CO2 capture agents have the latent application potential. CO2 sorption or desorption processes using the Na4SiO4-Na2CO3 mixture sorbent in air were analyzed by in situ Raman spectroscopy and X-ray diffraction from 25 °C to 900 °C. The results show that the Na4SiO4-Na2CO3 mixture sorbent could continuously absorb and strip CO2 by thermal swinging. The CO2 sorption was produced via a two-step process depending on the temperature range. Initially, CO2 dissolved in carbonate to produce pyrocarbonate (C2O52-) ions, which subsequently reacted with SiO44- anion to produce the polymer silicates and CO32- anion. The C2O52- anion on the surface of the silicates promoted CO2 transformation to CO32- anion through the reaction with SiO44- anions. The CO32- anion decomposed the polymer silicates to produce orthosilicates and CO2 gas again at high temperature. By this circulation, CO2 could dissolve in carbonate more easily and be absorbed and stripped continuously by thermal swinging in the mixture sorbent than the pure carbonate. The processes of recovering heat and separating CO2 from flue gas simultaneously without decreasing the temperature is an economical and attractive method for energy conservation. It offers the theoretical basis for developing new heat-storage and CO2-capture technology.
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http://dx.doi.org/10.1039/d0cp04335dDOI Listing
December 2020

Blood coagulation factor VIII D1241E polymorphism leads to a weak malectin interaction and reduction of factor VIII posttranslational modification and secretion.

Exp Cell Res 2020 12 2;397(1):112334. Epub 2020 Nov 2.

Shaanxi Yida Haemophilia Institute, China.

Blood coagulation factor VIII (FVIII) is a key cofactor in regulation of blood coagulation. This study investigated the mechanism by which FVIII is translated and transported into the endoplasmic reticulum (ER) and processed in the Golgi apparatus before secretion using an in vitro cell model. HEK-293T cells were transfected with vectors carrying wild-type (WT) FVIII or polymorphic FVIII D1241E for coexpression with ER lectins and treatment with tunicamycin (an N-linked glycosylation inhibitor), 1-deoxynojirimycin (an alpha-glucosidase inhibitor), endoglycosidase H, or MG132 (Cbz-Leu-Leu-leucinal; a proteasome inhibitor). The data showed that the minor allele of FVIII D1241E was able to reduce FVIII secretion into the conditioned medium but maintain a normal level of procoagulation ability, although both FVIII WT and the minor allele of FVIII D1241E showed similar levels of transcription and translation capacities. Functionally, the D1241E polymorphism led to a reduced level of FVIII in the Golgi apparatus because of its reduced association with malectin, which interacts with newly synthesized glycoproteins in the ER for FVIII folding and trafficking, leading to degradation of the minor allele of FVIII D1241E in the cytosol. This study demonstrated that malectin is important for regulation of the FVIII posttranslational process and that the minor allele of FVIII D1241E had a reduced association with malectin but an increased capacity for proteasomal FVIII degradation. These data imply the role of the ER quality control in future recombinant FVIII development.
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http://dx.doi.org/10.1016/j.yexcr.2020.112334DOI Listing
December 2020

Evaluation of synergistic effect from Ag-AgClBrI composite on photocatalytic degradation the oil field pollutants.

Spectrochim Acta A Mol Biomol Spectrosc 2021 Feb 4;247:119029. Epub 2020 Oct 4.

National and Local Joint Engineering Research Center of Shale Gas Exploration and Development, Chongqing 401120, China; Institute of Geology and Mineral Resources, Chongqing 401120, China.

