To investigate the distribution of the genes of two major metallo-β-1actamases (MBL;i.e.,IMP and VIM) and class 1 integrons (intI) in the clinical imipenem-resistant Pseudomonas aeruginosa, a total of 65 isolates...To investigate the distribution of the genes of two major metallo-β-1actamases (MBL;i.e.,IMP and VIM) and class 1 integrons (intI) in the clinical imipenem-resistant Pseudomonas aeruginosa, a total of 65 isolates, from a university hospital in Sichuan between December 2004 and April 2005 were screened for MBL genes by PCR using primers specific for blaIMP-1, blaVIM and blaVIM-2 genes. The MBL-positive isolates were further assessed for class 1 integrons by PCRusing specific primers. The nucleotide sequences of several PCR products were also determined. The results revealed that the blaVIM gene was found in 81.5% (53/65) of all isolates, blaVIM-2 gene was found in only 1 isolate and the intl gene was observed in 45.3% (24/53) of blaVIM-positive isolates. One isolate carried simultaneously both blaIMP-1 and intl genes, and to the best of our knowledge this is the first report of such isolate in southwest China. These observations highlight that the genes for VIM β-1actamase and class 1 integrons were predominantly present among the imipenem-resistant P. aeruginosa tested, confirming the current widespread threat of imipenem-resistant, integron-borne P.aeruginosa.展开更多
Objective:To investigate the frequency of exoU and exoY genes in patients with Pseudomonas aeruginosa infection.Methods:In this study,100 clinical isolates of Pseudomonas aeruginosa were collected from patients hospit...Objective:To investigate the frequency of exoU and exoY genes in patients with Pseudomonas aeruginosa infection.Methods:In this study,100 clinical isolates of Pseudomonas aeruginosa were collected from patients hospitalized in educational-therapeutic hospitals and were identified using standard microbiological tests.Then,the antibiotic resistance pattern of the isolates was determined by the disk agar diffusion method.The bacterial DNAs were extracted by the alkaline lysis method.Finally,the presence of exoU and exoY genes was evaluated by the PCR test.Results:In this study,47%,72%,29%,39%,40%,and 44%of the isolates were non-susceptible to piperacillin,aztreonam,ceftazidime,imipenem,tobramycin,and ciprofloxacin,respectively.In addition,95%and 93%of the clinical isolates carried the exoU and exoY genes.Blood and fecal isolates had both virulence genes,while only one wound isolate had neither genes.Meanwhile,all urinary isolates contained the exoY gene and only one isolate lacked the exoU gene.Also,88 isolates simultaneously had both exoU and exoY genes.Conclusions:High prevalence of exoU and exoY genes in this region indicates a significant role of typeⅢsecretion system in pathogenesis of Pseudomonas aeruginosa.The typeⅢsecretion system may be a suitable target to reduce the pathogenicity of this bacterium.展开更多
Background:Carbapenems are effective against severe Pseudomonas aeruginosa nosocomial infections.Therefore,carbapenem-resistant Pseudomonas aeruginosa is a serious public health threat.An understanding of the risk of ...Background:Carbapenems are effective against severe Pseudomonas aeruginosa nosocomial infections.Therefore,carbapenem-resistant Pseudomonas aeruginosa is a serious public health threat.An understanding of the risk of inappropriate exposure to different antimicrobials in resistant Pseudomonas aeruginosa infection could help in elucidating the effective approach towards using antimicrobials in vulnerable patients with CRPA infection.Object:To investigate the association between exposure ofβ-lactam antimicrobials and CRPA infection relative to control patients.Methods:The MEDLINE/PubMed and OVID/Embase databases were used to search case-control and cohort studies in English language which reported antimicrobial exposure as risk factors for CRPA infection.The pooled odds ratios(OR)were calculated using a random-effect and fixed-effect model,and forest plots from a cumulative meta-analysis method were used to better show how pooled OR changed as updated evidence accumulated.Results:A total of 24 studies comprising 7039 participants were included for cumulative meta-analysis.A positive correlation was found between development of CRPA infection and exposure of beta-lactam antimicrobials:carbapenems(OR=7.60,95%CI:3.95 to 14.62,P<0.0001),imipenem(OR=9.81,95%CI:5.56 to 17.33),ampicillin(OR=1.86,95%CI:1.14 to 2.41),piperacillin(OR=2.82,95%CI:1.46 to 2.43),penicillins(OR=1.42,95%CI:0.90 to 2.24),cephalosporins(OR=1.88,95%CI:1.46 to 2.43)andβlactamase inhibitors(OR=1.96,95%CI:1.44 to 2.67).Further,exposure of other antimicrobial agents like quinolone(OR=2.35,95%CI:1.78 to 3.10),ciprofloxacin(OR=2.35,95%CI:1.66 to 3.95),aminoglycoside(OR=2.17,95%CI:1.60 to 2.95),amikacin(OR=3.11,95%CI:2.10 to 4.61),glycopeptides(OR=3.02,95%CI:1.92 to 4.75)and vancomycin(OR=3.26,95%CI:1.48 to 7.18),were also found to be positively associated with development of CRPA infection.Conclusions:Exposure of all kinds ofβ-lactams is significantly associated with development of carbapenemresistant Pseudomonas aeruginosa infection.These findings provide an impetus to take a more active approach while usingβ-lactam antimicrobials in patients with resistant Pseudomonas aeruginosa infections.展开更多
