Background Mastitis is an inflammatory disease of the mammary gland that has serious economic impacts on the dairy industry and endangers food safety.Our previous study found that the body has a gut/rumen-mammary glan...Background Mastitis is an inflammatory disease of the mammary gland that has serious economic impacts on the dairy industry and endangers food safety.Our previous study found that the body has a gut/rumen-mammary gland axis and that disturbance of the gut/rumen microbiota could result in‘gastroenterogenic mastitis'.However,the mechanism has not been fully clarified.Recently,we found that long-term feeding of a high-concentrate diet induced mastitis in dairy cows,and the abundance of Stenotrophomonas maltophilia(S.maltophilia)was significantly increased in both the rumen and milk microbiota.Accordingly,we hypothesized that‘gastroenterogenic mastitis'can be induced by the migration of endogenous gut bacteria to the mammary gland.Therefore,this study investigated the mechanism by which enterogenic S.maltophilia induces mastitis.Results First,S.maltophilia was labelled with superfolder GFP and administered to mice via gavage.The results showed that treatment with S.maltophilia promoted the occurrence of mastitis and increased the permeability of the blood-milk barrier,leading to intestinal inflammation and intestinal leakage.Furthermore,tracking of ingested S.maltophilia revealed that S.maltophilia could migrate from the gut to the mammary gland and induce mastitis.Subsequently,mammary gland transcriptome analysis showed that the calcium and AMPK signalling pathways were significantly upregulated in mice treated with S.maltophilia.Then,using mouse mammary epithelial cells(MMECs),we verified that S.maltophilia induces mastitis through activation of the calcium-ROS-AMPK-mTOR-autophagy pathway.Conclusions In conclusion,the results showed that enterogenic S.maltophilia could migrate from the gut to the mammary gland via the gut-mammary axis and activate the calcium-ROS-AMPK-mTOR-autophagy pathway to induce mastitis.Targeting the gut-mammary gland axis may also be an effective method to treat mastitis.展开更多
Objectives: To investigate possible sources of Stenotrophomonas maltophilia(S. maltophilia) in the clinical environment.Methods: Different samples were collected from Amol City of Iran. Steps for the identification of...Objectives: To investigate possible sources of Stenotrophomonas maltophilia(S. maltophilia) in the clinical environment.Methods: Different samples were collected from Amol City of Iran. Steps for the identification of S. maltophilia included culturing, biochemical tests, polymerase chain reaction(PCR) of 16 S r RNA gene and 23 S r RNA gene. In addition, production of melanin pigment and patterns of motility of the bacteria, were also investigated.Results: In our study, 20 S. maltophilia strains were isolated from clinical sources,oxygen manometer apparatus of hospitals were 7/110(6.36%), blood was 1/777(0.13%),sputum was 4/40(4%), urine was 1/2 947(0.03%), tap water was 1/240(0.42%) and dental suction was 6/120(5%). The isolated bacteria showed production of melanin pigment with rates of strong, moderate, weak, and lack of pigment. Types of motilities were seen in isolates.Conclusions: The highest percentage of bacteria is isolated of oxygen manometer system and dental suction, yet has not been reported from oxygen manometer system. These bacteria have also been associated with patients who have respiratory problems, so it is essential for staffs of hospitals to draw attention to this source of bacteria.展开更多
The phosphate solubilizing characteristics of a strain YC, which was isolated from phosphate mines (Hubei, China), were studied in National Botanical Research Institute’s phosphate (NBRIP) growth medium containing tr...The phosphate solubilizing characteristics of a strain YC, which was isolated from phosphate mines (Hubei, China), were studied in National Botanical Research Institute’s phosphate (NBRIP) growth medium containing tricalcium phosphate (TCP) as sole phosphorus (P) source. The strain YC is identified as Stenotrophomonas maltophilia (S. maltophilia) based upon the results of morphologic, physiological and biochemical characteristics and 16S rRNA sequences analysis. The results show that the strain S. maltophilia YC can solubilize TCP and release soluble P in NBRIP growth medium. A positive correlation between concentration of soluble P and population of the isolate and a negative correlation between concentration of soluble P and pH in the culture medium are observed from statistical analysis results. Moreover, gluconic acid is detected in the culture medium by HPLC analysis. It indicates that the isolate can release gluconic acid during the solubilizing experiment, which causes acidification of the culture medium and then TCP solubilization. S. maltophilia YC has a maximal TCP solubilizing capability when using maltose as carbon source and ammonium nitrate as nitrogen source, respectively, in NBRIP growth medium.展开更多
