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Effects of friction stir processing and nano-hydroxyapatite on the microstructure,hardness,degradation rate and in-vitro bioactivity of WE43 alloy for biomedical applications
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作者 Bo Wu Farazila Yusof +5 位作者 Fuguo Li Huan Miao A.R.Bushroa Mohd Ridha Bin Muhamad Irfan Anjum Badruddin Mahmoud Z.Ibrahim 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期209-224,共16页
Nowadays,magnesium alloys are emerging in biomedical implants for their similar properties to natural bones.However,the rapid degradation of magnesium alloys in biological media hinders successful implantation.Refinem... Nowadays,magnesium alloys are emerging in biomedical implants for their similar properties to natural bones.However,the rapid degradation of magnesium alloys in biological media hinders successful implantation.Refinement of microstructure,as well as reinforcement particles can significantly improve the degradation rate.In this work,multi-pass friction stir processing(FSP)was proposed to synthesize WE43/nano-hydroxyapatite(n HA)surface composite,the microstructure,reinforced particle distribution,micro-hardness,corrosion behavior and in-vitro bioactivity were studied.The subsequent FSP passes of WE43 alloy and WE43/n HA composite refined the grain size which was reduced by 94.29%and 95.92%(2.63 and 1.88μm,respectively)compared to base metal after three passes.This resulted in increasing the microhardness by 120%(90.86 HV0.1)and 135%(105.59 HV0.1)for the WE43 and WE43-n HA,respectively.It is found that increasing FSP passes improved the uniform distribution of n HA particles within the composite matrix which led to improved corrosion resistance and less degradation rate.The corrosion rate of the FSPed WE43/n HA composite after three passes was reduced by 38.2%(4.13 mm/year)and the degradation rate was reduced by 69.7%(2.87 mm/y).This is attributed to secondary phase(Mg24Y5and Mg41Nd5)particle fragmentation and redistribution,as well as a homogeneous distribution of n HA.Additionally,the growing Ca-P and Mg(OH)2layer formed on the surface represented a protective layer that reduced the degradation rate.The wettability test revealed a relatively hydrophilic surface with water contact angle of 49.1±2.2°compared to 71.2±2.1°for base metal.Also,biomineralization test showed that apatite layer grew after immersion 7d in simulated body fluid with atomic ratio of Ca/P 1.60 approaching the stoichiometric ratio(1.67)indicating superior bioactivity of FSPed WE43/n HA composite after three passes.These results raise that the grain refinement by FSP and introduction of n HA particles significantly improved the degradation rate and in-vitro bioactivity of WE43 alloy for biomedical applications. 展开更多
关键词 Friction stir processing Magnesium-based composite NANO-HYDROXYAPATITE Corrosion behavior In-vitro bioactivity
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Research Progress on Structure and Bioactivity of Longan Polysaccharide
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作者 Xiaolong Ji Shuli Zhang +5 位作者 Xueyuan Jin Xin Yuan Siqi Zhang Xudan Guo Fengcheng Shi Yanqi Liu 《Journal of Renewable Materials》 SCIE EI 2023年第4期1631-1642,共12页
Longan originates from southern China and has high nutritional and health value.Recent phytochemistry and pharmacology studies have shown that polysaccharides are a main bioactive component of longan.Longan polysaccha... Longan originates from southern China and has high nutritional and health value.Recent phytochemistry and pharmacology studies have shown that polysaccharides are a main bioactive component of longan.Longan polysaccharides possess antioxidant,anti-aging,anti-tumor,immunomodulatory,and other bioactivities.Hot-water extraction,ethanol precipitation,and ultrasonic extraction are generally used to extract water-soluble longan polysaccharides.However,the relationship between the structure and bioactivity of longan polysaccharides remains unclear,requiring further investigation.The aim of this review is to evaluate the current literature focusing on the extraction,purification,structural characterization,and biological activity of longan polysaccharides.We believe that this review would provide a useful bibliography for further innovation and a basis for using longan polysaccharides in functional food. 展开更多
关键词 LONGAN POLYSACCHARIDES structural characterization bioactivity
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Synthesis, Characterization and Bioactivity of Complexes of Rare Earth with Bis-Schiff Base from Furoylpyrazolone 被引量:4
