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Antibacterial mechanism of kojic acid and tea polyphenols against Escherichia coli O157:H7 through transcriptomic analysis 被引量:1
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作者 Yilin Lin Ruifei Wang +4 位作者 Xiaoqing Li Keren Agyekumwaa Addo Meimei Fang Yehui Zhang Yigang Yu 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期736-747,共12页
Escherichia coli O157:H7 is one of the major foodborne pathogenic bacterial that cause infectious diseases in humans.The previous found that a combination of kojic acid and tea polyphenols exhibited better activity ag... Escherichia coli O157:H7 is one of the major foodborne pathogenic bacterial that cause infectious diseases in humans.The previous found that a combination of kojic acid and tea polyphenols exhibited better activity against E.coli O157:H7 than using either alone.This study aimed to explore responses underlying the antibacterial mechanisms of kojic acid and tea polyphenols from the gene level.The functional enrichment analysis by comparing kojic acid and tea polyphenols individually or synergistically against E.coli O157:H7 found that acid resistance systems in kojic acid were activated,and the cell membrane and genomic DNA were destructed in the cells,resulting in“oxygen starvation”.The oxidative stress response triggered by tea polyphenols inhibited both sulfur uptake and the synthesis of ATP,which affected the bacteria's life metabolic process.Interestingly,we found that kojic acid combined with tea polyphenols hindered the uptake of iron that played an essential role in the synthesis of DNA,respiration,tricarboxylic acid cycle.The results suggested that the iron uptake pathways may represent a novel approach for kojic acid and tea polyphenols synergistically against E.coli O157:H7 and provided a theoretical basis for bacterial pathogen control in the food industry. 展开更多
关键词 Kojic acid Tea polyphenols Antibacterial mechanism Escherichia coli O157:H7 RNA-SEQ
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具有可生物降解、细胞相容、抗菌及生物膜控制的壳聚糖磺基甜菜碱衍生物薄膜生物材料的研究
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作者 Maoli Yin Yingfeng Wang +1 位作者 Xuehong Ren Tung-Shi Huang 《Engineering》 SCIE EI CAS CSCD 2024年第4期95-103,共9页
The purpose of this research was to develop a chitosan sulfobetaine(CS-SNCC)film via the solutioncasting method as a biodegradable antibacterial material for biomedical applications.Chitosan and monochloro-triazine su... The purpose of this research was to develop a chitosan sulfobetaine(CS-SNCC)film via the solutioncasting method as a biodegradable antibacterial material for biomedical applications.Chitosan and monochloro-triazine sulfobetaine were used as the raw materials for CS-SNCC preparation,and Fourier-transform infrared(FTIR),ultraviolet–visible(UV-Vis),energy-dispersive X-ray(EDX),and Xray photoelectron spectroscopy(XPS)spectra were used to characterize and analyze the structure of the synthesized CS-SNCC.Furthermore,the swelling property,thermal stability,biodegradability,cytocompatibility,and antibacterial properties of the CS-SNCC film were comprehensively investigated and compared with those of the chitosan film.The results for the film’s enzymatic biodegradation behavior show that the CS-SNCC film undergoes a weight loss of 45.54%after 21 days of incubation.In addition,the CS-SNCC film effectively resists bacterial adhesion,prevents the formation of bacteria biofilms,and exhibits high antibacterial activity,with inactivation rates of 93.43%for Escherichia coli and 91.00%for Staphylococcus aureus.Moreover,the CS-SNCC film shows good cellular activity and cytocompatibility according to the cytotoxicity results.Therefore,the prepared biodegradable,cytocompatible,antibacterial,and biofilm-controlling CS-SNCC film has potential for biomedical applications. 展开更多
关键词 CHITOSAN SULFOBETAINE ANTIBACTERIAL Biofilm-controlling Film
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LncRNA pol-lnc78 as a ceRNA regulates antibacterial responses via suppression of pol-miR-n199-3p-mediated SARM down-regulation in Paralichthys olivaceus
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作者 Xian-Hui Ning Bing Han +1 位作者 Ye Peng Shao-Wu Yin 《Zoological Research》 SCIE CSCD 2024年第1期25-35,共11页
Long non-coding RNAs(lncRNAs)function as key modulators in mammalian immunity,particularly due to their involvement in lncRNA-mediated competitive endogenous RNA(ceRNA)crosstalk.Despite their recognized significance i... Long non-coding RNAs(lncRNAs)function as key modulators in mammalian immunity,particularly due to their involvement in lncRNA-mediated competitive endogenous RNA(ceRNA)crosstalk.Despite their recognized significance in mammals,research on lncRNAs in lower vertebrates remains limited.In the present study,we characterized the first immune-related lncRNA(pol-lnc78)in the teleost Japanese flounder(Paralichthys olivaceus).Results indicated that pol-lnc78 acted as a ceRNA for pol-miR-n199-3p to target the sterile alpha and armadillo motif-containing protein(SARM),the fifth discovered member of the Toll/interleukin 1(IL-1)receptor(TIR)adaptor family.This ceRNA network regulated the antibacterial responses of flounder via the Toll-like receptor(TLR)signaling pathway.Specifically,SARM acted as a negative regulator and exacerbated bacterial infection by inhibiting the expression of inflammatory cytokines IL-1βand tumor necrosis factor-α(TNF-α).Pol-miR-n199-3p reduced SARM expression by specifically interacting with the 3’untranslated region(UTR),thereby promoting SARM-dependent inflammatory cytokine expression and protecting the host against bacterial dissemination.Furthermore,pol-lnc78 sponged pol-miR-n199-3p to ameliorate the inhibition of SARM expression.During infection,the negative regulators pol-lnc78 and SARM were significantly down-regulated,while pol-miR-n199-3p was significantly up-regulated,thus favoring host antibacterial defense.These findings provide novel insights into the mechanisms underlying fish immunity and open new horizons to better understand ceRNA crosstalk in lower vertebrates. 展开更多