The ability of Stenotrophomonas maltophilia was demonstrated to selectively remove Cu2+from Cu(NO3)2 solution under the circumstance that 1 mg/L benzo[a]pyrene(BaP) was either present or not. The removal ratios of 2 a...The ability of Stenotrophomonas maltophilia was demonstrated to selectively remove Cu2+from Cu(NO3)2 solution under the circumstance that 1 mg/L benzo[a]pyrene(BaP) was either present or not. The removal ratios of 2 and 10 mg/L Cu2+by 0.25 g/L biosorbent are up to 80% and 49% at 10 min, respectively. The biosorption includes ion exchange, NO3 reduction, ion release, and cell oxidation by Cu2+. BaP does not significantly affect Cu2+removal and ion release. Although 2 mg/L Cu2+increases the release of PO4 3, K+, NH4 +and Ca2+, 10 mg/L Cu2+has strong oxidation on cell, and then decreases NO3 reduction and hinders the release of K+, NH4 +and Ca2+. Exogenous cations inhibit the Cu2+biosorption, while additional anions increase the removal ratios of 10 mg/L Cu2+from 52% to 88%.展开更多
BACKGROUND Stenotrophomonas maltophilia(S.maltophilia)is a rare cause of neonatal sepsis with significant morbidity and mortality and has extensive resistance to several antibiotics leaving few options for antimicrobi...BACKGROUND Stenotrophomonas maltophilia(S.maltophilia)is a rare cause of neonatal sepsis with significant morbidity and mortality and has extensive resistance to several antibiotics leaving few options for antimicrobial therapy.Only a few cases have been reported in neonates from developing countries.We report three cases of critically ill,extramural babies with neonatal S.maltophilia sepsis.All three babies recovered and were discharged.CASE SUMMARY All three cases were term extramural babies,who were critically ill at the time of presentation at our neonatal intensive care unit.They had features of multiorgan dysfunction at admission.Blood culture was positive for S.maltophilia in two babies and one had a positive tracheal aspirate culture.The babies were treated according to the antibiogram available.They recovered and were subsequently discharged.CONCLUSION Although various authors have reported S.maltophilia in pediatric and adult populations,only a few cases have been reported in the newborn period and this infection is even rarer in developing countries.Although S.maltophilia infection has a grave outcome,our three babies were successfully treated and subsequently discharged.展开更多
We present a case of keratitis caused by Stenotrophomonas maltophilia in a therapeutic contact lens user with trichiasis and symblepharon. This keratitis was initially diagnosed as caused by Achromobacter xylosoxidans...We present a case of keratitis caused by Stenotrophomonas maltophilia in a therapeutic contact lens user with trichiasis and symblepharon. This keratitis was initially diagnosed as caused by Achromobacter xylosoxidans, but the strain was sent for species confirmation and the isolate was finally identified as S. maltophilia by means of 16S rDNA sequencing. The patient rapidly improved on administration of fortified ceftazidime. Physicians should be aware that the definitive identification of the pathogenic agent and prolonged antimicrobial treatment according to culture sensitivities in keratitis are mandatory as treatment success depends greatly on them.展开更多
Objectives: To determine the mutant prevention concentration (MPC) of sulfamethoxazole-trimethoprim (SXT) alone and in combination with levofloxacin (LVX) against Stenotrophomonas maltophilia (S. maltophilia) and to d...Objectives: To determine the mutant prevention concentration (MPC) of sulfamethoxazole-trimethoprim (SXT) alone and in combination with levofloxacin (LVX) against Stenotrophomonas maltophilia (S. maltophilia) and to determine if the combination may decrease the emergence of resistant mutants. Methods: The MPC with 20 S. maltophilia strains which were both susceptible to SXT and LVX were determined by inhibiting visible growth among 1010 CFU on four agar plates after 72 hours incubation at 37°C. Results: All except two strains (18/20) showed a mutant prevention concentration ≥ 152/8 μg/mL for SXT and the range of the mutant prevention concentration for the SXT in combination with LVX is 9.5/0.5~608/32 μg/mL, which demonstrates at least 2 fold reduction except one strain. There was a significant difference (P < 0.01) between SXT alone and in combination with LVX on the mutant prevention concentration and mutant prevention concentration/minimum inhibitory concentration values. Conclusions: The MPC/MIC values were narrowed for SXT by combining with LVX against the S maltophilia. The combination may decrease the enrichment of mutant bacterial populations. Much study is needed to verify whether the using of drug combinations may restrict or even block the selection of S. maltophilia mutants.展开更多
