JOURNAL OF APPLIED POLYMER SCIENCE
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2012
·
IF 1.289
Di Zhao,JianFeng Xu,Lu Wang,JianJia Du,KeDong Dong,CaiFei Wang,XiangDong Liu
Two phosphorylated chitosan derivatives with a similar degree of substitution of about 0.5 were synthesized via either the esterification of chitosan's hydroxyl groups by P 2 O 5 in methanesulfonic acid or the selective incorporation of methylene phosphonic groups on chitosan's amino groups by formaldehyde/H 3 PO 3 in water. The performances of the resulting O -phosphorylated chitosan (OPC) and N -methylene phosphonic chitosan (NMPC) as amphoteric flocculants were assessed in comparison with that of unmodified chitosan. In turbidity removal experiments using kaolin suspensions in water, OPC removed about 90% turbidity, but NMPC only removed 60%. The lower flocculation efficiency of NMPC was attributed to the decreased acid strength of the N -methylene phosphate groups in NMPC. These results revealed that the acidity of the phosphate groups introduced in the modified chitosans is an important factor with regard to the flocculation efficiency, and consequently that O-phosphorylation is more suitable than N-phosphorylation for preparing chitosan-based amphoteric flocculants. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
研究领域:
材料科学
·
环境科学
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DOI
高影响因子
Biology Direct
·
2025
·Vol. 20
·期 1
·1-15
·
IF 4.9
Wei Xiaoyong,Zou Long,Huang Yanqing,Qiu Chuan,Cheng Guang,Chen Ye,Rao Jun
Background Hepatocellular carcinoma (HCC) is among the deadliest cancers globally. Yes-Associated Protein (YAP), a Hippo pathway effector, crucially regulates cell proliferation and apoptosis. Recent research has implicated YAP’s role in HCC progression, but the mechanisms are unclear. This study aims to clarify YAP’s function in HCC, emphasizing its regulation of key pathways and targets. Results Gene knockout and overexpression models were established in nude mice and cell lines of HCC cells to investigate YAP’s impact on tumorigenesis. Additionally, functional assays and molecular biology techniques were employed to identify YAP’s regulatory networks. The study demonstrates that LDHA-regulated lactate production promotes YAP activation and malignant phenotypes in HCC. Overexpression of LDHA in HepG2 and Huh7 cells increased lactate levels and activated the YAP pathway, enhancing cell proliferation, migration, and invasion. Lactate treatment also promoted these malignant phenotypes by inhibiting YAP phosphorylation at Ser127. In a xenograft model, lactate accelerated tumor growth through YAP activation. YAP lactylation at K102 antagonized its Ser127 phosphorylation, further promoting malignant progression. Conclusions This study highlights the significance of YAP in HCC pathogenesis, providing insights into potential therapeutic targets for HCC management. Graphical
研究领域:
肿瘤学
·
分子生物学
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产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
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2023
·
IF 8.8
Yanfei Xu,Changwei He,Zheng Zhou
The gelation of walnut protein isolates has not been extensively studied, mainly due to their inherent poor dispersity. This study investigated the gelation of alkaline-extracted walnut protein isolates (AWPI) and phosphorylated walnut protein isolates (PWPI) induced by heat treatment with glucono-δ-lactone (GDL) acidification, focusing on the impact of GDL concentrations on microstructure, rheology, and texture of the resulting gels. The PWPI gel exhibited lower hardness but a smoother structure than the AWPI gel. Notably, acidification with GDL (0.6–1.2%) significantly increased the stiffness of PWPI gels, increasing storage modulus and yield stress 10–50 times, while weakening AWPI gels. Varying concentrations of GDL effectively modulated the microstructure of the PWPI gels, leading to the altered texture (from a soft-solid state to a well-self-supporting stiff-solid gel) and water holding capacity (from approximately 46% to 85%). Additionally, hydrophobic interactions and disulfide bonds were identified as the primary forces involved in the gels.
