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Study of a water-soluble supramolecular complex of curcumin andβ-cyclodextrin polymer with electrochemical property and potential anti-cancer activity
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作者 Wang Zhang Ping Xiao +4 位作者 Liwei Lin Fang Guo Qingyue Wang Yuanzhe Piao Guowang Diao 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第8期4043-4047,共5页
As a member of the curcuminoid compound family,curcumin(Cur)has many interesting therapeutic properties.However,its low aqueous solubility and stability have resulted in poor bioavailability and restricted clinical ef... As a member of the curcuminoid compound family,curcumin(Cur)has many interesting therapeutic properties.However,its low aqueous solubility and stability have resulted in poor bioavailability and restricted clinical efficacy.Based on size matching,β-cyclodextrin polymer(β-CDP),with its hydrophilic polymer chains and hydrophobic cavities,can form an inclusion complex with Cur.To improve the water solubility and stability of Cur,a simple and eco-friendly grinding method was designed to formβ-CDP inclusion complexes.According to the Boltzmann-Hamel's method and Job's method,the molar ratio of theβ-CD unit inβ-CDP to Cur was determined to be 1:1.The diffusion coefficient and diffusion activation energy of Cur-β-CDP were calculated in an electrochemical study.This supramolecular complex worked well in vitro to inhibit the proliferation of hepatoma carcinoma cells HepG2.Remarkably,this method visibly reduced the undesirable side effects on normal cells,without weakening the anti-cancer activity of the drugs.We expect that the obtained host-vip complex will provide a new approach for delivering natural drug molecules,having low water solubility. 展开更多
关键词 Cyclodextrin polymer CURCUMIN SOLUBILITY anti-cancer activity Supramolecular complex
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Anti-cancer activity of an ethyl-acetate extract of the fruits of Terminalia bellerica(Gaertn.)Roxb.through an apoptotic signaling pathway in vitro 被引量:7
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作者 Shi Li Ting Ye +4 位作者 Linjin Liang Wenyi Liang Ping Jian Kun Zhou Lanzhen Zhang 《Journal of Traditional Chinese Medical Sciences》 2018年第4期370-379,共10页
Objective:To investigate the biochemical constituents of the fruits of Terminalia bellerica(Gaertn.)Roxb.(hereafter termed T.bellerica)and estimate the anti-cancer activity of different polar extracts.Methods:To rapid... Objective:To investigate the biochemical constituents of the fruits of Terminalia bellerica(Gaertn.)Roxb.(hereafter termed T.bellerica)and estimate the anti-cancer activity of different polar extracts.Methods:To rapidly screen and identify the biochemical constituents of ethyl acetate(EA)extracts of T.bellerica,ultra performance liquid chromatography-electrospray ionization/mass spectrometry(UPLC-ESI-MSn)was done.The CellTiter-BlueTM cell-viability assay was used to ascertain the anti-cancer activity of different polar extracts in 10 human cancer cell lines.Results:Forty polyphenols of the EA extract of T.bellerica were characterized tentatively.The EA extract exhibited significant anti-cancer activity against ZR-75-1 cells(half-maximal inhibitory concentration=27.33(0.98)μg/mL)and Colo-205 cells(39.65(2.99)μg/mL)in vitro.Treatment of ZR-75-1 cells with 20 and 60μg/mL of the EA extract elicited dosedependent apoptosis percentages at an early stage of 17.58(0.74)%and at a late stage of 29.20(1.22)%;Colo-205 cells at the same concentration of EA extract had values of 21.33(1.03)%and 40.55(0.34)%,respectively.Western blotting suggested that ZR-75-1 and Colo205 cells treated with the EA extract showed a similar increasing tendency for expression of cleaved anti-poly adenosine diphosphate ribose polymerase I.Conclusion:We identified a total of 40 chemical constituents,of which 11 were first obtained from the Terminalia Linn.genus using UPLC-ESI-MSn.Meanwhile,we observe that the EA extract of T.bellerica possesses anti-cancer activity,especially against breast and colon cancers. 展开更多
关键词 TERMINALIA bellerica anti-cancer activity UPLC-ESI-MSn CellTiter-blue
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Potential Anti-cancer Activity of Furanodiene 被引量:7
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作者 Zhen-zhen Ba Yan-ping Zheng Hui Zhang Xiu-yan Sun Dong-hai Lin 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2009年第2期154-158,共5页