A series of Ag/AgX (X = Cl, Br, I; X = Cl, Br, or X = Cl, I, or X = Br, I; X = Cl, Br, and I) composite photocatalysts were synthesized via a facile photoreduction. The several characterization methods of X-ray diffraction (XRD), energy dispersive X-ray spectrometry (EDS) mapping and X-ray photoelectron spectroscopy (XPS) were characterized the samples. Through evaluation the photocatalytic activity of degradation rhodamine, methyl orange, and phenol, Ag-AgClBrI exhibited the superior selective photocatalytic activities than other photocatalysts. The reason for improved photocatalytic property of Ag-AgClBrI was attributed to the multifarious halogen atoms with the synergistic effect and the surface plasmon resonance (SPR) effect of Ag. Furthermore, the recycle experiments were conducted to reveal the stability and reusability, the trapping experiments confirmed the active species of Ag-AgClBrI.
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http://dx.doi.org/10.1016/j.saa.2020.119029DOI Listing
February 2021

SFRP5 mediates downregulation of the wnt5a/caveolin-1/JNK signaling pathway.

J Endocrinol 2020 12;247(3):263-272

Department of Pediatrics, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, China.

This study investigated the effects of Wnt5a/caveolin/JNK signaling pathway and SFRP5 protein on ox-LDL-induced apoptosis of HUVEC cells. The difference of serological indexes between healthy average weight and obese children and the expression of Wnt 5a and SFRP5 was detected by clinical examination, and the correlation between serum SFRP5, Wnt 5a and the vascular endothelial injury was detected. HUVEC cells were induced by ox-LDL to construct an endothelial injury model, siRNA-transfected cells were used to construct downregulated SFRP5 and Wnt 5a expression groups, and recombination methods were used to construct upregulated Wnt5a and SFRP5 expression groups. The expression of Wnt 5a, caveolin-1, JNK and apoptosis-related proteins under different treatments were detected by the Western blot method, and apoptosis was detected by flow cytometry. Serological results showed that the level of Sfrp5 in obese children was significantly lower than that in healthy children, and the level of Wnt5a was significantly higher than that in healthy children. Moreover, Ln Sfrp5 was significantly negatively correlated with Ang-2 in blood circulation, ICAM-1 and E-selectin selectin, but not with VCAM-1. When Wnt5a was upregulated, the expression of caveolin-1 and JNK increased significantly, Bcl-2 decreased significantly, and the apoptotic rate increased significantly. Nevertheless, when Sfrp5 expression was upregulated, the result was the opposite. SFRP5 and Wnt5a are involved in the vascular endothelial injury. Wnt5a can promote apoptosis of HUVEC cells through Wnt5a/JNK/Caveolin-1 pathway, while SFRP5 can inhibit apoptosis by interfering with this pathway.
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http://dx.doi.org/10.1530/JOE-20-0328DOI Listing
December 2020

Rab27a deletion impairs the therapeutic potential of endothelial progenitor cells for myocardial infarction.

Mol Cell Biochem 2021 Feb 23;476(2):797-807. Epub 2020 Oct 23.

Guangzhou Institute of Cardiovascular Disease, Guangdong Key Laboratory of Vascular Diseases, State Key Laboratory of Respiratory Disease, the Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong, 510260, People's Republic of China.

Endothelial progenitor cell (EPC) transplantation has shown advantages in the treatment of myocardial infarction (MI) in animal models and clinical trials through mechanisms of direct intercellular contacts, autocrine, and paracrine. However, the effects of EPC transplantation for MI treatment remain controversial and the underlying mechanisms have not been fully elucidated. Here, we explored the role of Rab27a in the therapeutic potential of EPC transplantation in MI. We found that Rab27a knockout impaired the viability, and reduced the proliferation and tube formation function of ECPs. The recovery of cardiac function and improvement of ventricular remodeling from EPCs transplantation were significantly damaged by Rab27a deletion in vivo. Rab27a deletion inhibited the protein expression of phosphoinositide 3-kinase (PI3K) and cyclin D1 and the phosphorylation levels of Akt and FoxO3a. Therefore, Rab27a knockout suppressed the PI3K-Akt-FoxO3a/cyclin D1 signaling pathway. Furthermore, Rab27a ablation dramatically reduced exosome release in EPCs. These results demonstrated that Rab27a plays an essential role in EPC functions. The elucidation of this mechanism provides novel insights into EPC transplantation as a promising treatment for post-MI injuries.
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http://dx.doi.org/10.1007/s11010-020-03945-xDOI Listing
February 2021

Copeptin and Nesfatin-1 Are Interrelated Biomarkers with Roles in the Pathogenesis of Insulin Resistance in Chinese Children with Obesity.

