（＋）-cis-（1S, 2R）-Epoxypropylphosphonic acid, the enantiomer of fosfomycin, which is the industrial side-product in the preparation of the antibiotic fosfomycin, was converted into （-）fosfomycin by a seven-step ...（＋）-cis-（1S, 2R）-Epoxypropylphosphonic acid, the enantiomer of fosfomycin, which is the industrial side-product in the preparation of the antibiotic fosfomycin, was converted into （-）fosfomycin by a seven-step procedure. The esterification of the dihydroxyphosphonic intermediate was the key step. The title compound was obtained in good yield and its optical purity was up to the medicine quality standard of Chinese Pharmacopoeia.展开更多
Background: Among the common morbid causes that are prevalent among all age groups, urinary tract infections top the list. In our country, most of the UTI patients visiting hospitals (OPD or IPD) are already on empiri...Background: Among the common morbid causes that are prevalent among all age groups, urinary tract infections top the list. In our country, most of the UTI patients visiting hospitals (OPD or IPD) are already on empirical antibiotics even before getting the sensitivity report in their hand. The purpose of this research was to examine the susceptibility patterns of commonly used antibiotics, particularly fosfomycin, against common uropathogens. Methodology: This was a prospective observational study conducted between January and March 2021 in four private tertiary hospitals in Dhaka, Bangladesh. All the urine samples referred to these four laboratories, obtained from patients of all ages and both genders, clinically diagnosed to have UTI, were included. Urine culture was performed by a semiquantitative method on blood agar media and MacConkey agar media. Following identification, antimicrobial sensitivity testing was performed using the modified Kirby Bauer disk diffusion method in accordance with CLSI standards. The data was put into Statistical Package for Social Sciences (SPSS) statistical software version 25 for the analysis. Results: A total of 5389 urine samples were received from four private hospitals in Dhaka over three months, and of these, 934 (17.33%) isolates were obtained from culture. About 95% of the isolates were gram-negative bacilli (GNBs). The most common isolate was Escherichia coli 615 (65.85%), followed by Klebsiella spp. 154 (16.49%), Pseudomonas spp. 64 (6.85%) and 51 (5.46%) isolates of Enterobacter. Among the gram-positive cocci, the most common were Enterococci fecalis 18 (1.93%) and Staphylococcus aureus 17 (1.82%). Of all the antibiotics tested, fosfomycin sensitivity was 98.4%, 88.88%, and 100% for Escherichia coli, Enterococci fecalis, and Staphylococcus aureus, respectively. All the isolates tested were susceptible to Meropenem (77% - 100%), Amoxiclav (78% - 100%) and Nitrofurantoin (45% - 94%). Sensitivity amongst all the uropathogens for ceftriaxone, ciprofloxacin, and cotrimoxazole was nearly 50% - 77%. Conclusion: The positivity of urinary isolates is 17.33%, with the most common pathogen being Escherichia coli. Common uropathogens show the highest in vitro susceptibility to fosfomycin. So, fosfomycin should be considered as a highly potent and promising alternative oral antibiotic treatment for UTI.展开更多
Fosfomycin, a sodium salt ofcis-(3-methyloxiranyl) phosphonic acid, was used as electrolyte in binary methanol-water media for capillary electrophoresis. The variety of electroosmotic flow with pH*, methanol concentra...Fosfomycin, a sodium salt ofcis-(3-methyloxiranyl) phosphonic acid, was used as electrolyte in binary methanol-water media for capillary electrophoresis. The variety of electroosmotic flow with pH*, methanol concentration and ionic strength was investigated. The migration behavior of nine bases was examined under various conditions, and the separation of thymine, cytosine, 5-flurouracil, 4, 6-diamino-pyrimidine, purine was accomplished.展开更多
