Objective： To establish an animal model of P.aeruginosa biofilm associated with chronic pulmonary infection and investigate the pathogenic effects of biofilm. Methods： Experiments in vitro, measuring the MICS, MBCS ...Objective： To establish an animal model of P.aeruginosa biofilm associated with chronic pulmonary infection and investigate the pathogenic effects of biofilm. Methods： Experiments in vitro, measuring the MICS, MBCS of levofloxacin（LFX）, ceftazidime（CAZ） in PAO579 in alginate beads and planktonic PAO579. Rats were challenged with 0.1 ml of PAO579（109CFU/ml） in alginate beads or 0.1 ml of planktonic PAO579（109CFU/ml）, 3,7,14 days after challenging, bacteriological, pathological features were observed. Results： The MICS, MBCS of LFX, CAZ in PAO579 in alginate beads were higher than those in planktonic PAO579 in vitro. CFU/lung in alginate beads group was significantly higher than that in planktonic bacteria group（P = 0.002, P = 0.004, P = 0.002, respectively）; macroscopic lung pathology and the inflammation in alginate beads group were significantly more severe compared to those in planktonic bacteria group in vivo. Conclusion： P.aeruginosa biofilm protected bacterium from killing of antibiotics and might mediate the host immune damage in the lung tissue and made bacterium evade the host immune defense.展开更多
This paper aims to research the effects of combined application of humic acid and urea on the wheat yield and yield component,and establish rational fertilizer application scheme of wheat. Split plot experiment was ad...This paper aims to research the effects of combined application of humic acid and urea on the wheat yield and yield component,and establish rational fertilizer application scheme of wheat. Split plot experiment was adopted. Two types of phosphorus fertilizer( adding humic acid or not) was assigned to the main plot,and four types of top dressing modes( different amount of urea and humic acid urea) were used in subplots. Effects of combined application of humic acid and urea on the wheat yield and yield component were researched. 375 kg / ha ordinary DAP + 150 kg / ha urea was used as base fertilizer; topdressing of 300 kg / ha urea humate could effectively promote the plant height,leaf area coefficient and aboveground dry matter amount. Adding humic acid in urea in topdressing significantly enhanced the wheat yield and economic coefficient of wheat. Adding humic acid in urea in topdressing has better effects of yield increasing than base fertilizer,and can be used for large scale extension.展开更多
Astragalosides are the main active constituents of traditional Chinese medicine Huang-Qi,of which cycloastragenol-type glycosides are the most typical and major bioactive compounds.This kind of compounds exhibit vario...Astragalosides are the main active constituents of traditional Chinese medicine Huang-Qi,of which cycloastragenol-type glycosides are the most typical and major bioactive compounds.This kind of compounds exhibit various biological functions including cardiovascular protective,neuroprotective,etc.Owing to the limitations of natural sources and the difficulties encountered in chemical synthesis,re-engineering of biosynthetic machinery will offer an alternative and promising approach to producing astragalosides.However,the biosynthetic pathway for astragalosides remains elusive due to their complex structures and numerous reaction types and steps.Herein,guided by transcriptome and phylogenetic analyses,a cycloartenol synthase and four glycosyltransferases catalyzing the committed steps in the biosynthesis of such bioactive astragalosides were functionally characterized from Astragalus membranaceus.AmCAS1,the first reported cycloartenol synthase from Astragalus genus,is capable of catalyzing the formation of cycloartenol;AmUGT15,AmUGT14,AmUGT13,and AmUGT7 are four glycosyltransferases biochemically characterized to catalyze 3-O-xylosylation,3-O-glucosylation,25-O-glucosylation/O-xylosylation and 2’-O-glucosylation of cycloastragenol glycosides,respectively.These findings not only clarified the crucial enzymes for the biosynthesis and the molecular basis for the structural diversity of astragalosides in Astragalus plants,also paved the way for further completely deciphering the biosynthetic pathway and constructing an artificial pathway for their efficient production.展开更多