Ann Nutr Metab 2020 7;76(4):223-232. Epub 2020 Oct 7.

Department of Pediatrics, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China,

Background: Copeptin and nesfatin-1 have recently been identified as novel peptides that play a role in the pathogenesis of obesity-related insulin resistance in adults. However, the relationship between them has not yet been elucidated, and their circulating levels in children with obesity have not been adequately studied. Therefore, the current study aimed to investigate whether their levels are altered in Chinese children with obesity, as well as to determine the correlation of these 2 peptides with each other, with insulin resistance, and with other biochemical parameters.

Methods: A total of 156 children were enrolled in this study, including 101 children with obesity and 55 lean controls. Anthropometric parameters and clinical data of all subjects were collected, and circulating tumor necrosis factor-α, adiponectin, leptin, copeptin, and nesfatin-1 levels were measured using ELISA.

Results: Serum copeptin and nesfatin-1 levels were significantly elevated in children with obesity and children with insulin resistance compared to control subjects. In addition, nesfatin-1 and copeptin levels were found to be significantly positively correlated with one another by Pearson's correlation and partial correlation. In multiple regression analysis using nesfatin-1 or copeptin as the dependent parameter, a significant correlation was observed between nesfatin-1 and copeptin, and associations between each of them with homeostasis model assessment of insulin resistance (HOMA-IR) were detected.

Conclusion: These novel findings shed light on the possible interplay role of these 2 molecules in obesity-related insulin resistance.
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http://dx.doi.org/10.1159/000508883DOI Listing
October 2020

Associations of multiple serum biomarkers and the risk of cardiovascular disease in China.

BMC Cardiovasc Disord 2020 09 29;20(1):426. Epub 2020 Sep 29.

Shandong First Medical University (Shandong Academy of Medical Sciences), 169 Great Wall Rd, Taian, 271000, Shandong, China.

Background: Previous studies focus on one or several serum biomarkers and the risk of cardiovascular disease (CVD). This study aims to investigate the association of multiple serum biomarkers and the risk of CVD and evaluate the dose-relationship between a single serum metabolite and CVD.

Methods: Our case-control study included 161 CVD and 160 non-CVD patients who had a physical examination in the same hospital. We used stratified analysis and cubic restricted analysis to investigate the dose-response relationship of individual serum biomarkers and the CVD incident. Moreover, to investigate serum biomarkers and CVD, we used elastic net regression and logistic regression to build a multi-biomarker model.

Results: In a single serum biomarker model, we found serum FT4, T4. GLU, CREA, TG and LDL-c were positively associated with CVD. In the male group, serum T4, GLU and LDL-c were positively associated with CVD; and serum TG was positively associated with CVD in the female group. When patients ≤63 years old, serum T4, GLU, CREA and TG were positively associated with CVD, and serum TG and LDL-c were positively associated with CVD when patients > 63 years old. Moreover, serum GLU had nonlinearity relationship with CVD and serum TG and LDL-c had linearity association with CVD. Furthermore, we used elastic regression selecting 5 serum biomarkers (GLU, FT4, TG, HDL-c, LDL-c) which were independently associated with CVD incident and built multi-biomarker model. And the multi-biomarker model had much better sensitivity than single biomarker model.

Conclusion: The multi-biomarker model had much higher sensitivity than a single biomarker model for the prediction of CVD. Serum FT4, TG and LDL-c were positively associated with the risk of CVD in single and multiple serum biomarkers models, and serum TG and LDL-c had linearity relationship with CVD.
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http://dx.doi.org/10.1186/s12872-020-01696-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7523396PMC
September 2020

Risk perception, knowledge, information sources and emotional states among COVID-19 patients in Wuhan, China.

Nurs Outlook 2021 Jan-Feb;69(1):13-21. Epub 2020 Aug 22.

