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Achyranthes bidentata polypeptides prevent apoptosis by inhibiting the glutamate current in cultured hippocampal neurons 被引量:9
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作者 Rong-Lu Pan Wen-Qing Hu +3 位作者 Jie Pan Li Huang Cheng-Cheng Luan Hong-Mei Shen 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第6期1086-1093,共8页
Glutamate-induced excitotoxicity plays a critical role in the neurological impairment caused by middle cerebral artery occlusion.Achyranthes bidentata polypeptides have been shown to protect against neurological funct... Glutamate-induced excitotoxicity plays a critical role in the neurological impairment caused by middle cerebral artery occlusion.Achyranthes bidentata polypeptides have been shown to protect against neurological functional damage caused by middle cerebral artery occlusion,but the underlying neuroprotective mechanisms and the relationship to glutamate-induced excitotoxicity remain unclear.Therefore,in the current study,we investigated the protective effects of Achyranthes bidentata polypeptides against glutamate-induced excitotoxicity in cultured hippocampal neurons.Hippocampal neurons were treated with Mg^2+-free extracellular solution containing glutamate(300μM)for 3 hours as a model of glutamate-mediated excitotoxicity(glutamate group).In the normal group,hippocampal neurons were incubated in Mg^2+-free extracellular solution.In the Achyranthes bidentata polypeptide group,hippocampal neurons were incubated in Mg^2+-free extracellular solution containing glutamate(300μM)and Achyranthes bidentata polypeptide at different concentrations.At 24 hours after exposure to the agents,3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and Hoechst 33258 staining were used to assess neuronal viability and nuclear m'orphology,respectively.Caspase-3 expression and activity were evaluated using western blot assay and colorimetric enzymatic assay,respectively.At various time points after glutamate treatment,reactive oxygen species in cells were detected by H2 DCF-DA,and mitochondrial membrane potential was detected by rhodamine 123 staining.To examine the effect of Achyranthes bidentata polypeptides on glutamate receptors,electrophysiological recording was used to measure the glutamate-induced inward current in cultured hippocampal neurons.Achyranthes bidentata polypeptide decreased the percentage of apoptotic cells and reduced the changes in caspase-3 expression and activity induced by glutamate.In addition,Achyranthes bidentata polypeptide attenuated the amplitude of the glutamate-induced current.Furthermore,the glutamate-induced increase in intracellular reactive oxygen species and reduction in mitochondrial membrane potential were attenuated by Achyranthes bidentata polypeptide treatment.These findings collectively suggest that Achyranthes bidentata polypeptides exert a neuroprotective effect in cultured hippocampal neurons by suppressing the overactivation of glutamate receptors and inhibiting the caspase-3-dependent mitochondrial apoptotic pathway.All animal studies were approved by the Animal Care and Use Committee,Nantong University,China(approval No.20120216-001)on February 16,2012. 展开更多
关键词 Achyranthes bidentata polypeptides APOPTOSIS caspase-3 EXCITOTOXICITY GLUTAMATE receptors MITOCHONDRIAL dysfunction MITOCHONDRIAL membrane potential neuroprotection reactive oxygen species STAUROSPORINE
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Facile Preparation of Polypeptides:Moisture Insensitive and Superfast Ring Opening Polymerization of N-Carboxyanhydrides 被引量:3
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作者 栾世方 《材料导报》 EI CAS CSCD 北大核心 2019年第1期1-2,共2页
(a)NCA polymerization initiated by LiHMDS or other initiators in THF,initiator i)n-hexylamine,ii)HMDS,iii)bipyNi(COD);(b)LiHMDS-initiated open vessel polymerization of BLGNCA at 26 mg and 2 g scale;(c)GPC traces of po... (a)NCA polymerization initiated by LiHMDS or other initiators in THF,initiator i)n-hexylamine,ii)HMDS,iii)bipyNi(COD);(b)LiHMDS-initiated open vessel polymerization of BLGNCA at 26 mg and 2 g scale;(c)GPC traces of poly-BLG at variable DP;(d)Reaction rates of LiHMDS and hexylamine initiated BLGNCA polymerization in THF with NCA:initiator ratio of 100∶1 and initial NCA concentration at 0.2 mol/L;(e)CD spectra of poly-BLG at variable DP prepared from LiHMDS-initiated NCA polymerization. 展开更多
关键词 FACILE PREPARATION polypeptides:moisture insensitive
