Background Enterobacterial translocation is a leading contributor to fatal infection among patients with acute ischaemic stroke(AIS).Accumulative evidence suggests that mesenchymal stem cell(MSC)effectively ameliorate...Background Enterobacterial translocation is a leading contributor to fatal infection among patients with acute ischaemic stroke(AIS).Accumulative evidence suggests that mesenchymal stem cell(MSC)effectively ameliorates stroke outcomes.Whether MSC could inhibit post-stroke enterobacterial translocation remains elusive.Methods Patients with AIS and healthy individuals were enrolled in the study.Mice subjected to transient middle cerebral artery occlusion were treated with bone marrow-derived MSC(BM-MSC)right after reperfusion.Enterobacterial translocation was evaluated with Stroke Dysbiosis Index and circulating endotoxin.Thickness of mucus was assessed with Alcian blue staining.Hepatic glucocorticoid(GC)metabolism was analysed with expression of HSD11B2,HSD11B1 and SRD5A1.Results We report that the gut mucus layer was attenuated after the stroke leading to pronounced enterobacterial translocation.The attenuation of the gut mucus was attributed to diminished mucin production by goblet cells in response to the elevated systemic GC after cerebral ischaemia.Transferred-BM MSC restored the mucus thickness,thus preserving gut microbiota homeostasis and preventing enterobacterial invasion.Mechanistically,the transferred-BM MSC stationed in the liver and enhanced peroxisome proliferator-activated receptorγsignalling in hepatocytes.Consequently,expression of HSD11B2 and SRD5A1 was increased while HSD11B1 expression was downregulated which promoted GC catabolism and subsequently restored mucin production.Conclusions Our findings reveal that MSC transfer improves post-stroke gut barrier integrity and inhibits enterobacterial translocation by enhancing the hepatic GC metabolism thus representing a protective modulator of the liver-gut brain axis in AIS.展开更多
AIM:To find a rapid and efficient analysis method of gastrointestinal microflora in Pi-deficient(spleen-deficient) rats and to evaluate traditional Chinese drugs.METHODS:Enterobacterial repetitive intergenic consensus...AIM:To find a rapid and efficient analysis method of gastrointestinal microflora in Pi-deficient(spleen-deficient) rats and to evaluate traditional Chinese drugs.METHODS:Enterobacterial repetitive intergenic consensus-PCR(ERIC-PCR) based assay was performed to examine changes of intestinal microflora in two Pi-deficienct animal models and to evaluate the efficacy of four traditional Chinese drugs as well as a probiotic recipe and another therapy in Pi-deficient rats.RESULTS:A molecular marker was identified for Pi-deficiency in rats.The pharmacodynamic evaluation system,including identified molecular markers(net integral area and abundance of DNA bands),Shannon's index for diversity of intestinal microflora,and Sorenson's pairwise similarity coefficient,was established.The four major clinical recipes of traditional Chinese drugs for Pi-deficiency in rats,especially at their medium dose(equivalence to the clinical dose),produced more pronounced recovery activities in Pi-deficient rats,while higher doses of these recipes did not show a better therapeutic effect but some toxic effects such as perturbation deterioration of intestinal microflora.CONCLUSION:Both fingerprint analysis and identified marker can show Pi-deficiency in rats and its difference after treatment.The identified molecular marker may be applied in screening for the active compounds both in relative traditional Chinese drugs and in pharmacodynamic study of Pi-deficiency in rats.展开更多
