BACKGROUND Achromobacter xylosoxidans is a Gram-negative opportunistic aerobe,usually causing nosocomial infections in immunocompromised patients with manifestations including bacteremia,pneumonia,and catheter-related...BACKGROUND Achromobacter xylosoxidans is a Gram-negative opportunistic aerobe,usually causing nosocomial infections in immunocompromised patients with manifestations including bacteremia,pneumonia,and catheter-related infections.However,A.xylosoxidans have not yet been reported to cause biliary system infections.CASE SUMMARY A 72-year-old woman presented to the outpatient department of our hospital with a chief complaint of jaundice.Computed tomography of her abdomen revealed the presence of a mass of approximately 2.4 cm in the hilar portion of the common hepatic duct,consistent with hilar cholangiocarcinoma.We performed endoscopic retrograde cholangiopancreatography(ERCP)to decompress the obstructed left and right intrahepatic ducts(IHDs)and placed 10 cm and 11 cm biliary stents in the left and right IHDs,respectively.However,the day after the procedure,the patient developed post-ERCP cholangitis as the length of the right IHD stent was insufficient for proper bile drainage.The blood culture of the patient tested positive for A.xylosoxidans.Management measures included the replacement of the right IHD stent(11 cm)with a longer one(12 cm)and administering culturedirected antibiotic therapy,solving the cholangitis-related complications.After the cholangitis had resolved,the patient underwent surgery for hilar cholangiocarcinoma and survived for 912 d without recurrence.CONCLUSION A.xylosoxidans-induced biliary system infections are extremely rare.Clinical awareness of physicians and endoscopists is required as this rare pathogen might cause infection after endoscopic procedures.展开更多
Based on the principle of bacterial leaching and bacterial metallurgy,a novel technology for the detoxification of chromium-containing slag by Achromobacter sp.CH-1 and chromium recovery was proposed.Strain CH-1 cell ...Based on the principle of bacterial leaching and bacterial metallurgy,a novel technology for the detoxification of chromium-containing slag by Achromobacter sp.CH-1 and chromium recovery was proposed.Strain CH-1 cell morphology before and after Cr(Ⅵ) reduction was observed with a scanning electron microscope(SEM),and the reduction product is found to adhere to terminals of CH-1 cells.Energy-dispersive X-ray(EDX) and electron paramagnetic resonance(EPR) analyses reveal that the main component of the reduction product is Cr(Ⅲ).Furthermore,small and large-scale demonstration projects reveal that Achromobacter sp.can be used to detoxify chromium-containing slag and to selectively recover chromium by using this novel technique.Chromium recovery rate increases with decreasing particle sizes of chromium-containing slag and slagheap height.Chromium recovery rates in 10 t/batch and 20 t/batch of on-site demonstration projects for chromium-containing slag detoxification are more than 90%.展开更多
Objective:To characterize two Achromobaeter xylosoxidans recovered from 2 patients diagnosed with pertussis during a Bordetella pertussis surveillance program.Methods:Nasopharyngeal swabs from 2 children under 1 year ...Objective:To characterize two Achromobaeter xylosoxidans recovered from 2 patients diagnosed with pertussis during a Bordetella pertussis surveillance program.Methods:Nasopharyngeal swabs from 2 children under 1 year of age with clinical suspicion of pertussis were analyzed by culture and PCR.Results:Two Achromobaeter xylosoxidans A8,closely related to Bordetella spp.were recovered from 2 patients diagnosed of pertussis,both carrying the ptxA gene and IS418 the pertussis toxin encoding gene.Subsequently,antibiotic susceptibility was evaluated by disk-diffusion method and by PCR.Conclusions:Although more detailed studies are needed,the present data highlight the possibility that Achromobaeter xylosoxidans.closely related Bordetella pertussis microorganisms and not covered under the vaccine umbrella,might also result in cases of whooping cough.Thereby further surveillance is necessary to determine the extension and relevance of their pathogenic role in order to discriminate their real public health implication.展开更多