研究领域:
食品科学
·
蛋白质化学
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产品关联
DOI
PubMed
高影响因子
JOM
·
2022
·Vol. 75
·期 4
·1019-1033
·
IF 2.597
Luo Yinbo,He Dongfeng,Zhao Hongbo
Indirect mineral carbonation is considered an ideal CO 2 sequestration strategy because of its high carbonation rate and high value-added products. This research explores the carbonation ability of different carbon species—CO 3 2– ions, HCO 3 – ions, and H 2 CO 3 —in their dominant region. When (NH 4 ) 2 CO 3 was used as the carbon source, the Ca 2+ ions carbonation rate was hardly affected by pH, while NH 4 HCO 3 was the opposite. When the pH of the leachate decreased from 8.67 to 6.20, the carbonation rate of (NH 4 ) 2 CO 3 decreased from 99.32% to 98.42%, while the carbonation rate of NH 4 HCO 3 decreased from 96.28% to 37.71%. Meanwhile, this research also probed the influence of the nucleating agent on the carbonation rate and carbonation products. The addition of nucleating agent can increase the carbonation rate. For a CH 3 COOH concentration of 0.6 M for mixed leaching, the carbonation rate was increased by 26.81% with the addition of nucleating agent. Meanwhile, the nucleating agent can also induce the growth of CaCO 3 toward the crystal form of the nucleating agent itself. When (NH 4 ) 2 CO 3 and NH 4 HCO 3 were used as the carbon sources, CaCO 3 mainly exists in the crystal form of vaterite, and after adding the nucleating agent, the crystal form changes to calcite.
研究领域:
环境科学
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化学工程
·
材料科学
·
地球化学
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产品关联
DOI
高影响因子
Nature Chemical Biology
·
2024
·
IF 12.9
Niu Hongyan,Li Meng-Yin,Gao Yan,Li Jun-Ge,Jiang Jie,Ying Yi-Lun,Long Yi-Tao
Sulfation is considered the most prevalent post-translational modification (PTM) on tyrosine; however, its importance is frequently undervalued due to difficulties in direct and unambiguous determination from phosphorylation. Here we present a sequence-independent strategy to directly map and quantify the tyrosine sulfation states in universal native peptides using an engineered protein nanopore. Molecular dynamics simulations and nanopore mutations reveal specific interactions between tyrosine sulfation and the engineered nanopore, dominating identification across diverse peptide sequences. We show a nanopore framework to discover tyrosine sulfation in unknown peptide fragments digested from a native protein and determine the sequence of the sulfated fragment based on current blockade enhancement induced by sulfation. Moreover, our method allows direct observation of peptide sulfation in ultra-low abundance, down to 1%, and distinguishes it from isobaric phosphorylation. This sequence-independent strategy suggests the potential of nanopore to explore specific PTMs in real-life samples and at the omics level.
研究领域:
生物化学
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分子生物学
·
蛋白质组学
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产品关联
DOI
PubMed
高影响因子
Chemistry Central Journal
·
2015
·Vol. 9
·期 1
·1-10
·
IF 2.187
Chen Feng,Tan Yin-Feng,Li Hai-Long,Qin Zhen-Miao,Cai Hong-Die,Lai Wei-Yong,Zhang Xiao-Po,Li Yong-Hui,Guan Wei-Wei,Li You-Bin,Zhang Jun-Qing
Background Galangin (3,5,7-trihydroxyflavone) is present in high concentrations in herbal medicine such as Alpinia officinarum Hance. Galangin shows multifaceted in vitro and in vivo biological activities. The number and position of hydroxyl groups in this molecule play an important role in these biological activities. However, these hydroxyl groups undergo glucuronidation and sulfation in in vitro assay system. However, the systemic exposure to galangin after dosing in animals and/or humans remains largely unknown. Thus it is not clear whether the galangin exists in the body at concentrations high enough for the biological effects. Furthermore, the metabolite identification and the corresponding plasma pharmacokinetics need to be characterized.Results Two LC-MS/MS methods were developed and validated and successfully applied to analyze the parent drug molecules and aglycones liberated from plasma samples via β-glucuronidase hydrolysis. Our major findings were as follows: (1) The routes of administration showed significant influences on the systemic exposure of galangin and its metabolites. (2) Galangin was preferentially glucuronidated after p.o. dosing but sulfated after i.v. medication. (3) Kaempferol conjugates were detected demonstrating that oxidation reaction occurred; however, both glucuronidation and sulfation were more efficient. (4) Oral bioavailability of free parent galangin was very low.Conclusion sSystemic exposure to galangin and its metabolites was different in rat plasma between oral and intravenous administration. Further research is needed to characterize the structures of galangin conjugates and to evaluate the biological activities of these metabolites.
Galangin was preferentially glucuronidated after p.o. dosing but sulfated after i.v. medication.