Fosfomycin, a broad-spectrum antibiotic against both Gram-positive and Gram-negative bacteria, is very important in the clinic but many fosfomycin-resistant bacteria have been isolated from patients. In this study, th...Fosfomycin, a broad-spectrum antibiotic against both Gram-positive and Gram-negative bacteria, is very important in the clinic but many fosfomycin-resistant bacteria have been isolated from patients. In this study, the resistance mechanism of three fosfomycin-resistant avian pathogenic Escherichia coli （APEC） strains （JE1, IF7 and CD11） isolated from septicemic chickens were analyzed. The results showed that their fosfomycin-resistance mechanisms were different. An alteration in the glpT transport system was the main reason of the fosfomycin-resistance mechanisms of strain IF7. Compared with the control stain BL21, the capacity of fosfomycin-uptake was low in all these three stains （JE 1 〉IFT〉CD 11）. Sequence results of murA showed that there were more than 10 sites of nucleotide mutation, but only one amino acid mutation T116A showed in CD11. Real-time detection test showed that the expression level of the murA gene of the three stains was significantly increased （four times increase in strain CD11 and two times increase in strains JE1 and IFT）. The transformation and recombinant test showed that the recombinant bacteria with the murA of JE1 and CD11 showed high minimal inhibitory concentration （MIC） against fosfomycin. From the results of this research, it showed that most of the fosfomycin- resistance mechanisms once showed in patient bacteria have appeared in the APEC strains and the fosfomycin-resistance mechanism of the three APEC isolates was different.展开更多
Objectives: To evaluate the efficacy, compliance, safety and economic cost for Fosfomycin trometamol and Nitofurantoin in uncomplicated lower urinary tract infections during pregnancy. Background: Nitofurantoin and Fo...Objectives: To evaluate the efficacy, compliance, safety and economic cost for Fosfomycin trometamol and Nitofurantoin in uncomplicated lower urinary tract infections during pregnancy. Background: Nitofurantoin and Fosfomycin trometamol are recommended as the first-line agents for treatment of urinary tract infections (UTIs) in the latest guidelines endorsed by the Infectious Diseases Society of America (IDSA) and the European Society for Clinical Microbiology and Infectious Diseases (ESCMID). Fosfomycin is bactericidal and inhibits bacterial cell wall biogenesis and reduces bacterial adherence to uroepithelial cells. Fosfomycin has broad antibacterial activity against both Gram-positive and Gram-negative pathogens, as Escherichia coli, Escherichia faecalis, and various Gram-negatives like Citrobacter and Proteus. Both Nitofurantoin and Fosfomycin are category B in pregnancy. Patients and Methods: This study was conducted at Tanta University Hospitals in the period from June, 1, 2015 to January, 1, 2017. Patients were recruited from outpatient clinics of Obstetrics and Gynecology and Urology Departments presenting with asymptomatic bacteruria or cystitis. Patients were allocated randomly into 2 groups: group I (n = 50 cases) received Fosfomycin therapy and group II (n = 50 cases) received Nitofurantoin therapy (n = 50 cases). After treatment, evaluation of patient symptoms, organism count, patient compliance and cost of treatment were done. Results: The enrolled patients were suffering from lower urinary tract infections;asymptomatic bacteruria (17 cases) or cystitis (83 cases). Ten patients were excluded. The demographic data of included patients were not significant for both groups. Complete relief (100%) of symptoms 5 days after start of treatment was noticed in Fosfomycin group while improvement of symptoms after 5 day-treatment was noticed in 86.49% in Nitofurantoin group (p-value = 0.030). The side effects were recorded in 7 cases (18.42%) in Fosfomycin group compared to (35.14%) with significant difference in the reported side effects, (p-value = 0.003). Compliance was 38/38 (100%) in Fosfomycin group compared to 34/37 (91.89%) in Nitrofuantoin group (p-value = 0.001). Resistance was very minimal in Fosfomycin group where 1/38 case (2.63%) reported resistance for treatment compared to 8/37 cases (21.62%) in Nitofurantoin group (p-value = 0.001). Conclusion: Fosfomycin trometamine proved to be safe, effective, and has limited resistance. Moreover higher patient compliance and fewer side effects were recommending Fosfomycin to be a first choice drug for uncomplicated lower urinary tract infections during pregnancy at Tanta University.展开更多
In recent years, heavy drug resistance in bacteria has become increasingly serious, and the progress of research and development of new antibiotics are slow. Therefore, seeking an alternative from the safe and effecti...In recent years, heavy drug resistance in bacteria has become increasingly serious, and the progress of research and development of new antibiotics are slow. Therefore, seeking an alternative from the safe and effective "old medicine" is a strategy for clinical action against infection. Among them, fosfomycin is extremely relevant. Based on the related literature at home and abroad, this review briefly introduces fosfomycin in the context of progress in synthetic methods, pharmacokinetic and pharmacodynamic characteristics, and antibacterial activities, to provide references for clinical rational use.展开更多