Poultry industry produces a vast amount of feather waste annually, which forms a burden for environment protection.However, feathers are valuable bio-resources with high keratinaceous protein content and can be conver...Poultry industry produces a vast amount of feather waste annually, which forms a burden for environment protection.However, feathers are valuable bio-resources with high keratinaceous protein content and can be converted into more valuable materials through some approaches such as biodegradation by microorganism-derived keratinases. The characters of keratinases in microorganisms remain largely undetermined. In this study,it is reported that the morphological change of cell surface and the activities of intracellular and extracellular keratinases in Stenotrophomonas maltophilia( S. maltophilia) DHHJ. S. maltophilia DHHJ was cultured on lysogeny broth( LB) and feather broth(FB) through fermenter technology,and ultrastructure of cell and keratinase activity including extracellular and intracellular enzyme were observed respectively. Ultrastructural change on the cell surface was only observed for the bacteria cultured on FB medium,but not on LB,suggesting that the change could be induced by feather keratin. Therefore, the results showed that extracellular keratinase is a kind of induction enzyme while intracellular keratinase is a kind of constitute enzyme in S. maltophilia DHHJ.展开更多
The paper was to find the bacteria to degrade aflatoxin B 1 （AFB 1） and realize the application of biological degradation on AFB 1. Using cumarin as the carbon source and energy on the first screening, then the ten ...The paper was to find the bacteria to degrade aflatoxin B 1 （AFB 1） and realize the application of biological degradation on AFB 1. Using cumarin as the carbon source and energy on the first screening, then the ten strains which were first screened out were taken to degrade AFB 1 100 pg kg^-1. Strain NMO-3 was screened out of ten strains, the degradation ratio of AFB 1 reached 85.7%, which was more prominent than the others （P 〈 0.01）. With the analysis of colony morphology, physiological and biochemistry experiments, and 16S rDNA gene sequence, the strain NMO-3 was finally identified as Stenotrophomonas sp. Using cumarin as the carbon source and energy could screen out the AFB 1 degradation strains. Acute toxicity tests show that the viable number of NMO-3 lower than 3.12 × 10^10 cfu mL-1 is safety. The crude enzyme was obtained by 65% ammonium sulfate fractionation, and it could degrade AFB1. It is the first report for the strain＇s detoxi- AFB1.展开更多
基金supported by the National Natural Science Foundation of China(32102738,32122087,and 31972749)Scientific research project of Education Department of Jilin Province(No.JJKH20251201KJ)。
文摘Background Mastitis is an inflammatory disease of the mammary gland that has serious economic impacts on the dairy industry and endangers food safety.Our previous study found that the body has a gut/rumen-mammary gland axis and that disturbance of the gut/rumen microbiota could result in‘gastroenterogenic mastitis'.However,the mechanism has not been fully clarified.Recently,we found that long-term feeding of a high-concentrate diet induced mastitis in dairy cows,and the abundance of Stenotrophomonas maltophilia(S.maltophilia)was significantly increased in both the rumen and milk microbiota.Accordingly,we hypothesized that‘gastroenterogenic mastitis'can be induced by the migration of endogenous gut bacteria to the mammary gland.Therefore,this study investigated the mechanism by which enterogenic S.maltophilia induces mastitis.Results First,S.maltophilia was labelled with superfolder GFP and administered to mice via gavage.The results showed that treatment with S.maltophilia promoted the occurrence of mastitis and increased the permeability of the blood-milk barrier,leading to intestinal inflammation and intestinal leakage.Furthermore,tracking of ingested S.maltophilia revealed that S.maltophilia could migrate from the gut to the mammary gland and induce mastitis.Subsequently,mammary gland transcriptome analysis showed that the calcium and AMPK signalling pathways were significantly upregulated in mice treated with S.maltophilia.Then,using mouse mammary epithelial cells(MMECs),we verified that S.maltophilia induces mastitis through activation of the calcium-ROS-AMPK-mTOR-autophagy pathway.Conclusions In conclusion,the results showed that enterogenic S.maltophilia could migrate from the gut to the mammary gland via the gut-mammary axis and activate the calcium-ROS-AMPK-mTOR-autophagy pathway to induce mastitis.Targeting the gut-mammary gland axis may also be an effective method to treat mastitis.
