Flaxseed lignan macromolecules(FLM)are a class of important secondary metabolites in fl axseed,which have been widely concerned due to their biological and pharmacological properties,especially for their antioxidative...Flaxseed lignan macromolecules(FLM)are a class of important secondary metabolites in fl axseed,which have been widely concerned due to their biological and pharmacological properties,especially for their antioxidative activity.For the composition and structure of FLM,our results confirmed that ferulic acid glycoside(FerAG)was directly ester-linked with herbacetin diglucoside(HDG)or pinoresinol diglucoside(PDG),which might determine the beginning of FLM biosynthesis.Additionally,p-coumaric acid glycoside(CouAG)might determine the end of chain extension during FLM synthesis in fl axseed.FLM exhibited higher antioxidative activity in polar systems,as shown by its superior 1,1-diphenyl-2-picrylhydrazyl(DPPH)free radical scavenging capacity compared to the 2,2’-azinobis(3-ehtylbenzothiazolin-6-sulfnic acid)(ABTS)cation free radical scavenging capacity in non-polar systems.Moreover,the antioxidative activity of FLM was found to be highly dependent on its composition and structure.In particular,it was positively correlated with the number of phenolic hydroxyl groups(longer FLM chains)and inversely related to the steric hindrance at the ends(lower levels of FerAG and CouAG).These fi ndings verifi ed the potential application of FLM in nonpolar systems,particularly in functional food emulsions。展开更多
Poly(isoprene-co-glycidyl methacrylate)epoxy macromolecules were synthesized via reversible addition-fragmentation chain transfer(RAFT)polymerization to act as interfacial mediators between talcum powder(Talc)and styr...Poly(isoprene-co-glycidyl methacrylate)epoxy macromolecules were synthesized via reversible addition-fragmentation chain transfer(RAFT)polymerization to act as interfacial mediators between talcum powder(Talc)and styrene-butadiene rubber(SBR)with the aim of improving the properties of SBR/Talc composites.The epoxy macromolecules were uniformly dispersed on the surface of Talc using the spray-drying method.Subse-quently,the modified Talc was utilized in the preparation of SBR composites.During hot vulcanization,isoprene double bonds could directly graft onto the rubber skeleton.Simultaneously,the epoxy groups opened the ring and formed covalent bonds with silanol.The interfacial covalent bonds were found to significantly enhance the dispersion of Talc and the interfacial interactions between SBR and Talc,as evidenced by scanning electron microscopy,cross-linking density measurements,and rubber processing analyzer tests.Differential scanning calorimetry results indicated that the number of interfacial covalent bonds and the content of glassy layers in the composites increased with the rise in GMA content and modified Talc.At equivalent filler loadings,epoxy macromolecules with 20 wt%and 34 wt%GMA increased the tensile strength by 31%and 49%,respectively.Concerning viscoelastic properties,composites containing interfacial covalent bonds exhibited superior stress relaxation and stress softening properties.展开更多
The BL19U2 at the Shanghai Synchrotron Radiation Facility is a small-angle X-ray scattering beamline dedicated to structural studies pertaining to biological macromolecules in solution.The beamline has been officially...The BL19U2 at the Shanghai Synchrotron Radiation Facility is a small-angle X-ray scattering beamline dedicated to structural studies pertaining to biological macromolecules in solution.The beamline has been officially opened to users in March 2015,and since then,a series of technological innovations has been developed to optimize beamline performance,thereby significantly improving the data collection efficiency and broadening the application scope of biological small-angle X-ray scattering.BL19U2 is ideal for the high-throughput screening of weakly scattered proteins,protein assemblies,nucleic acids,inorganic nanomaterials,and organic drug molecules.This paper describes the design and overview of the BL19U2 beamline.Versatile sample environments at the experimental station and some recent scientific highlights are presented.展开更多
Graphene oxide(GO), which consists of two-dimensional(2 D) sp^(2) carbon hexagonal networks and oxygen-contained functional groups, has laid the foundation of mass production and applications of graphene materials. Ma...Graphene oxide(GO), which consists of two-dimensional(2 D) sp^(2) carbon hexagonal networks and oxygen-contained functional groups, has laid the foundation of mass production and applications of graphene materials. Made by chemical oxidation of graphite, GO is highly dispersible or even solubilized in water and polar organic solvents, which resolves the hard problem of graphene processing and opens a door to wet-processing of graphene. Despite its defects, GO is easy to functionalize, dope, punch holes, cut into pieces, conduct chemical reduction, form lyotropic liquid crystal, and assemble into macroscopic materials with tunable structures and properties as a living building block. GO sheet has been viewed as a single molecule, a particle, as well as a soft polymer material. An overview on GO as a 2 D macromolecule is essential for studying its intrinsic properties and guiding the development of relevant subjects. This review mainly focuses on recent advances of GO sheets, from single macromolecular behavior to macro-assembled graphene material properties. The first part of this review offers a brief introduction to the synthesis of GO molecules. Then the chemical structure and physical properties of GO are presented, as well as its polarity in solvent and rheology behavior. Several key parameters governing the ultimate stability of GO colloidal behavior, including size, p H and the presence of cation in aqueous dispersions, are highlighted. Furthermore, the discovery of GO liquid crystal and functionalization of GO molecules have built solid new foundations of preparing highly ordered, architecture-tunable, macro-assembled graphene materials, including 1 D graphene fibers, 2 D graphene films, and 3 D graphene architectures. The GO-based composites are also viewed and the interactions between these target materials and GO are carefully discussed. Finally, an outlook is provided in this field, where GO is regarded as macromolecules, pointing out the challenges and opportunities that exist in the field. We hope that this review will be beneficial to the understanding of GO in terms of chemical structure,molecular properties, macro-assembly and potential applications, and encourage further development to extend its investigations from basic research to practical applications.展开更多