研究领域:
药理学
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药物代谢动力学
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DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2025
·
IF 12.5
Xingping Zhou,Silin Wu,Peng Liu,Liming Wang,Fengwei Xie
Starch-based gels represent promising bioinks for 3D-printed cell scaffolds due to their biosafety, biocompatibility, and biodegradability. However, their widespread adoption has been hindered by inadequate formability and poor self-supporting properties. Here, we introduce an innovative starch-dominated hydrogel system achieved through dual methacrylation of normal corn starch and chitosan, enabling the fabrication of biodegradable cell scaffolds. While methacrylated starch alone (substitution degree: 0.013) exhibited insufficient printing accuracy even with UV assistance, the optimized 10:1 (starch/chitosan, w /w) blend of methacrylated chitosan (substitution degree: 0.27) demonstrated dramatically enhanced 3D printing formability and precision when combined with UV crosslinking. Rheological analysis demonstrated that blending methacrylated starch with methacrylated chitosan reduced flow stress ( τ f ), improving printability while retaining shear-thinning behavior. Incorporation of 10 % glycerol enhanced biomacromolecular compatibility, as evidenced by rheological results and homogenous microstructures in SEM, enabling high-fidelity printing of intricate architectures. UV-cured scaffolds exhibited tunable compressive strength (150–200 kPa) and deformation rate (50–60 %), balancing mechanical compliance with tissue safety. The material's hydrophilic surface (contact angle: 30–60°) supported robust cell adhesion, while in vitro assays confirmed exceptional biocompatibility (96 % cell viability) and controlled biodegradation in α-amylase/lysozyme solutions. This work establishes starch as a primary matrix for bioinks, advancing sustainable, high-precision 3D printing in biomedicine.
研究领域:
生物材料
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组织工程
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生物医学
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高分子化学
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产品关联
DOI
PubMed
高影响因子
EXPERIMENTAL BIOLOGY AND MEDICINE
·
2016
·
IF 2.542
Yixuan Wang,Yun Chen,Hongxu Du,Jingjing Yang,Ke Ming,Meiyun Song,Jiaguo Liu
Duck hepatitis A virus (DHAV) (Picornaviridae) causes an infectious disease in ducks which results in severe losses in duck industry. However, the proper antiviral supportive drugs for this disease have not been discovered. Polysaccharide is the main ingredient of Astragalus that has been demonstrated to directly and indirectly inhibit RNA of viruses replication. In this study, the antiviral activities of Astragalus polysaccharide (APS) and its derivatives against DHAV were evaluated and compared. APS was modified via the sodium trimetaphosphate and sodium tripolyphosphate (STMP-STPP) method and chlorosulfonic acid-pyridine method to obtain its phosphate (pAPS) and sulfate (sAPS), respectively. The infrared structures of APS, pAPS, and sAPS were analyzed with the potassium bromide disc method. Additionally, the antiviral activities were evaluated with the MTT ((4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide) method in vitro and the artificial inoculation method in vivo. The clinical therapy effects were evaluated by mortality rate, liver function-related biochemical indicators, and visual changes in pathological anatomy. The anti-DHAV proliferation effects of APS, pAPS, and sAPS on the viral multiplication process in cell and blood were observed with the reverse transcription-polymerase chain reaction method. The results revealed that pAPS inhibited DHAV proliferation more efficiently in the entire process of viral multiplication than APS and sAPS. Moreover, only pAPS significantly improved the survival rate to 33.5% and reduced the DHAV particle titer in the blood as well as liver lesions in clinical trials. The results indicated that pAPS exhibited greater anti-DHAV activity than APS and sAPS both in vitro and in vivo.