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作者 李锦州 李刚 于文锦 《Journal of Rare Earths》 SCIE EI CAS CSCD 2000年第3期233-236,共4页
Eleven new complexes of rare earths with bis Schiff base derived from N,N’ bis[(1 phenyl 3 methyl 5 oxo 4 pyrazolinyl)α furylmethylidyne] ethylenediimine ((HPMαFP) 2en) were synthesized. On the basis of elemental a... Eleven new complexes of rare earths with bis Schiff base derived from N,N’ bis[(1 phenyl 3 methyl 5 oxo 4 pyrazolinyl)α furylmethylidyne] ethylenediimine ((HPMαFP) 2en) were synthesized. On the basis of elemental analysis and molar conductance, a general formula of the complexes, [RE(HPMαFP) 2 en(NO 3) 2]NO 3 (RE=La, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Yb,Y), was given. The complexes were characterized by IR, UV visible, 1H NMR, 13 C NMR and fluorescence. The results show that the bis Schiff base is a quadridentate ligand and the rare earth ions exhibit coordination of eight in the complexes. The antibacterial experiments indicate that they have high antibacterial activities against S. aureus, B. subtillis, E. coli, E.carotovora, C. flaccumfaciens. 展开更多
关键词 RARE earths furoylpyrazolone BIS SCHIFF BASE bioactivity
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Influence of mental stress on platelet bioactivity 被引量:6
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作者 Pia Koudouovoh-Tripp Barbara Sperner-Unterweger 《World Journal of Psychiatry》 SCIE 2012年第6期134-147,共14页
It is well established that various mental stress conditions contribute, or at least influence, underlying pathophysiological mechanisms in somatic, as well as in psychiatric disorders; blood platelets are supposed to... It is well established that various mental stress conditions contribute, or at least influence, underlying pathophysiological mechanisms in somatic, as well as in psychiatric disorders; blood platelets are supposed to represent a possible link in this respect. The anculeated platelets are the smallest corpuscular elements circulating in the human blood. They display different serotonergic markers which seem to reflect the central nervous serotonin metabolism. They are known as main effectors in haematological processes but recent research highlights their role in the innate and adaptive immune system. Platelets are containing a multitude of pro-inflammatory and immune-modulatory bioactive compounds in their granules and are expressing immune-competent surface markers. Research gives hint that platelets activation and reactivity is increased by mental stress. This leads to enhanced cross talk with the immune system via paracrine secretion, receptor interaction and formation of platelet leucocyteaggregates. Recently it has been demonstrated that the immune system can have a remarkable impact in the development of psychiatric disorders. Thereforeplatelets represent an interesting research area in psychiatry and their role as a possible biomarker has been investigated. We review the influence of mental stress on what is termed platelet bioactivity in this article, which subsumes the mainly immune-modulatory activity of platelets in healthy volunteers, elderly persons with chronic care-giving strain, patients with cardiovascular diseases who are prone to psychosocial stress, as well as in patients with posttraumatic stress disorder. Research data suggest that stress enhances platelet activity, reactivity and immune-modulatory capacities. 展开更多
关键词 MENTAL STRESS CAREGIVING strain POSTTRAUMATIC STRESS disorder Cardiovascular disease SEROTONIN PLATELET activation PLATELET bioactivity
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Isolation and characterization of anti-diabetic component(bioactivity-guided fractionation) from Ocimum sanctum L.(Lamiaceae) aerial part 被引量:2
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作者 Raju Patil Ravindra Patil +1 位作者 Bharati Ahirwar Dheeraj Ahirwar 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第4期278-282,共5页