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Synthesis,Characterization and Phase Behaviors of Polypeptides Bearing Biphenyl Mesogens and Oligo-Ethylene-Glycol Tails 被引量:2
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作者 Qiu-lin Yuan Wen-jun Liu +2 位作者 Yong Deng Ying Ling 唐浩宇 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2015年第8期1150-1161,共12页
A series ofpolypeptides bearing biphenyl mesogenic side-chains and oligo-ethylene-glycol (OEG) tails (PPLGn-g- BPOEGm, n = 26 and 63, m = 2, 3, and 7) has been synthesized via a 1,3-dipolar cycloaddition with quan... A series ofpolypeptides bearing biphenyl mesogenic side-chains and oligo-ethylene-glycol (OEG) tails (PPLGn-g- BPOEGm, n = 26 and 63, m = 2, 3, and 7) has been synthesized via a 1,3-dipolar cycloaddition with quantitative grafting density. FTIR results revealed that the polypeptides adopted highly stable a-helix in the temperature range of 25-200 ℃. DSC, POM and WAXS analysis revealed that PPLGn-g-BPOEGm (m ≤ 3) samples with short OEG tail length showed two main phase transitions including crystal to liquid crystalline (smectie C, SmC) phase transition and the melting transition of crystalline E-phase, while PPLG,-g-BPOEG7 with longer OEG tail length (m = 7) exhibited the melting transitions without the formation of liquid crystalline phase. 展开更多
关键词 Liquid-crystalline polymers polypeptides Click chemistry Smectic phases.
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DEFENSE MECHANISMS OF URINARY BLADDER:STUDIES ON ANTIMICROBIAL POLYPEPTIDES FROM BLADDER MUCOSA 被引量:1
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作者 吴琦 王伯瑶 《Chinese Medical Sciences Journal》 CAS CSCD 1999年第1期17-22,共6页
The acid soluble extract of the bladder mucosal surface was obtained by washing out the bladder with dilute acetic acid in the presence of protease inhibitors. The wash out materials from... The acid soluble extract of the bladder mucosal surface was obtained by washing out the bladder with dilute acetic acid in the presence of protease inhibitors. The wash out materials from rats, rabbits, pigs, and humans manifested strong bactericidal activity against E.coli in vitro. The ultrafiltrate of the human material, which contained two major peptides with apparent molecular masses of 6 7 kD and 8 5 kD, respectively, showed potent bactericidal activity against E. coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Streptococcus sanguis.Three antibacterial polypeptides (PiBPs) were purified from the porcine material. The molecular masses of PiBP 5, PiBP 11 and PiBP 25 were 5773.3 Da, 11127.8 Da and 25073 Da, respectively. PiBP 5 was unusually rich in glycine, serine and threonine residues(20 0, 16 3 and 10 4 mo1%, respectively), and N terminal amino acid sequencing revealed that PiBP 5 was homologous (83 3% identity in an 18 residue overlay) to the “tail” of human cytokeratin 7. Although the amino acid compositions of PiBP 11 and PiBP 25 were established, both had blocked N termini and primary sequence data were not obtained. These results provided evidence indicating that the presence of peptides in the bladder mucosa could enable it to kill adherent bacteria. 展开更多
关键词 urinary bladder defense mechanisms antimicrobial polypeptides
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Force-Regulated Adhesion and Activation Study of Integrin Targeting Polypeptides
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作者 Ke Ding Zhengjiao Cao +2 位作者 Quan Long Ting Xiong Botao Xiao 《医用生物力学》 EI CAS CSCD 北大核心 2019年第A01期155-155,共1页
Integrins are heterodimeric cell surface receptors that bind to ligands on another cell,e.g.intercellular adhesion molecule 1(ICAM-1),or the extracellular matrix.Integrins play an important role in immune system,and t... Integrins are heterodimeric cell surface receptors that bind to ligands on another cell,e.g.intercellular adhesion molecule 1(ICAM-1),or the extracellular matrix.Integrins play an important role in immune system,and they participate in inflammation,thrombosis,and proliferation,migration and apoptosis of tumor cells.They mediate adhesion and transduce signals across the membrane usually under the influence of forces.A recent study has shown that integrins bind and activate transforming growth factorβisoform(TGF-β)which is involved in tumor suppression and growth,and blocking the binding of TGF-βto integrin can inhibit tumor growth.RGD(arginine-glycine-aspartate)small peptide,which competitively inhibits ligand binding to integrins,has been approved as an injectable drug.However,when the RGD is used to block cancer-related extracellular signaling pathways,it will also cause