Shandong First Medical University & Shandong Academy of Medical Sciences, Taian, Shandong, PR China; Department of Nursing, Sir Run Run Hospital of Nanjing Medical University, Nanjing, Jiangsu, PR China. Electronic address:

Background: The rapidly evolving COVID-19 pandemic has become a global health crisis. Several factors influencing risk perception have been identified, including knowledge of the disease, information sources, and emotional states. Prior studies on COVID-19-related risk perception primarily focused on the general public, with little data available on COVID-19 patients.

Purpose: To investigate COVID-19 patients' risk perception, knowledge of the disease, information sources, and emotional states in the epicenter, Wuhan, during the COVID-19 outbreak in China.

Methods: Data were collected online using self-administered electronic questionnaire developed with reference to previous relevant studies and publications by the World Health Organization.

Findings: A higher level of perceived risk was found in relation to COVID-19 as compared to other potential health threats. Knowledge gaps existed regarding transmission and prevention of COVID-19. Additionally, risk perception was negatively related to knowledge and positively related to depressive states. Moreover, social media was a primary source for COVID-19 information, whereas the most trusted sources were health professionals.

Discussion: Realistic perception of risk should be encouraged considering both physical and mental health while developing relevant strategies. Furthermore, risk communication needs to be specifically tailored for various target groups, such as the elderly and mentally vulnerable individuals, with the adoption of popular media platforms.
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http://dx.doi.org/10.1016/j.outlook.2020.08.005DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7442898PMC
January 2021

A comparison of the efficacy, safety, and duration of frame-based and Remebot robot-assisted frameless stereotactic biopsy.

Br J Neurosurg 2021 Jun 17;35(3):319-323. Epub 2020 Sep 17.

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

Objective: The aim of this study was to compare the efficacy, safety, and duration of Remebot robot-assisted frameless brain biopsy with those of standard frame-based stereotactic biopsy.

Patients And Methods: A retrospective analysis of 66 patients undergoing stereotactic brain biopsy in our department from January 2015 to January 2019 was performed. We divided the patients into two groups: the frame-based group ( = 35) and the Remebot robot group ( = 31). Data on clinical characteristics, total procedure length, overall discomfort, diagnostic yield, complications, and postoperative length of hospital stay were retrospectively reviewed and compared between these two groups.

Results: No significant difference in diagnostic yield was detected in the two groups, with frame-based biopsy having a diagnostic yield of 91.4% and Remebot robot-assisted frameless brain biopsy having a diagnostic yield of 93.5%. The duration of the total procedure was 116.5 min for the frame-based biopsy and 80.1 min for the Remebot robot-assisted frameless brain biopsy ( < 0.001). There were no statistically significant differences in complication rate or postoperative duration of hospitalization between the two groups. The overall patient discomfort in the frame-based group was significantly greater than that in the Remebot robot group (visual analog scale score 2.7 ± 1.2 versus 1.5 ± 0.7,  = 0.001).

Conclusions: Remebot robot-assisted frameless brain biopsy was as efficacious and safe as standard stereotactic frame-based biopsy. However, frameless biopsy can alleviate the suffering of the patient and reduce the total duration of the procedure. Remebot robot-assisted frameless brain biopsy is easy to use and better accepted by patients than frame-based biopsy.
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http://dx.doi.org/10.1080/02688697.2020.1812519DOI Listing
June 2021

Flat-shaped posterior cranial fossa was associated with poor outcomes of microvascular decompression for primary hemifacial spasm.

Acta Neurochir (Wien) 2020 11 15;162(11):2801-2809. Epub 2020 Sep 15.

Department of Neurosurgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei Province, People's Republic of China.

Background: Numerous factors have been investigated on affecting the outcomes of primary hemifacial spasm (HFS) after microvascular decompression (MVD). It is well established that anatomical differences of the posterior cranial fossa (PCF) plays an important role in the occurrence of HFS. However, it is still not clear whether morphological characteristics of PCF affect the surgical outcomes of HFS after MVD. Our study aims to investigate the prognostic factors for surgical outcomes of MVD for primary HFS, with a particular focus on the morphological characteristics of PCF.