This chemical study reports a novel siderophore-like compound,β-cyclopiazonic acid(1,β-CPA)extracted from marine fungus Aspergillus flavus.The chemical structure ofβ-CPA was elucidated by a combination of extensive...This chemical study reports a novel siderophore-like compound,β-cyclopiazonic acid(1,β-CPA)extracted from marine fungus Aspergillus flavus.The chemical structure ofβ-CPA was elucidated by a combination of extensive spectroscopic analyses and TDDFT-ECD calculations.The iron-binding ability and CAS assays demonstrate thatβ-CPA is a novel siderophore that features a different chemical structure from those of traditional siderophores.Theβ-CPA has no obvious influence on the growth of bacterium Pseudomonas aeruginosa PAO1.However,its iron chelator could promote the growth of P.aeruginosa PAO1,suggesting that P.aeruginosa employed siderophores to sequester iron,which is vital for their survival.The study provides the physiochemical evaluation ofβ-CPA,an unusual skeletonstructure siderophore,which for the first time,was proven to have the ability to bind iron and affect P.aeruginosa growth.This new discovery of siderophore provides an opportunity for developing novel anti-P.aeruginosa drugs.展开更多
BACKGROUND Pseudomonas aeruginosa(P.aeruginosa)is an important cause of nosocomial infections,and contributes to high morbidity and mortality,especially in intensive care units.P.aeruginosa is considered a'critica...BACKGROUND Pseudomonas aeruginosa(P.aeruginosa)is an important cause of nosocomial infections,and contributes to high morbidity and mortality,especially in intensive care units.P.aeruginosa is considered a'critical'category bacterial pathogen by the World Health Organization to encourage an urgent need for research and development of new antibiotics against its infections.AIM To investigate the effectiveness of baicalin combined with tobramycin therapy as a potential treatment method for carbapenem-resistant P.aeruginosa(CRPA)infections.METHODS Polymerase chain reaction(PCR)and RT-PCR were used to detect the expression levels of drug-resistant genes(including VIM,IMP and OprD2)and biofilmrelated genes(including algD,pslA and lasR)in CRPA that confer resistance to tobramycin,baicalin and tobramycin combined with baicalin(0,1/8,1/4,1/2 and 1MIC).RESULTS There was a correlation between biofilm formation and the expression of biofilmrelated genes.In addition,VIM,IMP,OprD2,algD,pslA and lasR that confer biofilm production under different concentrations in CRPA were significantly correlated.The synergistic effect of baicalin combined with tobramycin was a significant down-regulation of VIM,IMP,algD,pslA and lasR.CONCLUSION Baicalin combined with tobramycin therapy can be an effective treatment method for patients with CRPA infection.展开更多
Objective: To explore the antibacterial activity of combined use of Shuanghuanglian and cefoperazone sulbactam sodium on resistant strains of Pseudomonas aeruginosa. Methods: The Pseudomonas aeruginosa strains which w...Objective: To explore the antibacterial activity of combined use of Shuanghuanglian and cefoperazone sulbactam sodium on resistant strains of Pseudomonas aeruginosa. Methods: The Pseudomonas aeruginosa strains which were sensitive and resistant to cefoperazone sulbactam sodium were selected to prepare different test bacterial solutions respectively;The experimental liquid of Shuanghuanglian and Cefoperazone Sulbactam Sodium were prepared separately and set as different test groups and control groups;The Drug Sensitivity Tests of Shuanghuanglian and cefoperazone sulbactam sodium at different concentration gradients which were used alone or used in combination were carried out for different strains with sensitivity and resistance, And use standard entry as a reference control. Result: The results of drug sensitivity test of Shuanghuanglian combined with Cefoperazone-Sulbactam sodium against the resistant strains of Pseudomonas aeruginosa were compared with the results of drug sensitivity test of the two separately used, and the difference was statistically significant (P 〈 0.05) [The drug sensitivity test results of Shuanghuanglian and cefoperazone sulbactam sodium to Pseudomonas aeruginosa resistant strains were statistically significant compared with the drug sensitivity test results of Shuanghuanglian and Cefoperazone Sulbactam Sodium used separately (P 〈 0.05)];There was a dependence between strains and concentration in the effect of the combination of the two drugs. Conclusion: The combination of Shuanghuanglian and cefoperazone sulbactam sodium has synergistic antibacterial or bactericidal effect on Pseudomonas aeruginosa resistant strains. .展开更多