Treatment of hospital acquired urinary tract infections (UTIs) caused by extended-spectrum beta-Lactamases producing Klebsiella pneumonae is a major problem. This organism expresses a high level of resistance to many ...Treatment of hospital acquired urinary tract infections (UTIs) caused by extended-spectrum beta-Lactamases producing Klebsiella pneumonae is a major problem. This organism expresses a high level of resistance to many groups of antibiotics. Fosfomycin is an agent which is recommended for treatment of UTIs caused by ESBLs producers. The aim of this study is to determine the sensitivity pattern of ESBLs producing urinary K. pneumonae to antimicrobial agents including fosfomycin in patients of MUHs and determine the prevalence of fosfomycin resistance mediated by plasmid mediated fosfomycin modifying enzymes fosA, fosB and fosA3. Methods: Klebsiella pneumonae urinary isolates were collected from patients with hospital acquired UTIs in Mansoura University Hospitals (MUHs). The susceptibility pattern was determined by Kirby Baur method. Isolates resistant to extended spectrum cephalosporins were tested for ESBLs production by double disc diffusion method. Fosfomycin resistance was determined by broth dilution method. Isolates resistant to fosfomycin were tested for fosA, fosB and fosA3 by PCR. Results: A total of 128 ESBLs producing K. pneumonae isolates were collected. The highest sensitivity was to imipenem (94.5%). The lowest was to trimethoprime-sulphamethoxazole (21.8%). Co-resistance of ESBLs isolates with fosfomycin was 23.2%. Eighteen fosfomycin resistant isolates (18/30) were positive to fosA. Conclusion: ESBLs producing urinary Klebsiella pneumonae express moderate sensitivity to fosfomycin. Resistance is mainly mediated by plasmid mediated fosfomycin modifying enzymes fosA.展开更多
Background:To confirm whether baicalein improves the sensitivity of carbapenem-resistant Escherichia coli(CREC)to fosfomycin by increasing the permeability of bacterial outer membrane in vitro experiments.Methods:The ...Background:To confirm whether baicalein improves the sensitivity of carbapenem-resistant Escherichia coli(CREC)to fosfomycin by increasing the permeability of bacterial outer membrane in vitro experiments.Methods:The clinically isolated CREC strains were amplified and then divided into three groups including baicalein monotherapy groups,fosfomycin monotherapy groups,and baicalein plus fosfomycin groups,and their minimum inhibitory concentrations(MICs)measurement and interpretation were performed according to CLSI interpretive criteria.To determine bacterial permeability after contact with baicalein,CREC were incubated with fluorescein isothiocyanate(FITC)after pretreatment with blank control without baicalein,with 0.25 MIC of baicalein,and with 0.125 MIC of baicalein,followed by observation of the intrabacterial fluorescence intensity of FITC.In addition,CREC were pretreated with 0.125 MIC of baicalein and with blank control without baicalein followed by measurement of alkaline phosphatase(AKP)leak to determine the change of bacterial permeability.Results:The MIC range in baicalein monotherapy groups was from 128 mg/L to 256 mg/L,and the MIC range in fosfomycin monotherapy groups was from 16 mg/L to 1,024 mg/L,but the MIC range in both combination therapy groups was reduced to 4 mg/L to 64 mg/L.The combination use reduced the MIC of each therapy by 75%-96.88%in all strains,and the fractional inhibitory concentration index(FICI)values less than or equal to 0.5.In the permeability assay,no permeabilization of FITC was observed in the blank groups without baicalein,but the intrabacterial FITC aggregation was observed in the groups of pretreatment with 0.25 MIC of baicalein or 0.25 MIC of baicalein.In the AKP leak assay,the AKP leak was more severe at the groups of coincubation with 0.25 MIC of baicalein than those blank groups without baicalein within the first 6 hours.Conclusion:Our study suggests that baicalein may synergistically enhance the antibacterial effect of fosfomycin by increasing the permeability of CREC outer membrane.展开更多