Objective:To isolate and characterize antidiabetic component(bioactivity-guided fractionation) from hydro alcoholic extract of Ocimum sanctum(O.sanctum) aerial part.Methods:Ten fractions(F1 - F10) were isolated ... Objective:To isolate and characterize antidiabetic component(bioactivity-guided fractionation) from hydro alcoholic extract of Ocimum sanctum(O.sanctum) aerial part.Methods:Ten fractions(F1 - F10) were isolated from hydro alcoholic extract of O.sanctum aerial part by column chromatography.All the fractions Fl to F10 were screened for antidiabetic activity in alloxan induced diabetic rats by estimating serum glucose level and lipid parameters.The isolated bioactive component was elucidated on the basis of extensive spectroscopic(UV,IR,MS,<sup>1</sup>H and <sup>13</sup>C NMR) data analysis.Results:The bioactive fraction(F5) was found to be potent antidiabetic by ameliorating glucose and lipid parameters(total cholesterol,triglycerides,low and high density lipoprotein cholesterol).The extensive spectroscopic data analysis reveals that,the isolated bioactive compound elucidated as tetracyclic triterpenoid[16-Hydroxy-4,4,10,13-tetramethyl- 17-(4-methyI-pentyl)-hexadecahydro-cyclopenta[a]phenanthren-3-one].Conclusions:Our present study concluded that,tetracyclic triterpenoid isolated from aerial part of O.sanctum has a great anti-diabetic potential. 展开更多
关键词 OCIMUM sanctum Diabetes bioactivity GUIDED FRACTIONATION
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Recombinant amelogenin regulates the bioactivity of mouse cementoblasts in vitro 被引量:3
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作者 Sema S.Hakki S.Buket Bozkurt +3 位作者 Emre Türkay Michel Dard Nuhan Purali Werner Gotz 《International Journal of Oral Science》 SCIE CAS CSCD 2018年第2期117-126,共10页
Amelogenin(AMG) is a cell adhesion molecule that has an important role in the mineralization of enamel and regulates events during dental development and root formation. The purpose of the present study was to investi... Amelogenin(AMG) is a cell adhesion molecule that has an important role in the mineralization of enamel and regulates events during dental development and root formation. The purpose of the present study was to investigate the effects of recombinant human AMG(rhAMG) on mineralized tissue-associated genes in cementoblasts. Immortalized mouse cementoblasts(OCCM-30)were treated with different concentrations(0.1, 1, 10, 100, 1 000, 10 000, 100 000 ng · mL^(-1)) of recombinant human AMG(rhAMG)and analyzed for proliferation, mineralization and mRNA expression of bone sialoprotein(BSP), osteocalcin(OCN), collagen type I(COL I), osteopontin(OPN), runt-related transcription factor 2(Runx2), cementum attachment protein(CAP), and alkaline phosphatase(ALP) genes using quantitative RT-PCR. The dose response of rhAMG was evaluated using a real-time cell analyzer.Total RNA was isolated on day 3, and cell mineralization was assessed using von Kossa staining on day 8. COL I, OPN and lysosomalassociated membrane protein-1(LAMP-1), which is a cell surface binding site for amelogenin, were evaluated using immunocytochemistry. F-actin bundles were imaged using confocal microscopy. rhAMG at a concentration of 100 000 ng · mL^(-1) increased cell proliferation after 72 h compared to the other concentrations and the untreated control group. rhAMG(100 000 ng · mL^(-1)) upregulated BSP and OCN mRNA expression levels eightfold and fivefold, respectively. rhAMG at a concentration of 100 000 ng · mL^(-1) remarkably enhanced LAMP-1 staining in cementoblasts. Increased numbers of mineralized nodules were observed at concentrations of 10 000 and 100 000 ng · mL^(-1) rhAMG. The present data suggest that rhAMG is a potent regulator of gene expression in cementoblasts and support the potential application of rhAMG in therapies aimed at fast regeneration of damaged periodontal tissue. 展开更多
关键词 AMG Recombinant amelogenin regulates the bioactivity mouse cementoblasts vitro OCN
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Effects of Traditional Chinese Medicinal Plants on Antiinsulin Resistance Bioactivity of DXMS-Induced Insulin Resistant HepG2 Cells 被引量:4
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作者 Jun-Zeng Ma Li-Xin Yang +7 位作者 Xiao-Ling Shen Ji-Huan Qin Li-Lan Deng Selena Ahmed Hong-Xi Xu Da-Yuan Xue Jiang-Xia Ye Gang Xu 《Natural Products and Bioprospecting》 CAS 2014年第4期197-206,共10页
Medicinal plants have a long history of use in China to treat diabetic symptoms.Ancient Chinese medical manuscripts and ethnobotanical surveys document plant remedies that continue to be actively used in China for the... Medicinal plants have a long history of use in China to treat diabetic symptoms.Ancient Chinese medical manuscripts and ethnobotanical surveys document plant remedies that continue to be actively used in China for the treatment of diabetic symptoms.Based on a systematic ancient Chinese medical manuscripts review in combination with ethnobotanical survey,16 medicinal plants for the traditional treatment of diabetic symptoms were identified for the evaluation of anti-insulin resistance bioactivity.The biological activity of 16 medicinal plants was tested on dexamethasone(DXMS)-induced insulin resistant HepG2 cells.The result shows that 11 of the 16 medicinal plants enhanced glucose uptake of DXMS-induced insulin resistant HepG2 cells,thereby demonstrating their ability to increase insulin sensitivity,other five medicinal plants including Astragalus membranaceus were found ineffective.The study shows that ancient Chinese medical manuscripts and ethnobotanical surveys on plants for the prevention and treatment of diabetic symptoms provide a promising knowledge base for drug discovery to mitigate the global diabetes epidemic. 展开更多