关键词 LncRNA SARM miRNA ceRNA Antibacterial response
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Experimental and computational study of annealed nickel sulfide quantum dots for catalytic and antibacterial activity
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作者 Muhammad Ikram Sawaira Moeen +5 位作者 Ali Haider Anwar Ul-Hamid Haya Alhummiany Hamoud H.Somaily Souraya Goumri-Said Mohammed Benali Kanoun 《Nano Materials Science》 EI CAS CSCD 2024年第3期355-364,共10页
This research investigates the hydrothermal synthesis and annealing duration effects on nickel sulfide(NiS_(2) quantum dots(QDs)for catalytic decolorization of methylene blue(MB)dye and antimicrobial efficacy.QD size ... This research investigates the hydrothermal synthesis and annealing duration effects on nickel sulfide(NiS_(2) quantum dots(QDs)for catalytic decolorization of methylene blue(MB)dye and antimicrobial efficacy.QD size increased with longer annealing,reducing catalytic activity.UV–vis,XRD,TEM,and FTIR analyses probed optical structural,morphological,and vibrational features.XRD confirmed NiS2's anorthic structure,with crystallite size growing from 6.53 to 7.81 nm during extended annealing.UV–Vis exhibited a bathochromic shift,reflecting reduced band gap energy(Eg)in NiS_(2).TEM revealed NiS_(2)QD formation,with agglomerated QD average size increasing from 7.13 to 9.65 nm with prolonged annealing.Pure NiS_(2) showed significant MB decolorization(89.85%)in acidic conditions.Annealed NiS_(2) QDs demonstrated notable antibacterial activity,yielding a 6.15mm inhibition zone against Escherichia coli(E.coli)compared to Ciprofloxacin.First-principles computation supported a robust interaction between MB and NiS_(2),evidenced by obtained adsorption energies.This study highlights the nuanced relationship between annealing duration,structural changes,and functional properties in NiS_(2)QDs,emphasizing their potential applications in catalysis and antibacterial interventions. 展开更多
关键词 NiS_(2) ANTIBACTERIAL quantum dots DYE degradation DFT
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New Antibacterial Dihydropyrones Induced by Co-Culture of Penicillium crustosum PRB-2 and Penicillium citrinum HDN11-186
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作者 YU Guihong ZHOU Luning +1 位作者 WU Guangwei LI Dehai 《Journal of Ocean University of China》 CAS CSCD 2024年第1期216-220,共5页
Two new dihydropyrones,rhytismatones C(1)and D(2),and a known compound,penicillenol A1(3),were isolated from the co-culture broth of the deep-sea-derived fungus Penicillium crustosum PRB-2 and Suaeda salsa-derived end... Two new dihydropyrones,rhytismatones C(1)and D(2),and a known compound,penicillenol A1(3),were isolated from the co-culture broth of the deep-sea-derived fungus Penicillium crustosum PRB-2 and Suaeda salsa-derived endophytic fungus Peni-cillium citrinum HDN11-186.Their structures were elucidated through comprehensive analysis of nuclear magnetic resonance(NMR)spectra and mass spectra.The absolute configurations of new compounds were determined by calculating the electronic circular di-chroism(ECD)spectrum.UPLC-MS data showed that compounds 1–3 could only be detected in the media of co-culture,suggesting new biosynthetic pathways were activated in the co-cultured fungi.Compound 1 showed obvious antibacterial activities against Pro-teus sp.MMBC-1002 and Bacillus subtilis MMBC-1004 with minimum inhibitory concentration(MIC)both at 25μmolL^(-1). 展开更多
关键词 CO-CULTURE Penicillium crustosum Penicillium citrinum dihydropyrones antibacterial activity
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Antimicrobial,antibiofilm,angiogenesis,anti-inflammatory,and wound healing activities of zinc nanoparticles green synthesized using Ferula macrecolea extract
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作者 Sultan F.Alnomasy 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第6期259-268,共10页
Objective:To assess the antimicrobial,antibiofilm,anti-inflammatory,angiogenic,and wound healing activities of zinc nanoparticles(ZNPs)green synthesized using Ferula macrecolea extract.Methods:The green synthesis was ... Objective:To assess the antimicrobial,antibiofilm,anti-inflammatory,angiogenic,and wound healing activities of zinc nanoparticles(ZNPs)green synthesized using Ferula macrecolea extract.Methods:The green synthesis was conducted using the precipitation method.Then,the minimum inhibitory concentration(MIC),minimum bactericidal concentration(MBC),and minimum biofilm inhibition concentration 50%(MBIC50)of ZNPs against Staphylococcus aureus(S.aureus)and Pseudomonas aeruginosa(P.aeruginosa)were evaluated.The effects of ZNPs on the gene expressions of Staphylococcus spp.