Objective: To study the isolated from the essential oil VIVO anti-tumor activities of furanodiene of the rhizome of Curcuma wenyujin (C15H200), a primary sesquiterpene compound YH Chen et C. Ling(Wen Ezhu), in vi... Objective: To study the isolated from the essential oil VIVO anti-tumor activities of furanodiene of the rhizome of Curcuma wenyujin (C15H200), a primary sesquiterpene compound YH Chen et C. Ling(Wen Ezhu), in vitro and in Methods: In vitro MTT assay was used to further study the effects of time and dosage on anti-proliferation of furanodiene against the sensitive Hela, Hep-2, HL-60, U251 cells, based on the cytotoxic effects of furanodiene on 12 human malignant tumor cell lines with the essential oil of Wen Ezhn as control., and the half-inhibitory concentration (IC50) was observed. In vivo uterine cervix (U14) tumor cell was selected and the conventional assay method of anti-tumor activity was employed. Furanodiene liposome was administered intraperitoneally, and tumor-inhibitory rate, thymus and spleen indexes were observed. Results: The inhibitive effects on cell proliferation were shown in all of the twelve cell lines and the cytotoxic effects of furanodiene against Hela, Hep-2, HL-60, U251 cells were observed after 12 h of administration, the effect could last for at least 48 h in a dose dependent manner, and the IC50 values were 0.6, 1.7, 1.8, 7.0μg/ml, respectively. Furanodiene was also found to show inhibitive effects on the proliferation of uterine cervix (U14) tumor induced in mice. The tumor inhibition rates were 36.09% (40 mg/kg), 41.55% (60 mg/kg), 58.29% (80 mg/kg), respectively. Conclusion: Furanodiene is one of primary anti-cancer active components in the essential oil of Wen Ezhu, and also a very effective agent against uterine cervix cancer, and has protection effect on the immune function. 展开更多
关键词 Essential oil of Wen Ezhu FURANODIENE anti-cancer Uterine cervix cancer
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Quantitative Structure Anti-Cancer Activity Relationship (QSAR) of a Series of Ruthenium Complex Azopyridine by the Density Functional Theory (DFT) Method 被引量:5
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作者 Kouakou Nobel N’guessan Mamadou Guy-Richard Koné +2 位作者 Kafoumba Bamba Ouattara Wawohinlin Patrice Nahossé Ziao 《Computational Molecular Bioscience》 2017年第2期19-31,共13页
A series of ruthenium azopyridine complexes have recently been investigated due to their potential cytotoxic activities against renal cancer (A498), lung cancer (H226), ovarian cancer (IGROV), breast cancer (MCF-7) an... A series of ruthenium azopyridine complexes have recently been investigated due to their potential cytotoxic activities against renal cancer (A498), lung cancer (H226), ovarian cancer (IGROV), breast cancer (MCF-7) and colon cancer (WIDR). Thus, in order to predict the cytotoxic potentials of these compounds, quantitative structure-activity relationship studies were carried out using the methods of quantum chemistry. Five Quantitative Structure Activity Relationship (QSAR) models were obtained from the determined quantum descriptors and the different activities. The models present the following statistical indicators: regression correlation coefficient R2 = 0.986 - 0.905, standard deviation S = 0.516 - 0.153, Fischer test F = 106.718 - 14.220, correlation coefficient of cross-validation = 0.985- 0.895 and = 0.010 - 0.001. The statistical characteristics of the established QSAR models satisfy the acceptance and external validation criteria, thereby accrediting their good performance. The models developed show that the variation of the free enthalpy of reaction , the dipole moment μ and the charge of the ligand in the complex Ql, are the explanatory and predictive quantum descriptors correlated with the values of the anti-cancer activity of the studied complexes. Moreover, the charge of the ligand is the priority descriptor for the prediction of the cytotoxicity of the compounds studied. Furthermore, QSAR models developed are statistically significant and predictive, and could be used for the design and synthesis of new anti-cancer molecules. 展开更多
关键词 RUTHENIUM Azopyridine Complex anti-cancer QSAR DFT METHOD
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Study on the Synthesis and in vitro Photodynamic Anti-cancer Activity of Tetra(trifluoroethoxy) Germanium Phthalocyanine 被引量:3
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作者 吴丽荣 黄丽英 林振华 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第7期1081-1090,共10页
The synthesis and in vitro photodynamic anticancer activity of a new photosen- sitizer, tetra(trifluoroethoxy) germanium phthalocyanine (GePcF), were studied. GePcF was characterized by UV-Vis, IR, MS and elementa... The synthesis and in vitro photodynamic anticancer activity of a new photosen- sitizer, tetra(trifluoroethoxy) germanium phthalocyanine (GePcF), were studied. GePcF was characterized by UV-Vis, IR, MS and elemental analysis. The in vitro photodynamic activity of GePcF was studied by MTT. IC50 of GePcF for SW480 cells of human colonic adenocarcinoma and HeLa cells of cervical cancer were 36.53 and 45.78 μmol/L, respectively. GePcF as a photosensitizer may be used to treat cancers due to its photodyrmmic anticancer activity. 展开更多
