International Journal of Polymer Science
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2019
·
IF 1.892
Wei Xiong,Yue-kun Shen,Peng Dong,Ying Xiao,Xiong-qing Huang,Wen-qi Huang,Lu Yang,Xia Feng
Sustained release of anesthesia has shown great promise in the treatment of chronic pain in patients. In this research, we used neutralized ropivacaine as an anesthesia and poly(ε-caprolactone) (PCL) with different architectures to systematically study how these architectures affect the release of ropivacaine. After optimizing the parameters of the preparation of microspheres, ropivacaine-loaded 1-PCL microspheres and 4-PCL microspheres were obtained. Fourier Transform infrared spectra (FT-IR) and X-ray diffraction spectra (XRD) confirmed that ropivacaine was encapsulated within the microsphere rather than inserted on the surface of the microsphere. Ropivacaine was found to be buried deeper in the 1-PCL microsphere than in the 4-PCL microsphere. In vitro release assay revealed that small crystalline grains interfered with ropivacaine release in 4-PCL microspheres during the initial release period, but then two kinds of microspheres showed a similar ropivacaine release rate. We basically proved that the architecture of PCL has a negligible effect on ropivacaine release. Cell proliferation test revealed that the release of products from the microspheres resulted in insignificant toxicity towards mammalian cells.
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Frontiers in Microbiology
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2019
·
IF 4.259
Wu Hao,Guo Ye,Chen Lei,Chen Guiguang,Liang Zhiqun
This study characterized the biosynthetic pathway of the secondary metabolite 1-deoxynojirimycin (DNJ) from Streptomyces lavendulae. The results revealed that glucose was a preferable precursor for DNJ synthesis, and its carbon skeleton underwent a C2-N-C6 cyclization reaction during synthesis. The biosynthetic pathway was related to the glycolysis pathway, and started from fructose-6-phosphate, and involved amination, dephosphorylation, oxidation, cyclization, dehydration, and reduction reaction steps, yielding DNJ. Then, based on clarified biosynthetic pathway information, precursors, analogs, and metabolism inhibitors were used as novel regulators to enhance the production of DNJ. The results demonstrated that the titer of DNJ could reach 296.56 mg/L, which was 3.3-fold higher than that of a control group (90 mg/L) when sodium citrate (0 h, 5 g/L), sorbose (0 h, 1 g/L), iodoacetic acid (20 h, 50 mg/L), and glucose (26 h, 7 g/L) were added during the fermentation process. This study provides a new understanding of the biosynthetic pathway of DNJ, and also provides an efficient strategy to regulate the production of DNJ based on this biosynthetic pathway, which is a new perspective for the regulation of other secondary metabolites.
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RSC Advances
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2018
·Vol. 8
·期 31
·17389-17398
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IF 2.936
Yunquan Zheng,Qisheng Pan,Liuda Mo,Wenyi Zhang,Yunjian Duan,Chengqun Chen,Haijun Chen,Yanghao Guo,Xianai Shi,Jianmin Yang
Alzheimer's disease (AD) is an extremely complex disease, characterized by several pathological features including oxidative stress and amyloid-β (Aβ) aggregation. Blockage of Aβ-induced injury has emerged as a potential therapeutic approach for AD. Our previous efforts resulted in the discovery of Monascus pigment rubropunctatin derivative FZU-H with potential neuroprotective effects. This novel lead compound significantly diminishes toxicity induced by Aβ(1-42) in Neuro-2A cells. Our further mechanism investigation revealed that FZU-H inhibited Aβ(1-42)-induced caspase-3 protein activation and the loss of mitochondrial membrane potential. In addition, treatment of FZU-H was proven to attenuate Aβ(1-42)-induced cell redox imbalance and Tau hyperphosphorylation which caused by okadaic acid in Neuro-2A cells. These results indicated that FZU-H shows promising neuroprotective effects for AD.