This study was designed to find the susceptibility of Nitrofurantoin and Fosfomycin among urinary isolates of Escherichia.coli.Four hundred(400)urine samples were collected for susceptibility of nitrofurantoin and fos...This study was designed to find the susceptibility of Nitrofurantoin and Fosfomycin among urinary isolates of Escherichia.coli.Four hundred(400)urine samples were collected for susceptibility of nitrofurantoin and fosfomycin among urinary isolates of E.coli.All indoor and outdoor patients'urinary samples yielded growth of E.coli.Mid-stream urine specimens were inoculated on blood agar and CLED agar and incubated at 35±2°C.Growth was observed,and Escherichia coli was identified by Gram staining,Catalase,Motility test and API 20E(Bio murex)as per standard procedure.Antimicrobial susceptibility testing of isolates for nitrofurantoin and fosfomycin was carried out by the modified Kirby-Bauer disc diffusion method according to CLSI guidelines ATCC 25922.E.coli was used as a quality control strain.A total of 400 samples were tested susceptibility of nitrofurantoin and fosfomycin among urinary isolates of E.coli during this period.A total of 400 samples yielded the growth of E.coli,out of which 178(44.5%)were male and 222(55.5%)were female samples.Among males,18(10%)were tolerant to nitrofurantoin,and 2(1.1%)were tolerant to fosfomycin.Among females,9(4.09%)were susceptible to nitrofurantoin while 6(2.72%)were susceptible to fosfomycin.Among age groups below 45 years old,6(4.76%)were tolerant to nitrofurantoin,and 2(1.58%)were sensitive to fosfomycin.Between 46-66 years old,4(2.81%)were sensitive to nitrofurantoin,and 3(2.11%)were sensitive to fosfomycin.Between 67-90 years old,17(12.87%)were sensitive to nitrofurantoin,and 4(3.03%)were tolerant to fosfomycin.Fosfomycin and nitrofurantoin showed good susceptibility in urinary isolates of E.coli and can be used empirically in our setup.展开更多
Weaning is a challenging stage of pig farming.Animals undergo environmental,social and dietary changes leading to weaning stress syndrome.In order to compensate for the detrimental effects of weaning stress,antibiotic...Weaning is a challenging stage of pig farming.Animals undergo environmental,social and dietary changes leading to weaning stress syndrome.In order to compensate for the detrimental effects of weaning stress,antibiotics and natural extracts are used as feed additives,sometimes without fully understanding the interactions between them or even with low concentrations of mycotoxins that are frequently present in feed.The aim of this study was to evaluate the effect of fosfomycin(FOS),Cynara scolymus extract(CSE),deoxynivalenol(DON) and their combined administration on intestinal health of weaned piglets.The experiment was designed as a 2×2×2 factorial arrangement with 3 factors(FOS,CSE and DON treatments),2 levels each(presence and absence) and 3 repeats.Weaned piglets(n=24)were randomly divided in groups to receive the different treatments,namely DON administered in diet(50 μg/kg BW),FOS administered into the drinking water(30 mg/kg BW),CSE administered in diet(15 mg/kg BW) and all their combinations.After 15 d,the animals were euthanized and gastrointestinal tract samples were immediately taken to evaluate gastrointestinal pH,Enterobacteriaceae to lactic acid bacteria(E:L) ratio,volatile fatty acid(VFA) concentrations,disaccharidase(lactase,sucrase and maltase)activity,histology(intestinal absorptive area [IAA] and goblet cells count) and mucus ability to adhere pathogenic Escherichia coli.From our results,FOS and CSE treatments,individually or combined,produced a lower E:L ratio,an enhanced production of butyrate,increased disaccharidase activity(particularly maltase),and a greater IAA and goblet cells count along with an increase in pathogenic bacteria adherence to intestinal mucus.Deoxynivalenol did not show interactions with the other factors and its administration produced decreases on VFA,disaccharidase activity and goblet cells count.In conclusion,weaning piglets receiving diets containing FOS,CSE or both exhibited evident beneficial intestinal effects compared to animals receiving diets free from these compounds.On the contrary,the presence of DON at sub-toxic concentrations produced detrimental effects on intestinal health.The knowledge of the physiological and pathological gut changes produced by these compounds contributes to understand their potential productive consequences.展开更多
基金supported by R & D Special Funds for National Engineering Research Center sponsored by MOST of PR China.