Background: Urinary Tract infections and pus are major public health problems. The evolution of bacterial resistance to antibiotics makes the treatment of these infections problematic. This is why this study is undert...Background: Urinary Tract infections and pus are major public health problems. The evolution of bacterial resistance to antibiotics makes the treatment of these infections problematic. This is why this study is undertaken to identify and evaluate the resistance of Pseudomonas aeruginosa to antibiotics. Methods: This is a prospective study carried out from December 2020 to November 2021. The germs were isolated on the agar supplemented with cetrimide and identified by the API 20 NE gallery method according to the manufacturer’s protocol. The strains’ resistance profiles were determined by the diffusion method on Mueller-Hinton according to the criteria EUCAST- 2021. Results: A total of 46/1467 (3.13%) Pseudomonas aeruginosa were identified, of which 29/1008 (2.87%) were urinary tract infections and 17/459 (3.70%) were pus. The high resistances were: 97.8% to ceftazidim, 91.3% to aztreonam, 93.5% to cefepim, 82.6% to piperacillin, 58.7% to levofloxacin, 52.2% to amikacin, 47.8% to tazobactam-piperacillin, 47.8% to tobramycin and 43.5% to ciprofloxacin. Low resistance was only 2.2% to fosfomycin, 2.2% to colistin and 15.2% to imipenem. Conclusion: This study reveals the considerable resistance of Pseudomonas aeruginosa to commonly used antibiotics, and thus compromises the empirical treatment practiced in hospitals. This result motivates the need to carry out susceptibility testing of isolates before any prescription of antimicrobials.展开更多
Objective:To establish extensively drug-resistant Pseudomonas aeruginosa(XDR-PA)infection-induced pneumonia model in rats.Methods:Twenty-four male SD rats were randomly divided into blank group,low bacterial group,med...Objective:To establish extensively drug-resistant Pseudomonas aeruginosa(XDR-PA)infection-induced pneumonia model in rats.Methods:Twenty-four male SD rats were randomly divided into blank group,low bacterial group,medium bacterial group,and high bacterial group.The low,medium and high bacterial groups were given intratracheal instillation of 0.1 mL of bacterial suspension(bacterial concentration in turn is 7.5×10^(9),3×10^(10),6×10^(10)CFU/mL),while the blank group were given the same volume of sterile normal saline.After modeling,the general conditions of rats in each group were observed,including mental state,hair,respiration,activity,eating,weight,and the survival curve was drawn.The pathological characteristics of lung tissue and the infiltration of inflammatory cells were observed.Pathogenic identification of each group was carried out by bacterial culture of lung tissue homogenate.Results:The general state of the blank group was normal,and the rats in other groups showed signs of mental depression,bristling,shortness of breath,even oral and nasal bleeding,decreased food intake and activity,and significant weight loss,and different degrees of death within 48 hours,the difference was statistically significant(P<0.05).Pathological results showed that the alveolar structure of rats in the blank group was complete,and the alveolar space was clear without exudation.The lung tissue of the low and medium bacterial groups showed obvious inflammatory cell infiltration,alveolar structure destruction,alveolar septum thickening,interstitial edema,but the pathological damage of the medium group was more severe,with a mortality rate of up to 50%,and the mortality rate of the low bacterial group was 17%.In the high bacterial group,red blood cells,inflammatory cells and a large amount of fibrin-like exudation can be seen in the alveolar space,which has the pathological characteristics of acute respiratory failure,and the mortality rate is as high as 67%.The results of bacterial culture of lung tissue homogenate showed that the blank group had no bacterial colonies,while PA colony growth can be seen in low,medium and high bacterial groups.Conclusion:9 Intratracheal instillation of low bacterial count(0.1 mL of 7.5×10^(9) CFU/mL)XDR-PA bacterial suspension can successfully construct a rat pneumonia model of XDR-PA infection.展开更多