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JOURNAL OF WOOD CHEMISTRY AND TECHNOLOGY
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2018
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IF 1.418
Ying Guo,Jian-Qiang Chen,Meng Su,Jian-Guo Hong
Lignocellulosic biomass is regarded as one of the most abundant and sustainable resources for the development of bio-based plastics. The esterification of wood with phthalic anhydride (PA) yields low content due to lack of an efficient modification medium. In the present study, 1-methylimidazole was used as a catalytic medium for the highly efficient esterification of waste lignocellulosic biomass (poplar wood, mulberry wood, and wheat straw) with PA. After modification, the wood particles were plasticized and molded via injection molding. Analyses of the weight percent gain showed that under the same conditions, poplar wood, which has a soft and loose structure, presented the highest extent of esterification, whereas mulberry wood, which has a tight texture, had the lowest extent of esterification. Mulberry wood-based plastics exhibited the best performance in terms of flexural and tensile strength. Notably, short reaction time was favorable to produce bio-based plastics that were light in color. FT-IR spectroscopy and solid-state 13 C NMR spectroscopy confirmed the chemical structures of the esterified products. Dynamic mechanical analysis was used to identify the storage modulus and the damping factor of the esterified products. Analyses of the morphologies of the materials demonstrated different composite structures for the bio-based plastics, which played an important role in their mechanical performance.
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FIBERS AND POLYMERS
·
2018
·Vol. 19
·期 10
·2134-2138
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IF 1.353
Wang Zongqian,Li Changlong,Zhang Hulin,Liu Zhi
Chromophore incorporated into the protein chains through residue modification on silk fibroin will be an important way to get new dyeing technology with improved color fastness. Herein, 1-aminoanthraquinone diazonium salt was prepared and used for the modified dyeing on tyrosine of silk fibroin. The silk after modified dyeing was measured by UV-Vis, FTIR, MS, 1 H-NMR, Data color, and other testing techniques. Interestingly, the resulting silk showed excellent rub and wash fastness. The enhanced color fastness is contributed by an electrophilic substitution reaction between 1- aminoanthraquinone diazonium salt and the ortho position of phenolic hydroxyl in tyrosine molecular. Moreover, the mechanical property of silk was protected effectively by the mild coupling modified dyeing, better than the traditional acid dyeing under high temperature for a long time. This facile strategy provides an alternative approach to silk dyeing and benefits the silk applications.
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BRITISH JOURNAL OF PHARMACOLOGY
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2018
·Vol. 176
·期 3
·416-435
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IF 6.81
Jingyan Li,Junying Huang,Jing Lu,Zhen Guo,Zhuoming Li,Hui Gao,Panxia Wang,Wenwei Luo,Sidong Cai,Yuehuai Hu,Kaiteng Guo,Luping Wang,Zhenzhen Li,Minghui Wang,Xiaolei Zhang,Peiqing Liu
Background and Purpose Activation of PKC-ζ is closely linked to the pathogenesis of cardiac hypertrophy. PKC-ζ can be activated by certain lipid metabolites such as phosphatidylinositol (3,4,5)-trisphosphate and ceramide. However, its endogenous negative regulators are not well defined. Here, the role of the sirtuin1-PKC-ζ signalling axis and the underlying molecular mechanisms were investigated in cardiac hypertrophy. Experimental Approach Cellular hypertrophy in cultures of cardiac myocytes, from neonatal Sprague-Dawley rats, was monitored by measuring cell surface area and the mRNA levels of hypertrophic biomarkers. Interaction between sirtuin1 and PKC-ζ was investigated by co-immunoprecipitation and confocal immunofluorescence microscopy. Sirtuin1 activation was enhanced by resveratrol treatment or Ad-sirtuin1 transfection. A model of cardiac hypertrophy in Sprague-Dawley rats was established by abdominal aortic constriction surgery or induced by isoprenaline in vivo . Key Results Overexpression of PKC-ζ led to cardiac hypertrophy and increased activity of NF-κB, ERK1/2 and ERK5, which was ameliorated by sirtuin1 overexpression. Enhancement of sirtuin1 activity suppressed acetylation of PKC-ζ, hindered its binding to phosphoinositide-dependent kinase 1 and inhibited PKC-ζ phosphorylation in cardiac hypertrophy. Consequently, the downstream pathways of PKC-ζ' were suppressed in cardiac hypertrophy. This regulation loop suggests a new role for sirtuin1 in mediation of cardiac hypertrophy. Conclusions and Implications Sirtuin1 is an endogenous negative regulator for PKC-ζ and mediates its activity via regulating the acetylation and phosphorylation in the pathogenesis of cardiac hypertrophy. Targeting the sirtuin1-PKC-ζ signalling axis may suggest a novel therapeutic approach against cardiac hypertrophy.
