scholarly journals Evaluation of the relationship between the minimum inhibitory concentration of ceftiofur and third-generation cephalosporins in Escherichia coli isolates from food-producing animals

2017 ◽  
Vol 29 (5) ◽  
pp. 716-720 ◽  
Author(s):  
Mototaka Hiki ◽  
Yasuhito Shimizu ◽  
Michiko Kawanishi ◽  
Manao Ozawa ◽  
Hitoshi Abo ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Inhibitory Concentration ◽  
Correlation Coefficients ◽  
Third Generation ◽  
Susceptibility Data ◽  
Microdilution Method ◽  
C Statistic ◽  
Broth Microdilution Method ◽  
The Relationship ◽  
Third Generation Cephalosporins

To enable future comparison of the antimicrobial susceptibility data between bacteria obtained from animals and humans, it is necessary to compare the relationships between minimum inhibitory concentrations (MICs) of veterinary and human medicine. We evaluated the relationship between the MIC of ceftiofur (CTF) and the MICs of other third-generation cephalosporins (TGCs): cefotaxime (CTX), cefpodoxime (CPDX), and ceftazidime (CAZ), determined by the broth microdilution method using 118 cefazolin-resistant Escherichia coli isolates from food-producing animals. Using the Clinical and Laboratory Standards Institute criteria, very major classification errors were observed only in CAZ (17.8%, 21 of 118); major and minor errors were observed in all TGCs (CTX: 0.8% [1 of 118] and 9.3% [11 of 118]; CPDX: 9.3% [11 of 118] and 6.8% [8 of 118]; CAZ: 2.5% [3 of 118] and 9.3% [11 of 118], respectively). The Spearman correlation coefficients between the MICs of CTF and CTX, CPDX, and CAZ were 0.765, 0.731, and 0.306, respectively. The sensitivity and specificity values were 100.0% and 81.8% for CTX, 99.0% and 27.3% for CPDX, and 76.0% and 86.4% for CAZ compared with CTF. The C-statistic was 0.978 for CTF and CTX, 0.953 for CPDX, and 0.798 for CAZ. For the TGCs evaluated in our study, testing for CTX susceptibility results showed the highest correlation with the results given when testing for CTF susceptibility.

In vitro activity of antimicrobial agents with and without sulbactam, EDTA and sulbactam-EDTA on ESBLs-producing Escherichia coli isolated from healthy Tibetan yaks

2020 ◽  
Author(s):  
Baoguang Liu ◽  
Xiaoling Yuan ◽  
Yiheng Chen ◽  
Xiaoshen Li ◽  
Ming Bai ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Nasal Swab ◽  
Antimicrobial Agents ◽  
Synergistic Effects ◽  
E Coli ◽  
Microdilution Method ◽  
Broth Microdilution Method ◽  
Third Generation Cephalosporins ◽  
Enhance Activity

Abstract Background The spread of ESBLs-producing bacteria has been strikingly rapid in many regions of the world and it causes therapeutic difficulties in everyday practice. The aims of this study were to investigate the prevalence and susceptibilities of ESBLs-producing Escherichia coli isolates from healthy Tibetan yaks in China, to evaluate the activity of drug combinations on ESBLs-producing E. coli isolates. Methods From July 2018 to August 2019, a total of 750 nasal swab samples were tested for the presence of E. coli and ESBLs-producing strains. The MICs of 11 antimicrobial agents alone and combinations with sulbactam, EDTA or sulbactam-EDTA against 240 ESBLs-producing E.coli strains were determined by the broth microdilution method. Results Overall, 59.87% (n = 449) of the samples were positive for E. coli, 240 (53.45%) of 449 E. coli isolates were confirmed to be ESBLs-producing. The addition of sulbactam to the third generation cephalosporins, amikacin and fosfomycin for all isolates resulted in low MICs, increasing the level of susceptibility from 0, 0 and 0% to 50 ~ 87.5, 4.2 and 100% respectively. The addition of EDTA to fluoroquinolones, doxycycline, florfenicol, amikacin and fosfomycin, showed improved activities and resulted in low MICs, increasing the level of susceptibility from 0, 0, 8.3, 0 and 0% to 4.2 ~ 29.2, 33.3, 33.3, 66.7 and 45.8%, respectively. All other antibacterials (except fluoroquinolones, doxycycline and florfenicol), when combined with sulbactam-EDTA, were found to be more active than combinations only with sulbactam or with EDTA against most of isolates, with lower MIC50s and MIC90s. Conclusion In conclusion, ESBLs-producing E. coli isolates were widespread in healthy Tibetan yaks in China. ESBLs-producing E. coli isolates exhibited varying degrees of multidrug resistance. This study these findings suggested that sulbactam can enhance activity of β-lactams and some non-β-lactams of antimicrobial agents and had a synergistic effects with EDTA in improving activities of some families of antimicrobials.