activation of integrins for a period,and stimulate the transduction of intracellular signals constantly.Therefore,it is necessary to explore for new drugs that can selectively control conformational state of integrins without activating or blocking all of them.In this study,we selected two small peptides,KQAGDV and RTDLDSLRT,that combined with integrins and do not contain an RGD sequence.The non-RGD polypeptide RTDLDSLRT has been reported to have a binding site with integrins and the binding affinity is on nanomolar scale.For the motif of the fibrinogen y chain C-terminal KQAGDV,it can adhere to the head of the integrins.The micropipette aspiration technique and electron microscopy techniques were used to study the adhesion and activation of integrins by peptides,respectively.Micropipette aspiration technique was used to investigate the adhesion frequency of peptide and integrin on Jurkat cell.The pressure system was used to supply a controllable negative pression to the microtube,and two micropipettes were used to absorb red blood cells and Jurkat cells,respectively.The red blood cells were coated with small peptides and can serve as a force sensor after being sucked when two cells were connected.The binding kinetics of integrin and peptides interactions was determined by fitting the curves constructed using adhesion probability between two cells as a function of time.The curves were fitted using a small system probabilistic kinetic model to estimate a pair of kinetic parameters,including the zero force reverse rate kr0,and the cellular binding affinity Acmrm1Ka0.The adhesion frequency yielded P(t)=75%and 57%for RGD and KQAG DV peptides,respectively.We obtained Acmrm1Ka0=1.40 and kr0=0.32 s-1,for RGD,and Acmrm1Ka0=0.85 and kr0=0.54 s-1 for KQAGDV.The RGD peptide has a higher adhesion frequency and lower dissociation rate than the KQAGDV peptide.Electron microscopy techniques was used to observe the activation of integrins by peptides.Jurkat cell expressing integrins was bound to a magnetic bead and bottom plate which were coated with different integrin-binding peptides.Then,we manipulated the beads in a controlled direction by changing the magnetic field nearby,and the forces were applied to the cell.The target cells were fixed and then observed by scanning electron microscope or transmission electron microscope.Jurkat cells contain abundant flexible microvilli of which there are many parallel bundles of actin filaments inside.By electron microscopy analysis,the cell connected with magnetic bead coated with RGD were found to be protruded and the size of microvilli increased up to#-fold of the length of the KQAGDV sample.The microvilli exhibited a curved agglomerate structure under a force-free condition.Moreover,a higher proportion of cells were activated in the presence of RGD than KQAGDV.In conclusion,the binding affinity of KQAGDV to integrin is weaker than RGD,and KQAGDV can bind with integrins effectively with a lower activated proportion.Our results indicate the peptides may selectively bind to integrins without activating them. 展开更多
关键词 Force-Regulated ADHESION ACTIVATION Study INTEGRIN TARGETING polypeptides
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Protective effects of Achyranthes bidentata polypeptides on retinal ganglion cells post-optic nerve crush in rats
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作者 Nan Hu Qi Zhao +2 位作者 Fangling Zhang Junfang Zhang Xiaosong Gu 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第15期1164-1168,共5页
Achyranthes bidentata polypeptides(ABPP) have been reported to inhibit apoptosis of retinal ganglion cells(RGCs).The present study investigated the protective effects of ABPP on RGCs in a rat model of optic nerve ... Achyranthes bidentata polypeptides(ABPP) have been reported to inhibit apoptosis of retinal ganglion cells(RGCs).The present study investigated the protective effects of ABPP on RGCs in a rat model of optic nerve injury.With prolonged injury time,RGC densities were gradually decreased.ABPP(5 μg) significantly increased RGC densities and upregulated growth associated protein 43 expression in rats with optic nerve injury.Results demonstrate that ABPP can protect RGCs and promote axonal growth after optic nerve crush. 展开更多
关键词 Achyranthes bidentata polypeptides optic nerve crush retinal ganglion cells growth associated protein 43 neural regeneration
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Determined of antioxidant activity and preventing DNA damage effect of peanut polypeptides by chemiluminescence method