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ACS Sustainable Chemistry & Engineering
·
2018
·
IF 6.14
Yufang Wu,Yiwei Sun,Jing Xiao,Xun Wang,Zhong Li
In this work, a novel Gly@HKUST-1 with simultaneously enhanced moisture stability and improved adsorption capacity was developed by grafting glycine (Gly) onto the open metal sites of HKUST-1, in order to recover light hydrocarbons from natural gas efficiently. The resultant Gly@HKUST-1 had higher C2H6 and C3H8 adsorption capacities compared to HKUST-1 and some other metal–organic frameworks, which reached as high as 6.47 and 7.80 mmol/g at ambient conditions. Its C2H6/CH4 and C3H8/CH4 adsorption selectivities were up to 12.6 and 173.5, respectively. Fixed-bed experiments showed that 0.3Gly@HKUST-1 could separate the CH4/C2H6/C3H8 mixtures completely at ambient conditions, showing excellent separation property toward the light hydrocarbons. More importantly, stability experiments confirmed that after the two samples were exposed to moist air (RH of 55%) for 20 days, 0.3Gly@HKUST-1 still remained its crystal structure, while parent HKUST-1 lost most of its crystallinity. Computational simulations showed that Gly grafting onto unsaturated Cu site played a critical role in enhancing stability against water vapor and improving capacity due to its shielding of unsaturated Cu site as well as introduction of −COOH or −NH2 as the H-binding sites. Gly@HKUST-1 is promising for practical application of efficiently recovering ethane and propane from natural gas by adsorption.
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CARBOHYDRATE POLYMERS
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2018
·
IF 5.158
Guoyu Li,Kungang Chai,Liqin Zhou,Zhangfa Tong,Hongbing Ji
A novel aromatic-rich cellulose-urethane polymer (ACUP) was easily fabricated by crosslinking cellulose with 4,4’,4’’-triphenylmethane triisocyanate for preferential adsorption of acetophenone (AP) over 1-phenyethanol (PE). The successful synthesis of ACUP was confirmed by the instrumental analyses, e.g., FTIR, TG, XPS, FE-SEM, 13 C CP/MAS NMR and XRD. For single-solute adsorption of AP or PE onto ACUP, the effects of adsorbent dosage, agitation speed, time, solute concentration and temperature were systematically investigated. The overall adsorption process was exothermal and spontaneous in nature, and followed the pseudo-second-order kinetic rate equation and Freundlich isotherm model. Competitive adsorption studies concerning the effects of phenyl content in ACUP adsorbent, pH and ionic strength were also presented, in which ACUP showed much higher affinity for AP over PE. In addition, ACUP was examined as a column packing material for adsorptive separation of the equimolar mixture of AP-PE, showing excellent separation capability. The easily-regenerated and recyclable features of ACUP were demonstrated by adsorption-desorption cycles in both batch and continuous modes. Furthermore, a possible mechanism for the preferential adsorption of AP over PE, which may be associated with π-π and hydrogen bonding interactions was suggested on the basis of experimental and theoretical results.