关键词 tetra(trifluoroethoxy) germanium phthalocyanine synthesis characterization photodynamic activity
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Sesamum indicum(sesame) enhances NK anti-cancer activity, modulates Th1/Th2 balance, and suppresses macrophage inflammatory response 被引量:1
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作者 Amin FMajdalawieh Jenna F.Farraj Ronald I.Carr 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2020年第7期316-324,共9页
Objective:To evaluate the potential immunomodulatory effects of an aqueous extract of Sesamum indicum seeds with regard to splenocyte proliferation,Th1/Th2 balance,macrophage function,and the cytotoxic activity of nat... Objective:To evaluate the potential immunomodulatory effects of an aqueous extract of Sesamum indicum seeds with regard to splenocyte proliferation,Th1/Th2 balance,macrophage function,and the cytotoxic activity of natural killer(NK)cells.Methods:Splenocyte proliferation was measured by[~3H]-thymidine incorporation.Griess assay was performed to evaluate the production of nitric oxide by macrophages.The levels of cytokines secreted by splenocytes and macrophages were measured by ELISA.JAM assay was performed to examine the cytotoxic activity of NK cells against YAC-1 tumor cells.Results:Sesamum indicum significantly enhanced splenocyte proliferation in a dose-dependent manner.Sesamum indicum also increased and suppressed the secretion of Th1 and Th2 cytokines,respectively,by splenocytes.The secretion of key pro-inflammatory mediators(IL-6,TNFα,and nitric oxide)by primary macrophages was significantly inhibited by Sesamum indicum.Moreover,Sesamum indicum increased the cytotoxic activity of NK cells against YAC-1 tumor cells.Conclusions:Sesamum indicum shows potent immunomodulatory,anti-inflammatory,and anti-cancer effects.Constituents of Sesamum indicum may be used as effective therapeutic agents in regulating immune reactions implicated in various infectious and noninfectious conditions including cancer. 展开更多
关键词 Sesamum indicum anti-cancer Inflammation IMMUNOMODULATION MACROPHAGES NK cells
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DT-13, a saponin of dwarf lilyturf tuber, exhibits anti-cancer activity by down-regulating C-C chemokine receptor type 5 and vascular endothelial growth factor in MDA-MB-435 cells 被引量:7
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作者 ZHAO Ren-Ping LIN Sen-Sen +4 位作者 YUAN Sheng-Tao YU Bo-Yang BAI Xian-Shu SUN Li ZHANG Lu-Yong 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2014年第1期24-29,共6页
AIM: To investigate the anticancer activity of DT-13 under normoxia and determine the underlying mechanisms of action. METHODS: MDA-MB-435 cell proliferation, migration, and adhesion were performed to assess the ant... AIM: To investigate the anticancer activity of DT-13 under normoxia and determine the underlying mechanisms of action. METHODS: MDA-MB-435 cell proliferation, migration, and adhesion were performed to assess the anticancer activity of DT-13, a saponin from Ophiopogonjaponicus, in vitro. In addition, the effects of DT-13 on tumor growth and metastasis in vivo were evaluated by orthotopic implantation of MDA-MB-435 cells into nude mice; mRNA levels of vascular endothelial growth factor (VEGF), C-C chemokine receptor type 5 (CCR5) and hypoxia-inducible factor 1a (HIF-1a) were evaluated by real-time quantitative PCR; and CCR5 protein levels were detected by Western blot assay. RESULTS: At 0.01 to 1 umol·L -1, DT-13 inhibited MDA-MB-435 cell proliferation, migration, and adhesion significantly in vitro. DT-13 reduced VEGF and CCR5 mRNAs, and decreased CCR5 protein expression by down-regulating HIF-1 a. In addition, DT-13 inhibited MDA-MB-435 cell lung metastasis, and restricted tumor growth slightly in vivo. CONCLUSION: DT-13 inhibited MDA-MB-435 cell proliferation, adhesion, and migration in vitro, and lung metastasis in vivo by reducing VEGF, CCR5, and HIF-la expression. 展开更多
关键词 DT- 13 SAPONIN Ophiopogonjaponicus Anticancer activity CCR5 VEGF HIF- 1 a
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Short-chain fructooligosaccharides synthesis using a commercial enzyme complex from Aspergillus sp.and anti-cancer activity on HCT116 and HT-29 cell lines
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作者 Meda Bytautaite Vaida Kitryte-Syrpa +3 位作者 Paulina Jonute Ugne Endriulaityte Vilma Petrikaite Michail Syrpas 《Food Bioscience》 2024年第5期5500-5510,共11页