Methods: Between January 2014 and November 2017, a total of 152 HFS patients who underwent MVD treatment in our department were included in this study. The clinical data were retrospectively reviewed. The outcomes of MVD were classified into success and failure groups according to the short- and long-term postoperative responses. Particularly, we established an ellipsoid model for PCF. The related length (Y), width (X) and height (Z) of the PCF were measured and the volume of PCF was calculated employing a formula of [Formula: see text]XYZ. The relationship between PCF volume and surgical outcomes was statistically analysed.

Results: The severity of neurovascular compression (NVC) (p = 0.010), type of NVC (p = 0.001) and lateral spread response (LSR) (p < 0.0001) significantly influenced the long-term surgical outcomes of MVD for primary HFS. In particular, for the first time, we demonstrated that a flat-shaped PCF was associated with poor long-term outcome and postoperative recurrence.

Conclusions: Our current study suggests that mild NVC, small vessel compression, intraoperative LSR persistence and flat-shaped PCF are independent factors predicting poor prognosis of MVD for primary HFS.
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http://dx.doi.org/10.1007/s00701-020-04547-8DOI Listing
November 2020

Prognostic significance of ARL9 and its methylation in low-grade glioma.

Genomics 2020 11 1;112(6):4808-4816. Epub 2020 Sep 1.

Department of Neurosurgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China. Electronic address:

This study aimed to determine the value of ARL9 expression or methylation as a biomarker for LGG survival. We investigated the expression, methylation, prognosis and immune significance of ARL9 through bioinformatics analysis. ARL9 is negatively regulated by ARL9 methylation, leading to its low expression in LGG tissues. Both low ARL9 expression and hypermethylation predicted favorable OS and PFS in LGG patients, according to the TCGA database. Cox regression demonstrated that low ARL9 expression and ARL9 hypermethylation were independent biomarkers for OS. Moreover, three other glioma databases were utilized to verify the prognostic role of ARL9 in LGG, and the similar results were reached. A meta-analysis revealed that low ARL9 expression was closely relevant to better OS. Finally, ARL9 expression exhibited a close correlation with some immune cells, especially CD8+ T cells. ARL9 could constitute a promising prognostic biomarker, and probably plays an important role in immune cell infiltration in LGG.
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http://dx.doi.org/10.1016/j.ygeno.2020.08.035DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7462573PMC
November 2020

Combination of magnetic solid-phase extraction and HPLC-UV for simultaneous determination of four phthalate esters in plastic bottled juice.

Food Chem 2021 Mar 17;339:127855. Epub 2020 Aug 17.

College of Science, Hebei Agricultural University, Baoding 071001, China. Electronic address:

A magnetic o-hydroxyazobenzene (M-HAzo) porous organic polymer was facilely prepared by a green azo coupling reaction in aqueous solution. The prepared M-HAzo was applied as a new adsorbent for the first time to pre-concentrate phthalate esters (PAEs) from plastic bottled juice, followed by their determination with high performance liquid chromatography-ultraviolet detection. The effects of various parameters, i.e., the mass ratio of the [email protected] to HAzo, extraction time, ionic strength, pH of the sample, desorption conditions were optimized. Under the optimized conditions, the M-HAzo based method exhibited good performance in terms of linear range (0.3-50.0 μg L), detection limit (0.08-0.50 μg L), accuracy (recovery of 78.0-115.0%) and repeatability (relative standard deviation of 2.9-7.8%). This work provides a sensitive method for analysis of PAEs at trace levels in drinks, which is featured with high sensitivity, simple operation and environmentally-friendly merit and will have a promising potential in analysis of other organic pollutants.
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http://dx.doi.org/10.1016/j.foodchem.2020.127855DOI Listing
March 2021

Graphene intercalated with carbon nanosphere: a novel solid-phase extraction sorbent for five carbamate pesticides.