In the previous research, we found that anticancer agent LS-1-2 F could cause the vacuolation of tumor cells. Herein we investigated the effect of compound LS-1-2 F on the endocytosis of macromolecules, including fluo...In the previous research, we found that anticancer agent LS-1-2 F could cause the vacuolation of tumor cells. Herein we investigated the effect of compound LS-1-2 F on the endocytosis of macromolecules, including fluorescence quantum dots, human serum albumin, single-stranded RNA, and monoclonal antibody, into tumor cells. We found that LS-1-2 F could accelerate the endocytosis of these large molecules by laser confocal microscope and flow cytometry. The effect of LS-1-2 F on the improvement of the internalization efficiency of Herceptin biosimilar was particularly significant. Promoting endocytosis will help increase the efficiency of liquid-phase drug uptake in drug-resistant cancer cells and could potentially facilitate the use of drugs in nanoparticle delivery vehicles.展开更多
In the construction of biosensors, enzymes function as mediators converting biological signals generated by specific biological processes, into electrochemical signals. The ideology of bio-sensor design is retention o...In the construction of biosensors, enzymes function as mediators converting biological signals generated by specific biological processes, into electrochemical signals. The ideology of bio-sensor design is retention of electron transfer activity of the enzyme utilizing superior interfacial architecture. In this work a Schiff-base macromolecule has been synthesized by reflux of 2, 3-diaminonaphthalene and pyrrole-2-carboxaldehyde starting materials. The Schiff-base ligand was subsequently complexed with FeCl2?4H2O under reflux, to produce the Fe-Schiff-base complex. The Schiff-base ligand and Fe-Schiff-base complex were characterized using nuclear magnetic resonance (NMR) spectroscopy, Ultra Violet/Visible (UV/Vis) spectroscopy, Fourier transfer infrared resonance (FTIR) and electron energy loss spectroscopy (EELS) to confirm the structure of the synthesis products. NMR spectroscopy confirmed the imide linkage of Schiff-base formation as two symmetrical peaks at 8.1 and 7.7 ppm respectively. Comparison of starting materials and product spectra by UV/Vis spectroscopy confirmed the disappearance of the diaminonaphthalene peak at 250 nm as evidence of complete conversion to product. FTIR spectroscopy of the Schiff-base ligand confirmed the formation of the imine bond at 1595 cm-1. EELS spectra comparing FeCl2?4H2O and the Fe-Schiff-base complex, showed good agreement in the energy loss profiles associated with changes to the electronic arrangement of Fe d-orbitals. EDS clearly identified a spectral band for Fe (7 - 8 eV) in the Fe-Schiff-base complex. Electrochemical evaluation of the Fe-Schiff-base complex was compared to the electrochemical signature of denatured cytochrome-C using cyclic voltammetry and square wave voltammetry. The Fe2+/Fe3+ quasi-reversible behavior for iron in the metallated complex was observed at -0.430 V vs. Ag/AgCl, which is consistent with reference values for iron in macromolecular structures.展开更多
An encoding method has a direct effect on the quality and the representationof the discovered knowledge in data mining systems. Biological macromolecules are encoded by stringsof characters, called primary structures....An encoding method has a direct effect on the quality and the representationof the discovered knowledge in data mining systems. Biological macromolecules are encoded by stringsof characters, called primary structures. Knowing that data mining systems usually use relationaltables to encode data, we have then to re-encode these strings and transform them into relationaltables. In this paper, we do a comparative study of the existing static encoding methods, that arebased on the Biologist know-how, and our new dynamic encoding one, that is based on the constructionof Discriminant and Minimal Substrings (DMS). Different classification methods are used to do thisstudy. The experimental results show that our dynamic encoding method is more efficient than thestatic ones, to encode biological macromolecules within a data mining perspective.展开更多
1 Results Several methods have been elaborated in this laboratory allowing preparation of macromolecules with phosphodiester bonds,and having sequence of atoms similar as in the chains of biomacromolecules - nucleic o...1 Results Several methods have been elaborated in this laboratory allowing preparation of macromolecules with phosphodiester bonds,and having sequence of atoms similar as in the chains of biomacromolecules - nucleic or teichoic acids (TA),namely:-(C)n-O-PO-,where n=2 (for teichoic acids) or 3.These methods,to be discussed in the lecture,are based on the ring-opening polymerization,transesterification,and recently elaborated direct addition of phosphoric acid to diepoxides.For the first time an attempt h...展开更多
According to literature,certain microorganism productions mediate biological effects.However,their beneficial characteristics remain unclear.Nowadays,scientists concentrate on obtaining natural materials from live cre...According to literature,certain microorganism productions mediate biological effects.However,their beneficial characteristics remain unclear.Nowadays,scientists concentrate on obtaining natural materials from live creatures as new sources to produce innovative smart biomaterials for increasing tissue reconstruction in tissue engineering and regenerative medicine.The present review aims to introduce microorganism-derived biological macromolecules,such as pullulan,alginate,dextran,curdlan,and hyaluronic acid,and their available sources for tissue engineering.Growing evidence indicates that these materials can be used as biological material in scaffolds to enhance regeneration in damaged tissues and contribute to cosmetic and dermatological applications.These natural-based materials are attractive in pharmaceutical,regenerative medicine,and biomedical applications.This study provides a detailed overview of natural-based biomaterials,their chemical and physical properties,and new directions for future research and therapeutic applications.展开更多
A model for describing the behavior of macromolecules in adsorbed layers is developed by introducing a concept of distribution density of layer thicknessU based on stochastic process and probabilistic statistics. The ...A model for describing the behavior of macromolecules in adsorbed layers is developed by introducing a concept of distribution density of layer thicknessU based on stochastic process and probabilistic statistics. The molecular behavior of layers adsorbed on clay particle surfaces is discussed; the random distribution and its statistics of the layer thickness are given by incorporating experimental results with an ionic polyelectrolyte with the molecular weight of 1.08 x 106and chain charged density of 0.254.展开更多