Over the last years,short-chain fructooligosaccharides(FOS)have gained significant attention as valuable food and dietary supplement components.Apart from implications such as dietary fibres,sweeteners,and humectants,... Over the last years,short-chain fructooligosaccharides(FOS)have gained significant attention as valuable food and dietary supplement components.Apart from implications such as dietary fibres,sweeteners,and humectants,FOS are hailed for their prebiotic properties.Moreover,much research is dedicated to their role as anti-cancer agents.Despite the ongoing interest,both technical aspects,challenges of FOS production,and their anti-cancer role necessitate more in-depth in-vestigations to understand their healthcare role better.This study aimed to optimise critical FOS synthesis parameters using a commercial enzyme,Viscozyme®L,to obtain a preparation with a high FOS content.A central composite design and response surface methodology evaluated the effect of pH,temperature,synthesis time,substrate,and enzyme load on multiple responses,chosen as independent variables,were utilised to define optimal conditions.Under the optimal conditions(temperature 50℃,pH 5.5,sucrose concentration 352 g/L,enzyme concentration 2.5%v/v,and 5.5 h of reaction),a preparation with a total FOS content of 58.8%was obtained.The FOS preparation showed minimal in vitro antioxidant capacity in the ORAC,CUPRAC,and ABTS^(*+)assays.In addition,the cytotoxicity of FOS against tested cell lines was evaluated.FOS did not reduce HT-29 cell viability even at the concentration of 2.5 mg/mL,whereas FOS inhibited the proliferation of HCT116 cells by 50%at 2.35 mg/mL.Finally,the sensitisation effect of FOS on HCT116 cell treatment with doxorubicin has been revealed. 展开更多
关键词 HT food dietary supplement Aspergillus sp HCT synthesis short chain fructooligosaccharides anti cancer activity dietary fibressweetenersand
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Prenylated flavonoids from Glycyrrhiza uralensis as promising anti-cancer agents: a preliminary structure-activity study 被引量:8
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作者 唐叔南 黄维 +4 位作者 季帅 王永瑞 裴道勇 叶敏 余四旺 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2016年第1期23-29,共7页
Prenylated flavonoids are mainly distributed in Leguminosae and Moraceae plants, and they have been reported to possess various biological activities. Previously, we have reported a prenylated isoflavonoid, isoangusto... Prenylated flavonoids are mainly distributed in Leguminosae and Moraceae plants, and they have been reported to possess various biological activities. Previously, we have reported a prenylated isoflavonoid, isoangustone A(IAA) from licorice(Glycyrrhiza uralensis), which induces apoptosis in colorectal cancer cells by disrupting mitochondrial functions. In the present study, we compared a group of flavonoids from licorice with IAA for their anti-proliferation activities and effects on intracellular signaling. The results indicated that the isoprenyl groups on the A and B rings, the hydroxyl groups at the ortho position of isoprenyl on A ring and the conjugated plane of C ring might contribute to the anti-cancer activity of prenylated flavonoids. Based on the above structure-activity relationship, we further identified four prenylated flavonoids with similar anti-cancer activities from licorice. Taken together, our present study established a preliminary structure-activity relationship of anti-cancer prenylated flavonoids, and our data provided important leading compounds from licorice, which deserved further research and development. 展开更多
关键词 Prenylated flavonoids LICORICE anti-cancer Structure-activity relationship
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Two New Linear Furocoumarins from Notopterygium incisum and Their Anti-inflammatory Activity
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作者 Hu Su Zhao Lilian +4 位作者 Li Xinyu Ye Yubei Deng Yun Huang Lijun Guo Dale 《有机化学》 北大核心 2026年第1期300-303,共4页
Two new linear furocoumarins were isolated from Notopterygium incisum using silica gel,gel Sephadex LH-20 column chromatography,and preparative high-performance liquid chromatography.The structures of the new compound... Two new linear furocoumarins were isolated from Notopterygium incisum using silica gel,gel Sephadex LH-20 column chromatography,and preparative high-performance liquid chromatography.The structures of the new compounds were elucidated through analysis of spectroscopic evidence,including data obtained from high-resolution electrospray ionization mass spectrometry(HRESIMS)and nuclear magnetic resonance(NMR).The absolute configurations of Notoprenylate L(1)and Nototerprinol K(2)were further confirmed using electronic circular dichroism(ECD)calculations.Compound 1 demonstrated the ability to inhibit the expression of nitric oxide(NO),a pro-inflammatory factor,in lipopolysaccharide-induced RAW264.7 macrophages at a concentration of 7.5μmol/L,indicating its potential for anti-inflammatory activity. 展开更多
关键词 Notopterygium incisum linear furocoumarin anti-inflammatory activity
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Synthesis,structural characterization,electrocatalytic proton reduction,and fungicidal activity of thiazole‑containing di‑iron complexes
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作者 JIANG Chengyu LIU Xufeng 《无机化学学报》 北大核心 2026年第2期355-364,共10页