The comparative effectiveness of remediating water polluted with crude oil, using environment-friendly bacteria (Pseudomonas aeruginosa) and fungi (Aspergillus niger) were investigated. The samples were separately tre...The comparative effectiveness of remediating water polluted with crude oil, using environment-friendly bacteria (Pseudomonas aeruginosa) and fungi (Aspergillus niger) were investigated. The samples were separately treated with Aspergillus niger and Pseudomonas aeruginosa. The bioremediation kinetic efficiency for these systems was studied. At the end of the bioremediation periods, the oil and grease content of the samples decreased from 47.0 mg/L in the untreated sample to 7.0 mg/L after 20 days when inoculated with bacteria while the sample inoculated with fungi decreased to 10.0 mg/L. Post analysis when inoculated with bacteria showed a fall in the value of the biological oxygen demand (BOD) from 73.84 mg/L to 33.28 mg/L after 20 days, while, the fungi inoculated sample showed a reduction from 73.84 mg/L to 38.48 mg/L. The biodegradation process with the bacteria was consistent with the pseudo-first-order model with a rate constant of 0.0891 day<sup>-1</sup>, while the biodegradation process with the fungi was consistent with the first order reaction model with a rate constant of 0.422 day<sup>-1</sup>. The degree of degradation after the 20<sup>th</sup> day of inoculation with Pseudomonas aeruginosa was 85.11%, while with Aspergillus niger was 78.72%. Thus, the results obtained showed that, Pseudomonas aeruginosa performed better than Aspergillus niger. The bioremediation data with fungi fitted the first-order model, while that of the bacteria fitted the pseudo-first-order model. Therefore, the data obtained in this study could be applied in the design of a bioremediation system for potential application to remediation of crude oil polluted water.展开更多
This study explores the efficacy of advanced antibiotic compounds against P. aeruginosa, focusing on Antibiotic B, an enhanced derivative of Ceftriaxone. The study measured the intracellular uptake of Antibiotic B and...This study explores the efficacy of advanced antibiotic compounds against P. aeruginosa, focusing on Antibiotic B, an enhanced derivative of Ceftriaxone. The study measured the intracellular uptake of Antibiotic B and introduced a novel adjuvant, Influximax, which augmented its antibacterial activity. Results showed a diminished potential for resistance emergence with Antibiotic B, particularly when used in combination with Influximax. The study suggests that optimizing antibiotic delivery into bacterial cells and leveraging syner-gistic adjuvant combinations can enhance drug resistance combat. .展开更多
Objective: Pseudomonas aeruginosa bloodstream infection presents a severe challenge to hospitalized patients. To investigate the clinical characteristics, risk factors and drug resistance of Pseudomonas aeruginosa blo...Objective: Pseudomonas aeruginosa bloodstream infection presents a severe challenge to hospitalized patients. To investigate the clinical characteristics, risk factors and drug resistance of Pseudomonas aeruginosa bloodstream infection. Methods: Clinical data and laboratory results of patients with Pseudomonas aeruginosa bloodstream infection in the First Affiliated Hospital of Yangtze University from January 2019 to December 2022 were retrospectively analyzed. The factors associated with infection and death were analyzed by univariate analysis. Results: A total of 55 patients were enrolled in this study, The 28-day mortality rate was 14.5%. Univariate analysis showed that high procalcitonin, low albumin, ICU admission, central venous catheterization, indwelling catheter, and mechanical ventilation were associated with death. Multivariate Logistic regression analysis showed that hypoproteinemia and central venous catheters were independent risk factors for death in patients with Pseudomonas aeruginosa bloodstream infection. Conclusions: The drug resistance of P. aeruginosa bloodstream infection is not high, but the fatality rate is high. The combination of hypoalbuminemia after the onset of the disease and the use of central vein catheters can lead to increased mortality, suggesting that clinical identification of high-risk patients as early as possible, reducing the use of catheters, preventing the occurrence of P. aeruginosa bloodstream infection and improving the prognosis.展开更多
基金a grant from National Natu-ral Science Foundation of China (No. 30370079)
文摘To investigate the distribution of the genes of two major metallo-β-1actamases (MBL;i.e.,IMP and VIM) and class 1 integrons (intI) in the clinical imipenem-resistant Pseudomonas aeruginosa, a total of 65 isolates, from a university hospital in Sichuan between December 2004 and April 2005 were screened for MBL genes by PCR using primers specific for blaIMP-1, blaVIM and blaVIM-2 genes. The MBL-positive isolates were further assessed for class 1 integrons by PCRusing specific primers. The nucleotide sequences of several PCR products were also determined. The results revealed that the blaVIM gene was found in 81.5% (53/65) of all isolates, blaVIM-2 gene was found in only 1 isolate and the intl gene was observed in 45.3% (24/53) of blaVIM-positive isolates. One isolate carried simultaneously both blaIMP-1 and intl genes, and to the best of our knowledge this is the first report of such isolate in southwest China. These observations highlight that the genes for VIM β-1actamase and class 1 integrons were predominantly present among the imipenem-resistant P. aeruginosa tested, confirming the current widespread threat of imipenem-resistant, integron-borne P.aeruginosa.