The Mariana Trench is the deepest location on earth and harbors unique microbial communities as evidenced by 16S rRNA gene amplicon and metagenomic sequencing.Obtaining culturable microorganisms from the Mariana Trenc...The Mariana Trench is the deepest location on earth and harbors unique microbial communities as evidenced by 16S rRNA gene amplicon and metagenomic sequencing.Obtaining culturable microorganisms from the Mariana Trench will contribute to a further understanding of hadal biogeochemical processes and act as a unique microbial reservoir with potential applications.Here,825 bacterial strains,identified by 16S rRNA gene sequencing,were isolated from 12 water depths(0-10,400 m)of the Mariana Trench with 2216E and R2A media at 4℃ or 28℃ on four cruises during 2015-2017.These bacteria belong to four phyla,nine classes,27 orders,45 families and 108 genera.Alphaproteobacteria,Gammaproteobacteria,Actinobacteria_c,Bacilli and Flavobacteriia were the most abundant classes,accounting for 37.9%,33.0%,11.8%,8.6%and 8.0%of the total bacterial isolates,respectively.2216E and R2A media were found to have a better selectivity to Bacilli and Flavobacteriia,respectively.Fifty strains were potential novel bacterial species with a 16S rRNA gene similarity<98.65%,and a higher percentage of novel strains were obtained from R2A than 2216E medium.Additionally,301(150 species)out of 354 strains(178 species)selected from each depth could degrade at least one of the ten kinds of macromolecules tested.These results indicate that there is a high diversity of culturable bacteria in the Mariana Trench and they can produce a variety of extracellular enzymes.Our study provides a valuable resource of microorganisms for investigating their biogeochemical roles in the Mariana Trench and for industrial applications.展开更多
Poly(ester amide)s(PEAs)attract much attention as a new kind of biodegradable polymers.However,the synthesis of PEAs with sequence-regulated chain structures is still complicated due to the multistep polymerization,hi...Poly(ester amide)s(PEAs)attract much attention as a new kind of biodegradable polymers.However,the synthesis of PEAs with sequence-regulated chain structures is still complicated due to the multistep polymerization,high monomer purity,as well as the usage of organic solvents,which greatly inhibits its development and applications.Herein,a one-pot strategy without solvent was developed to synthesize the alternating PEA fromα,ω-amino alcohol and dicarboxylic acid by sequential polycondensation,where water was used as the controlling agent for amidation and esterification.Specifically,the amidation and esterification were controlled to proceed in turn by adding or removing water,realizing the one-pot preparation of alternating PEAs.The resultant PEA is characterized by^1H-and^(13)C-NMR,and its chain structure is confirmed to be highly quasi-alternating similar to alternating PEAs prepared by classical methods The evaluations from DSC and DMA demonstrate that the properties of quasi-alternating PEA(T_(m)=102℃,ΔH_(m)=30J·g^(-1))are far superior to those of random PEA(T_(m)=72℃,ΔH_(m)<1 J·g^(-1)).展开更多
BACKGROUND Breast cancer brain metastasis(BCBM)is an advanced breast disease that is difficult to treat and is associated with a high risk of death.Patient prognosis is usually poor,with reduced quality of life.In thi...BACKGROUND Breast cancer brain metastasis(BCBM)is an advanced breast disease that is difficult to treat and is associated with a high risk of death.Patient prognosis is usually poor,with reduced quality of life.In this context,we report the case of a patient with HER-2-positive BCBM treated with a macromolecular mAb(ine-tetamab)combined with a small molecule tyrosine kinase inhibitor(TKI).CASE SUMMARY The patient was a 58-year-old woman with a 12-year history of type 2 diabetes.She was compliant with regular insulin treatment and had good blood glucose control.The patient was diagnosed with invasive carcinoma of the right breast(T3N1M0 stage IIIa,HER2-positive type)through aspiration biopsy of the ipsilateral breast due to the discovery of a breast tumor in February 2019.Immunohistochemistry showed ER(-),PR(-),HER-2(3+),and Ki-67(55-60%+).Preoperative neoadjuvant chemotherapy,i.e.,the AC-TH regimen(epirubicin,cyclophosphamide,docetaxel-paclitaxel,and trastuzumab),was administered for 8 cycles.She underwent modified radical mastectomy of the right breast in November 2019 and received tocilizumab targeted therapy for 1 year.Brain metastasis was found 9 mo after surgery.She underwent brain metastasectomy in August 2020.Immunohistochemistry showed ER(-)and PR.(-),HER-2(3+),and Ki-67(10-20%+).In November 2020,the patient experienced headache symptoms.After an examination,tumor recurrence in the original surgical region of the brain was observed,and the patient was treated with inetetamab,pyrotinib,and capecitabine.Whole-brain radiotherapy was recommended.The patient and her family refused radiotherapy for personal reasons.In September 2021,a routine examination revealed that the brain tumor was considerably larger.The original systemic treatment was continued and combined with intensity-modulated radiation therapy for brain metastases,followed by regular hospitalization and routine examinations.The patient’s condition is generally stable,and she has a relatively high quality of life.This case report demonstrates that in patients with BCBM and resistance to trastuzumab,inetetamab combined with pyrotinib and chemotherapy can prolong survival.CONCLUSION Inetetamab combined with small molecule TKI drugs,chemotherapy and radiation may be an effective regimen for maintaining stable disease in patients with BCBM.展开更多
This review firstly gives an overview on the importance of crystallization in natural and synthetic polymers/macromolecules.Then it introduces the typical features that have been raised by chain-like macromolecules in...This review firstly gives an overview on the importance of crystallization in natural and synthetic polymers/macromolecules.Then it introduces the typical features that have been raised by chain-like macromolecules in crystallization,including anisotropic interactions in the thermodynamic driving forces,chain folding in the crystal morphologies,chemical confinement in the copolymer crystallization,and mechanical enhancement in the stretching processes.Four features separately cover the thermodynamics and the kinetics of polymer crystallization,as well as the crystallinity and the mechanical properties of semicrystalline polymers.The review ends up with how these features enhance specific functions of crystalline polymers,which demonstrates polymer crystallization as a challenging yet promising field in the future.展开更多
Nephrolithiasis seems to be the result of crystal formation,aggregation and retention in the kidney during crystalluria.These processes have to occur within the short urinary transit time through the kidney being in t...Nephrolithiasis seems to be the result of crystal formation,aggregation and retention in the kidney during crystalluria.These processes have to occur within the short urinary transit time through the kidney being in the order of few minutes.Recently much work was done on rather qualitative aspects of nephrolithiasis like genetics,metabolism and morphology.In this review we try to provide some quantitative information on urinary supersaturation with respect to stone minerals,especially Ca oxalate(CaO x),on the formation and aggregation of Ca Ox crystals and on crystal retention in the kidney.The paper is centered on idiopathic Ca nephrolithiasis being the most frequent stone disease with only partially known pathogenesis.New aspects of the role of urinary macromolecules in stone formation and of the mechanism of crystal aggregation are provided.展开更多