文摘（＋）-cis-（1S, 2R）-Epoxypropylphosphonic acid, the enantiomer of fosfomycin, which is the industrial side-product in the preparation of the antibiotic fosfomycin, was converted into （-）fosfomycin by a seven-step procedure. The esterification of the dihydroxyphosphonic intermediate was the key step. The title compound was obtained in good yield and its optical purity was up to the medicine quality standard of Chinese Pharmacopoeia.
文摘Background: Among the common morbid causes that are prevalent among all age groups, urinary tract infections top the list. In our country, most of the UTI patients visiting hospitals (OPD or IPD) are already on empirical antibiotics even before getting the sensitivity report in their hand. The purpose of this research was to examine the susceptibility patterns of commonly used antibiotics, particularly fosfomycin, against common uropathogens. Methodology: This was a prospective observational study conducted between January and March 2021 in four private tertiary hospitals in Dhaka, Bangladesh. All the urine samples referred to these four laboratories, obtained from patients of all ages and both genders, clinically diagnosed to have UTI, were included. Urine culture was performed by a semiquantitative method on blood agar media and MacConkey agar media. Following identification, antimicrobial sensitivity testing was performed using the modified Kirby Bauer disk diffusion method in accordance with CLSI standards. The data was put into Statistical Package for Social Sciences (SPSS) statistical software version 25 for the analysis. Results: A total of 5389 urine samples were received from four private hospitals in Dhaka over three months, and of these, 934 (17.33%) isolates were obtained from culture. About 95% of the isolates were gram-negative bacilli (GNBs). The most common isolate was Escherichia coli 615 (65.85%), followed by Klebsiella spp. 154 (16.49%), Pseudomonas spp. 64 (6.85%) and 51 (5.46%) isolates of Enterobacter. Among the gram-positive cocci, the most common were Enterococci fecalis 18 (1.93%) and Staphylococcus aureus 17 (1.82%). Of all the antibiotics tested, fosfomycin sensitivity was 98.4%, 88.88%, and 100% for Escherichia coli, Enterococci fecalis, and Staphylococcus aureus, respectively. All the isolates tested were susceptible to Meropenem (77% - 100%), Amoxiclav (78% - 100%) and Nitrofurantoin (45% - 94%). Sensitivity amongst all the uropathogens for ceftriaxone, ciprofloxacin, and cotrimoxazole was nearly 50% - 77%. Conclusion: The positivity of urinary isolates is 17.33%, with the most common pathogen being Escherichia coli. Common uropathogens show the highest in vitro susceptibility to fosfomycin. So, fosfomycin should be considered as a highly potent and promising alternative oral antibiotic treatment for UTI.
基金Supported by the National Natural Science Foundation of China!(29875020)
文摘Fosfomycin, a sodium salt ofcis-(3-methyloxiranyl) phosphonic acid, was used as electrolyte in binary methanol-water media for capillary electrophoresis. The variety of electroosmotic flow with pH*, methanol concentration and ionic strength was investigated. The migration behavior of nine bases was examined under various conditions, and the separation of thymine, cytosine, 5-flurouracil, 4, 6-diamino-pyrimidine, purine was accomplished.