Chlorpyrifos is a widely used insecticide in recent years,and it will produce adverse effects on soil when applied on crops or mixed with soil.In this study,nested polymerase chain reaction（PCR） and denaturing gradi...Chlorpyrifos is a widely used insecticide in recent years,and it will produce adverse effects on soil when applied on crops or mixed with soil.In this study,nested polymerase chain reaction（PCR） and denaturing gradient gel electrophoresis（DGGE） were combined to explore the bacterial and fungal community successions in soil treated with 5 and 20 mg/kg of chlorpyrifos.Furthermore,isolates capable of efficiently decomposing chlorpyrifos were molecular-typed using enterobacterial repetitive intergenic consensus-PCR（ERIC-PCR）.Under the experimental conditions,degradation of chlorpyrifos in soil was interpreted with the first-order kinetics,and the half-lives of chlorpyrifos at 5 and 20 mg/kg doses were calculated to be 8.25 and 8.29 d,respectively.DGGE fingerprint and principal component analysis（PCA） indicated that the composition of the fungal community was obviously changed with the chlorpyrifos treatment,and that samples of chlorpyrifos treatment were significantly separated from those of the control from the beginning to the end.While for the bacterial community,chlorpyrifos-treated soil samples were apparently different in the first 30 d and recovered to a similar level of the control up until 60 d,and the distance in the PCA between the chlorpyrifos-treated samples and the control was getting shorter through time and was finally clustered into one group.Together,our results demonstrated that the application of chlorpyrifos could affect the fungal community structure in a quick and lasting way,while only affecting the bacterial community in a temporary way.Finally,nine typical ERIC types of chlorpyrifos-degrading isolates were screened.展开更多
In order to reduce deleterious effect on environment,human health and facilities caused by original sulfides, more attention should be paid to biodesulfurization studying for fossil fuels. In this work, eight isolates...In order to reduce deleterious effect on environment,human health and facilities caused by original sulfides, more attention should be paid to biodesulfurization studying for fossil fuels. In this work, eight isolates were characterized by several DNA-based methods such as BOX element polymerase chain reaction( BOX-PCR), enterobacterial repetitive intergenic consensus( ERIC)-PCR and random amplification of polymorphic DNA( RAPD)-PCR. The desulfurization performance was determined by micro-coulometric method,Gibb's assay and barium sulfate test. It was found out that ERIC-PCR displays a much higher inter-strain heterogeneity compared with using BOX. The length of the primer didnot play the most important role in bacterial classification. The combination of the analysis of repetitive-sequence-based polymerase chain reaction ngerprinting and 16 S r DNA was able to provide more effective way in the separation and identification of bacteria.According to the analysis of 16 S r DNA,the more efficient desulfurization strain should belong to Klebsiella variicola.展开更多
Background:Bacterial diarrhea is one of the most common causes for medical consultations,mortality and morbidity in the world.Diarrheagenic Escherichia coli(DEC)and non-typhoidal Salmonella(NTS)are major intestinal pa...Background:Bacterial diarrhea is one of the most common causes for medical consultations,mortality and morbidity in the world.Diarrheagenic Escherichia coli(DEC)and non-typhoidal Salmonella(NTS)are major intestinal pathogens in developing countries,and the indiscriminate use of antibiotics has greatly contributed to resistant strains.Hence,the aim of the present study is to identify the antimicrobial resistance patterns and the molecular characteristics of DEC and NTS in southwest,China.Methods:1121 diarrheal patients and 319 non-diarrheal subjects across all age groups were recruited from four sentinel hospitals from June 2014 to July 2015 in Kunming City,Yunnan Province.Each stool specimen was collected to detect DEC and NTS with standard microbiological and molecular methods.Antimicrobial resistance testing was performed with the Kirby-Bauer disk diffusion method,and the standards for antimicrobial susceptibility testing complied with the Clinical and Laboratory Standards Institute(CLSI).Molecular characterization of strains was carried out using