The elasticity of an individual polymer nanoparticle may be greatly different from that of the bulk one. Understanding the properties of individual particles such as elasticity and deformation under external forces is...The elasticity of an individual polymer nanoparticle may be greatly different from that of the bulk one. Understanding the properties of individual particles such as elasticity and deformation under external forces is of great importance in controlling the final structures and functions of bulk materials. We study the compression properties of single polyethylenimine （PEI） particles using vibrating scanning polarization force microscopy. By controllably imaging PEI particles at different vibration amplitude set-point values, it is demonstrated that we can compress the single PEI nanoparticle with an atomic force microscopy tip in different loads. Based on the force-height and force-strain curves obtained, Young＇s moduli of PEI （5-160 MPa） in three force regions are estimated according to the Hertz model The results indicate that PEI has excellent elasticity, which may contribute to its high efficiency as vectors in gene transfection.展开更多
A novel acrylate inimer, 2-（2-chloroacetyloxy） ethyl acrylate, was prepared by the reaction of 2-hydroxyethyl acrylate with chloroacetyl chloride in the presence of triethylamine. The self-condensing vinyl living ra...A novel acrylate inimer, 2-（2-chloroacetyloxy） ethyl acrylate, was prepared by the reaction of 2-hydroxyethyl acrylate with chloroacetyl chloride in the presence of triethylamine. The self-condensing vinyl living radical polymerization of the inimer was studied and the hyperbranched macromolecules containing ester linkages on their backbone were prepared. All the polymerization products were characterized by 1H NMR. The polymerization degree and the branching parameter were calculated based on the 1H NMR spectra. It has been shown that this inimer exhibits a very distinctive polymerization behavior. Similar to step-growth polymerization, the polymerization degree of the products formed increased exponentially during the early stage of the polymerization, and then the increasing rate slowed down. However, the inimer remained present throughout the polymerization consistent with conventional free radical polymerization. Also, if much longer polymerization time was used, the polymerization system would become gel due to the crosslinking reaction derived from radical-radical recombination. As a result of the unequal reactivity of -CH2Cl and >CHCl, an almost linear product was obtained at a molar ratio of bipy to inimer=0.05, while a relatively high ratio of bipy to inimer 1 favored the formation of the branched structure. The macromolecules formed at a high ratio of bipy to inimer 1 exhibited an excellent solubility in organic solvents such as acetone.展开更多
The idea of application from DNA information organization for providing the next generation super-computers has been proposed by lessons learned from nature. Thus, molecular environment of reserving information was co...The idea of application from DNA information organization for providing the next generation super-computers has been proposed by lessons learned from nature. Thus, molecular environment of reserving information was considered as succeeding generation of a mother-board project containing some subcategories with various applications. MERI, constructed based on the binary coding system using DNA synthesizer machine, enables retrievable reading of molecular structures using DNA sequencer machine. It has high capacity for reservation of information about 1.212 × 1011 Kb/cm2 with long-term stability. It can be used in various fields of science and technology regarding its high capacity, small size and safety measures.展开更多
Biological macromolecules, such as proteins and polysaccharides, are widely used in food systems because their interactions impart a desirable texture to food products. Plant proteins interact with food components via...Biological macromolecules, such as proteins and polysaccharides, are widely used in food systems because their interactions impart a desirable texture to food products. Plant proteins interact with food components via protein-protein and protein-polysaccharide associations, and the formation of a matrix, which can entrap other food components such as water, lipids and flavors. These networks provide structural integrity to food products and can serve as important functional ingredients in processed foods. Intermolecular interactions of typical polysaccharides result either in simple associations or in the form of a double or triple helix. The linear double helical segments may then interact to form a super junction and a three-dimensional gel network. The formation of these structural networks takes place during processing and involves the transformation from a liquid or viscous sol into a solid material with elastic properties. Interests in the behavior of mixed gels center on the prospects of enhanced flexibility in their mechanical and structural properties compared to those of pure gels. Findings on molecular interactions between plant proteins （e.g., soy, canola and pea proteins） and polysaccharides （e.g., guar gum, carrageenan, and pectin） allow for the modification of physical and textural characteristics of mixed biopolymers to meet desired functional property.展开更多
β-Glucans are biomacromolecules that present biological properties of medical and pharmacological interest, The chemical modification of the primary structure of these carbohydrate biopolymers is a way to enhance or ...β-Glucans are biomacromolecules that present biological properties of medical and pharmacological interest, The chemical modification of the primary structure of these carbohydrate biopolymers is a way to enhance or achieve new biological properties. Acetylated derivatives of （1→6）-β-D-glucan （lasiodiplodan） with different degrees of substitution （0.48, 0.66, 1.03 and 1.26） were obtained and characterized by infra-red and NMR （nuclear magnetic resonance） spectroscopy, thermal analysis, X-ray diffraction and antioxidant capacity. Acetylation was confirmed by FT-IR, and βC NMR spectroscopy. Thermal analysis indicated that unmodified lasiodiplodan and the O-acetylated β-glucan derivative of degree of substitution 0.48 presented three stages of mass-loss, whereas acetylated derivatives of DS （degree of substitution） of 0.66, 1.03 and 1.26 presented four stages of mass-loss. X-ray diffractograms demonstrated that both native and acetylated lasiodiplodan presented crystalline regions in an amorphous polymeric matrix. Scanning electron microscopy revealed that O-acetylation promoted morphologic changes in the biopolymer according to the DS. Acetylation also contributed to improve antioxidant capacity.展开更多
基金support from National Natural Science Foundation of China(32072267)supported by China Agriculture Research System of CRAS-14.