基金supported by the grants(30800822) from NSFCthe Innovative Research Funding of Yangzhou University, China(2011CXJ067)+1 种基金sponsored by QingLan Project,the Program for Changjiang Scholars,the Innovative Research Team in University, Ministry of Education of China(IRT0978)the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions, China(PAPD)
文摘Fosfomycin, a broad-spectrum antibiotic against both Gram-positive and Gram-negative bacteria, is very important in the clinic but many fosfomycin-resistant bacteria have been isolated from patients. In this study, the resistance mechanism of three fosfomycin-resistant avian pathogenic Escherichia coli （APEC） strains （JE1, IF7 and CD11） isolated from septicemic chickens were analyzed. The results showed that their fosfomycin-resistance mechanisms were different. An alteration in the glpT transport system was the main reason of the fosfomycin-resistance mechanisms of strain IF7. Compared with the control stain BL21, the capacity of fosfomycin-uptake was low in all these three stains （JE 1 〉IFT〉CD 11）. Sequence results of murA showed that there were more than 10 sites of nucleotide mutation, but only one amino acid mutation T116A showed in CD11. Real-time detection test showed that the expression level of the murA gene of the three stains was significantly increased （four times increase in strain CD11 and two times increase in strains JE1 and IFT）. The transformation and recombinant test showed that the recombinant bacteria with the murA of JE1 and CD11 showed high minimal inhibitory concentration （MIC） against fosfomycin. From the results of this research, it showed that most of the fosfomycin- resistance mechanisms once showed in patient bacteria have appeared in the APEC strains and the fosfomycin-resistance mechanism of the three APEC isolates was different.
文摘Objectives: To evaluate the efficacy, compliance, safety and economic cost for Fosfomycin trometamol and Nitofurantoin in uncomplicated lower urinary tract infections during pregnancy. Background: Nitofurantoin and Fosfomycin trometamol are recommended as the first-line agents for treatment of urinary tract infections (UTIs) in the latest guidelines endorsed by the Infectious Diseases Society of America (IDSA) and the European Society for Clinical Microbiology and Infectious Diseases (ESCMID). Fosfomycin is bactericidal and inhibits bacterial cell wall biogenesis and reduces bacterial adherence to uroepithelial cells. Fosfomycin has broad antibacterial activity against both Gram-positive and Gram-negative pathogens, as Escherichia coli, Escherichia faecalis, and various Gram-negatives like Citrobacter and Proteus. Both Nitofurantoin and Fosfomycin are category B in pregnancy. Patients and Methods: This study was conducted at Tanta University Hospitals in the period from June, 1, 2015 to January, 1, 2017. Patients were recruited from outpatient clinics of Obstetrics and Gynecology and Urology Departments presenting with asymptomatic bacteruria or cystitis. Patients were allocated randomly into 2 groups: group I (n = 50 cases) received Fosfomycin therapy and group II (n = 50 cases) received Nitofurantoin therapy (n = 50 cases). After treatment, evaluation of patient symptoms, organism count, patient compliance and cost of treatment were done. Results: The enrolled patients were suffering from lower urinary tract infections;asymptomatic bacteruria (17 cases) or cystitis (83 cases). Ten patients were excluded. The demographic data of included patients were not significant for both groups. Complete relief (100%) of symptoms 5 days after start of treatment was noticed in Fosfomycin group while improvement of symptoms after 5 day-treatment was noticed in 86.49% in Nitofurantoin group (p-value = 0.030). The side effects were recorded in 7 cases (18.42%) in Fosfomycin group compared to (35.14%) with significant difference in the reported side effects, (p-value = 0.003). Compliance was 38/38 (100%) in Fosfomycin group compared to 34/37 (91.89%) in Nitrofuantoin group (p-value = 0.001). Resistance was very minimal in Fosfomycin group where 1/38 case (2.63%) reported resistance for treatment compared to 8/37 cases (21.62%) in Nitofurantoin group (p-value = 0.001). Conclusion: Fosfomycin trometamine proved to be safe, effective, and has limited resistance. Moreover higher patient compliance and fewer side effects were recommending Fosfomycin to be a first choice drug for uncomplicated lower urinary tract infections during pregnancy at Tanta University.