基金funded by Islamic Azad University Karaj Branch (grant number: 1193)
文摘Objectives: To investigate possible sources of Stenotrophomonas maltophilia(S. maltophilia) in the clinical environment.Methods: Different samples were collected from Amol City of Iran. Steps for the identification of S. maltophilia included culturing, biochemical tests, polymerase chain reaction(PCR) of 16 S r RNA gene and 23 S r RNA gene. In addition, production of melanin pigment and patterns of motility of the bacteria, were also investigated.Results: In our study, 20 S. maltophilia strains were isolated from clinical sources,oxygen manometer apparatus of hospitals were 7/110(6.36%), blood was 1/777(0.13%),sputum was 4/40(4%), urine was 1/2 947(0.03%), tap water was 1/240(0.42%) and dental suction was 6/120(5%). The isolated bacteria showed production of melanin pigment with rates of strong, moderate, weak, and lack of pigment. Types of motilities were seen in isolates.Conclusions: The highest percentage of bacteria is isolated of oxygen manometer system and dental suction, yet has not been reported from oxygen manometer system. These bacteria have also been associated with patients who have respiratory problems, so it is essential for staffs of hospitals to draw attention to this source of bacteria.
基金Project(2004CB619201) supported by the Major State Basic Research and Development Program of ChinaProject(Z200515002) supported by the Key Project Foundation of the Education Department of Hubei Province, China+1 种基金Project(GCP200801) supported by the Open Research Fund of Key Laboratory for Green Chemical Process of Ministry of Education, ChinaProject(Q200811) supported by the Youths Science Foundation of Wuhan Institute of Technology, China
文摘The phosphate solubilizing characteristics of a strain YC, which was isolated from phosphate mines (Hubei, China), were studied in National Botanical Research Institute’s phosphate (NBRIP) growth medium containing tricalcium phosphate (TCP) as sole phosphorus (P) source. The strain YC is identified as Stenotrophomonas maltophilia (S. maltophilia) based upon the results of morphologic, physiological and biochemical characteristics and 16S rRNA sequences analysis. The results show that the strain S. maltophilia YC can solubilize TCP and release soluble P in NBRIP growth medium. A positive correlation between concentration of soluble P and population of the isolate and a negative correlation between concentration of soluble P and pH in the culture medium are observed from statistical analysis results. Moreover, gluconic acid is detected in the culture medium by HPLC analysis. It indicates that the isolate can release gluconic acid during the solubilizing experiment, which causes acidification of the culture medium and then TCP solubilization. S. maltophilia YC has a maximal TCP solubilizing capability when using maltose as carbon source and ammonium nitrate as nitrogen source, respectively, in NBRIP growth medium.
基金Projects(21007020,U0933002,U0833002) supported by the National Natural Science Foundation of ChinaProject(2009B030500002) supported by the Science and Technology Projects of Guangdong Province,China
文摘The ability of Stenotrophomonas maltophilia was demonstrated to selectively remove Cu2+from Cu(NO3)2 solution under the circumstance that 1 mg/L benzo[a]pyrene(BaP) was either present or not. The removal ratios of 2 and 10 mg/L Cu2+by 0.25 g/L biosorbent are up to 80% and 49% at 10 min, respectively. The biosorption includes ion exchange, NO3 reduction, ion release, and cell oxidation by Cu2+. BaP does not significantly affect Cu2+removal and ion release. Although 2 mg/L Cu2+increases the release of PO4 3, K+, NH4 +and Ca2+, 10 mg/L Cu2+has strong oxidation on cell, and then decreases NO3 reduction and hinders the release of K+, NH4 +and Ca2+. Exogenous cations inhibit the Cu2+biosorption, while additional anions increase the removal ratios of 10 mg/L Cu2+from 52% to 88%.
文摘BACKGROUND Stenotrophomonas maltophilia(S.maltophilia)is a rare cause of neonatal sepsis with significant morbidity and mortality and has extensive resistance to several antibiotics leaving few options for antimicrobial therapy.Only a few cases have been reported in neonates from developing countries.We report three cases of critically ill,extramural babies with neonatal S.maltophilia sepsis.All three babies recovered and were discharged.CASE SUMMARY All three cases were term extramural babies,who were critically ill at the time of presentation at our neonatal intensive care unit.They had features of multiorgan dysfunction at admission.Blood culture was positive for S.maltophilia in two babies and one had a positive tracheal aspirate culture.The babies were treated according to the antibiogram available.They recovered and were subsequently discharged.CONCLUSION Although various authors have reported S.maltophilia in pediatric and adult populations,only a few cases have been reported in the newborn period and this infection is even rarer in developing countries.Although S.maltophilia infection has a grave outcome,our three babies were successfully treated and subsequently discharged.