文摘Flaxseed lignan macromolecules(FLM)are a class of important secondary metabolites in fl axseed,which have been widely concerned due to their biological and pharmacological properties,especially for their antioxidative activity.For the composition and structure of FLM,our results confirmed that ferulic acid glycoside(FerAG)was directly ester-linked with herbacetin diglucoside(HDG)or pinoresinol diglucoside(PDG),which might determine the beginning of FLM biosynthesis.Additionally,p-coumaric acid glycoside(CouAG)might determine the end of chain extension during FLM synthesis in fl axseed.FLM exhibited higher antioxidative activity in polar systems,as shown by its superior 1,1-diphenyl-2-picrylhydrazyl(DPPH)free radical scavenging capacity compared to the 2,2’-azinobis(3-ehtylbenzothiazolin-6-sulfnic acid)(ABTS)cation free radical scavenging capacity in non-polar systems.Moreover,the antioxidative activity of FLM was found to be highly dependent on its composition and structure.In particular,it was positively correlated with the number of phenolic hydroxyl groups(longer FLM chains)and inversely related to the steric hindrance at the ends(lower levels of FerAG and CouAG).These fi ndings verifi ed the potential application of FLM in nonpolar systems,particularly in functional food emulsions。
基金financially supported the Key Research and Development Project of Anhui Province(2022a05020009)the Science and Technology Plan Project of Huangshan City(2021KC-05)the Engineering Research Project of Anhui Polytechnic University(HX-2021-09-007).
文摘Poly(isoprene-co-glycidyl methacrylate)epoxy macromolecules were synthesized via reversible addition-fragmentation chain transfer(RAFT)polymerization to act as interfacial mediators between talcum powder(Talc)and styrene-butadiene rubber(SBR)with the aim of improving the properties of SBR/Talc composites.The epoxy macromolecules were uniformly dispersed on the surface of Talc using the spray-drying method.Subse-quently,the modified Talc was utilized in the preparation of SBR composites.During hot vulcanization,isoprene double bonds could directly graft onto the rubber skeleton.Simultaneously,the epoxy groups opened the ring and formed covalent bonds with silanol.The interfacial covalent bonds were found to significantly enhance the dispersion of Talc and the interfacial interactions between SBR and Talc,as evidenced by scanning electron microscopy,cross-linking density measurements,and rubber processing analyzer tests.Differential scanning calorimetry results indicated that the number of interfacial covalent bonds and the content of glassy layers in the composites increased with the rise in GMA content and modified Talc.At equivalent filler loadings,epoxy macromolecules with 20 wt%and 34 wt%GMA increased the tensile strength by 31%and 49%,respectively.Concerning viscoelastic properties,composites containing interfacial covalent bonds exhibited superior stress relaxation and stress softening properties.
基金the National Natural Science Foundation of China(Nos.U1832215 and U1832144)the Youth Innovation Promotion Association of Chinese Academy Science(No.2017319).
文摘The BL19U2 at the Shanghai Synchrotron Radiation Facility is a small-angle X-ray scattering beamline dedicated to structural studies pertaining to biological macromolecules in solution.The beamline has been officially opened to users in March 2015,and since then,a series of technological innovations has been developed to optimize beamline performance,thereby significantly improving the data collection efficiency and broadening the application scope of biological small-angle X-ray scattering.BL19U2 is ideal for the high-throughput screening of weakly scattered proteins,protein assemblies,nucleic acids,inorganic nanomaterials,and organic drug molecules.This paper describes the design and overview of the BL19U2 beamline.Versatile sample environments at the experimental station and some recent scientific highlights are presented.
基金financially supported by the National Key R&D Program of China (No. 2016YFA0200200)the National Natural Science Foundation of China (Nos. 51533008, 51703194,51873191, and 21805242)+3 种基金Hundred Talents Program of Zhejiang University (No. 188020*194231701/113)Key Research and Development Plan of Zhejiang Province (No. 2018C01049)Fujian Provincial Science and Technology Major Projects (No.2018HZ0001-2)Key Laboratory of Novel Adsorption and Separation Materials and Application Technology of Zhejiang Province (No. 512301-I21502)。
文摘Graphene oxide(GO), which consists of two-dimensional(2 D) sp^(2) carbon hexagonal networks and oxygen-contained functional groups, has laid the foundation of mass production and applications of graphene materials. Made by chemical oxidation of graphite, GO is highly dispersible or even solubilized in water and polar organic solvents, which resolves the hard problem of graphene processing and opens a door to wet-processing of graphene. Despite its defects, GO is easy to functionalize, dope, punch holes, cut into pieces, conduct chemical reduction, form lyotropic liquid crystal, and assemble into macroscopic materials with tunable structures and properties as a living building block. GO sheet has been viewed as a single molecule, a particle, as well as a soft polymer material. An overview on GO as a 2 D macromolecule is essential for studying its intrinsic properties and guiding the development of relevant subjects. This review mainly focuses on recent advances of GO sheets, from single macromolecular behavior to macro-assembled graphene material properties. The first part of this review offers a brief introduction to the synthesis of GO molecules. Then the chemical structure and physical properties of GO are presented, as well as its polarity in solvent and rheology behavior. Several key parameters governing the ultimate stability of GO colloidal behavior, including size, p H and the presence of cation in aqueous dispersions, are highlighted. Furthermore, the discovery of GO liquid crystal and functionalization of GO molecules have built solid new foundations of preparing highly ordered, architecture-tunable, macro-assembled graphene materials, including 1 D graphene fibers, 2 D graphene films, and 3 D graphene architectures. The GO-based composites are also viewed and the interactions between these target materials and GO are carefully discussed. Finally, an outlook is provided in this field, where GO is regarded as macromolecules, pointing out the challenges and opportunities that exist in the field. We hope that this review will be beneficial to the understanding of GO in terms of chemical structure,molecular properties, macro-assembly and potential applications, and encourage further development to extend its investigations from basic research to practical applications.