pulsed-field gel electrophoresis(PFGE).A structured questionnaire was used to record basic epidemiological data(e.g.sex,age,residence,season,etc.).Data were analyzed using Chi-square or Fisher’s exact test.Results:DEC was detected in 127(11.33%)diarrhea cases and 9(2.82%)non-diarrheal cases(χ^(2)=20.69,P<0.001,OR=4.36,95%CI:2.19-8.65),and the prevalence of NTS isolated from diarrhea cases was higher than that of non-diarrheal cases across all age groups(n=42,3.75%,n=1,0.31%,χ^(2)=10.10,P=0.002,OR=12.38,95%CI:1.70-90.29).The rates of resistance to ten antibiotics of DEC and NTS showed significant differences(χ^(2)=386.77,P<0.001;χ^(2)=191.16,P<0.001).The rates of resistance to Amoxicillin and Clavulafiate(AMC),Cephalothin(CEP),Gentamicin(GEN)and Sulfamethoxazole-Trimethoprim(SXT)of DEC isolated from diarrhea cases were higher than those of NTS isolated from diarrhea patients(37.01%vs 14.29%,χ^(2)=7.57,P=0.006;29.92%vs 11.90%,χ^(2)=5.40,P=0.02;37.01%vs 11.90%,χ^(2)=5.80,P=0.016;62.20%vs 26.19%,χ^(2)=16.44,P<0.001;respectively).Ciprofloxacin(CIP)was the most sensitive antibiotic for DEC and NTS strains isolated from diarrhea cases.Resistance rates of DEC isolates from cases and controls to more than three kinds antimicrobials(multidrug resistance,MDR)showed no significant differences(81.10%vs 88.89%,P=0.33).Pulsotype patterns of DEC strains were highly diverse;however,the pulsotype pattern of NTS strains was closely related to the serotype.The pattern of S.enteritidis was highly similar,but the S.enterica Typhimurium strain was discrete.Conclusions:Antibiotic resistance of Enterobacteriaceae is of great concern.The societal effects of antibiotic use justify strict monitoring to combat increases in antimicrobial resistance.Molecular epidemiology and systematic epidemiological investigation can provide accurate evidence for tracking the infection source.展开更多
基金supported by Guangzhou Key Research Program on Brain Science(202206060001 to ZL)Guangdong Basic and Applied Basic Research Foundation(2020A1515010056 to BZ)+3 种基金National Natural Science Foundation of China(82171307 to ZL)National Natural Science Foundation of China(82271348 to WC)Fundamental Research Funds for the Central Universities(23ykbj006 to WC)Science and Technology Program of Guangzhou(2023B01J1002 to ZL).
文摘Background Enterobacterial translocation is a leading contributor to fatal infection among patients with acute ischaemic stroke(AIS).Accumulative evidence suggests that mesenchymal stem cell(MSC)effectively ameliorates stroke outcomes.Whether MSC could inhibit post-stroke enterobacterial translocation remains elusive.Methods Patients with AIS and healthy individuals were enrolled in the study.Mice subjected to transient middle cerebral artery occlusion were treated with bone marrow-derived MSC(BM-MSC)right after reperfusion.Enterobacterial translocation was evaluated with Stroke Dysbiosis Index and circulating endotoxin.Thickness of mucus was assessed with Alcian blue staining.Hepatic glucocorticoid(GC)metabolism was analysed with expression of HSD11B2,HSD11B1 and SRD5A1.Results We report that the gut mucus layer was attenuated after the stroke leading to pronounced enterobacterial translocation.The attenuation of the gut mucus was attributed to diminished mucin production by goblet cells in response to the elevated systemic GC after cerebral ischaemia.Transferred-BM MSC restored the mucus thickness,thus preserving gut microbiota homeostasis and preventing enterobacterial invasion.Mechanistically,the transferred-BM MSC stationed in the liver and enhanced peroxisome proliferator-activated receptorγsignalling in hepatocytes.Consequently,expression of HSD11B2 and SRD5A1 was increased while HSD11B1 expression was downregulated which promoted GC catabolism and subsequently restored mucin production.Conclusions Our findings reveal that MSC transfer improves post-stroke gut barrier integrity and inhibits enterobacterial translocation by enhancing the hepatic GC metabolism thus representing a protective modulator of the liver-gut brain axis in AIS.
