为系统了解国内外生物固氮的研究现状,本研究基于在Web of Science(WOS)核心合集数据库及中国知网(CNKI)检索的1990—2023年有关生物固氮研究的文献,利用Citespace、VOSviewer、HistCite等文献计量工具,对发文数量、主要国家(地区)与机...为系统了解国内外生物固氮的研究现状,本研究基于在Web of Science(WOS)核心合集数据库及中国知网(CNKI)检索的1990—2023年有关生物固氮研究的文献,利用Citespace、VOSviewer、HistCite等文献计量工具,对发文数量、主要国家(地区)与机构、主要发文期刊和研究学者、重要文献、研究热点以及研究变化趋势等进行了计量分析。结果表明,1)近24年来,生物固氮研究领域发文量呈逐年增多趋势,2010年后中国发文占比显著增多,并成为WOS数据库中生物固氮领域发文量排名第2的国家,且与美国、巴西、德国等发文量较多的国家之间联系密切。植物科学、微生物学是英文发文量较多的学科,生物学、作物学是中文发文量较多的学科,都与农业科学紧密相关。生物固氮相关研究的中英文论文主要发文期刊是《生物技术通报》、《Plant and Soil》、《Soil Biology&Biochemistry》。Hungria M、Urquiaga S、Boddey R M和李友国是该领域发文较多的研究学者。2)生物固氮关键词聚类网络主要可分为生物固氮相关微生物及其定殖,生物固氮对农业生产的影响,生物固氮分子机理,以及生物固氮影响因素等4类,如何提升生物固氮效率并扩大其应用范围成为研究者关注的焦点。3)生物固氮研究近些年的主要挑战包括:扩大根瘤菌宿主范围,提高根际联合固氮效率;将生物固氮引入禾谷类作物中,开发“氮肥自供型”作物;挖掘高效固氮微生物资源,优化菌肥应用技术等。4)随着遗传工程、合成生物学、宏基因组学、转录组学等技术方法的应用以及多学科的交叉研究,更深入探究生物固氮的机理并将其应用到农业生产中,对于减轻农业生产对工业氮肥的依赖,实现绿色低碳农业生产具有重要意义。展开更多
Background:Fructose may induce non-alcoholic fatty acids(NAFLD)due to the gut-liver axis interactions.The mechanism of fructose impairing colon barrier is unrevealed.Methods:Normal and dextran sulfate sodium(DSS)-indu...Background:Fructose may induce non-alcoholic fatty acids(NAFLD)due to the gut-liver axis interactions.The mechanism of fructose impairing colon barrier is unrevealed.Methods:Normal and dextran sulfate sodium(DSS)-induced Sprague-Dawley rats fed by 35%fructose diets were used to evaluate colon barrier functions.Microbiome and metabolome were applied to screen potential biomarker bacteria and metabolites induced by fructose.HT-29 cells were applied to validate metabolite biomarker indoleacrylic acid(IAA)and indole-3-carboxaldehyde(I3A)function in colon barrier which impaired by fructose.Results:Fructose induced colon barrier dysfunction,aggravated colon impairment in DSS-induced rats.With fructose intake,the colon length shortened,goblet numbers declined,inflammation infiltration induced,inflammatory cytokines increased,and apoptosis signals upregulated in colon tissue.Moreover,fructose induced dysbiosis of microbiota and their metabolites.Adlercreutzia and Holdemania were screened out as potential bacteria biomarkers,IAA and I3A as tryptophan metabolites were selected as metabolite biomarkers inhibited by fructose.IAA and I3A treatment alleviated the impairment induced by fructose by increasing trans epithelial electric resistance value,tight junction proteins,and Aryl hydrocarbon receptor(Ah R)activity in HT-29 cell.Conclusion:Fructose stimulated inflammation,apoptosis,gut bacteria alteration,and induced the reduction of IAA and I3A.Since fructose inhibited production of IAA and I3A,Ah R remained inactivated and consequently induced colon barrier dysfunction.展开更多
Structured illumination,a wide-field imaging approach used in microscopy to enhance image resolution beyond the system's diffraction limits,is a well-studied technique that has gained significant traction over the...Structured illumination,a wide-field imaging approach used in microscopy to enhance image resolution beyond the system's diffraction limits,is a well-studied technique that has gained significant traction over the last two decades.However,when translated to endoscopic systems,severe deformations of illumination patterns occur due to the large depth of field(DOF)and the 3D nature of the targets,introducing significant implementation challenges.Hence,this study explores a speckle-based system that best suits endoscopic practices to enhance image resolution by using random illumination patterns.The study presents a prototypic model of an endoscopic add-on,its design,and fabrication facilitated by using the speckle structured illumination endoscopic(SSIE)system.The imaging results of the SSIE are explained on a colon phantom model at different imaging planes with a wide field of view(FOV)and DOF.The obtained imaging metrics are elucidated and compared with state-of-the-art(SOA)high-resolution endoscopic techniques.Moreover,the potential for a clinical translation of the prototypic SSIE model is also explored in this work.The incorporation of the add-on and its subsequent results on the colon phantom model could potentially pave the way for its successful integration and use in futuristic clinical endoscopic trials.展开更多