关键词 Traditional medicinal plants Diabetes Anti-insulin resistance bioactivity DXMS-induced insulin resistant HepG2 cells
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Conceptual Density Functional Theory Study of the Chemical Reactivity Properties and Bioactivity Scores of the Leu-Enkephalin Opioid Peptide Neurotransmitter 被引量:2
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作者 Juan Frau Norma Flores-Holguín Daniel Glossman-Mitnik 《Computational Molecular Bioscience》 2019年第1期13-26,共14页
The SMD solvation model (Solvation Model based on the Density) and eight density functionals, CAM-B3LYP, LC-ωPBE, M11, MN12SX, N12SX, ωB97, ωB97X, and ωB97XD, were assessed in link with the Def2TZVP basis set for ... The SMD solvation model (Solvation Model based on the Density) and eight density functionals, CAM-B3LYP, LC-ωPBE, M11, MN12SX, N12SX, ωB97, ωB97X, and ωB97XD, were assessed in link with the Def2TZVP basis set for the calculation of the structure of the Leu-Enkephalin Opioid Peptide Neurotransmitter as well as their molecular properties. Through the Conceptual Density Functional Theory (CDFT), the entire chemical descriptors for the system were calculated. The active regions of the molecules necessary for electrophilic, nucleophilic and radical attacks were chosen through linking them with the corresponding Fukui functions. Furthermore, the prediction of the pKa value for the peptide is done with great accuracy as well as the ability of the studied molecule in acting as an efficient inhibitor of the formation of Advanced Glycation Endproducts (AGEs), which comprises of a useful knowledge for the development of drugs for preventing Alzheimer, Diabetes and Parkinson diseases. Lastly, the bioactivity scores for the studied peptides are predicted via various methodologies. 展开更多
关键词 LEU-ENKEPHALIN OPIOID NEUROTRANSMITTERS Computational Chemistry CONCEPTUAL DFT bioactivity SCORES
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Synthesis and bioactivity of a novel series of 3,6-disubstituted 1,2,4-triazolo[3,4-b]-1,3,4-thiadiazoles 被引量:1
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作者 Li, Ying Jun Liu, Li Jun +2 位作者 Jin, Kun Xu, Yong Ting Sun, Su Qin 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第3期293-296,共4页
A novel series of 3,6-disubstituted 1,2,4-triazolo[3,4-b]-1,3,4-thiadiazoles were synthesized by the condensation of 4-amino-5- [2-(4-chlorophenoxymethylbenzimidazole)-1-methylene]-3-mercapto-1,2,4-triazole with vario... A novel series of 3,6-disubstituted 1,2,4-triazolo[3,4-b]-1,3,4-thiadiazoles were synthesized by the condensation of 4-amino-5- [2-(4-chlorophenoxymethylbenzimidazole)-1-methylene]-3-mercapto-1,2,4-triazole with various(un)substituted aromatic acids in the presence of phosphorous oxychloride.These compounds were investigated for their inhibitory activity to E.coli methionine aminopeptidase(EcMetAP1).Some of the tested compounds showed significant inhibitory activity. 展开更多
关键词 Triazolo-thiadiazoles SYNTHESIS bioactivity
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A Bioactivity Versus Ethnobotanical Survey of Medicinal Plants from Nigeria, West Africa 被引量:1
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作者 Lydia L.Lifongo Conrad V.Simoben +2 位作者 Fidele Ntie-Kang Smith B.Babiaka Philip N.Judson 《Natural Products and Bioprospecting》 CAS 2014年第1期1-19,共19页
Traditional medicinal practices play a key role in health care systems in countries with developing economies.The aim of this survey was to validate the use of traditional medicine within local Nigerian communities.In... Traditional medicinal practices play a key role in health care systems in countries with developing economies.The aim of this survey was to validate the use of traditional medicine within local Nigerian communities.In this review,we examine the ethnobotanical uses of selected plant species from the Nigerian flora and attempt to correlate the activities of the isolated bioactive principles with known uses of the plant species in African traditional medicine.Thirty-three(33)plant species were identified and about 100 out of the 120 compounds identified with these plants matched with the ethnobotanical uses of the plants. 展开更多