文摘Objective:To investigate the frequency of exoU and exoY genes in patients with Pseudomonas aeruginosa infection.Methods:In this study,100 clinical isolates of Pseudomonas aeruginosa were collected from patients hospitalized in educational-therapeutic hospitals and were identified using standard microbiological tests.Then,the antibiotic resistance pattern of the isolates was determined by the disk agar diffusion method.The bacterial DNAs were extracted by the alkaline lysis method.Finally,the presence of exoU and exoY genes was evaluated by the PCR test.Results:In this study,47%,72%,29%,39%,40%,and 44%of the isolates were non-susceptible to piperacillin,aztreonam,ceftazidime,imipenem,tobramycin,and ciprofloxacin,respectively.In addition,95%and 93%of the clinical isolates carried the exoU and exoY genes.Blood and fecal isolates had both virulence genes,while only one wound isolate had neither genes.Meanwhile,all urinary isolates contained the exoY gene and only one isolate lacked the exoU gene.Also,88 isolates simultaneously had both exoU and exoY genes.Conclusions:High prevalence of exoU and exoY genes in this region indicates a significant role of typeⅢsecretion system in pathogenesis of Pseudomonas aeruginosa.The typeⅢsecretion system may be a suitable target to reduce the pathogenicity of this bacterium.
文摘Background:Carbapenems are effective against severe Pseudomonas aeruginosa nosocomial infections.Therefore,carbapenem-resistant Pseudomonas aeruginosa is a serious public health threat.An understanding of the risk of inappropriate exposure to different antimicrobials in resistant Pseudomonas aeruginosa infection could help in elucidating the effective approach towards using antimicrobials in vulnerable patients with CRPA infection.Object:To investigate the association between exposure ofβ-lactam antimicrobials and CRPA infection relative to control patients.Methods:The MEDLINE/PubMed and OVID/Embase databases were used to search case-control and cohort studies in English language which reported antimicrobial exposure as risk factors for CRPA infection.The pooled odds ratios(OR)were calculated using a random-effect and fixed-effect model,and forest plots from a cumulative meta-analysis method were used to better show how pooled OR changed as updated evidence accumulated.Results:A total of 24 studies comprising 7039 participants were included for cumulative meta-analysis.A positive correlation was found between development of CRPA infection and exposure of beta-lactam antimicrobials:carbapenems(OR=7.60,95%CI:3.95 to 14.62,P<0.0001),imipenem(OR=9.81,95%CI:5.56 to 17.33),ampicillin(OR=1.86,95%CI:1.14 to 2.41),piperacillin(OR=2.82,95%CI:1.46 to 2.43),penicillins(OR=1.42,95%CI:0.90 to 2.24),cephalosporins(OR=1.88,95%CI:1.46 to 2.43)andβlactamase inhibitors(OR=1.96,95%CI:1.44 to 2.67).Further,exposure of other antimicrobial agents like quinolone(OR=2.35,95%CI:1.78 to 3.10),ciprofloxacin(OR=2.35,95%CI:1.66 to 3.95),aminoglycoside(OR=2.17,95%CI:1.60 to 2.95),amikacin(OR=3.11,95%CI:2.10 to 4.61),glycopeptides(OR=3.02,95%CI:1.92 to 4.75)and vancomycin(OR=3.26,95%CI:1.48 to 7.18),were also found to be positively associated with development of CRPA infection.Conclusions:Exposure of all kinds ofβ-lactams is significantly associated with development of carbapenemresistant Pseudomonas aeruginosa infection.These findings provide an impetus to take a more active approach while usingβ-lactam antimicrobials in patients with resistant Pseudomonas aeruginosa infections.