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作者 LIU Li-na LU Jing +1 位作者 HE Dong-ping ZHANG Sheng-hua 《Journal of Life Sciences》 2009年第9期43-48,共6页
To estimate the antioxidant activities of Peanut polypeptides (PPs) by using a chemiluminescence (CL) method in vitro. The scavenging ability of PPs on superoxide anion, hydroxide radical, and hydrogen peroxide wa... To estimate the antioxidant activities of Peanut polypeptides (PPs) by using a chemiluminescence (CL) method in vitro. The scavenging ability of PPs on superoxide anion, hydroxide radical, and hydrogen peroxide was determined by the Pyrogallol-Luminol system, the CuSO4-Phen-Vc-H2O2 system, and the luminol-H2O2 system, respectively. DNA damage preventing the effect of PPs was determined by the CuSO4-Phen-Vc-H2O2-DNA CL system. The results shows that PPs had good effect on the scavenging ability of superoxide anion (IC50=9.68±0.12 mg/ml). PPs could scavenge hydroxide radical effectively (the IC50 value was 46.06±0.08 μg/ml). PPs had a good scavenging ability on hydrogen peroxide, which had a relatively low IC50 value (0.17±0.07 mg/ml). PPs (the IC50 value was0.72±0.11 mg/ml) were powerful on the DNA damage preventing effect. PPs possesses a good scavenging potency on ROS in different systems, but different results exist in different systems. 展开更多
关键词 peanut polypeptides CHEMILUMINESCENCE antioxidant activity in vitro DNA damage
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Cationic polypeptides in a concept of oppositely charged polypeptides as prevention of postsurgical intraabdominal adhesions
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作者 Karolin Isaksson Daniel Akerberg +1 位作者 Katarzyna Said Bobby Tingstedt 《Journal of Biomedical Science and Engineering》 2011年第3期200-206,共7页
Background: Two differently charged polypeptides, α-poly-L-lysine and poly-L-glutamate, have previously been shown to effectively reduce postoperative intraabdominal adhesions. Though α-poly-L-lysine showed toxicity... Background: Two differently charged polypeptides, α-poly-L-lysine and poly-L-glutamate, have previously been shown to effectively reduce postoperative intraabdominal adhesions. Though α-poly-L-lysine showed toxicity in doses too close to the lowest therapeutic dose, the aim in the present study was to investigate the possible antiadhesive effect of another four cationic polypeptides. Materials/Methods: 125 mice were studied with a standardized and reproducible adhesion model and given epsilon poly-L-lysine, lactoferrin, lysozyme and polyarginine respectively in a combination with poly-L-glutamate. Epsilon poly-L-lysine was also tested in different concentrations and as single treatment. Results: All four cationic polypeptides above showed a significantly better anti-adhesive effect than the controls receiving saline (p<0.05). Epsilon poly-L-lysine had the best antiadhesive effect of the new substances tested in the experiment. Single treatment with the epsilon poly-L-lysine showed toxic side effects. Discussion: We have shown that epsilon poly-L-lysine, polyarginine, lysozyme and lactoferrin, in descending order, all can reduce postoperative intraabdominal adhesions in mice when combined with poly-L-glutamate. There were side effects of epsilon poly-L-lysine resembling those of α-poly-L-lysine, although less toxic. The antiadhesive effect of epsilon poly-L-lysine did not reach the level of α-poly-L-lysine. Further studies will concentrate on additional investigation, trying to modify the α-poly-L-lysine to lower its toxicity. The less toxic epsilon poly-L-lysine also needs further attention in our research of antiadhesive bioactive polypeptides. 展开更多
关键词 Postoperative Adhesions Bioactive polypeptides Molecular Structure
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Efficacy and safety evaluation of intravenous infusion of cervus and cucumis polypeptides for treatment of avascular necrosis of the femoral head: a randomized clinical trial 被引量:17
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作者 Wei Liyou Zhang Hongwei +5 位作者 Li Xinmin Yang Chunyan Wang Guoqiang Zhang Lifeng Cui Mingwu Han Lijun 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2016年第1期39-44,共6页