研究领域:
病毒学
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药理学
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分子生物学
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DOI
PubMed
高影响因子
GREEN CHEMISTRY
·
2023
·Vol. 25
·期 13
·5041-5050
·
IF 9.8
Xue Gao,Lei Zhang,Mei Cui,Renliang Huang,Wei Qi,Rongxin Su
Phosphorylated cellulose nanocrystals (P-CNCs) are important derivatives of cellulose nanocrystals (CNCs), which have attracted much attention in food, cosmetics and biomedicines. However, the lack of suitable industrial manufacturing technology impedes the commercial application of P-CNCs. Here, we report a facile and green process combining pre-phosphorylation with mechanical fibrillation for P-CNC production. The pre-phosphorylation process was optimised to reduce raw material and energy consumption and improve the quality of P-CNCs, and the corresponding environmental performances were further evaluated by life cycle assessment (LCA). P-CNCs with high charge content (2.33 mmol g−1) and high crystallinity (87.3%) were obtained efficiently under an optimal molar ratio (cellulose biomass : NH4H2PO4 : urea) of 1 : 0.3 : 1.2 by curing at 150 °C for 30 min and showed superior flame retardant performance. Furthermore, compared with the present production processes based on in situ phosphorylation and post-phosphorylation, this facile process exhibited not only better environmental performance but also superior economic performance, as the LCA and economic evaluation results revealed. Therefore, this eco-efficient process exhibits great potential in the industrial production of P-CNCs.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ORGANIC & BIOMOLECULAR CHEMISTRY
·
2020
·Vol. 18
·期 42
·8709-8715
·
IF 3.412
Ling Xu,Yan Zhang,Yi-Ming Li,Xian-Fu Lu
As an autophagic adaptor, p62 specifically targets ubiquitinated proteins to an autophagosome for lysosomal degradation through a critical ubiquitin-associated (UBA) domain. Recent research studies reported that the Ser403 and Ser407 sites on the UBA domain were modified by phosphorylation, increasing the binding affinity between p62 and ubiquitin (Ub). However, the exact role of each phosphorylation site in the regulation of the UBA domain and Ub binding remains unclear. In this text, we applied total chemical synthesis to prepare four types of phosphorylated UBAs, among which the bisphosphorylated UBA was successfully synthesized via the pseudo-dipeptide unit and auxiliary-mediated hydrazide-based native chemical ligation (NCL). Isothermal titration calorimetry (ITC) assays showed that the phosphorylation at S407 enhanced the binding affinity between UBA and Ub, while that at S403 did not. It was suggested that phosphorylation at S407 might be important for promoting the interplay between the UBA domain and Ub, whereas phosphorylation at S403 was not directly involved in this interaction.
研究领域:
生物化学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Frontiers in Pharmacology
·
2021
·
IF 5.811
Yang Siwen,Qu Yunhe,Chen Jiyu,Chen Si,Sun Lin,Zhou Yifa,Fan Yuying
Insufficient pancreatic β-cell or insulin-producing β-cell are implicated in all types of diabetes mellitus. Our previous studies showed bee pollen polysaccharide RBPP-P improves insulin resistance in type 2 diabetic mice by inhibiting liver fat deposition. However, its potential of regulating β-cell function and integrity is not fully known. Herein, we observed that β-cell proliferation (n = 10), insulin synthesis (n = 5, p = 0.01684) and insulin incretion (n = 5, p = 0.02115) were intensely activated in MIN6 cells when treatment with RBPP-P. In alloxan-induced diabetic mice, oral administration of RBPP-P (n = 10) effectively decreased the blood glucose (p = 0.0326), drink intake (p < 0.001) and urine (p < 0.001). It directly stimulated phosphorylation of p38 (p = 0.00439), ERK (p = 0.02951) and AKT (p = 0.0072) to maintain the islet function and mass. Thus, our data suggest that RBPP-P is a natural compound to regulate β-cell proliferation and function, indicating it might have therapeutic potential against type 1 diabetes.
研究领域:
药理学
·
内分泌学
·
糖尿病研究
✓ 已验证
DOI
PubMed
高影响因子
Food Chemistry-X
·
2024
·
IF 6.5
Xiu-Xiu Zhang,Wang-Wei Zhang,Zhi-Jing Ni,Kiran Thakur,Jian-Guo Zhang,Mohammad Rizwan Khan,Wen-Di Xu,Zhao-Jun Wei
Recent studies have witnessed that chemical modification can improve the physicochemical and functional properties of plants' polysaccharides. Herein, we modified the natural Lycium barbarum seed dreg polysaccharides (LBSDPs) by sulfation (S-LBSDPs), phosphorylation (P-LBSDPs), and carboxymethylation (C-LBSDPs), and evaluated the chemical composition and antioxidant activity of their derivatives. Natural polysaccharides and their derivatives exhibited typical polysaccharide absorption peaks and characteristic group absorption peaks in FT-IR spectra along with maximum UV absorption. After modification, the total sugar and protein contents of the derivatives were decreased, whereas the uronic acid content was increased. Among the three derivatives, sulfated polysaccharides displayed excellent thermal stability. S-LBSDP and P-LBSDP showed the highest ABTS radical scavenging and reducing power while S-LBSDPs and C-LBSDPs showed better DPPH radical scavenging effect, and P-LBSDPs showed considerable Fe 2+ chelating ability. Our data indicate that chemical modifications can impart a positive effect on the antioxidant potential of plant-derived polysaccharides.
研究领域:
食品科学
·
药剂化学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）