This paper reports the preparation of three di‑iron complexes containing a thiazole moiety.Esterification of complex[Fe_(2)(CO)_(6)(μ‑SCH_(2)CH(CH_(2)OH)S)](1)with 4‑methylthiazole‑5‑carboxylic acid gave the correspo... This paper reports the preparation of three di‑iron complexes containing a thiazole moiety.Esterification of complex[Fe_(2)(CO)_(6)(μ‑SCH_(2)CH(CH_(2)OH)S)](1)with 4‑methylthiazole‑5‑carboxylic acid gave the corresponding ester[Fe_(2)(CO)_(6)(μ‑tedt)](2),where tedt=SCH_(2)CH(CH_(2)OOC(5‑C_(3)HNSCH_(3)))S.Further reactions of complex 2 with tri(ptolyl)phosphine(tp)or tris(4‑fluorophenyl)phosphine(fp)gave the phosphine‑substituted derivatives[Fe_(2)(CO)_(5)(tp)(μ‑tedt)](3)and[Fe_(2)(CO)_(5)(fp)(μ‑tedt)](4).The structures of the newly prepared complexes were elucidated by elemental analysis,NMR,IR,and X‑ray photoelectron spectroscopy.Moreover,single‑crystal X‑ray diffraction analysis confirmed their molecular structures,showing that they contain a di‑iron core ligated by a bridged dithiolate bearing a thiazole moiety and terminal carbonyls.The electrochemical and electrocatalytic proton reduction were probed by cyclic voltammetry,revealing that three complexes can catalyze the reduction of protons to H_(2) under the electrochemical conditions.For comparison,complex 4 possessed the best efficiency with a turnover frequency of 23.5 s^(-1)at 10 mmol·L^(-1)HOAc concentration.In addition,the fungicidal activity of these complexes was also investigated in this study.CCDC:2477511,2;2477512,3;2477513,4. 展开更多
关键词 THIAZOLE di‑iron complex crystal structure electrocatalytic proton reduction fungicidal activity
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Navigating physical activity research in complex terrains:Reflections on the challenges,opportunities,and future directions
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作者 Ding Ding 《Journal of Sport and Health Science》 2026年第3期3-5,共3页
In 2025,I had the honor of delivering keynote speeches at the conferences of the International Society for Diet and Activity Methods in Toronto,Canada,and the International Society of Behavioural Nutrition and Physica... In 2025,I had the honor of delivering keynote speeches at the conferences of the International Society for Diet and Activity Methods in Toronto,Canada,and the International Society of Behavioural Nutrition and Physical Activity in Auckland,Aotearoa,New Zealand.These opportunities prompted deep reflection on scientific research in general,and on physical activity and health research specifically. 展开更多
关键词 scientific research complex terrains future directions diet activity methods research challenges physical activity behavioural nutrition physical activity
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Silver chloride/chitosan‑based chloramine nanohybrid with excellent antibacterial activity:Design and structure characterization as well as Ag^(+)‑Cl^(-)synergistic antibacterial effect
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作者 ZHANG Xinzhe XU Jiarong +4 位作者 GAO Mochou LIU Yage ZHAO Yanbao CUI Jingzeng ZOU Xueyan 《无机化学学报》 北大核心 2026年第2期428-438,共11页
Chitosan(CTS)was grafted onto the surface of amino‑functionalized silver chloride silicon dioxide(AgCl@SiO_(2)‑NH_(2))cores to obtain AgCl@SiO_(2)/CTS hybrid nanoparticles.The as‑obtained AgCl@SiO_(2)/CTS nanoparticle... Chitosan(CTS)was grafted onto the surface of amino‑functionalized silver chloride silicon dioxide(AgCl@SiO_(2)‑NH_(2))cores to obtain AgCl@SiO_(2)/CTS hybrid nanoparticles.The as‑obtained AgCl@SiO_(2)/CTS nanoparticles were chlorinated by NaClO solution to get AgCl@SiO_(2)/CTS‑based chloramine nano‑hybrid materials,denoted as AgCl@SiO_(2)/CTS‑Cl.A transmission electron microscope was used to observe the morphology of the as‑prepared samples AgCl@SiO_(2)/CTS and AgCl@SiO_(2)/CTS‑Cl.At the same time,an X‑ray diffractometer and an infrared spectroscope were utilized to characterize their crystal and chemical structures.Besides,ζpotentials were measured to elucidate the surface modification of AgCl nanoparticles by—NH_(2),the antibacterial mechanism of AgCl@SiO_(2)/CTS‑Cl was investigated by scanning electron microscopy,and Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)were used as the to‑be‑tested strains to evaluate the antimicrobial activity of samples AgCl@SiO_(2)/CTS and AgCl@SiO_(2)/CTS‑Cl.Findings demonstrate that sample AgCl@SiO_(2)/CTS exhibits a chain‑like structure ascribed to the interaction between—NH_(2),and each AgCl@SiO_(2)/CTS hybrid nanoparticle contains several AgCl cores.In the meantime,sample AgCl@SiO_(2)/CTS‑Cl exhibits excellent antibacterial activity against E.coli and S.aureus,which is attributed to the synergistic antibacterial effect of Ag^(+)and Cl^(-).Sample AgCl@SiO_(2)/CTS‑Cl with a dosage of 640.00μg·mL^(-1) could completely kill the two kinds of tested bacteria in 12 h of incubation;it retains a high antibacterial efficiency even after 10 cycles of antibacterial tests. 展开更多