[intracellular adhesion A(icaA)and D(icaD)]and P.aeruginosa(rhlI and rhlR)were investigated using quantitative real-time PCR.In addition,the effects of ZNPs on wound healing,angiogenesis,and anti-inflammatory markers were assessed.Results:The green-synthesized ZNPs demonstrated significant antimicrobial efficacy against S.aureus and P.aeruginosa.The biofilm formation in S.aureus and P.aeruginosa was also inhibited by ZNPs with MBIC50 values of 3.30μg/mL and 2.08μg/mL,respectively.Additionally,ZNPs downregulated the expression of biofilm-related genes icaA,icaD,rhlI,and rhlR in the tested bacteria.They also demonstrated promising in vitro wound healing effects by promoting fibroblast cell proliferation and wound closure in a dose-dependent manner.A significant increase in the expression of HLA-G5 and VEGF-A genes as well as a marked decrease in the expression of NF-κB,IL-1β,and TNF-αgenes were observed in cells treated with ZNPs compared to the control group(P<0.05).Conclusions:ZNPs display promising antibacterial effects against S.aureus and P.aeruginosa and wound-healing effects by inhibiting biofilm formation,inducing angiogenesis,and reducing inflammation.However,further studies must be conducted to specify the accurate mechanisms of action and toxicity of ZNPs. 展开更多
关键词 Wound healing Antibacterial ANGIOGENESIS NANOMEDICINE Ferula macrecolea Inflammation
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Molecular Characterization and Antibacterial Activity of a G-Type Lysozyme in Yellow Drum(Nibea albiflora)
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作者 XIAO Yao LI Jiacheng +2 位作者 TIAN Qianqian WU Baolan HAN Fang 《Journal of Ocean University of China》 CAS CSCD 2024年第2期477-486,共10页
Lysozyme(EC3.2.1.17)plays an important role in the immune response;as a nonspecific immune factor,it can resist causative agents.Lysozyme can be divided into c-type and g-type in fish.In a previous study,through genom... Lysozyme(EC3.2.1.17)plays an important role in the immune response;as a nonspecific immune factor,it can resist causative agents.Lysozyme can be divided into c-type and g-type in fish.In a previous study,through genome-wide association analysis,the g-type lysozyme gene,which is named NaLyg in yellow drum(Nibea albiflora),was found to be a key candidate gene for disease resistance in response to Vibrio harveyi infection.The cDNA of NaLyg was 1025 bp,including four exons and three introns,and its open reading frame(ORF)had a full-length of 582 bp,encoding 193 amino acids.NaLyg was found to be conserved during evolution through bioinformatic analyses.The NaLyg protein possessed a sugar binding domain and three catalytic sites,including Glu71,Asp84 and Asp101.Quantitative qRT-PCR results confirmed that NaLyg gene mRNA was visibly increased after V.harveyi infection.The NaLyg protein purified by prokaryotic expression killed some gram-negative bacterial pathogens by inducing cell wall destruction,including V.harveyi,Aeromonas hydrophila and Edwardsiella tarda.Moreover,the NaLyg protein killed two gram-positive bacteria,Bacillus subtilis and Staphylococcus aureus.Taken together,the experimental results suggested that the NaLyg protein of N.albiflora played an important role in fighting bacterial infections. 展开更多
关键词 Nibea albiflora innate immunity Vibrio harveyi g-type lysozyme antibacterial activity
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A drug-loaded flexible substrate improves the performance of conformal cortical electrodes
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作者 Rongrong Qin Tian Li +7 位作者 Yifu Tan Fanqi Sun Yuhao Zhou Ronghao Lv Xiaoli You Bowen Ji Peng Li Wei Huang 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第4期399-412,共14页
Cortical electrodes are a powerful tool for the stimulation and/or recording of electrical activity in the nervous system.However,the inevitable wound caused by surgical implantation of electrodes presents bacterial i... Cortical electrodes are a powerful tool for the stimulation and/or recording of electrical activity in the nervous system.However,the inevitable wound caused by surgical implantation of electrodes presents bacterial infection and inflammatory reaction risks associated with foreign body exposure.Moreover,inflammation of the wound area can dramatically worsen in response to bacterial infection.These consequences can not only lead to the failure of cortical electrode implantation but also threaten the lives of patients.Herein,we prepared a hydrogel made of bacterial cellulose(BC),a flexible substrate for cortical electrodes,and further loaded antibiotic tetracycline(TC)and the anti-inflammatory drug dexamethasone(DEX)onto it.The encapsulated drugs can be released from the BC hydrogel and effectively inhibit the growth of Gram-negative and Gram-positive bacteria.Next,therapeutic cortical electrodes were developed by integrating the drug-loaded BC hydrogel and nine-channel serpentine arrays;these were used to record electrocorticography(ECoG)signals in a rat model.Due to the controlled release of TC and DEX from the BC hydrogel substrate,therapeutic cortical electrodes can alleviate or prevent symptoms associated with the bacterial infection and inflammation of brain tissue.This approach facilitates the development of drug delivery electrodes for resolving complications caused by implantable electrodes. 展开更多
关键词 ANTIBACTERIAL ANTI-INFLAMMATORY Drug loading Cortical electrodes Bacterial cellulose hydrogel
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Oxygen vacancy boosting Fenton reaction in bone scaffold towards fighting bacterial infection
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作者 Cijun Shuai Xiaoxin Shi +2 位作者 Feng Yang Haifeng Tian Pei Feng 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第1期296-311,共16页