OBJECTIVE: To investigate the efficacy and safety of intravenous cervus and cucumis polypeptides for treating avascular necrosis of the femoral head(ANFH) in regard to pain and hip function in a randomized clinical tr... OBJECTIVE: To investigate the efficacy and safety of intravenous cervus and cucumis polypeptides for treating avascular necrosis of the femoral head(ANFH) in regard to pain and hip function in a randomized clinical trial.METHODS: A total of 96 subjects with ANFH who were recruited at the Orthopaedic Hospital Affiliated with Hebei United University and Qian Hai Femoral Head Hospital of Beijing were assigned by lottery to an intervention group(n = 48) or a control group(n = 48). All subjects underwent physical therapy and rehabilitation exercises. In addition,subjects in the intervention group were given intravenous infusions of cervus and cucumis polypeptides. Visual analogue scale(VAS), Harris hip score,and radiography or magnetic resonance imaging were applied to assess all subjects at the beginning of treatment and 3, 6, and 9 months afterward. All the subjects were followed up for 2 years.RESULTS: At the beginning of treatment, there were no statistically significant differences between the two groups in terms of the general condition of patients or the VAS and Harris hip scores(all P > 0.05). At 3, 6, and 9 months after treatment,however, the VAS score decreased and the Harris hip score increased in all patients, with the improvement of intervention group significantly greater than that of the control group(P < 0.05).The total effectiveness rates for the intervention and control groups were 89.58% and 70.83%, respectively, with the difference being statistically significant(P < 0.05). There was no statistically significant difference between the two groups in terms of the safety of the injections(P > 0.05).CONCLUSION: Intravenous infusion of cervus and cucumis polypeptides relieved pain and improved hip function of subjects with ANFH.Thus, the intravenous infusion of cervus and cucumis polypeptides was a safe, effective treatment for ANFH. 展开更多
关键词 Femur head necrosis Pain measurement Cervus and cucumis polypeptide injection Randomized clinical trial
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Controlled synthesis of polypeptides 被引量:5
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作者 Yang Liu Di Li +1 位作者 Jianxun Ding Xuesi Chen 《Chinese Chemical Letters》 SCIE CAS CSCD 2020年第12期3001-3014,共14页
Polypeptides are one kind of promising biodegradable and biocompatible biomedical polymers with the structural units of various a-amino acids.Polypeptides were first polymerized by the ring-opening polymerization(ROP)... Polypeptides are one kind of promising biodegradable and biocompatible biomedical polymers with the structural units of various a-amino acids.Polypeptides were first polymerized by the ring-opening polymerization(ROP)of α-amino acid N-carboxyanhydrides(NCAs)by Leuchs and Hermann in 1906.In the past decades,several effective strategies,including the selection of initiators,the adjustment of reaction conditions,and the introduction of catalysts,have been reported to improve the controllability of the ROP of various a-amino acid NCAs to synthesize different polypeptides with precise chemical structures and low polydispersity indexes.In this Review,the strategies,mechanisms,challenges,and opportunities for controlled synthesis of polypeptides by the ROP of differentα-amino acid NCAs have been declared. 展开更多
关键词 α-Amino acid N-carboxyanhydride Ring-opening polymerization Controlled synthesis POLYPEPTIDE Biomedical application
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Facile Synthesis of High Molecular Weight Polypeptides via Fast and Moisture Insensitive Polymerization of a-Amino Acid N-Carboxyanhydrides 被引量:5
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作者 Yue Ming Wu Wei-Wei Zhang +6 位作者 Rui-Yi Zhou Qi Chen Chen-Yu Xie Heng-Xue Xiang Bin Sun Mei-Fang Zhu Run-Hui Liu 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2020年第10期1131-1140,I0007,共11页
Polypeptides have been widely utilized in the fields of biomaterials and biomedicine.Ever since N-carboxyanhydride(NCA)was reported by Hermann Leuchs in 1906,ring-opening polymerization of NCAS has been extensively us... Polypeptides have been widely utilized in the fields of biomaterials and biomedicine.Ever since N-carboxyanhydride(NCA)was reported by Hermann Leuchs in 1906,ring-opening polymerization of NCAS has been extensively used to prepare polypeptides.Despite continuous innovations,it is still challenging to synthesize polypeptides in high molecular weight fficiently.To address this challenge,we developed KHMDS/NaHMDS initiated fast NCA polymerization that is also moisture tolerant,open-flask amenable and terminal tunable.This NCA polymerization was able to proceed in most common solvents and meet the solubility requirement of variable NCA monomers and corresponding polypeptides.KHMDS can initiate r benzy-L glutamate-N carboxyanhydride(BLG NCA)polymerization in a reaction rate 92 times faster than does hexylamine and 80 times faster than does triethylamine.This NCA polymerization also demonstrated easy and fast synthesis of gram-scale long chain polypeptides in an open flask. 展开更多