scholarly journals In VitroSynergistic Effect of Curcumin in Combination with Third Generation Cephalosporins against Bacteria Associated with Infectious Diarrhea

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Nishanth Kumar Sasidharan ◽  
Sreerag Ravikumar Sreekala ◽  
Jubi Jacob ◽  
Bala Nambisan
Keyword(s):  
Synergistic Effect ◽  
New Combination ◽  
Normal Fibroblast ◽  
Infectious Diarrhea ◽  
Combination Drug ◽  
Microdilution Method ◽  
Broth Microdilution Method ◽  
Time Kill ◽  
Third Generation Cephalosporins

Diarrhea is one of the leading causes of morbidity and mortality in humans in developed and developing countries. Furthermore, increased resistance to antibiotics has resulted in serious challenges in the treatment of this infectious disease worldwide. Therefore, there exists a need to develop alternative natural or combination drug therapies. The aim of the present study was to investigate the synergistic effect of curcumin-1 in combination with three antibiotics against five diarrhea causing bacteria. The antibacterial activity of curcumin-1 and antibiotics was assessed by the broth microdilution method, checkerboard dilution test, and time-kill assay. Antimicrobial activity of curcumin-1 was observed against all tested strains. The MICs of curcumin-1 against test bacteria ranged from 125 to 1000 μg/mL. In the checkerboard test, curcumin-1 markedly reduced the MICs of the antibiotics cefaclor, cefodizime, and cefotaxime. Significant synergistic effect was recorded by curcumin-1 in combination with cefotaxime. The toxicity of curcumin-1 with and without antibiotics was tested against foreskin (FS) normal fibroblast and no significant cytotoxicity was observed. From our result it is evident that curcumin-1 enhances the antibiotic potentials against diarrhea causing bacteria inin vitrocondition. This study suggested that curcumin-1 in combination with antibiotics could lead to the development of new combination of antibiotics against diarrhea causing bacteria.

scholarly journals In VitroAntistaphylococcal Effects ofEmbelia schimperiExtracts and Their Component Embelin with Oxacillin and Tetracycline

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Johana Rondevaldova ◽  
Olga Leuner ◽  
Alemtshay Teka ◽  
Ermias Lulekal ◽  
Jaroslav Havlik ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Medicinal Plants ◽  
Bacterial Infections ◽  
Inhibitory Concentration ◽  
Developed Countries ◽  
Positive Interactions ◽  
Fractional Inhibitory Concentration ◽  
Broth Microdilution ◽  
Microdilution Method ◽  
Broth Microdilution Method

Bacterial infections are in less-developed countries traditionally treated by remedies prepared from medicinal plants.Embelia schimperi(Vatke) is a plant used as a taenicide or disinfectant in Ethiopia, very often taken mixed with another plant species. In the present study, we examined two extracts prepared from seeds and twigs with leaves ofE. schimperiand its main present secondary metabolite embelin for their antibacterial combinatory effect with oxacillin and tetracycline against sensitive and resistantStaphylococcus aureusstrains. Minimum inhibitory concentrations were determined through the broth microdilution method, whereas the combinatory effect was evaluated through fractional inhibitory concentration sum (ΣFIC) indices. Results show many positive interactions and synergy occurring in embelin and oxacillin combinations against 4 out of 9 strains (ΣFIC 0.203–0.477) and for embelin and tetracycline combination against 3 out of 9 strains (ΣFIC 0.400–0.496). Moreover, the resistance to oxacillin has been overcome in 2 strains and to tetracycline in 3 strains. According to our knowledge, this is the first study showing antimicrobial combinatory effect ofE. schimperias well as of embelin. These findings can be used for the further research targeted on the development of new antistaphylococcal agents.

scholarly journals Correlation of In Vitro Activity, Serum Levels, and In Vivo Efficacy of Posaconazole against Rhizopus microsporus in a Murine Disseminated Infection

2009 ◽  
Vol 53 (12) ◽  
pp. 5022-5025 ◽  
Author(s):  
M. Mar Rodríguez ◽  
F. Javier Pastor ◽  
Enrique Calvo ◽  
Valentina Salas ◽  
Deanna A. Sutton ◽  
...  
Keyword(s):  
Serum Levels ◽  
Rhizopus Microsporus ◽  
In Vitro Susceptibility ◽  
In Vivo Efficacy ◽  
Susceptibility Data ◽  
Microdilution Method ◽  
Drug Concentrations ◽  
Broth Microdilution Method

ABSTRACT A broth microdilution method was used to evaluate the in vitro activities of seven antifungal agents against 15 clinical strains of Rhizopus microsporus. Amphotericin B (AMB) and posaconazole (POS) were the most active drugs. In a model of disseminated R. microsporus infection in immunosuppressed mice, we studied the efficacy of POS administered once or twice daily against four of the strains previously tested in vitro and compared it with that of liposomal AMB (LAMB). LAMB was the most effective treatment for the two strains with intermediate susceptibility to POS. For the two POS-susceptible strains, LAMB and POS at 20 mg/kg of body weight twice a day orally showed similar efficacies. The in vivo efficacy of POS administered twice a day orally correlated with the in vitro susceptibility data and the serum drug concentrations.