Bacterial infection is a major issue after artificial bone transplantation due to the absence of antibacterial function of bone scaffold,which seriously causes the transplant failure and even amputation in severe case... Bacterial infection is a major issue after artificial bone transplantation due to the absence of antibacterial function of bone scaffold,which seriously causes the transplant failure and even amputation in severe cases.In this study,oxygen vacancy(OV)defects Fe-doped Ti O2(OV-FeTiO2)nanoparticles were synthesized by nano TiO2and Fe3O4via high-energy ball milling,which was then incorporated into polycaprolactone/polyglycolic acid(PCLGA)biodegradable polymer matrix to construct composite bone scaffold with good antibacterial activities by selective laser sintering.The results indicated that OV defects were introduced into the core/shell-structured OV-FeTiO2nanoparticles through multiple welding and breaking during the high-energy ball milling,which facilitated the adsorption of hydrogen peroxide(H2O2)in the bacterial infection microenvironment at the bone transplant site.The accumulated H2O2could amplify the Fenton reaction efficiency to induce more hydroxyl radicals(·OH),thereby resulting in more bacterial deaths through·OH-mediated oxidative damage.This antibacterial strategy had more effective broad-spectrum antibacterial properties against Gram-negative Escherichia coli(E.coli)and Gram-positive Staphylococcus aureus(S.aureus).In addition,the PCLGA/OV-FeTiO2scaffold possessed mechanical properties that match those of human cancellous bone and good biocompatibility including cell attachment,proliferation and osteogenic differentiation. 展开更多
关键词 bacterial infection bone scaffold selective laser sintering Fenton reaction antibacterial properties
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Mussel-inspired Methacrylic Gelatin-dopamine/Ag Nanoparticles/Graphene Oxide Hydrogels with Improved Adhesive and Antibacterial Properties for Applications as Wound Dressings
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作者 宿正楠 HU Yanru +5 位作者 MENG Lihui OUYANG Zhiyuan LI Wenchao ZHU Fang XIE Bin 吴庆知 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期512-521,共10页
A novel strategy was developed to prepare the methacrylic gelatin-dopamine(GelMA-DA)/Ag nanoparticles(NPs)/graphene oxide(GO) composite hydrogels with good biocompatibility,mechanical properties,and antibacterial acti... A novel strategy was developed to prepare the methacrylic gelatin-dopamine(GelMA-DA)/Ag nanoparticles(NPs)/graphene oxide(GO) composite hydrogels with good biocompatibility,mechanical properties,and antibacterial activity.Mussel-inspired DA was utilized to modify the GelMA molecules,which imparts good adhesive performance to the hydrogels.GO,interfacial enhancer,not only improves mechanical properties of the hydrogels,but also provides anchor sites for loading Ag NPs through numerous oxygencontaining functional groups on the surface.The experimental results show that the GelMA/Ag NPs/GO hydrogels have good biocompatibility,and exhibit a swelling rate of 202±16%,the lap shear strength of 147±17 kPa,and compressive modulus of 136±53 kPa,in the case of the Ag NPs/GO content of 2 mg/mL.Antibacterial activity of the hydrogels against both gram-negative and gram-positive bacteria is dependent on the Ag NPs/GO content derived from the release of Ag^(+).Furthermore,the GelMA/Ag NPs/GO hydrogels possess good adhesive ability,which is resistant to highly twisted state when stuck on the surface of pigskin.These results demonstrate promising potential of the GelMA-DA/Ag NPs/GO hydrogels as wound dressings for biomedical applications in clinical and emergent treatment. 展开更多
关键词 GelMA dopamine graphene oxide adhesion antibacterial ability
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Bio-Based Waterborne Poly(Vanillin-Butyl Acrylate)/MXene Coatings for Leather with Desired Warmth Retention and Antibacterial Properties
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作者 Jianzhong Ma Li Ma +3 位作者 Lei Zhang Wenbo Zhang Qianqian Fan Buxing Han 《Engineering》 SCIE EI CAS CSCD 2024年第5期250-263,共14页
This study presents a solvent-free,facile synthesis of a bio-based green antibacterial agent and aromatic monomer methacrylated vanillin(MV)using vanillin.The resulting MV not only imparted antibacterial properties to... This study presents a solvent-free,facile synthesis of a bio-based green antibacterial agent and aromatic monomer methacrylated vanillin(MV)using vanillin.The resulting MV not only imparted antibacterial properties to coatings layered on leather,but could also be employed as a green alternative to petroleum-based carcinogen styrene(St).Herein,MV was copolymerized with butyl acrylate(BA)to obtain waterborne bio-based P(MV-BA)miniemulsion via miniemulsion polymerization.Subsequently,MXene nanosheets with excellent photothermal conversion performance and antibacterial properties,were introduced into the P(MV-BA)miniemulsion by ultrasonic dispersion.During the gradual solidification of P(MV-BA)/MXene nanocomposite miniemulsion on the leather surface,MXene gradually migrated to the surface of leather coatings due to the cavitation effect of ultrasonication and amphiphilicity of MXene,which prompted its full exposure to light and bacteria,exerting the maximum photothermal conversion efficiency and significant antibacterial efficacy.In particular,when the dosage of MXene nanosheets