关键词 NCA polymerization POLYPEPTIDE Open vessel Fast polymerization High Mw
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SURFACE MODIFICATION OF POLYPROPYLENE MICROPOROUS MEMBRANE BY TETHERING POLYPEPTIDES 被引量:3
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作者 徐志康 Mathias Ulbricht 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2006年第5期529-538,共10页
Two kinds of polypeptides were tethered onto the surface of polypropylene microporous membrane (PPMM) through a ring opening polymerization of L-glutamate N-carboxyanhydride initiated by amino groups which were intr... Two kinds of polypeptides were tethered onto the surface of polypropylene microporous membrane (PPMM) through a ring opening polymerization of L-glutamate N-carboxyanhydride initiated by amino groups which were introduced by ammonia plasma and y-aminopropyl triethanoxysilane treatments. X-ray photoelectron spectroscopy (XPS), attenuated total reflectance Fourier transform infrared spectroscopy (FT-IR/ATR), scanning electron microscopy (SEM), together with water contact angle measurements were used to characterize the modified membranes. XPS analyses and FT-IR/ATR spectra demonstrated that polypeptides are actually grafted onto the membrane surface. The wettability of the membrane surface increases at first and then decreases with the increase in grafting degrees of polypeptide. Platelet adhesion and murine macrophage attachment experiments reveal an enhanced hemocompatibility for the polypeptide modified PPMMs. All these results give evidence that polypeptide grafting can simultaneously improve the hemocompatibility as well as reserve the hydrophobicity for the membrane, which will provide a potential approach to improve the performance of polypropylene hollow fiber microporous membrane used in artificial oxygenator. 展开更多
关键词 Polypropylene microporous membrane Graft polymerization POLYPEPTIDE Surface modification Biocompatibility.
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Helical Nonfouling Polypeptides for Biomedical Applications 被引量:2
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作者 Chong Zhang Hua Lu 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2022年第5期433-446,共14页
Synthetic polypeptides,also known as poly(α-amino acid)s(PαAAs),are biomimetic and biodegradable polymers holding great potential for a variety of biomedical applications.Possessing the same peptide bonds as natural... Synthetic polypeptides,also known as poly(α-amino acid)s(PαAAs),are biomimetic and biodegradable polymers holding great potential for a variety of biomedical applications.Possessing the same peptide bonds as natural proteins,polypeptides can also adopt typical well-defined secondary structures includingα-helix,which have been shown to significantly impact the physicochemical properties and biological outcomes of materials.In this feature article,we review the state-of-the-art progresses ofα-helical polypeptides for biomedical applications,with a special emphasis on the manipulation of helix-to-coil dynamic transition,conformation-associated anti-biofouling coatings,cellular uptake regulation,and reducing immunogenicity of polypeptide-protein conjugates.Finally,perspectives on outstanding challenges remained in this field and some important future directions are discussed. 展开更多
关键词 Poly(α-amino acid) POLYPEPTIDE HELIX Nonfouling PEPylation
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Synthesis and Cleavage Activity of Artifical Minic Polypeptides 被引量:2
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作者 Yong YE Xiao Lian HU +3 位作者 Ping LI Ming Yu NIU Li Feng CAO Yu Fen ZHAO 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第9期1197-1200,共4页
Two artificial minic polypeptides which are synthetic analogues of natural products with DNA affinity were synthesized, and theirs cleavage activity with DNA were examined. The structures of these compounds was confir... Two artificial minic polypeptides which are synthetic analogues of natural products with DNA affinity were synthesized, and theirs cleavage activity with DNA were examined. The structures of these compounds was confirmed by ^1H NMR, MS and IR. 展开更多
关键词 DNA artificial minic polypeptide cleavage agents.