基金Supported by the Natural Foundation of Zhejiang Province(No.LGF21H300003)the Key Laboratory of Tropical Marine Ecosystem and Bioresource,Ministry of Natural Resources(No.2021QN03)+2 种基金the Key Research and Development Program of Zhejiang Province(No.2021C03084)the Key Research and Development Program of National Key R&D Program of China(Nos.2018YFC0311003,2017YFE0103100)the High Level Talent Special Support Plan of Zhejiang Province(No.2019R52009).We also gratefully acknowledge platform support from Zhejiang International Sci-Tech Cooperation Base for the Exploitation and Utilization of Nature Product。
文摘This chemical study reports a novel siderophore-like compound,β-cyclopiazonic acid(1,β-CPA)extracted from marine fungus Aspergillus flavus.The chemical structure ofβ-CPA was elucidated by a combination of extensive spectroscopic analyses and TDDFT-ECD calculations.The iron-binding ability and CAS assays demonstrate thatβ-CPA is a novel siderophore that features a different chemical structure from those of traditional siderophores.Theβ-CPA has no obvious influence on the growth of bacterium Pseudomonas aeruginosa PAO1.However,its iron chelator could promote the growth of P.aeruginosa PAO1,suggesting that P.aeruginosa employed siderophores to sequester iron,which is vital for their survival.The study provides the physiochemical evaluation ofβ-CPA,an unusual skeletonstructure siderophore,which for the first time,was proven to have the ability to bind iron and affect P.aeruginosa growth.This new discovery of siderophore provides an opportunity for developing novel anti-P.aeruginosa drugs.
基金Supported by Jiaxing Science and Technology Planning Project,No.2019AY32006 and No.2020AY30004。
文摘BACKGROUND Pseudomonas aeruginosa(P.aeruginosa)is an important cause of nosocomial infections,and contributes to high morbidity and mortality,especially in intensive care units.P.aeruginosa is considered a'critical'category bacterial pathogen by the World Health Organization to encourage an urgent need for research and development of new antibiotics against its infections.AIM To investigate the effectiveness of baicalin combined with tobramycin therapy as a potential treatment method for carbapenem-resistant P.aeruginosa(CRPA)infections.METHODS Polymerase chain reaction(PCR)and RT-PCR were used to detect the expression levels of drug-resistant genes(including VIM,IMP and OprD2)and biofilmrelated genes(including algD,pslA and lasR)in CRPA that confer resistance to tobramycin,baicalin and tobramycin combined with baicalin(0,1/8,1/4,1/2 and 1MIC).RESULTS There was a correlation between biofilm formation and the expression of biofilmrelated genes.In addition,VIM,IMP,OprD2,algD,pslA and lasR that confer biofilm production under different concentrations in CRPA were significantly correlated.The synergistic effect of baicalin combined with tobramycin was a significant down-regulation of VIM,IMP,algD,pslA and lasR.CONCLUSION Baicalin combined with tobramycin therapy can be an effective treatment method for patients with CRPA infection.
文摘Objective: To explore the antibacterial activity of combined use of Shuanghuanglian and cefoperazone sulbactam sodium on resistant strains of Pseudomonas aeruginosa. Methods: The Pseudomonas aeruginosa strains which were sensitive and resistant to cefoperazone sulbactam sodium were selected to prepare different test bacterial solutions respectively;The experimental liquid of Shuanghuanglian and Cefoperazone Sulbactam Sodium were prepared separately and set as different test groups and control groups;The Drug Sensitivity Tests of Shuanghuanglian and cefoperazone sulbactam sodium at different concentration gradients which were used alone or used in combination were carried out for different strains with sensitivity and resistance, And use standard entry as a reference control. Result: The results of drug sensitivity test of Shuanghuanglian combined with Cefoperazone-Sulbactam sodium against the resistant strains of Pseudomonas aeruginosa were compared with the results of drug sensitivity test of the two separately used, and the difference was statistically significant (P 〈 0.05) [The drug sensitivity test results of Shuanghuanglian and cefoperazone sulbactam sodium to Pseudomonas aeruginosa resistant strains were statistically significant compared with the drug sensitivity test results of Shuanghuanglian and Cefoperazone Sulbactam Sodium used separately (P 〈 0.05)];There was a dependence between strains and concentration in the effect of the combination of the two drugs. Conclusion: The combination of Shuanghuanglian and cefoperazone sulbactam sodium has synergistic antibacterial or bactericidal effect on Pseudomonas aeruginosa resistant strains. .