Whole-grain foods have attracted emerging attention due to their health benefits.Whole grains are rich in bound polyphenols(BPs)linked with dietary fibers,which is largely underestimated compared with free polyphenols...Whole-grain foods have attracted emerging attention due to their health benefits.Whole grains are rich in bound polyphenols(BPs)linked with dietary fibers,which is largely underestimated compared with free polyphenols.In this study,in vitro simulated gastrointestinal digestion and colonic fermentation models were used to study the release profile and metabolism of BPs of oat bran.Significantly higher level of BPs was released during in vitro colon fermentation(3.05 mg GAE/g)than in gastrointestinal digestion(0.54 mg GAE/g).Five polyphenols were detected via LC-MS and their possible conversion pathways were speculated.Released BPs exhibited chemical antioxidant capacity.16S rRNA sequencing further revealed that Clostridium butyricum,Enterococcus faecalis,Bacteroides acidifaciens were the key bacteria involved in the release of BPs,and this was verified by whole-cell transformation.Our results helped to explain the possible mechanism of the health benefits of BPs in whole grains.展开更多
Oxidized cholesterol(OXC)is a harmful dietary substance.Although the consumption of OXC has been associated with colonic inflammation,related underlying mechanisms are still limited.We evaluated the influence of dieta...Oxidized cholesterol(OXC)is a harmful dietary substance.Although the consumption of OXC has been associated with colonic inflammation,related underlying mechanisms are still limited.We evaluated the influence of dietary OXC on gut health and ecology by applying the murine model.Results showed that the thickness of the mucus layer was significantly reduced in healthy mice treated with OXC.Short-term intake of OXC did not influence the expression of pro-inflammatory factors in healthy mice but it induced the decrease of Muc2 expression in the proximal colon,accompanied by an increase in the abundance of 2 mucusdegrading bacteria,namely Akkermansia muciniphila and Bacteroides acidifaciens.Consistently,oral exposure of OXC promoted mucus barrier erosion in dextran sulfate sodium(DSS)-induced colitis mice and facilitated bacteria infiltration in the colon.The adverse effect of OXC on mucus layer disappeared in antibiotics-treated healthy mice,suggesting that the damaging effect of OXC on the gut mucus layer was not direct and instead was mediated by causing microbiota dysbiosis.Finally,the impact of OXC on the mucus layer and colitis was partly alleviated by green tea catechins.These studies demonstrated that the OXC-induced mucus barrier damage was mainly induced by the dysregulation of gut microbiota at least in this mouse model.展开更多
文摘为系统了解国内外生物固氮的研究现状,本研究基于在Web of Science(WOS)核心合集数据库及中国知网(CNKI)检索的1990—2023年有关生物固氮研究的文献,利用Citespace、VOSviewer、HistCite等文献计量工具,对发文数量、主要国家(地区)与机构、主要发文期刊和研究学者、重要文献、研究热点以及研究变化趋势等进行了计量分析。结果表明,1)近24年来,生物固氮研究领域发文量呈逐年增多趋势,2010年后中国发文占比显著增多,并成为WOS数据库中生物固氮领域发文量排名第2的国家,且与美国、巴西、德国等发文量较多的国家之间联系密切。植物科学、微生物学是英文发文量较多的学科,生物学、作物学是中文发文量较多的学科,都与农业科学紧密相关。生物固氮相关研究的中英文论文主要发文期刊是《生物技术通报》、《Plant and Soil》、《Soil Biology&Biochemistry》。Hungria M、Urquiaga S、Boddey R M和李友国是该领域发文较多的研究学者。2)生物固氮关键词聚类网络主要可分为生物固氮相关微生物及其定殖,生物固氮对农业生产的影响,生物固氮分子机理,以及生物固氮影响因素等4类,如何提升生物固氮效率并扩大其应用范围成为研究者关注的焦点。3)生物固氮研究近些年的主要挑战包括:扩大根瘤菌宿主范围,提高根际联合固氮效率;将生物固氮引入禾谷类作物中,开发“氮肥自供型”作物;挖掘高效固氮微生物资源,优化菌肥应用技术等。4)随着遗传工程、合成生物学、宏基因组学、转录组学等技术方法的应用以及多学科的交叉研究,更深入探究生物固氮的机理并将其应用到农业生产中,对于减轻农业生产对工业氮肥的依赖,实现绿色低碳农业生产具有重要意义。
基金supported by the Special Funds of Basic Research of Central Public Welfare Institute(JY2010 and ZX2410)。
文摘Background:Fructose may induce non-alcoholic fatty acids(NAFLD)due to the gut-liver axis interactions.The mechanism of fructose impairing colon barrier is unrevealed.Methods:Normal and dextran sulfate sodium(DSS)-induced Sprague-Dawley rats fed by 35%fructose diets were used to evaluate colon barrier functions.Microbiome and metabolome were applied to screen potential biomarker bacteria and metabolites induced by fructose.HT-29 cells were applied to validate metabolite biomarker indoleacrylic acid(IAA)and indole-3-carboxaldehyde(I3A)function in colon barrier which impaired by fructose.Results:Fructose induced colon barrier dysfunction,aggravated colon impairment in DSS-induced rats.With fructose intake,the colon length shortened,goblet numbers declined,inflammation infiltration induced,inflammatory cytokines increased,and apoptosis signals upregulated in colon tissue.Moreover,fructose induced dysbiosis of microbiota and their metabolites.Adlercreutzia and Holdemania were screened out as potential bacteria biomarkers,IAA and I3A as tryptophan metabolites were selected as metabolite biomarkers inhibited by fructose.IAA and I3A treatment alleviated the impairment induced by fructose by increasing trans epithelial electric resistance value,tight junction proteins,and Aryl hydrocarbon receptor(Ah R)activity in HT-29 cell.Conclusion:Fructose stimulated inflammation,apoptosis,gut bacteria alteration,and induced the reduction of IAA and I3A.Since fructose inhibited production of IAA and I3A,Ah R remained inactivated and consequently induced colon barrier dysfunction.