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Construction of Expressing Plasmids of Recombinant FN Polypeptides with Bifunctional-domain and the Characterization of the Products Expressed in E. Coli 被引量:1
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作者 冯作化 张桂梅 +1 位作者 李东 张慧 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 1996年第2期70-74,86,共6页
Two expressing plasmids have been constructed and used to express two bifunctional-domain recombinant polypeptides of human fibronectin (FN) in E. coli. One was CH50 (Pro1239-Ser1515 of FN linked with Ala1690-Thr1960 ... Two expressing plasmids have been constructed and used to express two bifunctional-domain recombinant polypeptides of human fibronectin (FN) in E. coli. One was CH50 (Pro1239-Ser1515 of FN linked with Ala1690-Thr1960 of FN through Met) and the other was CH56 (Pro1239-Thr1960 of FN). Both of two polypeptides were capable of binding heparin and were purified by heparin-a-garose affinity chromatography. The purified products were capable of binding cells. The production of CH50 and CH56 polypeptides provided a fundamental basis for further study of the anti-metastatic function of recombinant fibronectin polypeptides. 展开更多
关键词 FIBRONECTIN recombinant polypeptide metastasis
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Structure Characterization of Silk Fibroin Crystalline Domain Polypeptides Expressed in Escherichia coli 被引量:1
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作者 王建南 闫书芹 白伦 《Journal of Donghua University(English Edition)》 EI CAS 2011年第1期1-4,共4页
The molecular conformations of four silk fibroin crystalline analogues [GAGAG-X] 16(G,Gly;A,Ala;X=Ala,Ser,Tyr or Val,designated eGA,eGS,eGY or eGV),carried out using molecular design and expressed by Escherichia coil(... The molecular conformations of four silk fibroin crystalline analogues [GAGAG-X] 16(G,Gly;A,Ala;X=Ala,Ser,Tyr or Val,designated eGA,eGS,eGY or eGV),carried out using molecular design and expressed by Escherichia coil(E.coli),were evaluated by Raman spectra analysis.The abilities of forming β-sheet structure were determined by thioflavin T(ThT) fluorescence spectra analysis.In terms of molecular conformation,except eGY that could not form significant typical molecular conformation,eGS and eGV were mainly composed of β-sheets while eGA tended to form β-turn.β-turn was also present in eGY and absent in eGS and eGV.In terms of β-sheet structure,eGS had the highest β-sheet content,followed by eGV,and eGA had the lowest content,furthermore,β-sheet structures were more stable in eGS and eGV than those in eGA and eGY. 展开更多
关键词 fibroin crystalline combination polypeptide Β-SHEET thioflavin T(ThT) Raman spectra
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Therapeutic effects of velvet antler polypeptides on hepatic fibrosis in rats
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作者 Leng-xinDUAN Cai-eWANG +2 位作者 Ji-leXIN Yi-mengDUAN Jian-gangWANG 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2015年第S1期56-57,共2页
OBJECTIVE To explore the therapeutic effects and underlying mechanisms of velvet antler polypeptides(VVAPs)in CCl4-induced experimental hepatic fibrosis in rats.METHODS Anti-hepatic fibrosis properties of VAPs were te... OBJECTIVE To explore the therapeutic effects and underlying mechanisms of velvet antler polypeptides(VVAPs)in CCl4-induced experimental hepatic fibrosis in rats.METHODS Anti-hepatic fibrosis properties of VAPs were tested by Subcutaneous injection(SC)into male Wistar rats of CCl4- induced experimental hepatic fibrosis.After SC injections for 45 consecutive days at doses of 5mg·kg-1(low dose,VAPsL),10mg·kg-1(mid-dose,VAPsM)and 20mg·kg-1(high-dose,VAPsH),the rats were sacrificed and the various indicators were evaluated and tested.Observed hepatic cells degeneration and necrosis,inflammatory infiltration and levels of serum enzymes to assess treatment of VAPs;The expression levels of superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),MDA,and hydroxyproline(HYP)in liver tissue were analyzed;RT-PCR analysis was carried out to detect the expression levels of matrix metalloproteinases2(MMP-2)and tissue inhibitor of metalloproteinases 1(TIMP-1)in liver tissue.RESULTS VAPs has obvious anti-hepatic fibrosis effects.Hepatocyte swelling,fatty degeneration was significantly reduced,reducing infiltration of inflammatory cells.Release of alanine aminotransferase(ALT)and aspartate aminotransferase(AST)decreased significantly,reduction of hyaluronic acid(HA)and laminin(LN)obviously,at the same time,the content of total protein and albumin increased significantly in serum.Activity of SOD and GSH-Px was significantly raised and the content of MDA and HYP was reduced significantly in liver tissue.Expression levels of MMP-2and TIMP-1 mRNA in liver were decreased significantly.These improvements were more significant in high-dos and mid-dose groups(P<0.05 or P<0.01 vs model group).CONCLUSION These findings suggest VAPs can significant treat the hepatic fibrosis,which may be due to protect liver cells and improve liver functions by hydroxyl radical scavenging activity and great effect of antioxidation,and decrease the gene expression of MMP-2,improving exist-environment of liver cells and decreasing the gene expression of TIMP-1,prompting degradation of extracellular matrix. 展开更多