关键词 African traditional medicine bioactivity ETHNOBOTANY Medicinal plants NIGERIA
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Chemical Reactivity Properties, Drug-Likeness Features and Bioactivity Scores of the Cholecystokinin Peptide Hormone 被引量:1
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作者 Norma Flores-Holguín Juan Frau Daniel Glossman-Mitnik 《Computational Molecular Bioscience》 2019年第2期41-47,共7页
Five density functionals, CAM-B3LYP, LC-ωPBE, MN12SX, N12SX and ωB97XD, in connection with the Def2TZVP basis set were assessed together with the SMD solvation model for the calculation of the molecular and chemical... Five density functionals, CAM-B3LYP, LC-ωPBE, MN12SX, N12SX and ωB97XD, in connection with the Def2TZVP basis set were assessed together with the SMD solvation model for the calculation of the molecular and chemical reactivity properties of the Cholecystokinin peptide hormone (CCK-8) in the presence of water. All the chemical reactivity descriptors for the systems were calculated via Conceptual Density Functional Theory (CDFT). The potential bioavailability and druggability as well as the bioactivity scoresfor CCK-8 were predicted through different methodologies already reported in the literature which have been previously validated during the study of different peptidic systems. The conclusion was that the CCK-8 peptide will be moderately bioactive regarding all the interactions. 展开更多
关键词 CHOLECYSTOKININ Peptide HORMONE (CCK-8) Conceptual DFT Chemical Reactivity DRUG-LIKENESS FEATURES bioactivity SCORES
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EXPRESSING HUMAN MATURED BRAIN-DERIVED NEUROTROPHIC FACTOR GENE IN E.Coli AND DETERMINING ITS BIOACTIVITY 被引量:1
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作者 马东亮 任惠民 +3 位作者 胡海涛 刘勇 杨广笑 王全颖 《Academic Journal of Xi'an Jiaotong University》 2001年第1期9-12,共4页
Objective Expressing the human matured brain-derived neurotrophic factor (mBDNF) gene in E. Coli and determining its bioactivity. Methods The resulting gene of mBDNF was subcloned into the EcoRI-BamHI site or the expr... Objective Expressing the human matured brain-derived neurotrophic factor (mBDNF) gene in E. Coli and determining its bioactivity. Methods The resulting gene of mBDNF was subcloned into the EcoRI-BamHI site or the expression vector plasmid pBV220. The ligation products were used to transform the competent E. Coli DH5a. The proteins or mBDNF were experessed by temperature inducing. The expression products were dealed with solubilizing inclusion bodies and refolding protein. It was introduced into the embryonic chicken DRG to test whether the expressed mBDNF is a biologically active protein. Results The recombinant plasmid pBV/mBDNF was success- fully constructed. By temperature inducing, under the control of the bacteriophage λPL promoter, the experessed mBDNF protein was a 14Kd non-fusion protein,which existed in E. Coli as inclusion bodies. The size or expressed mBDNF is identical to the prediction. Bioactivity of the products was proved that it could support the cell survival and neurite growth in the primary cultures of embryonic 8-day-old chicken DRG neurons as compared to control. Conclusion Tke mBDNF gene can be expressed bioactively in E. Coli. 展开更多
关键词 human matured brain-derived neurotrophic factor (mBDNF) molecular subcloning EXPRESSION bioactivity
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Isolated Endophytic Fungi from the Plant <i>Curcuma longa</i>and Their Potential Bioactivity—A Review 被引量:1
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作者 Kazi Jannatul Ferdous Farhana Afroz +2 位作者 Md. Rakibul Islam Md. Abdul Mazid Md. Hossain Sohrab 《Pharmacology & Pharmacy》 2019年第5期244-270,共27页