was 1.4 wt%,the surface temperature of P(MV-BA)/MXene nanocomposite miniemulsioncoated leather(PML)increased by about 15℃ in an outdoor environment during winter,and the antibacterial rate against Escherichia coli and Staphylococcus aureus was nearly 100%under the simulated sunlight treatment for 30 min.Moreover,the introduction of MXene nanosheets increased the air permeability,water vapor permeability,and thermal stability of these coatings.This study provides a new insight into the preparation of novel,green,and waterborne bio-based nanocomposite coatings for leather,with desired warmth retention and antibacterial properties.It can not only realize zerocarbon heating based on sunlight in winter,reducing the use of fossil fuels and greenhouse gas emissions,but also improve ability to fight off invasion by harmful bacteria,viruses,and other microorganisms. 展开更多
关键词 MXene nanosheets VANILLIN Styrene substitute Leather coating Photothermal conversion Warmth retention Antibacterial properties
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Discovery and structure-activity relationship studies of novel tetrahydro-β-carboline derivatives as apoptosis initiators for treating bacterial infections
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作者 Shanshan Su Hongwu Liu +7 位作者 Junrong Zhang Puying Qi Yue Ding Ling Zhang Linli Yang Liwei Liu Xiang Zhou Song Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1259-1273,共15页
Developing and excavating new agrochemicals with highly active and safe is an important tactic for protecting crop health and food safety.In this paper,to discover the new bactericide candidates,we designed,prepared a... Developing and excavating new agrochemicals with highly active and safe is an important tactic for protecting crop health and food safety.In this paper,to discover the new bactericide candidates,we designed,prepared a new type of1,2,3,4-tetrahydro-β-carboline(THC)derivatives and evaluated the in vitro and in vivo bioactivities against the Xanthomonas oryzae pv.oryzae(Xoo),Xanthomonas axonopodis pv.citri(Xac),and Pseudomonas syringae pv.actinidiae(Psa).The in vitro bioassay results exhibited that most title molecules possessed good activity toward the three plant pathogenic bacteria,the compound A17 showed the most active against Xoo and Xac with EC50 values of 7.27 and 4.89 mg mL^(-1)respectively,and compound A8 exhibited the best inhibitory activity against Psa with EC50value of 4.87 mg mL^(-1).Pot experiments showed that compound A17 exhibited excellent in vivo antibacterial activities to manage rice bacterial leaf blight and citrus bacterial canker,with protective efficiencies of 52.67 and 79.79%at 200 mgmL^(-1),respectively.Meanwhile,compound A8 showed good control efficiency(84.31%)against kiwifruit bacterial canker at 200 mg mL^(-1).Antibacterial mechanism suggested that these compounds could interfere with the balance of the redox system,damage the cell membrane,and induce the apoptosis of Xoo cells.Taken together,our study revealed that tetrahydro-β-carboline derivatives could be a promising candidate model for novel broadspectrum bactericides. 展开更多
关键词 tetrahydro-β-carboline derivatives antibacterial activity ROS cell apoptosis
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Dual-functional poly(2-methyl-2-oxazoline)/poly(2-(dimethylamine)ethyl methacrylate)mixed brushes with switchable protein adsorption and antibacterial properties
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作者 Kang He Liangyu Zhu Yanmei Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期19-30,共12页
Herein,binary mixed brushes consisting of poly(2-methyl-2-oxazoline)(PMOXA)and poly(2-(dimethylamine)ethyl methacrylate)(PDMAEMA)with different chain lengths were fabricated by successive grafting of NH_(2)-terminated... Herein,binary mixed brushes consisting of poly(2-methyl-2-oxazoline)(PMOXA)and poly(2-(dimethylamine)ethyl methacrylate)(PDMAEMA)with different chain lengths were fabricated by successive grafting of NH_(2)-terminated PMOXA and SH-terminated PDMAEMA onto polydopamine-anchored substrates.The mixed-brush coating was characterized by variable-angle spectroscopic ellipsometry,X-ray photoelectron spectroscopy,Fourier transform infrared spectroscopy,zeta potential measurements,water contact angle,and atomic force microscopy.The mixed brushes showed tunable surface charge,wettability,and surface roughness,depending on the degree of PDMAEMA swelling under varying pH and ionic strength(Ⅰ).Then the adsorption behaviors of pepsin,bovine serum albumin(BSA),γ-globulin,and lysozyme,four very different proteins with regard to isoelectric point,on the mixed brushes coating were studied by using fluorescence microscopy and surface plasmon resonance.When the chain length of PDMAEMA was about twice as long as PMOXA,the mixed brushes not only had high adsorption capacity for pepsin,BSA,and y-globulin but also had a desorption efficiency of 86.9%,87.1%,and 93.5%,respectively.It is explained that electrostatic attraction between the protonated PDMAEMA and positively charged acidic proteins(pepsin and BSA,whose isoelectric points were below the pK_(a) of PDMAEMA)would drive the intensive adsorption(at pH 3,I=10^(-3)mol·L^(-1)for pepsin,and pH 5,I=10^(-5)mol·L^(-1)for BSA),while desorption was dominated by the hydrophilic PMOXA when PDMAEMA was shrinking(at pH 7,I=10^(-1)mol·L^(-1)for pepsin,and pH 9,I=10^(-1)mol·L^(-1)for BSA).Furthermore,the isoelectric precipitation led to the adsorption of neutral protein(γ-globulin,whose