基金National Natural Science Foundation of China(Grant No.81573272)
文摘In the previous research, we found that anticancer agent LS-1-2 F could cause the vacuolation of tumor cells. Herein we investigated the effect of compound LS-1-2 F on the endocytosis of macromolecules, including fluorescence quantum dots, human serum albumin, single-stranded RNA, and monoclonal antibody, into tumor cells. We found that LS-1-2 F could accelerate the endocytosis of these large molecules by laser confocal microscope and flow cytometry. The effect of LS-1-2 F on the improvement of the internalization efficiency of Herceptin biosimilar was particularly significant. Promoting endocytosis will help increase the efficiency of liquid-phase drug uptake in drug-resistant cancer cells and could potentially facilitate the use of drugs in nanoparticle delivery vehicles.
文摘In the construction of biosensors, enzymes function as mediators converting biological signals generated by specific biological processes, into electrochemical signals. The ideology of bio-sensor design is retention of electron transfer activity of the enzyme utilizing superior interfacial architecture. In this work a Schiff-base macromolecule has been synthesized by reflux of 2, 3-diaminonaphthalene and pyrrole-2-carboxaldehyde starting materials. The Schiff-base ligand was subsequently complexed with FeCl2?4H2O under reflux, to produce the Fe-Schiff-base complex. The Schiff-base ligand and Fe-Schiff-base complex were characterized using nuclear magnetic resonance (NMR) spectroscopy, Ultra Violet/Visible (UV/Vis) spectroscopy, Fourier transfer infrared resonance (FTIR) and electron energy loss spectroscopy (EELS) to confirm the structure of the synthesis products. NMR spectroscopy confirmed the imide linkage of Schiff-base formation as two symmetrical peaks at 8.1 and 7.7 ppm respectively. Comparison of starting materials and product spectra by UV/Vis spectroscopy confirmed the disappearance of the diaminonaphthalene peak at 250 nm as evidence of complete conversion to product. FTIR spectroscopy of the Schiff-base ligand confirmed the formation of the imine bond at 1595 cm-1. EELS spectra comparing FeCl2?4H2O and the Fe-Schiff-base complex, showed good agreement in the energy loss profiles associated with changes to the electronic arrangement of Fe d-orbitals. EDS clearly identified a spectral band for Fe (7 - 8 eV) in the Fe-Schiff-base complex. Electrochemical evaluation of the Fe-Schiff-base complex was compared to the electrochemical signature of denatured cytochrome-C using cyclic voltammetry and square wave voltammetry. The Fe2+/Fe3+ quasi-reversible behavior for iron in the metallated complex was observed at -0.430 V vs. Ag/AgCl, which is consistent with reference values for iron in macromolecular structures.
文摘An encoding method has a direct effect on the quality and the representationof the discovered knowledge in data mining systems. Biological macromolecules are encoded by stringsof characters, called primary structures. Knowing that data mining systems usually use relationaltables to encode data, we have then to re-encode these strings and transform them into relationaltables. In this paper, we do a comparative study of the existing static encoding methods, that arebased on the Biologist know-how, and our new dynamic encoding one, that is based on the constructionof Discriminant and Minimal Substrings (DMS). Different classification methods are used to do thisstudy. The experimental results show that our dynamic encoding method is more efficient than thestatic ones, to encode biological macromolecules within a data mining perspective.
文摘1 Results Several methods have been elaborated in this laboratory allowing preparation of macromolecules with phosphodiester bonds,and having sequence of atoms similar as in the chains of biomacromolecules - nucleic or teichoic acids (TA),namely:-(C)n-O-PO-,where n=2 (for teichoic acids) or 3.These methods,to be discussed in the lecture,are based on the ring-opening polymerization,transesterification,and recently elaborated direct addition of phosphoric acid to diepoxides.For the first time an attempt h...
文摘According to literature,certain microorganism productions mediate biological effects.However,their beneficial characteristics remain unclear.Nowadays,scientists concentrate on obtaining natural materials from live creatures as new sources to produce innovative smart biomaterials for increasing tissue reconstruction in tissue engineering and regenerative medicine.The present review aims to introduce microorganism-derived biological macromolecules,such as pullulan,alginate,dextran,curdlan,and hyaluronic acid,and their available sources for tissue engineering.Growing evidence indicates that these materials can be used as biological material in scaffolds to enhance regeneration in damaged tissues and contribute to cosmetic and dermatological applications.These natural-based materials are attractive in pharmaceutical,regenerative medicine,and biomedical applications.This study provides a detailed overview of natural-based biomaterials,their chemical and physical properties,and new directions for future research and therapeutic applications.
文摘A model for describing the behavior of macromolecules in adsorbed layers is developed by introducing a concept of distribution density of layer thicknessU based on stochastic process and probabilistic statistics. The molecular behavior of layers adsorbed on clay particle surfaces is discussed; the random distribution and its statistics of the layer thickness are given by incorporating experimental results with an ionic polyelectrolyte with the molecular weight of 1.08 x 106and chain charged density of 0.254.