文摘In recent years, heavy drug resistance in bacteria has become increasingly serious, and the progress of research and development of new antibiotics are slow. Therefore, seeking an alternative from the safe and effective "old medicine" is a strategy for clinical action against infection. Among them, fosfomycin is extremely relevant. Based on the related literature at home and abroad, this review briefly introduces fosfomycin in the context of progress in synthetic methods, pharmacokinetic and pharmacodynamic characteristics, and antibacterial activities, to provide references for clinical rational use.
文摘Treatment of hospital acquired urinary tract infections (UTIs) caused by extended-spectrum beta-Lactamases producing Klebsiella pneumonae is a major problem. This organism expresses a high level of resistance to many groups of antibiotics. Fosfomycin is an agent which is recommended for treatment of UTIs caused by ESBLs producers. The aim of this study is to determine the sensitivity pattern of ESBLs producing urinary K. pneumonae to antimicrobial agents including fosfomycin in patients of MUHs and determine the prevalence of fosfomycin resistance mediated by plasmid mediated fosfomycin modifying enzymes fosA, fosB and fosA3. Methods: Klebsiella pneumonae urinary isolates were collected from patients with hospital acquired UTIs in Mansoura University Hospitals (MUHs). The susceptibility pattern was determined by Kirby Baur method. Isolates resistant to extended spectrum cephalosporins were tested for ESBLs production by double disc diffusion method. Fosfomycin resistance was determined by broth dilution method. Isolates resistant to fosfomycin were tested for fosA, fosB and fosA3 by PCR. Results: A total of 128 ESBLs producing K. pneumonae isolates were collected. The highest sensitivity was to imipenem (94.5%). The lowest was to trimethoprime-sulphamethoxazole (21.8%). Co-resistance of ESBLs isolates with fosfomycin was 23.2%. Eighteen fosfomycin resistant isolates (18/30) were positive to fosA. Conclusion: ESBLs producing urinary Klebsiella pneumonae express moderate sensitivity to fosfomycin. Resistance is mainly mediated by plasmid mediated fosfomycin modifying enzymes fosA.
基金This work was supported by Wenling Science and Technology Bureau for Youth Scholars(No.2021S00058).
文摘Background:To confirm whether baicalein improves the sensitivity of carbapenem-resistant Escherichia coli(CREC)to fosfomycin by increasing the permeability of bacterial outer membrane in vitro experiments.Methods:The clinically isolated CREC strains were amplified and then divided into three groups including baicalein monotherapy groups,fosfomycin monotherapy groups,and baicalein plus fosfomycin groups,and their minimum inhibitory concentrations(MICs)measurement and interpretation were performed according to CLSI interpretive criteria.To determine bacterial permeability after contact with baicalein,CREC were incubated with fluorescein isothiocyanate(FITC)after pretreatment with blank control without baicalein,with 0.25 MIC of baicalein,and with 0.125 MIC of baicalein,followed by observation of the intrabacterial fluorescence intensity of FITC.In addition,CREC were pretreated with 0.125 MIC of baicalein and with blank control without baicalein followed by measurement of alkaline phosphatase(AKP)leak to determine the change of bacterial permeability.Results:The MIC range in baicalein monotherapy groups was from 128 mg/L to 256 mg/L,and the MIC range in fosfomycin monotherapy groups was from 16 mg/L to 1,024 mg/L,but the MIC range in both combination therapy groups was reduced to 4 mg/L to 64 mg/L.The combination use reduced the MIC of each therapy by 75%-96.88%in all strains,and the fractional inhibitory concentration index(FICI)values less than or equal to 0.5.In the permeability assay,no permeabilization of FITC was observed in the blank groups without baicalein,but the intrabacterial FITC aggregation was observed in the groups of pretreatment with 0.25 MIC of baicalein or 0.25 MIC of baicalein.In the AKP leak assay,the AKP leak was more severe at the groups of coincubation with 0.25 MIC of baicalein than those blank groups without baicalein within the first 6 hours.Conclusion:Our study suggests that baicalein may synergistically enhance the antibacterial effect of fosfomycin by increasing the permeability of CREC outer membrane.