文摘Background: Urinary Tract infections and pus are major public health problems. The evolution of bacterial resistance to antibiotics makes the treatment of these infections problematic. This is why this study is undertaken to identify and evaluate the resistance of Pseudomonas aeruginosa to antibiotics. Methods: This is a prospective study carried out from December 2020 to November 2021. The germs were isolated on the agar supplemented with cetrimide and identified by the API 20 NE gallery method according to the manufacturer’s protocol. The strains’ resistance profiles were determined by the diffusion method on Mueller-Hinton according to the criteria EUCAST- 2021. Results: A total of 46/1467 (3.13%) Pseudomonas aeruginosa were identified, of which 29/1008 (2.87%) were urinary tract infections and 17/459 (3.70%) were pus. The high resistances were: 97.8% to ceftazidim, 91.3% to aztreonam, 93.5% to cefepim, 82.6% to piperacillin, 58.7% to levofloxacin, 52.2% to amikacin, 47.8% to tazobactam-piperacillin, 47.8% to tobramycin and 43.5% to ciprofloxacin. Low resistance was only 2.2% to fosfomycin, 2.2% to colistin and 15.2% to imipenem. Conclusion: This study reveals the considerable resistance of Pseudomonas aeruginosa to commonly used antibiotics, and thus compromises the empirical treatment practiced in hospitals. This result motivates the need to carry out susceptibility testing of isolates before any prescription of antimicrobials.
基金Science and Technology Projects in Key Fields of Traditional Chinese Medicine in Tianjin(No.2021010)Discipline Development Fund of First Teaching Hospital of Tianjin University of Traditional Chinese Medicine(No.XKJJ201734)。
文摘Objective:To establish extensively drug-resistant Pseudomonas aeruginosa(XDR-PA)infection-induced pneumonia model in rats.Methods:Twenty-four male SD rats were randomly divided into blank group,low bacterial group,medium bacterial group,and high bacterial group.The low,medium and high bacterial groups were given intratracheal instillation of 0.1 mL of bacterial suspension(bacterial concentration in turn is 7.5×10^(9),3×10^(10),6×10^(10)CFU/mL),while the blank group were given the same volume of sterile normal saline.After modeling,the general conditions of rats in each group were observed,including mental state,hair,respiration,activity,eating,weight,and the survival curve was drawn.The pathological characteristics of lung tissue and the infiltration of inflammatory cells were observed.Pathogenic identification of each group was carried out by bacterial culture of lung tissue homogenate.Results:The general state of the blank group was normal,and the rats in other groups showed signs of mental depression,bristling,shortness of breath,even oral and nasal bleeding,decreased food intake and activity,and significant weight loss,and different degrees of death within 48 hours,the difference was statistically significant(P<0.05).Pathological results showed that the alveolar structure of rats in the blank group was complete,and the alveolar space was clear without exudation.The lung tissue of the low and medium bacterial groups showed obvious inflammatory cell infiltration,alveolar structure destruction,alveolar septum thickening,interstitial edema,but the pathological damage of the medium group was more severe,with a mortality rate of up to 50%,and the mortality rate of the low bacterial group was 17%.In the high bacterial group,red blood cells,inflammatory cells and a large amount of fibrin-like exudation can be seen in the alveolar space,which has the pathological characteristics of acute respiratory failure,and the mortality rate is as high as 67%.The results of bacterial culture of lung tissue homogenate showed that the blank group had no bacterial colonies,while PA colony growth can be seen in low,medium and high bacterial groups.Conclusion:9 Intratracheal instillation of low bacterial count(0.1 mL of 7.5×10^(9) CFU/mL)XDR-PA bacterial suspension can successfully construct a rat pneumonia model of XDR-PA infection.