Mikrochim Acta 2020 08 27;187(9):521. Epub 2020 Aug 27.

College of Science, Hebei Agricultural University, Baoding, 071001, China.

Graphene-carbon nanosphere composite ([email protected]) was prepared via a simple hydrothermal method. The [email protected] nanocomposite was characterized by X-ray diffraction, scanning electron microscope, surface area, and porosity analysis. The [email protected] was applied as a new sorbent for solid-phase extraction of five carbamate pesticides (tsumacide, carbaryl, isoprocarb, bassa, diethofencarb) prior to quantitative determination by high-performance liquid chromatography with ultraviolet detection at 208 nm. Some experimental parameters including desorption conditions, sample pH, sample volume, and loading rate were studied carefully. Under the optimized condition, the method provided good linearity ranging from 0.3 to 100.0 ng mL with low limits of detection of 0.10-0.20 ng mL for grape juice, 0.10-0.30 ng mL for blend fruit juice, and 0.10-0.20 ng mL for water sample. Good method recoveries (80.2-110%) with relative standard deviations less than 7.2% and high enrichment factors (167-293) were achieved. Results demonstrated that this novel [email protected] can serve as a promising alternative sorbent for more applications. In this work, a graphene-carbon nanosphere ([email protected]) composite was synthesized via a simple hydrothermal method. Then, the [email protected] was served as a novel sorbent for solid-phase extraction of five carbamate pesticides (tsumacide, carbaryl, isoprocarb, bassa, diethofencarb) in juice and environmental water samples, followed by their quantitative analysis with high-performance liquid chromatography-ultraviolet detection.
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http://dx.doi.org/10.1007/s00604-020-04497-zDOI Listing
August 2020

Preparation of phenylboronic acid based hypercrosslinked polymers for effective adsorption of chlorophenols.

J Chromatogr A 2020 Sep 8;1628:461470. Epub 2020 Aug 8.

Department of Chemistry, College of Science, Hebei Agricultural University, Baoding 071001, Hebei, China; College of Food Science and Technology, Hebei Agricultural University, Baoding 071001, Hebei, China. Electronic address:

Hypercrosslinked polymers (HCPs) have demonstrated effective adsorption capabilities because of their rich porosity and high specific surface area. However, the HCPs prepared with phenylboronic acid based compounds as monomers via Friedel-Crafts alkylation reaction have not been reported yet. Herein, four new HCPs with phenylboronic acid (PBA), 1,4-benzenediboronic acid, 4-hydroxyphenylboronic acid and 4-carboxyphenylboronic acid as the respective monomers were prepared for the first time. Their Brunner-Emmet-Teller surface areas were 909.1 m g, 71.9 m g, 39.8 m g and 29.3 m g, respectively. The prepared HCP with PBA as the monomer (named as PBA-HCP) displayed the best adsorption capability for chlorophenols. Then, it was investigated as a SPE adsorbent for the extraction of some chlorophenols from water and honey-pomelo beverage samples prior to high performance liquid-phase chromatography with diode array detection. The established method had low limits of detection for the analytes in the range from 0.06 to 0.2 ng mL for water samples and from 0.3 to 1.0 ng mL for honey-pomelo beverage samples. The linear response for the analytes was in the range of 0.18-100.0 ng mL for water samples and 0.9-100.0 ng mL for honey-pomelo beverage samples. The method also had a good repeatability with the relative standard deviations less than 7.1% and a fairly good accuracy with the method recoveries falling between 80.0% and 120.0%. The adsorption capacities of the PBA-HCP for 2-chlorophenol, 3-chlorophenol, 2,3-dichlorophenol and 2,4-dichlorophenol were 21.7 mg g, 31.2 mg g, 77.1 mg g and 82.1 mg g, respectively. The PBA-HCP also exhibited excellent extraction capabilities for some other compounds, especially for those that have more hydrogen bonding sites.
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http://dx.doi.org/10.1016/j.chroma.2020.461470DOI Listing
September 2020
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