Endophytes (both fungi and bacteria) represent a treasure house for bioactive compounds such as anticancer, immunomodulatory, antioxidant, antiparasitic, insecticidal etc. for use in the pharmaceutical and agrochemica... Endophytes (both fungi and bacteria) represent a treasure house for bioactive compounds such as anticancer, immunomodulatory, antioxidant, antiparasitic, insecticidal etc. for use in the pharmaceutical and agrochemical industries. Endophytic population is greatly influenced by climatic conditions and location where the host plant grows. Curcuma longa L. (Turmeric) is a medicinal plant belonging to the Zingiberaceae family that is usually used as spice and preservative. Traditionally it is used to treat various conditions and symptoms such as digestive disorders, arthritis, cardiovascular conditions, cancer, bacterial infections etc. In recent times, there have been different discoveries on endophytic fungi and their biological activity from C. longa. But there is no comprehensive review on endophytic fungi of C. longa. The aim of this review is to analyze the published report based on the endophytic fungi to provide for the first time an updated information about their isolation from different tissues, their biological activities including the phytochemistry of C. longa. This will lead the way to forecast the missing link for future research work. 展开更多
关键词 CURCUMA longa ENDOPHYTES COMPOUNDS bioactivity
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Diversity and Bioactivity of Cultivable Animal Fecal Actinobacteria 被引量:1
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作者 Yi Jiang Li Han +5 位作者 Xiu Chen Min Yin Dan Zheng Yong Wang Shumei Qiu Xueshi Huang 《Advances in Microbiology》 2013年第1期1-13,共13页
Microbial symbionts play important roles in food digestion and absorption, immunity, pathogens resistance, and health maintaining of their hosts by coevolution. To provide new sources for discovering new leader compou... Microbial symbionts play important roles in food digestion and absorption, immunity, pathogens resistance, and health maintaining of their hosts by coevolution. To provide new sources for discovering new leader compounds of drugs, the diversity and bioactivities of cultivable actinobacteria from animal feces have been studied. 31 species of animal fecal samples were collected fromYunnanWildAnimalPark. The purified cultures of actinobacteria were isolated from these samples by using 5 media. The 16S rRNA gene sequences of 528 selected strains were determined, the phylogenetic analysis was carried out, and anti-microbial and anti-tumor activities were determined. 35 genera (including a new genus, Enteractinococcus) of actinobacteria from the 31 species of animal feces were identified. Some strains had high anti-tumor and antimicrobial activities. More than 50 secondary metabolites were isolated and identified, a novel bioactive macrolactam polyketide glycoside, Sannastatin, was found. Nine fecal streptomycete strains were fermented respectively, blended to the microbial manure, and used to prophylaxis and treatment of soil-borne disease of notoginseng in field. The incidence rate of the disease was lower 81% than agricultural chemicals. Fecal actinobacteria, a possibility as a new source for discovering drug leader, agricultural chemicals and other industry products, will be discussed. 展开更多
关键词 ACTINOBACTERIA DIVERSITY bioactivity ANIMAL FECES
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Effects of H_2O_2 pretreatment on surface characteristics and bioactivity of NaOH-treated NiTi shape memory alloy
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作者 储成林 胡涛 +6 位作者 周俊 浦跃朴 尹立红 董寅生 林萍华 钟志源 朱剑豪 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2006年第6期1295-1300,共6页
The effects of H2O2 pretreatment on the surface characteristics and bioactivity of NaOH-treated NiTi shape memory alloy(SMA)were investigated by scanning electron microscopy,X-ray diffraction,X-ray photoelectron spect... The effects of H2O2 pretreatment on the surface characteristics and bioactivity of NaOH-treated NiTi shape memory alloy(SMA)were investigated by scanning electron microscopy,X-ray diffraction,X-ray photoelectron spectroscopy,Raman spectra,Fourier transform infrared spectroscopy as well as a simulated body fluid(SBF)soaking test.It is found that the H2O2 pretreatment can lead to the direct creation of more Ti—OH groups and the decrease in the amount of Ni2O3,Na2TiO3 and remnant NiTi phases on the surfaces of bioactive NiTi SMA prepared by NaOH treatment.As a result,the induction period of apatite formation is shortened by dispensing with the slow kinetic formation process of Ti—OH groups via an exchange of Na+ ions from Na2TiO3 phase with H3O+ ions in SBF,which indicates that the bioactivity of NaOH-treated NiTi SMA can be further improved by the H2O2 pretreatment. 展开更多
关键词 shape memory alloy(SMA) NITI NAOH treatment surface structure bioactivity H2O2 PRETREATMENT
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Phylogenetic diversity and bioactivity of culturable deepsea-derived fungi from Okinawa Trough
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作者 Xiaoyong ZHANG Yiyang LI +2 位作者 Zonghe YU Xiao LIANG Shuhua QI 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2021年第3期892-902,共11页