基金funded by the National Natural Science Foundation of China(Nos.91751202,41976101 and 41730530)Marine S&T Fund of Shandong Province for Pilot National Laboratory for Marine Science and Technology(Qingdao)(No.2018SDKJ0406-4).
文摘The Mariana Trench is the deepest location on earth and harbors unique microbial communities as evidenced by 16S rRNA gene amplicon and metagenomic sequencing.Obtaining culturable microorganisms from the Mariana Trench will contribute to a further understanding of hadal biogeochemical processes and act as a unique microbial reservoir with potential applications.Here,825 bacterial strains,identified by 16S rRNA gene sequencing,were isolated from 12 water depths(0-10,400 m)of the Mariana Trench with 2216E and R2A media at 4℃ or 28℃ on four cruises during 2015-2017.These bacteria belong to four phyla,nine classes,27 orders,45 families and 108 genera.Alphaproteobacteria,Gammaproteobacteria,Actinobacteria_c,Bacilli and Flavobacteriia were the most abundant classes,accounting for 37.9%,33.0%,11.8%,8.6%and 8.0%of the total bacterial isolates,respectively.2216E and R2A media were found to have a better selectivity to Bacilli and Flavobacteriia,respectively.Fifty strains were potential novel bacterial species with a 16S rRNA gene similarity<98.65%,and a higher percentage of novel strains were obtained from R2A than 2216E medium.Additionally,301(150 species)out of 354 strains(178 species)selected from each depth could degrade at least one of the ten kinds of macromolecules tested.These results indicate that there is a high diversity of culturable bacteria in the Mariana Trench and they can produce a variety of extracellular enzymes.Our study provides a valuable resource of microorganisms for investigating their biogeochemical roles in the Mariana Trench and for industrial applications.
基金financially supported by the innovation funding from Wei Qiao Group(Nos.H2872307 and H2872305)Fundamental Research Funds for the Central Universities and Graduate Student Innovation Fund of Donghua University(No.CUSF-DH-D-2024004)。
文摘Poly(ester amide)s(PEAs)attract much attention as a new kind of biodegradable polymers.However,the synthesis of PEAs with sequence-regulated chain structures is still complicated due to the multistep polymerization,high monomer purity,as well as the usage of organic solvents,which greatly inhibits its development and applications.Herein,a one-pot strategy without solvent was developed to synthesize the alternating PEA fromα,ω-amino alcohol and dicarboxylic acid by sequential polycondensation,where water was used as the controlling agent for amidation and esterification.Specifically,the amidation and esterification were controlled to proceed in turn by adding or removing water,realizing the one-pot preparation of alternating PEAs.The resultant PEA is characterized by^1H-and^(13)C-NMR,and its chain structure is confirmed to be highly quasi-alternating similar to alternating PEAs prepared by classical methods The evaluations from DSC and DMA demonstrate that the properties of quasi-alternating PEA(T_(m)=102℃,ΔH_(m)=30J·g^(-1))are far superior to those of random PEA(T_(m)=72℃,ΔH_(m)<1 J·g^(-1)).
文摘BACKGROUND Breast cancer brain metastasis(BCBM)is an advanced breast disease that is difficult to treat and is associated with a high risk of death.Patient prognosis is usually poor,with reduced quality of life.In this context,we report the case of a patient with HER-2-positive BCBM treated with a macromolecular mAb(ine-tetamab)combined with a small molecule tyrosine kinase inhibitor(TKI).CASE SUMMARY The patient was a 58-year-old woman with a 12-year history of type 2 diabetes.She was compliant with regular insulin treatment and had good blood glucose control.The patient was diagnosed with invasive carcinoma of the right breast(T3N1M0 stage IIIa,HER2-positive type)through aspiration biopsy of the ipsilateral breast due to the discovery of a breast tumor in February 2019.Immunohistochemistry showed ER(-),PR(-),HER-2(3+),and Ki-67(55-60%+).Preoperative neoadjuvant chemotherapy,i.e.,the AC-TH regimen(epirubicin,cyclophosphamide,docetaxel-paclitaxel,and trastuzumab),was administered for 8 cycles.She underwent modified radical mastectomy of the right breast in November 2019 and received tocilizumab targeted therapy for 1 year.Brain metastasis was found 9 mo after surgery.She underwent brain metastasectomy in August 2020.Immunohistochemistry showed ER(-)and PR.(-),HER-2(3+),and Ki-67(10-20%+).In November 2020,the patient experienced headache symptoms.After an examination,tumor recurrence in the original surgical region of the brain was observed,and the patient was treated with inetetamab,pyrotinib,and capecitabine.Whole-brain radiotherapy was recommended.The patient and her family refused radiotherapy for personal reasons.In September 2021,a routine examination revealed that the brain tumor was considerably larger.The original systemic treatment was continued and combined with intensity-modulated radiation therapy for brain metastases,followed by regular hospitalization and routine examinations.The patient’s condition is generally stable,and she has a relatively high quality of life.This case report demonstrates that in patients with BCBM and resistance to trastuzumab,inetetamab combined with pyrotinib and chemotherapy can prolong survival.CONCLUSION Inetetamab combined with small molecule TKI drugs,chemotherapy and radiation may be an effective regimen for maintaining stable disease in patients with BCBM.
基金financially supported by the National Natural Science Foundation of China(No.21734005)National Key R&D Program of China(No.2020YFA0711504).
文摘This review firstly gives an overview on the importance of crystallization in natural and synthetic polymers/macromolecules.Then it introduces the typical features that have been raised by chain-like macromolecules in crystallization,including anisotropic interactions in the thermodynamic driving forces,chain folding in the crystal morphologies,chemical confinement in the copolymer crystallization,and mechanical enhancement in the stretching processes.Four features separately cover the thermodynamics and the kinetics of polymer crystallization,as well as the crystallinity and the mechanical properties of semicrystalline polymers.The review ends up with how these features enhance specific functions of crystalline polymers,which demonstrates polymer crystallization as a challenging yet promising field in the future.