文摘We present a case of keratitis caused by Stenotrophomonas maltophilia in a therapeutic contact lens user with trichiasis and symblepharon. This keratitis was initially diagnosed as caused by Achromobacter xylosoxidans, but the strain was sent for species confirmation and the isolate was finally identified as S. maltophilia by means of 16S rDNA sequencing. The patient rapidly improved on administration of fortified ceftazidime. Physicians should be aware that the definitive identification of the pathogenic agent and prolonged antimicrobial treatment according to culture sensitivities in keratitis are mandatory as treatment success depends greatly on them.
文摘Objectives: To determine the mutant prevention concentration (MPC) of sulfamethoxazole-trimethoprim (SXT) alone and in combination with levofloxacin (LVX) against Stenotrophomonas maltophilia (S. maltophilia) and to determine if the combination may decrease the emergence of resistant mutants. Methods: The MPC with 20 S. maltophilia strains which were both susceptible to SXT and LVX were determined by inhibiting visible growth among 1010 CFU on four agar plates after 72 hours incubation at 37°C. Results: All except two strains (18/20) showed a mutant prevention concentration ≥ 152/8 μg/mL for SXT and the range of the mutant prevention concentration for the SXT in combination with LVX is 9.5/0.5~608/32 μg/mL, which demonstrates at least 2 fold reduction except one strain. There was a significant difference (P < 0.01) between SXT alone and in combination with LVX on the mutant prevention concentration and mutant prevention concentration/minimum inhibitory concentration values. Conclusions: The MPC/MIC values were narrowed for SXT by combining with LVX against the S maltophilia. The combination may decrease the enrichment of mutant bacterial populations. Much study is needed to verify whether the using of drug combinations may restrict or even block the selection of S. maltophilia mutants.
基金National Natural Science Foundations of China(Nos.31000989,31570106)
文摘Poultry industry produces a vast amount of feather waste annually, which forms a burden for environment protection.However, feathers are valuable bio-resources with high keratinaceous protein content and can be converted into more valuable materials through some approaches such as biodegradation by microorganism-derived keratinases. The characters of keratinases in microorganisms remain largely undetermined. In this study,it is reported that the morphological change of cell surface and the activities of intracellular and extracellular keratinases in Stenotrophomonas maltophilia( S. maltophilia) DHHJ. S. maltophilia DHHJ was cultured on lysogeny broth( LB) and feather broth(FB) through fermenter technology,and ultrastructure of cell and keratinase activity including extracellular and intracellular enzyme were observed respectively. Ultrastructural change on the cell surface was only observed for the bacteria cultured on FB medium,but not on LB,suggesting that the change could be induced by feather keratin. Therefore, the results showed that extracellular keratinase is a kind of induction enzyme while intracellular keratinase is a kind of constitute enzyme in S. maltophilia DHHJ.
基金the Ministry of Science and Technology of China (2005DKA21204-11)the Na-tional Natural Science Foundation of China (30571353)the National High Technology Research and Devel-opment Program of China (863 Program,2006AA10Z442)
文摘The paper was to find the bacteria to degrade aflatoxin B 1 （AFB 1） and realize the application of biological degradation on AFB 1. Using cumarin as the carbon source and energy on the first screening, then the ten strains which were first screened out were taken to degrade AFB 1 100 pg kg^-1. Strain NMO-3 was screened out of ten strains, the degradation ratio of AFB 1 reached 85.7%, which was more prominent than the others （P 〈 0.01）. With the analysis of colony morphology, physiological and biochemistry experiments, and 16S rDNA gene sequence, the strain NMO-3 was finally identified as Stenotrophomonas sp. Using cumarin as the carbon source and energy could screen out the AFB 1 degradation strains. Acute toxicity tests show that the viable number of NMO-3 lower than 3.12 × 10^10 cfu mL-1 is safety. The crude enzyme was obtained by 65% ammonium sulfate fractionation, and it could degrade AFB1. It is the first report for the strain＇s detoxi- AFB1.