Deep-sea sediments are now recognized as a home for rich and largely microbial community.Recently,it has been believed in an increasing number of studies that bacteria could be abundant in deepsea sediments of many ty... Deep-sea sediments are now recognized as a home for rich and largely microbial community.Recently,it has been believed in an increasing number of studies that bacteria could be abundant in deepsea sediments of many types;however,fungi in deep-sea sediments remain relatively unknown.The phylogenetic diversity and bioactivity of culturable deep-sea-derived fungi from Okinawa Trough sediments were investigated in traditional method combined with fungal identification of molecular biology in this study.A total of 76 isolates belonged to 15 fungal taxa were recovered in a harsh condition of low nutrient and low temperature,indicating that the fungal communities in deep-sea sediments from Okinawa Trough were relatively abundant and diversified.Aspergillus,Cladosporium,and Penicillium were the dominant fungal genera,while Mycosphaerella,Purpureocillium,and Schizophyllum were relatively rare in the deep-sea sediments from Okinawa Trough.Among the six genera recovered,Mycosphaerella was firstly recovered from deep-sea sediments in this study.Moreover,about 75%of the extracts from the 15 fungal representative isolates displayed distinct bioactivity against at least one indicator bacterium or marine macrofouler,emphasizing the potentials of these deep-sea-derived fungi from Okinawa Trough as producers of bioactive metabolites.Notably,isolates Cladosporium oxysporum SCSIO z001 and Penicillium citrinum SCSIO z049 displayed a wide spectrum of bioactivities,isolates Cladosporium cladosporioides SCSIO z015,Cladosporium sphaerospermum SCSIO z030,and Penicillium verruculosum SCSIO z007 exhibited a strong anti-bacterial-growth activity,and isolate Penicillium chrysogenum SCSIO z062 displayed a strong anti-larval-settlement activity.These results suggest that these isolates deserved further study as potential sources of novel bioactive metabolites. 展开更多
关键词 deep-sea-derived fungi phylogenetic diversity bioactivity Okinawa Trough hydrothermal vents
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Chemical Composition and Bioactivity of Lippia adoensis Hochst ex.Walp(Verneneaceae) Leaf Essential Oil Against Callosobruchus maculatus Fabricius(Coleoptera: Chrysomelidae)
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作者 Babarinde Samuel Adelani Oladoye Sunday Olusegun +1 位作者 Adesina Gabriel Olulakin Adebayo Moses Adeolu 《Journal of Northeast Agricultural University(English Edition)》 CAS 2016年第4期8-14,共7页
Essential oil(EO) of Nigeria-grown Lippia adoensis leaf was analyzed using gas chromatography mass spectrometry(GCMS) and its fumigant and repellent properties against Callosobruchus maculatus were evaluated. Sixteen ... Essential oil(EO) of Nigeria-grown Lippia adoensis leaf was analyzed using gas chromatography mass spectrometry(GCMS) and its fumigant and repellent properties against Callosobruchus maculatus were evaluated. Sixteen compounds predominated by monoterpenes were identified. The major compounds were Eucalyptol(28.36%), α-Terpineol(25.99%), γ-Terpinene(15.24%), α-Pinene(5.08%), 1H-Cyclopropa[a]naphthalene(4.25%) and 1, 3, 6, 10-Dodecatetraene(3.74%). Percentage mortality due to fumigant toxicity was dose- and exposure period-dependent. One hour after treatment(HAT), application of L. adoensis leaf EO at 107 μL· L^(-1) air caused significantly(p?0.05) higher mortality(50.00%) than 0.00% mortality observed at 0-53 μL· L^(-1) air, but not significantly(p?0.05) different from 22.50% observed in 80 μL· L^(-1) air. At 3 HAT, application of L. adoensis EO at 80 μL· L^(-1)air caused significantly higher mortality(90.00 %) than mortality observed at 0 μL· L^(-1) air. At 6 HAT, application of L. adoensis EO at 53-107 μL· L^(-1) air caused significantly higher mortality(100.00 %) than that was observed in the control. The same trend was observed at 12 HAT where 100 % mortality observed in 27-107 μL· L^(-1) air was significantly greater than 13.33 % observed in the control. At 3 HAT, percentage repellence was significantly(p<0.05) affected by doses. Application of EO at 10-30 μL· cm^(-2) caused class V repellence(86.67%-100%) compared with the control which caused class I repellence(0-20%). 展开更多
关键词 Lippia adoensis Callosobruchus maculatus GCMS bioactivity repellence FUMIGANT
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Viscoelastic Properties and Bioactivity of Sol-Gel Derived Gelatin-Silicate Composites: Effects of the Incorporated Ca^(2+) Ions
