Germ-free mice exhibit profound immunological immaturity.Despite recent studies emphasizing the role of specific bacterium-derived metabolites in immune cell development and differentiation,the mechanisms linking micr...Germ-free mice exhibit profound immunological immaturity.Despite recent studies emphasizing the role of specific bacterium-derived metabolites in immune cell development and differentiation,the mechanisms linking microbiota absence to systemic immune deficits remain incompletely defined.Here,droplet-based single-cell RNA sequencing of bone marrow and peripheral blood from both germ-free and specific pathogen-free mice was performed,identifying 25 transcriptionally distinct cell types.Neutrophil apoptosis was elevated in germ-free mice,potentially due to the absence of niacin dehydrogenase,a metabolite primarily produced by Pseudomonas.In addition,germ-free mice exhibited increased excretion of 5’-methylthioadenosine,enhanced ERK activation driven by reactive oxygen species,and disruption of bone marrow stromal antigen 2 signaling.Monocytes and CD8^(+)T cells from germ-free mice showed diminished responses to interferon-β and interferon-γ,consistent with heightened viral susceptibility.These findings establish a microbiota-dependent regulatory pathway linking immunodeficiency to microbial absence in germ-free mice,confirmed through complementary validation techniques.展开更多
As a traditional herbal medicine,the major alkaloids in Uncaria rhynchophylla have been proven to have blood pressure-lowering and sedative effects.It is essential to develop an effective method for the determination ...As a traditional herbal medicine,the major alkaloids in Uncaria rhynchophylla have been proven to have blood pressure-lowering and sedative effects.It is essential to develop an effective method for the determination of the major alkaloids in U.rhynchophylla.In this research,a rapid quantitative analysis involving multi-components analysis by a single marker strategy coupled with core-shell column HPLC was adopted to analyse four alkaloids(corynoxeine,isocorynoxeine,isorhynchophylline,rhynchophylline)in U.rhynchophylla.Isorhynchophylline was selected as the internal reference substance,the content of which was determined by the traditional external standard method.Relative correction factors(RCF)between isorhynchophylline and the other three alkaloids were calculated respectively.The results showed that the QAMS method had good robustness under different HPLC instruments.Nineteen batches of U.rhynchophylla were tested.No significant difference was observed between the results by QAMS and EMS(Correlation coefficient>0.99,p>0.05).The QAMS method could be employed as a rapid,effective technique for the quality control of U.rhynchophylla.展开更多
Prohibited pesticide residues have become one of the main factors affecting the quality and safety of Lycii Fructus,However,rarely studies focus on the rapid determination of these residues.Here,a total of 30 kinds of...Prohibited pesticide residues have become one of the main factors affecting the quality and safety of Lycii Fructus,However,rarely studies focus on the rapid determination of these residues.Here,a total of 30 kinds of prohibited pesticide residues were determined by ultra-performance liquid chromatography tandem triple quadrupole mass spectrometry(UPLC-MS/MS)in five different process ways.Pretreatment methods,chromatographic separation and detection conditions in mass spectrometry were all optimized accordingly.Among the five different pretreatment methods,the first and third solid phase extraction failed to provide high recoveries of sulfosulfuron compounds(both lower than 60%).Recovery of chlorphenamidine by the Quick Easy Cheap Effective Rugged and Safe multiresidue method(QuEChERS)was lower than 60%,which did not meet the requirements of trace determination.The concentrations of 30 prohibited pesticides residues treated by straightforward and solid phase extraction showed good linearity in their corresponding ranges,with correlation coefficients over 0.99.The average recoveries of straightforward ranged from 78.13%to 110.9%,while RSD ranged from 1.3%to 16.9%,albeit poor purification was observed.The recovery yield from solid phase extraction was between 67.75%and 103.08%with RSD value from 0.8%to 14.0%,which met the requirements of trace determination,this method has good precision and stability.These results could be employed to other Traditional Chinese Medicines(TCMs)in detecting prohibited pesticide residues.展开更多
基金supported by the Science Technology and Innovation Commission of Shenzhen Municipality,China(SGCX20190919142801722)。
文摘Germ-free mice exhibit profound immunological immaturity.Despite recent studies emphasizing the role of specific bacterium-derived metabolites in immune cell development and differentiation,the mechanisms linking microbiota absence to systemic immune deficits remain incompletely defined.Here,droplet-based single-cell RNA sequencing of bone marrow and peripheral blood from both germ-free and specific pathogen-free mice was performed,identifying 25 transcriptionally distinct cell types.Neutrophil apoptosis was elevated in germ-free mice,potentially due to the absence of niacin dehydrogenase,a metabolite primarily produced by Pseudomonas.In addition,germ-free mice exhibited increased excretion of 5’-methylthioadenosine,enhanced ERK activation driven by reactive oxygen species,and disruption of bone marrow stromal antigen 2 signaling.Monocytes and CD8^(+)T cells from germ-free mice showed diminished responses to interferon-β and interferon-γ,consistent with heightened viral susceptibility.These findings establish a microbiota-dependent regulatory pathway linking immunodeficiency to microbial absence in germ-free mice,confirmed through complementary validation techniques.
文摘As a traditional herbal medicine,the major alkaloids in Uncaria rhynchophylla have been proven to have blood pressure-lowering and sedative effects.It is essential to develop an effective method for the determination of the major alkaloids in U.rhynchophylla.In this research,a rapid quantitative analysis involving multi-components analysis by a single marker strategy coupled with core-shell column HPLC was adopted to analyse four alkaloids(corynoxeine,isocorynoxeine,isorhynchophylline,rhynchophylline)in U.rhynchophylla.Isorhynchophylline was selected as the internal reference substance,the content of which was determined by the traditional external standard method.Relative correction factors(RCF)between isorhynchophylline and the other three alkaloids were calculated respectively.The results showed that the QAMS method had good robustness under different HPLC instruments.Nineteen batches of U.rhynchophylla were tested.No significant difference was observed between the results by QAMS and EMS(Correlation coefficient>0.99,p>0.05).The QAMS method could be employed as a rapid,effective technique for the quality control of U.rhynchophylla.
文摘Prohibited pesticide residues have become one of the main factors affecting the quality and safety of Lycii Fructus,However,rarely studies focus on the rapid determination of these residues.Here,a total of 30 kinds of prohibited pesticide residues were determined by ultra-performance liquid chromatography tandem triple quadrupole mass spectrometry(UPLC-MS/MS)in five different process ways.Pretreatment methods,chromatographic separation and detection conditions in mass spectrometry were all optimized accordingly.Among the five different pretreatment methods,the first and third solid phase extraction failed to provide high recoveries of sulfosulfuron compounds(both lower than 60%).Recovery of chlorphenamidine by the Quick Easy Cheap Effective Rugged and Safe multiresidue method(QuEChERS)was lower than 60%,which did not meet the requirements of trace determination.The concentrations of 30 prohibited pesticides residues treated by straightforward and solid phase extraction showed good linearity in their corresponding ranges,with correlation coefficients over 0.99.The average recoveries of straightforward ranged from 78.13%to 110.9%,while RSD ranged from 1.3%to 16.9%,albeit poor purification was observed.The recovery yield from solid phase extraction was between 67.75%and 103.08%with RSD value from 0.8%to 14.0%,which met the requirements of trace determination,this method has good precision and stability.These results could be employed to other Traditional Chinese Medicines(TCMs)in detecting prohibited pesticide residues.