isoelectric point was near the pK_a of PDMAEMA)at pH 7,I=10^(-5)mol·L^(-1),while electrostatic repulsion and antifouling PMOXA triggered the desorption of y-globulin at pH 3,I-10^(-1)mol·L^(-1).However,alkaline protein(lysozyme,whose isoelectric point was higher than the pK_(a) of PDMAEMA)exhibited slight adsorption on PMOXA/PDMAEMA mixed brushes under test conditions,regardless of whether PMOXA or PDMAEMA occupied the outermost layer.The antibacterial property of the mixed brushes against Escherichia coli was investigated.PMOXA/PDMAEMA mixed brushes showed significant bactericidal activity at pH 3,I=10^(-3)mol·L^(-1),while the rinse of pH 9,I=10^(-1)mol·L^(-1)solution could remove most of the residual bacteria.This work not only enables controlled adsorption of proteins with different isoelectric points but also ensures that the surface of the coating is minimized from bacterial contamination. 展开更多
关键词 Switchable conformation transition Controllable protein adsorption Mixed brushes Isoelectric point Antibacterial surface
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Additively manufactured Ti–Ta–Cu alloys for the next-generation load-bearing implants
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作者 Amit Bandyopadhyay Indranath Mitra +4 位作者 Sushant Ciliveri Jose D Avila William Dernell Stuart B Goodman Susmita Bose 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第1期353-374,共22页
Bacterial colonization of orthopedic implants is one of the leading causes of failure and clinical complexities for load-bearing metallic implants. Topical or systemic administration of antibiotics may not offer the m... Bacterial colonization of orthopedic implants is one of the leading causes of failure and clinical complexities for load-bearing metallic implants. Topical or systemic administration of antibiotics may not offer the most efficient defense against colonization, especially in the case of secondary infection, leading to surgical removal of implants and in some cases even limbs. In this study, laser powder bed fusion was implemented to fabricate Ti3Al2V alloy by a 1:1 weight mixture of CpTi and Ti6Al4V powders. Ti-Tantalum(Ta)–Copper(Cu) alloys were further analyzed by the addition of Ta and Cu into the Ti3Al2V custom alloy. The biological,mechanical, and tribo-biocorrosion properties of Ti3Al2V alloy were evaluated. A 10 wt.% Ta(10Ta) and 3 wt.% Cu(3Cu) were added to the Ti3Al2V alloy to enhance biocompatibility and impart inherent bacterial resistance. Additively manufactured implants were investigated for resistance against Pseudomonas aeruginosa and Staphylococcus aureus strains of bacteria for up to 48 h. A 3 wt.% Cu addition to Ti3Al2V displayed improved antibacterial efficacy, i.e.78%–86% with respect to CpTi. Mechanical properties for Ti3Al2V–10Ta–3Cu alloy were evaluated, demonstrating excellent fatigue resistance, exceptional shear strength, and improved tribological and tribo-biocorrosion characteristics when compared to Ti6Al4V. In vivo studies using a rat distal femur model revealed improved early-stage osseointegration for alloys with10 wt.% Ta addition compared to CpTi and Ti6Al4V. The 3 wt.% Cu-added compositions displayed biocompatibility and no adverse infammatory response in vivo. Our results establish the Ti3Al2V–10Ta–3Cu alloy’s synergistic effect on improving both in vivo biocompatibility and microbial resistance for the next generation of load-bearing metallic implants. 展开更多
关键词 TI6AL4V load-bearing implants additive manufacturing 3D printing antibacterial performance
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Ag-doped CNT/HAP nanohybrids in a PLLA bone scaffold show significant antibacterial activity
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作者 Cijun Shuai Xiaoxin Shi +3 位作者 Kai Wang Yulong Gu Feng Yang Pei Feng 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第2期105-120,共16页
Bacterial infection is a major problem following bone implant surgery.Moreover,poly-l-lactic acid/carbon nanotube/hydroxyapatite(PLLA/CNT/HAP)bone scaffolds possess enhanced mechanical properties and show good bioacti... Bacterial infection is a major problem following bone implant surgery.Moreover,poly-l-lactic acid/carbon nanotube/hydroxyapatite(PLLA/CNT/HAP)bone scaffolds possess enhanced mechanical properties and show good bioactiv-ityregardingbonedefectregeneration.Inthisstudy,wesynthesizedsilver(Ag)-dopedCNT/HAP(CNT/Ag-HAP)nanohybrids via the partial replacing of calcium ions(Ca2+)in the HAP lattice with silver ions(Ag+)using an ion doping technique under hydrothermal conditions.Specifically,the doping process was induced using the special lattice structure of HAP and the abundant surface oxygenic functional groups of CNT,and involved the partial replacement of Ca2+in the HAP lattice by doped Ag+as well as the in situ synthesis of Ag-HAP nanoparticles on CNT in a hydrothermal environment.The result-ing CNT/Ag-HAP nanohybrids were then introduced into a PLLA matrix via laser-based powder bed fusion(PBF-LB)to fabricate PLLA/CNT/Ag-HAP scaffolds that showed sustained antibacterial activity.We then found that Ag+,which pos-sesses broad-spectrum antibacterial activity,endowed PLLA/CNT/Ag-HAP scaffolds with this activity,with an antibacterial effectiveness of 92.65%.This antibacterial effect is due to the powerful effect of Ag+against bacterial structure and genetic material,as well as the physical destruction of bacterial structures due to the sharp edge structure of CNT.In addition,the scaffold possessed enhanced mechanical properties,showing tensile and compressive strengths of 8.49 MPa and 19.72 MPa,respectively.Finally,the scaffold also exhibited good bioactivity and cytocompatibility,including the ability to form apatite layers and to promote the adhesion and proliferation of human osteoblast-like cells(MG63 cells). 展开更多