文摘This study was designed to find the susceptibility of Nitrofurantoin and Fosfomycin among urinary isolates of Escherichia.coli.Four hundred(400)urine samples were collected for susceptibility of nitrofurantoin and fosfomycin among urinary isolates of E.coli.All indoor and outdoor patients'urinary samples yielded growth of E.coli.Mid-stream urine specimens were inoculated on blood agar and CLED agar and incubated at 35±2°C.Growth was observed,and Escherichia coli was identified by Gram staining,Catalase,Motility test and API 20E(Bio murex)as per standard procedure.Antimicrobial susceptibility testing of isolates for nitrofurantoin and fosfomycin was carried out by the modified Kirby-Bauer disc diffusion method according to CLSI guidelines ATCC 25922.E.coli was used as a quality control strain.A total of 400 samples were tested susceptibility of nitrofurantoin and fosfomycin among urinary isolates of E.coli during this period.A total of 400 samples yielded the growth of E.coli,out of which 178(44.5%)were male and 222(55.5%)were female samples.Among males,18(10%)were tolerant to nitrofurantoin,and 2(1.1%)were tolerant to fosfomycin.Among females,9(4.09%)were susceptible to nitrofurantoin while 6(2.72%)were susceptible to fosfomycin.Among age groups below 45 years old,6(4.76%)were tolerant to nitrofurantoin,and 2(1.58%)were sensitive to fosfomycin.Between 46-66 years old,4(2.81%)were sensitive to nitrofurantoin,and 3(2.11%)were sensitive to fosfomycin.Between 67-90 years old,17(12.87%)were sensitive to nitrofurantoin,and 4(3.03%)were tolerant to fosfomycin.Fosfomycin and nitrofurantoin showed good susceptibility in urinary isolates of E.coli and can be used empirically in our setup.
基金supported by Consejo Nacional de Investigaciones Cientificas y Tecnicas(PICT 2012-2398)from Argentina.
文摘Weaning is a challenging stage of pig farming.Animals undergo environmental,social and dietary changes leading to weaning stress syndrome.In order to compensate for the detrimental effects of weaning stress,antibiotics and natural extracts are used as feed additives,sometimes without fully understanding the interactions between them or even with low concentrations of mycotoxins that are frequently present in feed.The aim of this study was to evaluate the effect of fosfomycin(FOS),Cynara scolymus extract(CSE),deoxynivalenol(DON) and their combined administration on intestinal health of weaned piglets.The experiment was designed as a 2×2×2 factorial arrangement with 3 factors(FOS,CSE and DON treatments),2 levels each(presence and absence) and 3 repeats.Weaned piglets(n=24)were randomly divided in groups to receive the different treatments,namely DON administered in diet(50 μg/kg BW),FOS administered into the drinking water(30 mg/kg BW),CSE administered in diet(15 mg/kg BW) and all their combinations.After 15 d,the animals were euthanized and gastrointestinal tract samples were immediately taken to evaluate gastrointestinal pH,Enterobacteriaceae to lactic acid bacteria(E:L) ratio,volatile fatty acid(VFA) concentrations,disaccharidase(lactase,sucrase and maltase)activity,histology(intestinal absorptive area [IAA] and goblet cells count) and mucus ability to adhere pathogenic Escherichia coli.From our results,FOS and CSE treatments,individually or combined,produced a lower E:L ratio,an enhanced production of butyrate,increased disaccharidase activity(particularly maltase),and a greater IAA and goblet cells count along with an increase in pathogenic bacteria adherence to intestinal mucus.Deoxynivalenol did not show interactions with the other factors and its administration produced decreases on VFA,disaccharidase activity and goblet cells count.In conclusion,weaning piglets receiving diets containing FOS,CSE or both exhibited evident beneficial intestinal effects compared to animals receiving diets free from these compounds.On the contrary,the presence of DON at sub-toxic concentrations produced detrimental effects on intestinal health.The knowledge of the physiological and pathological gut changes produced by these compounds contributes to understand their potential productive consequences.