文摘Nephrolithiasis seems to be the result of crystal formation,aggregation and retention in the kidney during crystalluria.These processes have to occur within the short urinary transit time through the kidney being in the order of few minutes.Recently much work was done on rather qualitative aspects of nephrolithiasis like genetics,metabolism and morphology.In this review we try to provide some quantitative information on urinary supersaturation with respect to stone minerals,especially Ca oxalate(CaO x),on the formation and aggregation of Ca Ox crystals and on crystal retention in the kidney.The paper is centered on idiopathic Ca nephrolithiasis being the most frequent stone disease with only partially known pathogenesis.New aspects of the role of urinary macromolecules in stone formation and of the mechanism of crystal aggregation are provided.
基金Supported by the 100 Persons Project of the Chinese Academy of Sciences, the National Natural Science Foundation of China under Grant No 10474109, the Foundation of Ministry of Personnel of China.
文摘The elasticity of an individual polymer nanoparticle may be greatly different from that of the bulk one. Understanding the properties of individual particles such as elasticity and deformation under external forces is of great importance in controlling the final structures and functions of bulk materials. We study the compression properties of single polyethylenimine （PEI） particles using vibrating scanning polarization force microscopy. By controllably imaging PEI particles at different vibration amplitude set-point values, it is demonstrated that we can compress the single PEI nanoparticle with an atomic force microscopy tip in different loads. Based on the force-height and force-strain curves obtained, Young＇s moduli of PEI （5-160 MPa） in three force regions are estimated according to the Hertz model The results indicate that PEI has excellent elasticity, which may contribute to its high efficiency as vectors in gene transfection.
基金Supported by the National Natural Science Foundation of China(No. 2 980 40 0 6 ) and the Youth Foundation of Jiangsuprovince(No.BQ980 2 4)
文摘A novel acrylate inimer, 2-（2-chloroacetyloxy） ethyl acrylate, was prepared by the reaction of 2-hydroxyethyl acrylate with chloroacetyl chloride in the presence of triethylamine. The self-condensing vinyl living radical polymerization of the inimer was studied and the hyperbranched macromolecules containing ester linkages on their backbone were prepared. All the polymerization products were characterized by 1H NMR. The polymerization degree and the branching parameter were calculated based on the 1H NMR spectra. It has been shown that this inimer exhibits a very distinctive polymerization behavior. Similar to step-growth polymerization, the polymerization degree of the products formed increased exponentially during the early stage of the polymerization, and then the increasing rate slowed down. However, the inimer remained present throughout the polymerization consistent with conventional free radical polymerization. Also, if much longer polymerization time was used, the polymerization system would become gel due to the crosslinking reaction derived from radical-radical recombination. As a result of the unequal reactivity of -CH2Cl and >CHCl, an almost linear product was obtained at a molar ratio of bipy to inimer=0.05, while a relatively high ratio of bipy to inimer 1 favored the formation of the branched structure. The macromolecules formed at a high ratio of bipy to inimer 1 exhibited an excellent solubility in organic solvents such as acetone.
文摘The idea of application from DNA information organization for providing the next generation super-computers has been proposed by lessons learned from nature. Thus, molecular environment of reserving information was considered as succeeding generation of a mother-board project containing some subcategories with various applications. MERI, constructed based on the binary coding system using DNA synthesizer machine, enables retrievable reading of molecular structures using DNA sequencer machine. It has high capacity for reservation of information about 1.212 × 1011 Kb/cm2 with long-term stability. It can be used in various fields of science and technology regarding its high capacity, small size and safety measures.
文摘Biological macromolecules, such as proteins and polysaccharides, are widely used in food systems because their interactions impart a desirable texture to food products. Plant proteins interact with food components via protein-protein and protein-polysaccharide associations, and the formation of a matrix, which can entrap other food components such as water, lipids and flavors. These networks provide structural integrity to food products and can serve as important functional ingredients in processed foods. Intermolecular interactions of typical polysaccharides result either in simple associations or in the form of a double or triple helix. The linear double helical segments may then interact to form a super junction and a three-dimensional gel network. The formation of these structural networks takes place during processing and involves the transformation from a liquid or viscous sol into a solid material with elastic properties. Interests in the behavior of mixed gels center on the prospects of enhanced flexibility in their mechanical and structural properties compared to those of pure gels. Findings on molecular interactions between plant proteins （e.g., soy, canola and pea proteins） and polysaccharides （e.g., guar gum, carrageenan, and pectin） allow for the modification of physical and textural characteristics of mixed biopolymers to meet desired functional property.
文摘β-Glucans are biomacromolecules that present biological properties of medical and pharmacological interest, The chemical modification of the primary structure of these carbohydrate biopolymers is a way to enhance or achieve new biological properties. Acetylated derivatives of （1→6）-β-D-glucan （lasiodiplodan） with different degrees of substitution （0.48, 0.66, 1.03 and 1.26） were obtained and characterized by infra-red and NMR （nuclear magnetic resonance） spectroscopy, thermal analysis, X-ray diffraction and antioxidant capacity. Acetylation was confirmed by FT-IR, and βC NMR spectroscopy. Thermal analysis indicated that unmodified lasiodiplodan and the O-acetylated β-glucan derivative of degree of substitution 0.48 presented three stages of mass-loss, whereas acetylated derivatives of DS （degree of substitution） of 0.66, 1.03 and 1.26 presented four stages of mass-loss. X-ray diffractograms demonstrated that both native and acetylated lasiodiplodan presented crystalline regions in an amorphous polymeric matrix. Scanning electron microscopy revealed that O-acetylation promoted morphologic changes in the biopolymer according to the DS. Acetylation also contributed to improve antioxidant capacity.