关键词 VELVET ANTLER POLYPEPTIDE HEPATIC FIBROSIS oxidati
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Alteration of Crystallin Polypeptides in Rat Lenses during the Development of Galactose-induced Cataract
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作者 Huiren Zhao Xiaoheng Ren Department of Biochemistry,Xuzhou Medical College Xuzhou 221002,China 《眼科学报》 1993年第3期143-145,共3页
Some striking differences in relative polypeptide abundanceof crystallins were observed in normal and galactose-induced cataractouslenses of rat by means of SDS-PAGE.In the cataractous lenses aprominent band appeared ... Some striking differences in relative polypeptide abundanceof crystallins were observed in normal and galactose-induced cataractouslenses of rat by means of SDS-PAGE.In the cataractous lenses aprominent band appeared at about 25 kDa and the αA chain increasedmarkedly,whereas the relative amount of the 31 kDa band decreasedsubstantially.These alterations are similar to the changes observed duringthe incubation of young mouse lenses in glucose-free medium.Eye Science1993;9:143-145. 展开更多
关键词 rat lens galactose cataract crystallin polypeptide
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Effect of chirality on conformation and cellular uptake of poly(S-(o-nitrobenzyl)-L,D-cysteine) polypeptides
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作者 Yang Liu Chang-Ming Dong 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第4期827-831,共5页
A series of poly(S-(o-nitrobenzyl)-L,D-cysteine) polypeptides with different chirality was synthesized and their molecular structures,secondary conformations,drug release and biological properties were thoroughly ... A series of poly(S-(o-nitrobenzyl)-L,D-cysteine) polypeptides with different chirality was synthesized and their molecular structures,secondary conformations,drug release and biological properties were thoroughly investigated.The chirality of the polypeptides had effect on secondary conformations and the cellular uptake behavior of the related nanoparticles. 展开更多
关键词 Chiral polypeptide Secondary conformation Nanoparticle Drug release Cellular uptake
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Cationic Spherical Polypeptides with Immunogenic Cell Death Inducing Activity for Oncolytic Immunotherapy
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作者 Zhihui Guo Tianze Huang +7 位作者 Renyong Yin Yongchang Tian Pengqi Wan Xuan Yi Gao Li Peng Zhang Chunsheng Xiao Xuesi Chen 《CCS Chemistry》 2025年第1期180-193,共14页
Immunogenic cell death(ICD)has gained increasing attention due to its capacity to trigger anticancer immunity.Herein,we report a series of fabricated cationic spherical polypeptides(CSPs)designated CSP-0 to CSP-57,wit... Immunogenic cell death(ICD)has gained increasing attention due to its capacity to trigger anticancer immunity.Herein,we report a series of fabricated cationic spherical polypeptides(CSPs)designated CSP-0 to CSP-57,with oncolytic activity and ICDinducing ability.CSP-57 exerted the optimal broadspectrum and tumor-cell-selective cytotoxicity by disrupting cell membranes and inducing cell necrosis.Moreover,CSP-57 damaged mitochondrial membranes,thereby elevating intracellular levels of reactive oxygen species,leading to robust ICD of tumor cells featured by multiple damage-associated molecular patterns,including calreticulin,high-mobility group box 1,and adenosine triphosphate.In vivo anticancer activity determination results suggested that CSP-57 significantly delayed B16F10 tumor growth in mice by direct oncolysis and subsequent induction of ICD.The immunotherapeutic efficacy of CSP-57 was characterized by elevated ratios of cytotoxic T cells in tumors and spleens.Briefly,this work indicates that CSPs represent a promising strategy for oncolytic immunotherapy. 展开更多
关键词 cationic spherical polypeptides ONCOLYSIS mitochondrial damage immunogenic cell death IMMUNOTHERAPY
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