关键词 AgCl@SiO_(2)/CTS‑Cl hybrid nanoparticle synergistic effect antibacterial activity
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The activity characteristics and mechanisms of long-period comets
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作者 YingQi Wu JianChun Shi +1 位作者 Man-To Hui Xian Shi 《Earth and Planetary Physics》 2026年第2期374-384,共11页
Comets are small celestial bodies orbiting around the Sun.They are remnants left over from the formation of the solar system;their interiors store original material of the planetary disk within the solar system.They a... Comets are small celestial bodies orbiting around the Sun.They are remnants left over from the formation of the solar system;their interiors store original material of the planetary disk within the solar system.They are thus"fossils"for studying the early solar system.According to their orbital periods,comets are classified as long-period comets(orbital period P>200 years)and short-period comets(P<200 years).Long-period comets originate from the Oort Cloud.Compared to short-period comets,they enter the inner solar system less frequently and contain more primitive materials.Studying long-period comets helps us understand the origin of the solar system and reveals characteristics of the Oort Cloud.This paper begins with a summary of our extensive survey of the literature regarding methods of observing comets and foci of comet studies.We introduce systematically the main parameters currently used to assess the activity of long-period comets,including gas production rate,dust production rate,dust properties,morphological characteristics,etc.Subsequently,we discuss in depth the activity mechanisms of long-period comets,covering not only the water ice sublimation-driven mechanism(similar to that of short-period comets)but also various mechanisms that may dominate the activity of long-period comets in the low-temperature environment at the aphelion.These mechanisms include the sublimation of CO or CO_(2) gas ice,the polymerization reaction of cyanides,the crystallization of amorphous water ice,the annealing process of amorphous water ice,the thermal decomposition effect,and the electrostatic supercharge phenomenon.We then summarize the evolving activity of long-period comets as they travel from the Oort Cloud to the vicinity of their perihelions.We analyze unique properties of long-period comets,including such special phenomena as changes in dust color,coma structure,and tail structure.Finally,we summarize currently unresolved scientific questions,and then the entire paper. 展开更多
关键词 comets long-period comets activity
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Preoperative butyrylcholinesterase activity and risk of postoperative delirium:A meta-analysis
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作者 Yuan-Li Qiu Cheng Song +1 位作者 Cui-Wan Huang Wei-Gang Shen 《World Journal of Psychiatry》 2026年第1期385-399,共15页
BACKGROUND Postoperative delirium(POD)is a common and serious complication in surgical patients,particularly older adults.Alterations in cholinergic function have been implicated in its pathophysiology.AIM To evaluate... BACKGROUND Postoperative delirium(POD)is a common and serious complication in surgical patients,particularly older adults.Alterations in cholinergic function have been implicated in its pathophysiology.AIM To evaluate the association between preoperative serum cholinesterase(ChE)activity—specifically butyrylcholinesterase(BuChE)and acetylcholinesterase(AChE)—and the risk of POD in adult surgical patients in a meta-analysis.METHODS A systematic search was conducted in PubMed,EMBASE,and Web of Science up to March 28,2025 for studies reporting preoperative serum BuChE or AChE activity in relation to subsequent POD incidence.Standardized mean differences(SMDs)and odds ratios(ORs)with 95%confidence intervals(CIs)were pooled using random-effects models.Subgroup and sensitivity analyses were performed based on follow-up duration and analytic models.RESULTS Thirteen studies(n=2730 patients)were included.Patients who developed POD had significantly lower preoperative BuChE activity than those who did not(SMD=-0.28;95%CI:-0.39 to-0.16;I^(2)=18%).Higher BuChE activity was associated with a reduced risk of POD(OR per 100 unit increment=0.97;95%CI:0.95-0.99;I2=0%).In contrast,pooled AChE activity did not differ significantly between POD and non-POD groups(SMD=-0.25;95%CI:-0.53 to 0.03;P=0.08;I^(2)=80%),and the ORs per 1 unit increment in AChE activity were not statistically significant(OR=0.98;95%CI:0.95-1.01).CONCLUSION Lower preoperative serum BuChE activity is associated with an increased risk of POD in adults undergoing surgery.BuChE activity may serve as a potential preoperative biomarker for POD risk stratification. 展开更多