BACKGROUND Achromobacter species-associated endophthalmitis is rare and may present as either acute or chronic postoperative endophthalmitis.Delayed-onset Achromobacter species endophthalmitis appearing in acute prese...BACKGROUND Achromobacter species-associated endophthalmitis is rare and may present as either acute or chronic postoperative endophthalmitis.Delayed-onset Achromobacter species endophthalmitis appearing in acute presentation that develops more than several months after cataract surgery is very rare.Intraocular lens(IOL)removal is commonly recommended to treat Achromobacter species endophthalmitis,which is based on previous studies.Here,we report the results of surgery without IOL removal when treating patients with delayed-onset postoperative Achromobacter species endophthalmitis that developed in an acute form.CASE SUMMARY Three patients visited our ophthalmology clinic due to visual impairment that began 2-3 d earlier.They had undergone cataract surgery 5-18 mo prior.Bestcorrected visual acuity of the diseased eye was between counting fingers at 30 cm to non-light perception.They showed conjunctival injection,inflammation in the anterior chamber(cell reaction 4+)and hypopyon formation.The patients were diagnosed with infectious endophthalmitis and immediately underwent pars plana vitrectomy,anterior chamber irrigation and intravitreal injection of ceftazidime and vancomycin.Before fluid infusion,a vitreous specimen was obtained. In all cases, the IOLs were not removed. Achromobacter species was detected on vitreousspecimen culture. After surgery, the vitreous opacity decreased gradually and there was littleretinal damage. At 1 mo after treatment, the best-corrected visual acuity had improved to 20/50and 20/40.CONCLUSIONDelayed onset postoperative endophthalmitis caused by Achromobacter species can appear in anacute form. All patients responded well to early vitrectomy and administration of empiricalantibiotics including ceftazidime. There was no need for IOL removal during surgery.展开更多
Removal characteristics of sulfamethazine （SMZ） by sludge and a bacterial strain using an aerobic sequence batch reactor （ASBR） were studied. Operating conditions were optimized by varying the reaction time and sl...Removal characteristics of sulfamethazine （SMZ） by sludge and a bacterial strain using an aerobic sequence batch reactor （ASBR） were studied. Operating conditions were optimized by varying the reaction time and sludge retention time （SRT）. AnAchromobacter sp. （S-3） with the ability to remove SMZ was isolated from the ASBR. The effects of different operating parameters （pH and temperature） on the biodegradation of SMZ by S-3 were determined. The results indicate that, between 0.5 and 4 hr, reaction time of the ASBR had a significant effect on the SMZ removal efficiency in the system. The SMZ removal efficiency also increased from 45% to 80% when SRT was prolonged from 5 to 25 days, although longer SRT had no impact on SMZ removal. The SMZ adsorption rate decreased with increasing temperature, which fitted Freundiich isotherm well. The removal of SMZ in the ASBR was due to the combined effects of adsorption and degradation, and degradation played a leading role.展开更多
This paper,for the first time,reports the optimization of the critical medium components for bio-surfactant production from achromobacter xylos strain GSR21 using statistical experimental design.Response surface metho...This paper,for the first time,reports the optimization of the critical medium components for bio-surfactant production from achromobacter xylos strain GSR21 using statistical experimental design.Response surface methodology(RSM)was employed to determine the optimal levels of process variables(agar powder,yeast extract,FeSO_(4)7H_(2)O,and KH_(2)PO_(4)).Central composite design(CCD)of RSM was used to study the four variables at five levels,and bio-surfactant concentration was measured as response.Regression coefficients were calculated by regression analysis,and the model equation was determined.R^(2) value for bio-surfactant(g/L)was tested to be 0.7222,indicating that the model fitted well with the experimental results.Verification of the mathematical model was conducted by performing the experiment with the predicted optimized values,and bio-surfactant yield was found to be 9.69 g/L.Validation of the predicted model was fitted 96.9%with the experimental results conducted under the optimum conditions.Agar powder and yeast extract was identified as efficient components for bio-surfactant(achromobacter xylos GSR21)production.展开更多