基金Supported by The National Natural Science Foundation of China,No.90209059Supported by The National Natural Science Foundation of China,No.90409018
文摘AIM:To find a rapid and efficient analysis method of gastrointestinal microflora in Pi-deficient(spleen-deficient) rats and to evaluate traditional Chinese drugs.METHODS:Enterobacterial repetitive intergenic consensus-PCR(ERIC-PCR) based assay was performed to examine changes of intestinal microflora in two Pi-deficienct animal models and to evaluate the efficacy of four traditional Chinese drugs as well as a probiotic recipe and another therapy in Pi-deficient rats.RESULTS:A molecular marker was identified for Pi-deficiency in rats.The pharmacodynamic evaluation system,including identified molecular markers(net integral area and abundance of DNA bands),Shannon's index for diversity of intestinal microflora,and Sorenson's pairwise similarity coefficient,was established.The four major clinical recipes of traditional Chinese drugs for Pi-deficiency in rats,especially at their medium dose(equivalence to the clinical dose),produced more pronounced recovery activities in Pi-deficient rats,while higher doses of these recipes did not show a better therapeutic effect but some toxic effects such as perturbation deterioration of intestinal microflora.CONCLUSION:Both fingerprint analysis and identified marker can show Pi-deficiency in rats and its difference after treatment.The identified molecular marker may be applied in screening for the active compounds both in relative traditional Chinese drugs and in pharmacodynamic study of Pi-deficiency in rats.
基金supported by the Zhejiang Provincial Key Technology Innovation Team(No.2010R50028)the Hangzhou Science and Technology Development Program(No.20110232B11),China
文摘Chlorpyrifos is a widely used insecticide in recent years,and it will produce adverse effects on soil when applied on crops or mixed with soil.In this study,nested polymerase chain reaction（PCR） and denaturing gradient gel electrophoresis（DGGE） were combined to explore the bacterial and fungal community successions in soil treated with 5 and 20 mg/kg of chlorpyrifos.Furthermore,isolates capable of efficiently decomposing chlorpyrifos were molecular-typed using enterobacterial repetitive intergenic consensus-PCR（ERIC-PCR）.Under the experimental conditions,degradation of chlorpyrifos in soil was interpreted with the first-order kinetics,and the half-lives of chlorpyrifos at 5 and 20 mg/kg doses were calculated to be 8.25 and 8.29 d,respectively.DGGE fingerprint and principal component analysis（PCA） indicated that the composition of the fungal community was obviously changed with the chlorpyrifos treatment,and that samples of chlorpyrifos treatment were significantly separated from those of the control from the beginning to the end.While for the bacterial community,chlorpyrifos-treated soil samples were apparently different in the first 30 d and recovered to a similar level of the control up until 60 d,and the distance in the PCA between the chlorpyrifos-treated samples and the control was getting shorter through time and was finally clustered into one group.Together,our results demonstrated that the application of chlorpyrifos could affect the fungal community structure in a quick and lasting way,while only affecting the bacterial community in a temporary way.Finally,nine typical ERIC types of chlorpyrifos-degrading isolates were screened.
基金National Natural Science Foundations of China(Nos.41302079,21176145)Project of Shandong Province Higher Educational Science and Technology Program,China(No.J13LD54)
文摘In order to reduce deleterious effect on environment,human health and facilities caused by original sulfides, more attention should be paid to biodesulfurization studying for fossil fuels. In this work, eight isolates were characterized by several DNA-based methods such as BOX element polymerase chain reaction( BOX-PCR), enterobacterial repetitive intergenic consensus( ERIC)-PCR and random amplification of polymorphic DNA( RAPD)-PCR. The desulfurization performance was determined by micro-coulometric method,Gibb's assay and barium sulfate test. It was found out that ERIC-PCR displays a much higher inter-strain heterogeneity compared with using BOX. The length of the primer didnot play the most important role in bacterial classification. The combination of the analysis of repetitive-sequence-based polymerase chain reaction ngerprinting and 16 S r DNA was able to provide more effective way in the separation and identification of bacteria.According to the analysis of 16 S r DNA,the more efficient desulfurization strain should belong to Klebsiella variicola.