Microbes serve as the most important resource for drug discovery.During our screening for bioactive compounds from our natural products library,a pathogenic fungus,Microdochium majus strain 99049,from wheat was select...Microbes serve as the most important resource for drug discovery.During our screening for bioactive compounds from our natural products library,a pathogenic fungus,Microdochium majus strain 99049,from wheat was selected for further investigation.A new alkaloid named brocaeloid D(1),together with six previously characterized compounds(2–7)were identified.Compound 1 belongs to 4-oxoquinoline with C-2 reversed prenylation and a succinimide substructure.All the structures of these newly isolated compounds were determined by different means in spectroscopic experiments.The absolute configurations of 1 was further deduced from comparison of its CD spectrum with that of known compound 2.The bioactivities of these identified compounds were evaluated against several pathogenic microorganisms and cancer cell lines.Compounds 1–5 showed activity against HUH-7 human hepatoma cells with IC50 values of 80μg/mL.Compound 6 showed mild activity against HeLa cells(IC50=51.9μg/mL),weak anti-MTB activity(MIC=80μg/mL),and moderate anti-MRSA activity(MIC=25μg/mL),and compound 7 showed weak anti-MRSA activity(MIC=100μg/mL).展开更多
OBJECTIVE: To summarized the antimicrobial-like effects of Radix Ginseng, which provide important information to the relevant researchers and clinicians, and will benefit the clinical treatment of infectious diseases....OBJECTIVE: To summarized the antimicrobial-like effects of Radix Ginseng, which provide important information to the relevant researchers and clinicians, and will benefit the clinical treatment of infectious diseases.METHODS: PubMed and Google were used to search for and collect scientific publications related to Radix Ginseng and microbial infections. The authors read, classified, and discussed the associated scientific results or evidences, and summarized the corresponding results.RESULTS: In this review, recent studies on the bene-ficial effects of Radix Ginseng extracts on microbial and biofilm infections were reviewed. The importance and significance of Radix Ginseng's beneficial effects are discussed. Evidence for the favorable effects of Radix Ginseng extracts on viral, bacterial,fungal, and parasitic infections and the possible underlying mechanisms are summarized.CONCLUSION: Radix Ginseng might be a promising supplemental remedy for the prevention and treatment of infectious diseases.展开更多
基金National Nature Science Associate Fundation(NSAF) of China (30760084)
文摘Objective： To establish an animal model of P.aeruginosa biofilm associated with chronic pulmonary infection and investigate the pathogenic effects of biofilm. Methods： Experiments in vitro, measuring the MICS, MBCS of levofloxacin（LFX）, ceftazidime（CAZ） in PAO579 in alginate beads and planktonic PAO579. Rats were challenged with 0.1 ml of PAO579（109CFU/ml） in alginate beads or 0.1 ml of planktonic PAO579（109CFU/ml）, 3,7,14 days after challenging, bacteriological, pathological features were observed. Results： The MICS, MBCS of LFX, CAZ in PAO579 in alginate beads were higher than those in planktonic PAO579 in vitro. CFU/lung in alginate beads group was significantly higher than that in planktonic bacteria group（P = 0.002, P = 0.004, P = 0.002, respectively）; macroscopic lung pathology and the inflammation in alginate beads group were significantly more severe compared to those in planktonic bacteria group in vivo. Conclusion： P.aeruginosa biofilm protected bacterium from killing of antibiotics and might mediate the host immune damage in the lung tissue and made bacterium evade the host immune defense.
基金Supported by National Modern Agricultural Industrial Technological System Foundation of the Ministry of Agriculture(CARS-3)
文摘This paper aims to research the effects of combined application of humic acid and urea on the wheat yield and yield component,and establish rational fertilizer application scheme of wheat. Split plot experiment was adopted. Two types of phosphorus fertilizer( adding humic acid or not) was assigned to the main plot,and four types of top dressing modes( different amount of urea and humic acid urea) were used in subplots. Effects of combined application of humic acid and urea on the wheat yield and yield component were researched. 375 kg / ha ordinary DAP + 150 kg / ha urea was used as base fertilizer; topdressing of 300 kg / ha urea humate could effectively promote the plant height,leaf area coefficient and aboveground dry matter amount. Adding humic acid in urea in topdressing significantly enhanced the wheat yield and economic coefficient of wheat. Adding humic acid in urea in topdressing has better effects of yield increasing than base fertilizer,and can be used for large scale extension.