Azithromycin(AZM),the most commonly prescribed antibiotic in the United States,is thought to have no activity against multidrugresistant Gram-negative pathogens such as Achromobacter xylosoxidans(AX)per standard minim...Azithromycin(AZM),the most commonly prescribed antibiotic in the United States,is thought to have no activity against multidrugresistant Gram-negative pathogens such as Achromobacter xylosoxidans(AX)per standard minimum inhibitory concentration testing in cation-adjusted Mueller Hinton Broth.Here we provide the first report of AZM bactericidal activity against carbapenemresistant isolates of AX,with a multifold decrease in minimum inhibitory concentration across 12 clinical isolates when examined under physiologic testing conditions that better recapitulate the in vivo human environment.This pharmaceutical activity,evident in eukaryotic tissue culture media,is associated with enhanced AZM intracellular penetration and synergistic killing with human whole blood,serum,and neutrophils.Additionally,AZM monotherapy inhibited preformed AX biofilm growth in a dose-dependent manner together with a reduction in viable bacteria.In an illustrative case,AZM in combination with piperacillin-tazobactam exerted clear therapeutic effects in a patient with carbapenem-resistant AX mediastinitis,sternal osteomyelitis,and aortic graft infection.Our study reinforces how current antimicrobial testing practices fail to recapitulate the host environment or host-pathogen interactions and may misleadingly declare complete resistance to useful agents,adversely affecting patient outcomes.We conclude that AZM merits further exploration in the treatment of drug-resistant AX infections.Novel approaches to antimicrobial susceptibility testing that better recapitulate the host environment should be considered,especially as infections caused by multidrug-resistant Gram-negative bacterial pathogens are expanding globally with high morbidity and mortality.展开更多
采用生长曲线指导的富集培养法,从生活污水排放渠中分离筛选出高效异养硝化细菌,并对其多样性进行了分析。结果显示,从分离得到的27株异养硝化细菌中筛选出6株高效菌株Ni1-2、Ni1-8、Ni2-5、Ni2-7、Ni3-1和Ni3-4,其48 h氨氮去除率分别为...采用生长曲线指导的富集培养法,从生活污水排放渠中分离筛选出高效异养硝化细菌,并对其多样性进行了分析。结果显示,从分离得到的27株异养硝化细菌中筛选出6株高效菌株Ni1-2、Ni1-8、Ni2-5、Ni2-7、Ni3-1和Ni3-4,其48 h氨氮去除率分别为88.9%、76.6%、87.7%、93.1%、99.2%和91.4%;结合菌落形态、革兰氏染色反应、扫描电镜观察和16S r DNA序列分析,发现菌株的种类较为丰富,初步确定Ni1-2和Ni1-8为节杆菌属(Arthrobacter),Ni2-5和Ni3-1为产碱杆菌属(Alcaligenes),Ni2-7为无色杆菌属(Achromobacter),Ni3-4为芽孢杆菌属(Bacillus)。该结果可为高效异养硝化菌的分离筛选及其多样性分析提供参考。展开更多
From nodules of perennial xerophyte desert leguminous plants – Ammodendron conollyi, Astragalus villossimus, Astragalus unifoliolatus – 151 bacterial isolates have been isolated. The study of nodulation showed that ...From nodules of perennial xerophyte desert leguminous plants – Ammodendron conollyi, Astragalus villossimus, Astragalus unifoliolatus – 151 bacterial isolates have been isolated. The study of nodulation showed that AC8-1, AC11, AC21, AC1-1, AC12-1 isolates (from Ammodendron conollyi), AV1, AV8-1, AV9, AV26-1, AV36-1 isolates (from Astragalus villossimus) and AU17-1, AU30-1, AU30-2, AU20-1, AU23 isolates (from Astragalus unifoliolatus) formed an effective nitrogen-fixing symbiosis with the host plants. As a result of 16S rRNA gene study of the salt-resistant nodule bacteria it has been determined that bacteria were related to Rhizobium, Burkholderia and Achromobacter genera. The study of isolates growth has revealed that there were fast-growing and moderately-grow- ing isolates that possessed with doubling-time varying from 20 to 45 min. Their examination for antibiotic-resistance showed that the number of bacterial colonies of selected strains decreased to some extent in the presence of chloramphenicol, but in all strains the resistance to antibiotics was detected. The further investigations of resistance of the formed symbiosis to stresses (drought, salinity) showed that at 6.41% of moisture the maximal height and biomass of inoculated plants of Ammodendron conollyi were 21 cm and 2320 mg, but at 3.8% moisture the height reduced by 4 times (up to 4.5 cm) and the biomass – by 11 times (203 mg). The analogous effect was observed in Astragalus villossimus and Astragalus unifoliolatus symbiosises. The salinity equal to 100-200 mM NaCl did not affect practically on normal growth and development of desert leguminous plants symbiosis, while for Astragalus villossimus such affecting concentration comprised up to 100 mM NaCl. The light microscopy and electron microscopy of Astragalus villossimus nodule sections showed that V1 nodule bacteria strain efficiently colonized the internal space within nodules, where they were transformed into bacteroids. At 100 mM NaCl salinity concentration the colonization of nodule bacteria within nodule plant cells reduced in comparison with control nodules of plants grown in non-salted conditions.展开更多