关键词 Ag-doped Carbon nanotube/hydroxyapatite(CNT/HAP) Antibacterial properties Bone scaffold
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Recent progress on Sn_(3)O_(4)nanomaterials for photocatalytic applications
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作者 Xin Yu Congcong Li +3 位作者 Jian Zhang Lili Zhao Jinbo Pang Longhua Ding 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第2期231-244,共14页
Tin(IV)oxide(Sn_(3)O_(4))is layered tin and exhibits mixed valence states.It has emerged as a highly promising visible-light pho-tocatalyst,attracting considerable attention.This comprehensive review is aimed at provi... Tin(IV)oxide(Sn_(3)O_(4))is layered tin and exhibits mixed valence states.It has emerged as a highly promising visible-light pho-tocatalyst,attracting considerable attention.This comprehensive review is aimed at providing a detailed overview of the latest advance-ments in research,applications,advantages,and challenges associated with Sn_(3)O_(4)photocatalytic nanomaterials.The fundamental con-cepts and principles of Sn_(3)O_(4)are introduced.Sn_(3)O_(4)possesses a unique crystal structure and optoelectronic properties that allow it to ab-sorb visible light efficiently and generate photoexcited charge carriers that drive photocatalytic reactions.Subsequently,strategies for the control and improved performance of Sn_(3)O_(4)photocatalytic nanomaterials are discussed.Morphology control,ion doping,and hetero-structure construction are widely employed in the optimization of the photocatalytic performance of Sn_(3)O_(4)materials.The effective imple-mentation of these strategies improves the photocatalytic activity and stability of Sn_(3)O_(4)nanomaterials.Furthermore,the review explores the diverse applications of Sn_(3)O_(4)photocatalytic nanomaterials in various fields,such as photocatalytic degradation,photocatalytic hydro-gen production,photocatalytic reduction of carbon dioxide,solar cells,photocatalytic sterilization,and optoelectronic sensors.The discus-sion focuses on the potential of Sn_(3)O_(4)-based nanomaterials in these applications,highlighting their unique attributes and functionalities.Finally,the review provides an outlook on the future development directions in the field and offers guidance for the exploration and de-velopment of novel and efficient Sn_(3)O_(4)-based nanomaterials.Through the identification of emerging research areas and potential avenues for improvement,this review aims to stimulate further advancements in Sn_(3)O_(4)-based photocatalysis and facilitate the translation of this promising technology into practical applications. 展开更多
关键词 PHOTOCATALYSIS Sn_(3)O_(4)nanomaterials building heterostructures antibacterial therapy water splitting
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Superwetting Ag/α-Fe_(2)O_(3) anchored mesh with enhanced photocatalytic and antibacterial activities for efficient water purification
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作者 Jiakai Li Changpeng Lv +5 位作者 Jiajia Song Xiaoling Zhang Xizhen Huang Yingzhuo Ma Haijie Cao Na Liu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期89-103,共15页
Superwetting materials have drawn unprecedented attention in the treatment of oily wastewater due to their preferable anti-fouling property and selective oil/water separation.However,it is still a challenge to fabrica... Superwetting materials have drawn unprecedented attention in the treatment of oily wastewater due to their preferable anti-fouling property and selective oil/water separation.However,it is still a challenge to fabricate multifunctional and environmentally friendly materials,which can be stably applied to purify the actual complicated wastewater.Here,a Ag/Ag/α-Fe_(2)O_(3) heterostructure anchored copper mesh was intentionally synthesized using a facile two-step hydrothermal method.The resultant mesh with superhydrophilicity and underwater superoleophobicity was capable of separating various oil/water mixtures with superior separation efficiency and high permeationflux driven by gravity.Benefiting from the joint effects of the smaller band gap of Ag/α-Fe_(2)O_(3) heterojunction,inherent antibacterial capacity of Ag/α-Fe_(2)O_(3) and Ag nanoparticles,favorable conductive substrate,as well as the hierarchical structure with superwettability,such mesh presented remarkably enhanced degradation capability toward organic dyes under visible light irradiation and antibacterial activity against both Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)compared with the pure Ag/α-Fe_(2)O_(3) coated mesh.Impressively,the mesh exhibited bifunctional water purification performance,in which organic dyes were eliminated simultaneously from water during oil/water separation in onefiltration process.More importantly,this mesh behaved exceptional chemical resistance,mechanical stability and long-term reusability.Therefore,this material with multifunctional integration may hold promising potential for steady water purification in practice. 展开更多
关键词 Superwetting Ag/α-Fe_(2)O_(3)heterostructure Enhanced photocatalytic and antibacterial activities Water purification Long-term reusability