文摘Structured illumination,a wide-field imaging approach used in microscopy to enhance image resolution beyond the system's diffraction limits,is a well-studied technique that has gained significant traction over the last two decades.However,when translated to endoscopic systems,severe deformations of illumination patterns occur due to the large depth of field(DOF)and the 3D nature of the targets,introducing significant implementation challenges.Hence,this study explores a speckle-based system that best suits endoscopic practices to enhance image resolution by using random illumination patterns.The study presents a prototypic model of an endoscopic add-on,its design,and fabrication facilitated by using the speckle structured illumination endoscopic(SSIE)system.The imaging results of the SSIE are explained on a colon phantom model at different imaging planes with a wide field of view(FOV)and DOF.The obtained imaging metrics are elucidated and compared with state-of-the-art(SOA)high-resolution endoscopic techniques.Moreover,the potential for a clinical translation of the prototypic SSIE model is also explored in this work.The incorporation of the add-on and its subsequent results on the colon phantom model could potentially pave the way for its successful integration and use in futuristic clinical endoscopic trials.
基金the support from the research grants by National Natural Science Foundation of China(32202051)National Key R&D Program of China(2022YFF1100104)the Major Project of Inner Mongolia Science and Technology Department,China(2021ZD0002)。
文摘Whole-grain foods have attracted emerging attention due to their health benefits.Whole grains are rich in bound polyphenols(BPs)linked with dietary fibers,which is largely underestimated compared with free polyphenols.In this study,in vitro simulated gastrointestinal digestion and colonic fermentation models were used to study the release profile and metabolism of BPs of oat bran.Significantly higher level of BPs was released during in vitro colon fermentation(3.05 mg GAE/g)than in gastrointestinal digestion(0.54 mg GAE/g).Five polyphenols were detected via LC-MS and their possible conversion pathways were speculated.Released BPs exhibited chemical antioxidant capacity.16S rRNA sequencing further revealed that Clostridium butyricum,Enterococcus faecalis,Bacteroides acidifaciens were the key bacteria involved in the release of BPs,and this was verified by whole-cell transformation.Our results helped to explain the possible mechanism of the health benefits of BPs in whole grains.
基金supported by Hong Kong Research Grants Council General Research Fund(CUHK 14102321,14103722 and 14104923)。
文摘Oxidized cholesterol(OXC)is a harmful dietary substance.Although the consumption of OXC has been associated with colonic inflammation,related underlying mechanisms are still limited.We evaluated the influence of dietary OXC on gut health and ecology by applying the murine model.Results showed that the thickness of the mucus layer was significantly reduced in healthy mice treated with OXC.Short-term intake of OXC did not influence the expression of pro-inflammatory factors in healthy mice but it induced the decrease of Muc2 expression in the proximal colon,accompanied by an increase in the abundance of 2 mucusdegrading bacteria,namely Akkermansia muciniphila and Bacteroides acidifaciens.Consistently,oral exposure of OXC promoted mucus barrier erosion in dextran sulfate sodium(DSS)-induced colitis mice and facilitated bacteria infiltration in the colon.The adverse effect of OXC on mucus layer disappeared in antibiotics-treated healthy mice,suggesting that the damaging effect of OXC on the gut mucus layer was not direct and instead was mediated by causing microbiota dysbiosis.Finally,the impact of OXC on the mucus layer and colitis was partly alleviated by green tea catechins.These studies demonstrated that the OXC-induced mucus barrier damage was mainly induced by the dysregulation of gut microbiota at least in this mouse model.