文摘BACKGROUND Achromobacter xylosoxidans is a Gram-negative opportunistic aerobe,usually causing nosocomial infections in immunocompromised patients with manifestations including bacteremia,pneumonia,and catheter-related infections.However,A.xylosoxidans have not yet been reported to cause biliary system infections.CASE SUMMARY A 72-year-old woman presented to the outpatient department of our hospital with a chief complaint of jaundice.Computed tomography of her abdomen revealed the presence of a mass of approximately 2.4 cm in the hilar portion of the common hepatic duct,consistent with hilar cholangiocarcinoma.We performed endoscopic retrograde cholangiopancreatography(ERCP)to decompress the obstructed left and right intrahepatic ducts(IHDs)and placed 10 cm and 11 cm biliary stents in the left and right IHDs,respectively.However,the day after the procedure,the patient developed post-ERCP cholangitis as the length of the right IHD stent was insufficient for proper bile drainage.The blood culture of the patient tested positive for A.xylosoxidans.Management measures included the replacement of the right IHD stent(11 cm)with a longer one(12 cm)and administering culturedirected antibiotic therapy,solving the cholangitis-related complications.After the cholangitis had resolved,the patient underwent surgery for hilar cholangiocarcinoma and survived for 912 d without recurrence.CONCLUSION A.xylosoxidans-induced biliary system infections are extremely rare.Clinical awareness of physicians and endoscopists is required as this rare pathogen might cause infection after endoscopic procedures.
文摘Based on the principle of bacterial leaching and bacterial metallurgy,a novel technology for the detoxification of chromium-containing slag by Achromobacter sp.CH-1 and chromium recovery was proposed.Strain CH-1 cell morphology before and after Cr(Ⅵ) reduction was observed with a scanning electron microscope(SEM),and the reduction product is found to adhere to terminals of CH-1 cells.Energy-dispersive X-ray(EDX) and electron paramagnetic resonance(EPR) analyses reveal that the main component of the reduction product is Cr(Ⅲ).Furthermore,small and large-scale demonstration projects reveal that Achromobacter sp.can be used to detoxify chromium-containing slag and to selectively recover chromium by using this novel technique.Chromium recovery rate increases with decreasing particle sizes of chromium-containing slag and slagheap height.Chromium recovery rates in 10 t/batch and 20 t/batch of on-site demonstration projects for chromium-containing slag detoxification are more than 90%.
基金supported by Sanoti Aventis del Perua fellowship from the program 13.of the ISCIII(grant number:CES11/012)+1 种基金a PhD fellowship of the ISCIII(FI12/00561)a fellowship from CONCYTEC/FONDECYT
文摘Objective:To characterize two Achromobaeter xylosoxidans recovered from 2 patients diagnosed with pertussis during a Bordetella pertussis surveillance program.Methods:Nasopharyngeal swabs from 2 children under 1 year of age with clinical suspicion of pertussis were analyzed by culture and PCR.Results:Two Achromobaeter xylosoxidans A8,closely related to Bordetella spp.were recovered from 2 patients diagnosed of pertussis,both carrying the ptxA gene and IS418 the pertussis toxin encoding gene.Subsequently,antibiotic susceptibility was evaluated by disk-diffusion method and by PCR.Conclusions:Although more detailed studies are needed,the present data highlight the possibility that Achromobaeter xylosoxidans.closely related Bordetella pertussis microorganisms and not covered under the vaccine umbrella,might also result in cases of whooping cough.Thereby further surveillance is necessary to determine the extension and relevance of their pathogenic role in order to discriminate their real public health implication.