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Semisynthetic Derivatives of Sissotrin Isolated from Trifolium baccarinii Chiov. (Fabaceae) and Evaluation of Their Antibacterial Activities
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作者 Donald Léonel Feugap Tsamo Cyrille Ngoufack Tagousop +2 位作者 Arnaud Joseph Nguetse Dongmo Laurence Voutquenne-Nazabadioko David Ngnokam 《Advances in Biological Chemistry》 CAS 2024年第1期27-39,共13页
Starting from sissotrin (1), a natural isoflavonoid isolated from Trifolium baccarinii (Fabaceae), one new semisynthetic derivative, 6-nitrobiochanin A (1b) and two known derivatives, 8-nitrobiochanin A (1a) and 2&quo... Starting from sissotrin (1), a natural isoflavonoid isolated from Trifolium baccarinii (Fabaceae), one new semisynthetic derivative, 6-nitrobiochanin A (1b) and two known derivatives, 8-nitrobiochanin A (1a) and 2",3",4",6"-tetraacetylsissotrin (1c) have been obtained after performing nitration and acetylation reactions. Their structures were assigned after interpretation of their spectrometric (HR-ESI-MS) and spectroscopic (NMR 1D and 2D) data and by comparison with those reported in the literature. The substrate as well as the semisynthetic derivatives were evaluated for their antibacterial activities against six strains. The results reveal that they are inactive or weakly active on the strains tested with the exception of 8-nitrobiochanin A (1a) which showed moderate activity (MIC = 62.5 μg∙mL<sup>−1</sup>) on Staphylococcus aureus ATCC 43300. 展开更多
关键词 Trifolium baccarinii ISOFLAVONOID NITRATION ACETYLATION Antibacterial Activity
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Practice of Perioperative Rational Use of Antibacterial Drugs Based on Drug Pathway
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作者 Changkai ZHOU Fanbo JING +1 位作者 Haijun QU Jing GAO 《Medicinal Plant》 2024年第2期57-60,64,共5页
[Objectives]To establish a new management model for rational use of perioperative antibacterial drugs in surgical departments.[Methods]Based on evidence-based medicine,the department s drug pathway was formulated,and ... [Objectives]To establish a new management model for rational use of perioperative antibacterial drugs in surgical departments.[Methods]Based on evidence-based medicine,the department s drug pathway was formulated,and the new mode of rational drug use control was established by using fine pharmaceutical technology intervention,and the intervention effect was evaluated by the intensity of antibacterial drug use,per capita drug costs and the proportion of drugs.[Results]After adopting drug pathway in departments,the intensity of antibacterial drug use,per capita drug costs and the proportion of drugs decreased significantly,and the effect of rational drug use control was remarkable.[Conclusions]The drug pathway provides a new management and control mode for the rational use of perioperative antibacterial drugs in surgical departments of hospitals.Thus,it is worthy of popularization and application. 展开更多
关键词 Perioperative period Antibacterial drugs Drug pathway Rational drug use Management model
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Green Synthesis of Silver Nanoparticles Using Aqueous Orange and Lemon Peel Extract and Evaluation of Their Antimicrobial Properties
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作者 Amra Bratovcic Amna Dautovic 《Advances in Nanoparticles》 CAS 2024年第2期11-28,共18页
Green synthesis of silver nanoparticles (AgNPs) using aqueous extracts of orange and lemon peels, as a reducing agent, and silver nitrate salts as a source of silver ions is a promising field of research due to the ve... Green synthesis of silver nanoparticles (AgNPs) using aqueous extracts of orange and lemon peels, as a reducing agent, and silver nitrate salts as a source of silver ions is a promising field of research due to the versatility of biomedical applications of metal nanoparticles. In this paper, AgNPs were synthetized at different reaction parameters such as the type and concentration of the extracts, metal salt concentration, temperature, speed stirring, and pH. The antibacterial properties of the obtained silver nanoparticles against E. coli, as well as the physical and chemical characteristics of the synthesized silver nanoparticles, were investigated. UV-Vis spectroscopy was used to confirm the formation of AgNPs. In addition to green biogenic synthesis, chemical synthesis of silver nanoparticles was also carried out. The optimal temperature for extraction was 65˚C, while for the synthesis of AgNPs was 35˚C. The synthesis is carried out in an acidic environment (pH = 4.7 orange and pH = 3.8 lemon), neutral (pH = 7) and alkaline (pH = 10), then for different concentrations of silver nitrate solution (0.5 mM - 1 mM), optimal time duration of the reaction was 60 min and optimal stirring speed rotation was 250 rpm on the magnetic stirrer. The physical properties of the synthesized silver nanoparticles (conductivity, density and refractive index) were also studied, and the passage of laser light through the obtained solution and distilled water was compared. Positive inhibitory effect on the growth of new Escherichia coli colonies have shown AgNPs synthesized at a basic pH value and at a 0.1 mM AgNO<sub>3</sub> using orange or lemon peel extract, while for a 0.5 mM AgNO<sub>3 </sub>using lemon peel extract. 展开更多
关键词 Green Synthesis Silver Nanoparticles Orange and Lemon Peel Extract Antibacterial Activity Escherichia coli
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