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JOURNAL OF CELLULAR PHYSIOLOGY
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2018
·Vol. 234
·期 5
·7161-7173
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IF 3.923
Xuzhao Wang,Yafei Chen,Junwei Li,Shuai Guo,Xiaoe Lin,Hailin Zhang,Yong Zhan,Hailong An
Mortality-to-incidence ratios in patients with cancer are extremely high, positioning cancer as a major cause of death worldwide. Ether-à-go-go-1 (Eag1) is an ion channel that plays important roles in tumour proliferation, malignant transformation, invasion, metastasis, recurrence, and prognosis. Therefore, identifying potent and specific Eag1 channel inhibitors is crucial. In this study, we identified the first natural inhibitor of Eag1, the traditional Chinese medicine agent tetrandrine, and explored the underlying mechanism. Tetrandrine directly interacted with Eag1 and inhibited the currents in a concentration-dependent manner (IC 50 of 69.97 ± 5.2 μM), and the amino acids Ile 550 , Thr 552 , and Gln 557 in the Eag1 C-linker domain were critical for tetrandrine’s inhibitory effect. Moreover, tetrandrine reduced the proliferation of HeLa cells and Chinese hamster ovary (CHO) cells stably expressing Eag1 in a concentration-dependent manner. Finally, tetrandrine (30 mg/kg/day) inhibited tumor growth in mice, demonstrating a 64.21% inhibitory rate of HeLa cell-transplanted tumors. These results suggest that tetrandrine is a potent and selective Eag1 channel inhibitor, and could act as a leading compound in the development of therapies for Eag1 ion channel dysfunction-induced diseases.
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Materials Science & Engineering C-Materials for Biological Applications
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2018
·
IF 5.08
Yiqun Wang,Yi Lu,Jinkang Gong,Yuan Yao
Intermediate filaments, together with actin microfilaments and microtubules constituent the cytoskeleton of mammalian cells, involving in various cellular activities. The roles of intermediate filaments in cell skeleton reorganization when responding with extracellular matrix (ECM) nanostructure are poorly understood yet. To unveil the effects of fibrous composition and orientation on cells, we developed electrospun nanofibers of varying topology and components, and the effects on assembly of intermediate filaments as keratin and vimentin were investigated in detail. We found that aligned nanofibers enhanced expression of E-cadherin and promoted assembly of keratin intermediate filaments. Meanwhile, the compositional variation show different preference on up-regulation of the two intermediate filaments. Compared to keratin, the assembly of vimentin intermediate filaments were promoted by incorporating bovine serum albumin (BSA) functionalized graphene oxide (BSA-GO) into polycaprolactone (PCL) nanofibers. Thus, our findings elucidate how the different physical factors of fibrous extracellular matrix affect the reorganization of cytoskeleton by assembly of keratin and vimentin intermediate filaments.
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INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2019
·
IF 3.375
Yunpeng Hu,Kai Wang,Chunli Han,Tao Wang,Guangsheng Luo
A novel liquid–liquid microdispersion method for the synthesis of TS-1 has been developed by continuous preparation of the precursor. In the novel process, the solution of TBOT in n-hexane could be very uniformly dispersed into the oligomeric silicate prehydrolysis mixture to form microdroplets by a microsieve pore reactor. Due to the fast mixing and very high mass transfer performance of the microdispersion process, the Ti species could be uniformly distributed into the mixture and were more likely to condense into the oligomeric silicate precursor species rather than appear with self-condensation. The prepared samples had a minimum molar ratio of Si/Ti at 51 without extra-framework Ti species. Furthermore, the solvent of n-hexane can be recycled by simple phase separation rather than evaporation under the conditions of using isopropanol, which reduced energy consumption. This continuous microdispersion technology could be controllable and a reliable scaling-up for the preparation of TS-1.
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AUSTRALIAN JOURNAL OF CHEMISTRY
·
2019
·Vol. 72
·期 7
·533-541
·
IF 1.226
Sai Huang,Mei Yang,Xin-Yu Deng,Qian Jiang Zhu,Ying Huang,Zhu Tao,Kai Chen
In the present work, a host–guest system of a hemimethyl-substituted cucurbit[6]uril derived from 3α-methyl-glycoluril (HMeQ[6]) and a hemicyanine dye, trans-4-[4-(dimethylamino)styryl]-1-methylpyridinium iodide (t-DSMI) showing strong fluorescence emission has been evaluated as a fluorescent probe. The results of a preliminary systematic study on the detection of a series of inorganic anions have revealed that this Q[n]-based host–guest fluorescent probe shows clear responses to BF4− and H2PO4− anions through distinct fluorescence quenching. Application of this Q[n]-based host–guest interaction system in anion recognition or detection opens a new avenue in Q[n] chemistry.
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危险品化学品经营许可证（带存储）