文摘BACKGROUND Achromobacter species-associated endophthalmitis is rare and may present as either acute or chronic postoperative endophthalmitis.Delayed-onset Achromobacter species endophthalmitis appearing in acute presentation that develops more than several months after cataract surgery is very rare.Intraocular lens(IOL)removal is commonly recommended to treat Achromobacter species endophthalmitis,which is based on previous studies.Here,we report the results of surgery without IOL removal when treating patients with delayed-onset postoperative Achromobacter species endophthalmitis that developed in an acute form.CASE SUMMARY Three patients visited our ophthalmology clinic due to visual impairment that began 2-3 d earlier.They had undergone cataract surgery 5-18 mo prior.Bestcorrected visual acuity of the diseased eye was between counting fingers at 30 cm to non-light perception.They showed conjunctival injection,inflammation in the anterior chamber(cell reaction 4+)and hypopyon formation.The patients were diagnosed with infectious endophthalmitis and immediately underwent pars plana vitrectomy,anterior chamber irrigation and intravitreal injection of ceftazidime and vancomycin.Before fluid infusion,a vitreous specimen was obtained. In all cases, the IOLs were not removed. Achromobacter species was detected on vitreousspecimen culture. After surgery, the vitreous opacity decreased gradually and there was littleretinal damage. At 1 mo after treatment, the best-corrected visual acuity had improved to 20/50and 20/40.CONCLUSIONDelayed onset postoperative endophthalmitis caused by Achromobacter species can appear in anacute form. All patients responded well to early vitrectomy and administration of empiricalantibiotics including ceftazidime. There was no need for IOL removal during surgery.
基金supported by the National Natural Science Foundation of China(No.21007010)the Research Fund for the Doctoral Program of Higher Education of China(No.20090075120007)+4 种基金the Shanghai Committee of Science and Technology(No.09230500200)the Fundamental Research Funds for the Central Universities(No. 2011D11309)the Joint Funds of Chinese Transportation Ministry and Hunan Province for Science and Technology Development(No.2010-353-343-290)the Knowledge Innovation Program of the Chinese Academy of Sciences (No.KZCX2-YW-Q02-02,KZCX2-YW-BR-19)the Project of Transportation Department of Hunan Province (No.200908)
文摘Removal characteristics of sulfamethazine （SMZ） by sludge and a bacterial strain using an aerobic sequence batch reactor （ASBR） were studied. Operating conditions were optimized by varying the reaction time and sludge retention time （SRT）. AnAchromobacter sp. （S-3） with the ability to remove SMZ was isolated from the ASBR. The effects of different operating parameters （pH and temperature） on the biodegradation of SMZ by S-3 were determined. The results indicate that, between 0.5 and 4 hr, reaction time of the ASBR had a significant effect on the SMZ removal efficiency in the system. The SMZ removal efficiency also increased from 45% to 80% when SRT was prolonged from 5 to 25 days, although longer SRT had no impact on SMZ removal. The SMZ adsorption rate decreased with increasing temperature, which fitted Freundiich isotherm well. The removal of SMZ in the ASBR was due to the combined effects of adsorption and degradation, and degradation played a leading role.
文摘This paper,for the first time,reports the optimization of the critical medium components for bio-surfactant production from achromobacter xylos strain GSR21 using statistical experimental design.Response surface methodology(RSM)was employed to determine the optimal levels of process variables(agar powder,yeast extract,FeSO_(4)7H_(2)O,and KH_(2)PO_(4)).Central composite design(CCD)of RSM was used to study the four variables at five levels,and bio-surfactant concentration was measured as response.Regression coefficients were calculated by regression analysis,and the model equation was determined.R^(2) value for bio-surfactant(g/L)was tested to be 0.7222,indicating that the model fitted well with the experimental results.Verification of the mathematical model was conducted by performing the experiment with the predicted optimized values,and bio-surfactant yield was found to be 9.69 g/L.Validation of the predicted model was fitted 96.9%with the experimental results conducted under the optimum conditions.Agar powder and yeast extract was identified as efficient components for bio-surfactant(achromobacter xylos GSR21)production.
基金supported by the National Institute of Health grants K12-HD000850(to ERU),U54-HD090259(to GS and VN),1U01AI124316-01(to MK,GS,JP,and VN),and 1KL2TR001444(to MK).