关键词 ACETYLCHOLINESTERASE BUTYRYLCHOLINESTERASE activity Postoperative delirium META-ANALYSIS
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Activity-dependent regulation of cortical cell numbers:Role of neuronal activity in cortical circuit formation
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作者 Fong Kuan Wong 《Neural Regeneration Research》 2026年第8期3521-3522,共2页
The mammalian cerebral cortex,despite its variation in brain shape and size,is a stereotypical six-layered structure composed of pyramidal cells,interneurons,astrocytes,microglia,oligodendrocytes,and endothelial cells... The mammalian cerebral cortex,despite its variation in brain shape and size,is a stereotypical six-layered structure composed of pyramidal cells,interneurons,astrocytes,microglia,oligodendrocytes,and endothelial cells.During development,these cells differ in their origin,birth timing,and developmental trajectories.Nonetheless,they converge during development,forming nascent cortical circuits crucial for organismal behavior.While the relative proportions of cortical cells vary between regions. 展开更多
关键词 neuronal activity mammalian cerebral cortex pyramidal cellsinterneuronsastrocytesmicrogliaoligodendrocytesand cortical cell numbers nascent cortical circuits endothelial cellsduring activity dependent cortical cells
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Study on the Extraction of Flavonoids from Hylocereus undatus(Haw.)Britton&Rose and Their Antioxidant Activity
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作者 Zhao LIU Deyun MA +1 位作者 Rimeng CHEN Meijiao MO 《Agricultural Biotechnology》 2026年第1期65-69,共5页
[Objectives]This study was conducted to investigate the extraction process,content determination,and antioxidant properties of flavonoids from Hylocereus undatus(Haw.)Britton&Rose.[Methods]Using H.undatus as the r... [Objectives]This study was conducted to investigate the extraction process,content determination,and antioxidant properties of flavonoids from Hylocereus undatus(Haw.)Britton&Rose.[Methods]Using H.undatus as the raw material,the effects of ethanol concentration,ultrasonic temperature,time,and solid-to-liquid ratio on the total flavonoid yield were investigated through single-factor and orthogonal experiments.[Results]All factors had a significant effect on the yield.The optimized conditions were determined as follows:ethanol concentration 75%,ultrasonic temperature 60℃,ultrasonic time 30 min,and solid-to-liquid ratio 1:50(g/ml).Under these conditions,the total flavonoid yield reached 3.08%.Evaluation of antioxidant activity revealed that the extract exhibited superior scavenging rates against both DPPH and hydroxyl radicals compared with the standard reference compound BHT.[Conclusions]This study holds significant importance for elucidating the pharmacological mechanisms of flavonoids in H.undatus and for expanding their application in medicine and health products. 展开更多
关键词 Hylocereus undatus FLAVONOIDS Antioxidant activity
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Conductive materials change the composition and activity of butyrate-degrading enrichment cultures with hydrogen as the main electron shuttle
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作者 Cátia S.N Braga João C.Sequeira +5 位作者 M.SaloméDuarte Gilberto Martins Inês A.C.Pereira c Luciana Pereira M.Madalena Alves Andreia F.Salvador 《Journal of Environmental Sciences》 2026年第1期624-634,共11页
Conductive materials(CM)can improve methane production(MP)efficiency in many methanogenic systems.However,several types of CM exist,and there are uncertainties regarding whether they all improve MP efficiency to the s... Conductive materials(CM)can improve methane production(MP)efficiency in many methanogenic systems.However,several types of CM exist,and there are uncertainties regarding whether they all improve MP efficiency to the same extent and modulate microbial communities in a similar way.To investigate that,different microbial enrichments with and without activated carbon(AC),magnetite(Mag),and zeolites(Zeo)(at 0.5 g/L)were developed.MP profiles and microbial composition changes were compared among enrichments.The behavior of all enrichments was different,although the initial inoculum sludge was the same.Lag phase duration was lower in AC enrichment,while the complete conversion of butyrate to methane was faster in Mag enrichment.Syntrophomonas was the most abundant bacterial genus in all enrichments,but changes in the methanogenic community were evident.Acetoclastic methanogens were more diverse in Mag enrichment,with microorganisms assigned to Methanosarcina and Methanothrix gener1,but Methanothrix was the only acetoclastic methanogen in the other enrichments.On the other hand,different species of hydrogenotrophic methanogens prevailed in distinct enrichments.The metatranscriptomics results revealed that the dominant mechanism of interspecies electron transfer in the AC enrichment utilized hydrogen as the electron carrier,and no evidences of direct interspecies electron transfer(DIET)could be found.These results showed how different CM modulate microbial communities and affect MP efficiency through mechanisms that do not necessarily involve DIET or mediation via CM. 展开更多