基金supported by the National Key Research and Development Program of China(2020YFA0908000)CAMS Innovation fund for Medical Sciences(CIFMS,No.2021-I2M-1029,China)Beijing Key Laboratory of non-Clinical Drug Metabolism and PK/PD Study(Z141102004414062)。
文摘Astragalosides are the main active constituents of traditional Chinese medicine Huang-Qi,of which cycloastragenol-type glycosides are the most typical and major bioactive compounds.This kind of compounds exhibit various biological functions including cardiovascular protective,neuroprotective,etc.Owing to the limitations of natural sources and the difficulties encountered in chemical synthesis,re-engineering of biosynthetic machinery will offer an alternative and promising approach to producing astragalosides.However,the biosynthetic pathway for astragalosides remains elusive due to their complex structures and numerous reaction types and steps.Herein,guided by transcriptome and phylogenetic analyses,a cycloartenol synthase and four glycosyltransferases catalyzing the committed steps in the biosynthesis of such bioactive astragalosides were functionally characterized from Astragalus membranaceus.AmCAS1,the first reported cycloartenol synthase from Astragalus genus,is capable of catalyzing the formation of cycloartenol;AmUGT15,AmUGT14,AmUGT13,and AmUGT7 are four glycosyltransferases biochemically characterized to catalyze 3-O-xylosylation,3-O-glucosylation,25-O-glucosylation/O-xylosylation and 2’-O-glucosylation of cycloastragenol glycosides,respectively.These findings not only clarified the crucial enzymes for the biosynthesis and the molecular basis for the structural diversity of astragalosides in Astragalus plants,also paved the way for further completely deciphering the biosynthetic pathway and constructing an artificial pathway for their efficient production.
基金This work was partially supported by the grants from the National Natural Science Foundation of China(31430002,81573341,21877038,31720103901,31320103911)Taishan Scholarship,Open Project Funding of the State Key Laboratory of Bioreactor Engineering,the 111 Project(B18022)+1 种基金National Key R&D Program of China 2017YFE0108200the Fundamental Research Funds for the Central Universities(22221818014).
文摘Microbes serve as the most important resource for drug discovery.During our screening for bioactive compounds from our natural products library,a pathogenic fungus,Microdochium majus strain 99049,from wheat was selected for further investigation.A new alkaloid named brocaeloid D(1),together with six previously characterized compounds(2–7)were identified.Compound 1 belongs to 4-oxoquinoline with C-2 reversed prenylation and a succinimide substructure.All the structures of these newly isolated compounds were determined by different means in spectroscopic experiments.The absolute configurations of 1 was further deduced from comparison of its CD spectrum with that of known compound 2.The bioactivities of these identified compounds were evaluated against several pathogenic microorganisms and cancer cell lines.Compounds 1–5 showed activity against HUH-7 human hepatoma cells with IC50 values of 80μg/mL.Compound 6 showed mild activity against HeLa cells(IC50=51.9μg/mL),weak anti-MTB activity(MIC=80μg/mL),and moderate anti-MRSA activity(MIC=25μg/mL),and compound 7 showed weak anti-MRSA activity(MIC=100μg/mL).
文摘OBJECTIVE: To summarized the antimicrobial-like effects of Radix Ginseng, which provide important information to the relevant researchers and clinicians, and will benefit the clinical treatment of infectious diseases.METHODS: PubMed and Google were used to search for and collect scientific publications related to Radix Ginseng and microbial infections. The authors read, classified, and discussed the associated scientific results or evidences, and summarized the corresponding results.RESULTS: In this review, recent studies on the bene-ficial effects of Radix Ginseng extracts on microbial and biofilm infections were reviewed. The importance and significance of Radix Ginseng's beneficial effects are discussed. Evidence for the favorable effects of Radix Ginseng extracts on viral, bacterial,fungal, and parasitic infections and the possible underlying mechanisms are summarized.CONCLUSION: Radix Ginseng might be a promising supplemental remedy for the prevention and treatment of infectious diseases.