文摘Azithromycin(AZM),the most commonly prescribed antibiotic in the United States,is thought to have no activity against multidrugresistant Gram-negative pathogens such as Achromobacter xylosoxidans(AX)per standard minimum inhibitory concentration testing in cation-adjusted Mueller Hinton Broth.Here we provide the first report of AZM bactericidal activity against carbapenemresistant isolates of AX,with a multifold decrease in minimum inhibitory concentration across 12 clinical isolates when examined under physiologic testing conditions that better recapitulate the in vivo human environment.This pharmaceutical activity,evident in eukaryotic tissue culture media,is associated with enhanced AZM intracellular penetration and synergistic killing with human whole blood,serum,and neutrophils.Additionally,AZM monotherapy inhibited preformed AX biofilm growth in a dose-dependent manner together with a reduction in viable bacteria.In an illustrative case,AZM in combination with piperacillin-tazobactam exerted clear therapeutic effects in a patient with carbapenem-resistant AX mediastinitis,sternal osteomyelitis,and aortic graft infection.Our study reinforces how current antimicrobial testing practices fail to recapitulate the host environment or host-pathogen interactions and may misleadingly declare complete resistance to useful agents,adversely affecting patient outcomes.We conclude that AZM merits further exploration in the treatment of drug-resistant AX infections.Novel approaches to antimicrobial susceptibility testing that better recapitulate the host environment should be considered,especially as infections caused by multidrug-resistant Gram-negative bacterial pathogens are expanding globally with high morbidity and mortality.
文摘采用生长曲线指导的富集培养法,从生活污水排放渠中分离筛选出高效异养硝化细菌,并对其多样性进行了分析。结果显示,从分离得到的27株异养硝化细菌中筛选出6株高效菌株Ni1-2、Ni1-8、Ni2-5、Ni2-7、Ni3-1和Ni3-4,其48 h氨氮去除率分别为88.9%、76.6%、87.7%、93.1%、99.2%和91.4%;结合菌落形态、革兰氏染色反应、扫描电镜观察和16S r DNA序列分析,发现菌株的种类较为丰富,初步确定Ni1-2和Ni1-8为节杆菌属(Arthrobacter),Ni2-5和Ni3-1为产碱杆菌属(Alcaligenes),Ni2-7为无色杆菌属(Achromobacter),Ni3-4为芽孢杆菌属(Bacillus)。该结果可为高效异养硝化菌的分离筛选及其多样性分析提供参考。
文摘From nodules of perennial xerophyte desert leguminous plants – Ammodendron conollyi, Astragalus villossimus, Astragalus unifoliolatus – 151 bacterial isolates have been isolated. The study of nodulation showed that AC8-1, AC11, AC21, AC1-1, AC12-1 isolates (from Ammodendron conollyi), AV1, AV8-1, AV9, AV26-1, AV36-1 isolates (from Astragalus villossimus) and AU17-1, AU30-1, AU30-2, AU20-1, AU23 isolates (from Astragalus unifoliolatus) formed an effective nitrogen-fixing symbiosis with the host plants. As a result of 16S rRNA gene study of the salt-resistant nodule bacteria it has been determined that bacteria were related to Rhizobium, Burkholderia and Achromobacter genera. The study of isolates growth has revealed that there were fast-growing and moderately-grow- ing isolates that possessed with doubling-time varying from 20 to 45 min. Their examination for antibiotic-resistance showed that the number of bacterial colonies of selected strains decreased to some extent in the presence of chloramphenicol, but in all strains the resistance to antibiotics was detected. The further investigations of resistance of the formed symbiosis to stresses (drought, salinity) showed that at 6.41% of moisture the maximal height and biomass of inoculated plants of Ammodendron conollyi were 21 cm and 2320 mg, but at 3.8% moisture the height reduced by 4 times (up to 4.5 cm) and the biomass – by 11 times (203 mg). The analogous effect was observed in Astragalus villossimus and Astragalus unifoliolatus symbiosises. The salinity equal to 100-200 mM NaCl did not affect practically on normal growth and development of desert leguminous plants symbiosis, while for Astragalus villossimus such affecting concentration comprised up to 100 mM NaCl. The light microscopy and electron microscopy of Astragalus villossimus nodule sections showed that V1 nodule bacteria strain efficiently colonized the internal space within nodules, where they were transformed into bacteroids. At 100 mM NaCl salinity concentration the colonization of nodule bacteria within nodule plant cells reduced in comparison with control nodules of plants grown in non-salted conditions.