关键词 BUTYRATE METHANE Anaerobic enrichments activated carbon MAGNETITE Zeolites
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Synthesis and insecticidal activity evaluation of sulfonamide derivatives oriented by atom replacement strategy
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作者 Hao Qian Xinru Tan +8 位作者 Guixun Wu Lei Wang Ziyu Wang Hongxiang Liu Mei Tian Minjie Zhang Keyin Yu Wenjun Wu Jiwen Zhang 《Advanced Agrochem》 2026年第1期49-57,共9页
The single-atom replacement strategy is a typical approach which just converts elements in lead compounds into their analogues with very small chemical changes.In this research,we implemented this strategy to modify t... The single-atom replacement strategy is a typical approach which just converts elements in lead compounds into their analogues with very small chemical changes.In this research,we implemented this strategy to modify the sulfonamide scaffold identified in our previous work,and resulting in the synthesis of 40 novel sulfonamide derivatives not previously reported in the literature.The insecticidal activities of these compounds against the Mythimna separata and Plutella xylostella were assessed.Our findings indicate that the pyridine sulfonamide structure significantly enhances insecticidal efficacy.Specifically,compound 7c exhibited LC 50 values of 0.157 and 0.256 mg/mL against the M.separata and P.xylostella,which significantly increased 97-and 41-fold compared to celangulin V,respectively.The experimental results revealed that pyridine sulfonamide analogues could serve as potential green insecticides. 展开更多
关键词 SULFONAMIDE SYNTHESIS Insecticidal activity Atom replacement Celangulin V
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Associations of accelerometer-measured light-intensity physical activity with mortality and incidence of cardiovascular diseases and cancers:A prospective cohort study
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作者 Jiahong Sun Yanan Qiao +5 位作者 Fei Li Ruilang Lin Yongfu Yu Mingming Wang Min Zhao Bo Xi 《Journal of Sport and Health Science》 2026年第3期61-73,共13页
Background:Although light-intensity physical activity(LPA)has been suggested to be associated with a lower risk of mortality,the minimal and optimal volumes of LPA remain unclear.We aimed to examine the minimal and op... Background:Although light-intensity physical activity(LPA)has been suggested to be associated with a lower risk of mortality,the minimal and optimal volumes of LPA remain unclear.We aimed to examine the minimal and optimal volumes of LPA associated with the risks of mortality and disease incidence(i.e.,cardiovascular diseases and cancer).Methods:Data were derived from the population-based UK Biobank cohort study,including 69,492 adults aged 43-78 years.Accelerometermeasured LPA was defined using a validated,published machine learning-based Random Forest activity method,which was categorized into 4 quartile groups.All-cause and cause-specific mortality(cardiovascular disease-and cancer-specific)were determined according to the International Classification of Diseases,10th version codes.Disease incidence was defined based on primary care,hospitalization,or death records.Results:During a median follow-up period of 8.04 years,2024 adults died from all causes,539 from cardiovascular disease,and 1175 from cancer.For all-cause mortality,compared with participants in the lowest quartile of LPA(<3.9 h/day),the hazard ratios(HRs)and 95%confidence intervals(95%CIs)were 0.82(95%CI:0.73-0.93)for those with 3.9 to<5.0 h/day,0.75(95%CI:0.66-0.85)for those with 5.0 to<6.1 h/day,and 0.77(95%CI:0.68-0.88)for those with≥6.1 h/day,respectively.There was an inverse non-linear dose-response association between LPA and all-cause mortality,with an optimal dose of 5.72 h/day(95%CI:5.45-6.41;HR=0.63,95%CI:0.56-0.71)and a minimal dose of 3.59 h/day(95%CI:3.53-8.56;HR=0.81,95%CI:0.78-0.86),with the 5th percentile as the reference.Similar patterns were observed for cause-specific mortality and disease incidence(cardiovascular disease and cancer).Conclusion:Engaging in LPA for~3.5 h/day was conservatively associated with lower risk of mortality and disease incidence,with further risk reductions observed up to an optimal dose of~6.0 h/day.These findings suggest that sufficient LPA offers important health benefits,which can inform the development of future PA guidelines. 展开更多
关键词 Light-intensity physical activity MORTALITY Cardiovascular disease Cancer
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