文摘The comparative effectiveness of remediating water polluted with crude oil, using environment-friendly bacteria (Pseudomonas aeruginosa) and fungi (Aspergillus niger) were investigated. The samples were separately treated with Aspergillus niger and Pseudomonas aeruginosa. The bioremediation kinetic efficiency for these systems was studied. At the end of the bioremediation periods, the oil and grease content of the samples decreased from 47.0 mg/L in the untreated sample to 7.0 mg/L after 20 days when inoculated with bacteria while the sample inoculated with fungi decreased to 10.0 mg/L. Post analysis when inoculated with bacteria showed a fall in the value of the biological oxygen demand (BOD) from 73.84 mg/L to 33.28 mg/L after 20 days, while, the fungi inoculated sample showed a reduction from 73.84 mg/L to 38.48 mg/L. The biodegradation process with the bacteria was consistent with the pseudo-first-order model with a rate constant of 0.0891 day<sup>-1</sup>, while the biodegradation process with the fungi was consistent with the first order reaction model with a rate constant of 0.422 day<sup>-1</sup>. The degree of degradation after the 20<sup>th</sup> day of inoculation with Pseudomonas aeruginosa was 85.11%, while with Aspergillus niger was 78.72%. Thus, the results obtained showed that, Pseudomonas aeruginosa performed better than Aspergillus niger. The bioremediation data with fungi fitted the first-order model, while that of the bacteria fitted the pseudo-first-order model. Therefore, the data obtained in this study could be applied in the design of a bioremediation system for potential application to remediation of crude oil polluted water.
文摘This study explores the efficacy of advanced antibiotic compounds against P. aeruginosa, focusing on Antibiotic B, an enhanced derivative of Ceftriaxone. The study measured the intracellular uptake of Antibiotic B and introduced a novel adjuvant, Influximax, which augmented its antibacterial activity. Results showed a diminished potential for resistance emergence with Antibiotic B, particularly when used in combination with Influximax. The study suggests that optimizing antibiotic delivery into bacterial cells and leveraging syner-gistic adjuvant combinations can enhance drug resistance combat. .
文摘Objective: Pseudomonas aeruginosa bloodstream infection presents a severe challenge to hospitalized patients. To investigate the clinical characteristics, risk factors and drug resistance of Pseudomonas aeruginosa bloodstream infection. Methods: Clinical data and laboratory results of patients with Pseudomonas aeruginosa bloodstream infection in the First Affiliated Hospital of Yangtze University from January 2019 to December 2022 were retrospectively analyzed. The factors associated with infection and death were analyzed by univariate analysis. Results: A total of 55 patients were enrolled in this study, The 28-day mortality rate was 14.5%. Univariate analysis showed that high procalcitonin, low albumin, ICU admission, central venous catheterization, indwelling catheter, and mechanical ventilation were associated with death. Multivariate Logistic regression analysis showed that hypoproteinemia and central venous catheters were independent risk factors for death in patients with Pseudomonas aeruginosa bloodstream infection. Conclusions: The drug resistance of P. aeruginosa bloodstream infection is not high, but the fatality rate is high. The combination of hypoalbuminemia after the onset of the disease and the use of central vein catheters can lead to increased mortality, suggesting that clinical identification of high-risk patients as early as possible, reducing the use of catheters, preventing the occurrence of P. aeruginosa bloodstream infection and improving the prognosis.
文摘采用发酵-渗透汽化耦合(fermentation coupling with pervaporation,FCP)系统和分批补料式发酵系统培养Pseudomonas aeruginosa BC1制备生物表面活性剂鼠李糖脂,两轮发酵过程分别持续124 h和107 h。在FCP系统中,最大细胞吸光度OD600为1.06;生物表面活性剂OD600为0.61;鼠李糖脂最终产量为1.3 g/L,相比于分批补料式发酵系统提高38%;对比纯水的表面张力67.52 m N/m,发酵第29 h的发酵上清液表面张力为22.56 m N/m。同时,该菌的发酵上清液对液体石蜡、机油、柴油、正己烷、十六烷均有较好的乳化能力。经GC-MS结合SPME分析发现,FCP系统分离出的渗透蒸汽冷凝液中含有乙醇、戊醇等有机物。实验结果表明,相比分批补料式发酵系统,FCP系统能够分离发酵过程中产生的一部分挥发性代谢产物,减轻这些物质对细胞生长的抑制,使细胞浓度和鼠李糖脂产量都有明显提高。