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作者 L.Ren, K.Tsuru, S.Hayakawa and A.Osaka Biomaterial Laboratory, Faculty of Engineering, Okayama University, Tsushima 3-1-1, Okayama-shi 700-8530, Japan E-mail: osaka@cc.okayama-u.ac.jp 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第3期367-370,共4页
Several gelatin-silicate composites, with or without incorporation of Ca2+ ions, were synthesized through sol-gel processing starting from gelatin and 3- (glycidoxypropyl) trimethoxysilane. The structure around the Si... Several gelatin-silicate composites, with or without incorporation of Ca2+ ions, were synthesized through sol-gel processing starting from gelatin and 3- (glycidoxypropyl) trimethoxysilane. The structure around the Si atoms was similar for all the samples. The measurement of viscoelastic properties indicated that the glass transition temperature and activation energy decreased with the incorporation of Ca2+ ions. The Ca2+ ion-containing composites were bioactive as they spontaneously deposited apatite when soaked in a simulated body fluid of the Kokubo recipe. 展开更多
关键词 Si IONS Viscoelastic Properties and bioactivity of Sol-Gel Derived Gelatin-Silicate Composites Effects of the Incorporated Ca
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Mulberry Diels-Alder-type adducts:isolation,structure,bioactivity,and synthesis
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作者 Si-Yuan Luo Jun-Yu Zhu +2 位作者 Ming-Feng Zou Sheng Yin Gui-Hua Tang 《Natural Products and Bioprospecting》 2022年第1期442-504,共63页
Mulberry Diels-Alder-type adducts(MDAAs)are unique phenolic natural products biosynthetically derived from the intermolecular[4+2]-cycloaddition of dienophiles(mainly chalcones)and dehydroprenylphenol dienes,which are... Mulberry Diels-Alder-type adducts(MDAAs)are unique phenolic natural products biosynthetically derived from the intermolecular[4+2]-cycloaddition of dienophiles(mainly chalcones)and dehydroprenylphenol dienes,which are exclusively distributed in moraceous plants.A total of 166 MDAAs with diverse skeletons have been isolated and identified since 1980.Structurally,the classic MDAAs characterized by the chalcone-skeleton dienophiles can be divided into eight groups(Types A−H),while others with non-chalcone dienophiles or some variations of classic MDAAs are non-classic MDAAs(Type I).These compounds have attracted significant attention of natural products and synthetic chemists due to their complex architectures,remarkable biological activities,and synthetic challenges.The present review provides a comprehensive summary of the structural properties,bioactivities,and syntheses of MDAAs.Cited references were collected between 1980 and 2021 from the SciFinder,Web of Science,and China National Knowledge Internet(CNKI). 展开更多
关键词 Mulberry Diels-Alder-type adducts MDAAs Natural products bioactivity SYNTHESIS
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Synthesis, Crystal Structure and Bioactivity of Ethyl 1-((2-Bromophenyl)carbamoyl)-2-(3,4,5-trimethoxyphenyl) cyclopropanecarboxylate
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作者 贾辉 钟涵宇 张敬一 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第12期2070-2076,共7页
Many small-molecule compounds were reported as microtubule-inhibitor with potential anticancer activities, such as combretastatin-A4(CA-4) analogue. The title compound which is one novel cyclopropylamide analogue of C... Many small-molecule compounds were reported as microtubule-inhibitor with potential anticancer activities, such as combretastatin-A4(CA-4) analogue. The title compound which is one novel cyclopropylamide analogue of CA-4, namely as ethyl 1-((2-bromophenyl)carbamoyl)-2-(3,4,5-trimethoxyphenyl)cyclopropanecarboxylate, has been synthesized and its crystal structure was characterized by X-ray single-crystal diffraction. The crystal belongs to monoclinic, space group P21/n with a = 8.8002(6), b = 11.4525(8), c = 21.7870(16)A, β = 93.810(3)°, V = 2190.9(3)A^3, Z = 4, C22H23BrNO6, Mr = 477.32, Dc = 1.447 Mg/cm^3, F(000) = 980, λ(Cu Kα) = 1.54178A, μ = 2.883 mm^–1, R = 0.0691 and wR = 0.1958 for 6420 observed reflections(I > 2σ(I)). Importantly, the compound revealed potential anticancer activities in six cancer cells and could stimulate tubulin polymerization in vitro, indicating that the small-molecule could be selected as a lead compound for the development of microtubule stimulator. 展开更多
关键词 cycolpropylamide analogues SYNTHESIS bioactivity microtubule-stabilizing agents
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