基金Pathogens identified were supported by the postdoctoral research funding of SX-Z from Guangzhou Women and Children’s Medical Center(5001–3001075)The field epidemiological investigation was supported from National Natural Science Foundation of China(Grant number:81473022)+2 种基金The antibiotic resistance testing and the experiment of molecular characterization of pathogens were supported by National Key Research and Development Project(No.2016YFC1202000)The data analysis was conducted by E.Serrano who was funded by the Spanish Ministerio de Economia y Competitividad(MINECO)through a Ramon y Cajal agreement(RYC-2016-21120)R.Tinoco-Torres was supported by a post-doctoral grant by the Portuguese Fundacao para a Ciencia e a Tecnologia FCT(SFRH/BPD/112482/2015).
文摘Background:Bacterial diarrhea is one of the most common causes for medical consultations,mortality and morbidity in the world.Diarrheagenic Escherichia coli(DEC)and non-typhoidal Salmonella(NTS)are major intestinal pathogens in developing countries,and the indiscriminate use of antibiotics has greatly contributed to resistant strains.Hence,the aim of the present study is to identify the antimicrobial resistance patterns and the molecular characteristics of DEC and NTS in southwest,China.Methods:1121 diarrheal patients and 319 non-diarrheal subjects across all age groups were recruited from four sentinel hospitals from June 2014 to July 2015 in Kunming City,Yunnan Province.Each stool specimen was collected to detect DEC and NTS with standard microbiological and molecular methods.Antimicrobial resistance testing was performed with the Kirby-Bauer disk diffusion method,and the standards for antimicrobial susceptibility testing complied with the Clinical and Laboratory Standards Institute(CLSI).Molecular characterization of strains was carried out using pulsed-field gel electrophoresis(PFGE).A structured questionnaire was used to record basic epidemiological data(e.g.sex,age,residence,season,etc.).Data were analyzed using Chi-square or Fisher’s exact test.Results:DEC was detected in 127(11.33%)diarrhea cases and 9(2.82%)non-diarrheal cases(χ^(2)=20.69,P<0.001,OR=4.36,95%CI:2.19-8.65),and the prevalence of NTS isolated from diarrhea cases was higher than that of non-diarrheal cases across all age groups(n=42,3.75%,n=1,0.31%,χ^(2)=10.10,P=0.002,OR=12.38,95%CI:1.70-90.29).The rates of resistance to ten antibiotics of DEC and NTS showed significant differences(χ^(2)=386.77,P<0.001;χ^(2)=191.16,P<0.001).The rates of resistance to Amoxicillin and Clavulafiate(AMC),Cephalothin(CEP),Gentamicin(GEN)and Sulfamethoxazole-Trimethoprim(SXT)of DEC isolated from diarrhea cases were higher than those of NTS isolated from diarrhea patients(37.01%vs 14.29%,χ^(2)=7.57,P=0.006;29.92%vs 11.90%,χ^(2)=5.40,P=0.02;37.01%vs 11.90%,χ^(2)=5.80,P=0.016;62.20%vs 26.19%,χ^(2)=16.44,P<0.001;respectively).Ciprofloxacin(CIP)was the most sensitive antibiotic for DEC and NTS strains isolated from diarrhea cases.Resistance rates of DEC isolates from cases and controls to more than three kinds antimicrobials(multidrug resistance,MDR)showed no significant differences(81.10%vs 88.89%,P=0.33).Pulsotype patterns of DEC strains were highly diverse;however,the pulsotype pattern of NTS strains was closely related to the serotype.The pattern of S.enteritidis was highly similar,but the S.enterica Typhimurium strain was discrete.Conclusions:Antibiotic resistance of Enterobacteriaceae is of great concern.The societal effects of antibiotic use justify strict monitoring to combat increases in antimicrobial resistance.Molecular epidemiology and systematic epidemiological investigation can provide accurate evidence for tracking the infection source.