Antimicrobial Resistance in Campylobacter jejuni from Broilers and Broiler House Environments in Norway

2007 ◽  
Vol 70 (3) ◽  
pp. 736-738 ◽  
Author(s):  
M. NORSTRÖM ◽  
G. JOHNSEN ◽  
M. HOFSHAGEN ◽  
H. THARALDSEN ◽  
H. KRUSE
Keyword(s):  
Antimicrobial Resistance ◽  
Campylobacter Jejuni ◽  
Antimicrobial Susceptibility ◽  
Antimicrobial Agents ◽  
Monitoring Program ◽  
Outdoor Environment ◽  
Susceptibility Data ◽  
Microdilution Method ◽  
Broth Microdilution Method ◽  
Broiler House

Antimicrobial susceptibility in Campylobacter jejuni collected from the environment outside four broiler houses (n = 63) and from the environment inside these broiler houses (including broiler droppings) (n = 36) from May to September 2004 was studied and compared with isolates from Norwegian broilers analyzed within the frame of the Norwegian monitoring program of antimicrobial resistance in feed, food, and animals (NORM-VET) in 2004 (n = 75). The MICs of oxytetracycline, ampicillin, erythromycin, gentamicin, enrofloxacin, and nalidixic acid were obtained by the broth microdilution method VetMIC. The present study, which to our knowledge is the first Norwegian study on the occurrence of antimicrobial resistance in Campylobacter spp. from the environment of broiler houses, revealed a very low occurrence of antimicrobial resistance in C. jejuni from the broilers and broiler house environments studied. All isolates originating from the four broiler houses studied were susceptible to all the antimicrobial agents tested, except for one isolate from the outdoor environment (courtyard soil), which was resistant to oxytetracycline (MIC, 8 mg/liter). For the isolates from broilers (NORM-VET), low prevalences of resistance to oxytetracycline (1.3%) and ampicillin (4%) were observed. No quinolone resistance was observed. The results for the broiler isolates are in agreement with the earlier findings of a very low prevalence of resistance in Campylobacter from broilers in Norway, which reflects the low usage of antimicrobials in Norwegian broiler production. Furthermore, the present data are in accordance with antimicrobial susceptibility data for C. jejuni from domestically acquired human cases.

scholarly journals Understanding and predicting ciprofloxacin minimum inhibitory concentration in Escherichia coli with machine learning

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Bálint Ármin Pataki ◽  
◽  
Sébastien Matamoros ◽  
Boas C. L. van der Putten ◽  
Daniel Remondini ◽  
...  
Keyword(s):  
Machine Learning ◽  
Escherichia Coli ◽  
Minimum Inhibitory Concentration ◽  
Inhibitory Concentration ◽  
Model Concept ◽  
Susceptibility Data ◽  
Genome Wide ◽  
Antimicrobial Resistance Genes ◽  
Machine Learning Approach ◽  
Near Future

Abstract It is important that antibiotics prescriptions are based on antimicrobial susceptibility data to ensure effective treatment outcomes. The increasing availability of next-generation sequencing, bacterial whole genome sequencing (WGS) can facilitate a more reliable and faster alternative to traditional phenotyping for the detection and surveillance of AMR. This work proposes a machine learning approach that can predict the minimum inhibitory concentration (MIC) for a given antibiotic, here ciprofloxacin, on the basis of both genome-wide mutation profiles and profiles of acquired antimicrobial resistance genes. We analysed 704 Escherichia coli genomes combined with their respective MIC measurements for ciprofloxacin originating from different countries. The four most important predictors found by the model, mutations in gyrA residues Ser83 and Asp87, a mutation in parC residue Ser80 and presence of the qnrS1 gene, have been experimentally validated before. Using only these four predictors in a linear regression model, 65% and 93% of the test samples’ MIC were correctly predicted within a two- and a four-fold dilution range, respectively. The presented work does not treat machine learning as a black box model concept, but also identifies the genomic features that determine susceptibility. The recent progress in WGS technology in combination with machine learning analysis approaches indicates that in the near future WGS of bacteria might become cheaper and faster than a MIC measurement.

scholarly journals National Prevalence of Resistance to Third-Generation Cephalosporins in Escherichia coli Isolates from Layer Flocks in France

2013 ◽  
Vol 57 (12) ◽  
pp. 6351-6353 ◽  
Author(s):  
Claire Chauvin ◽  
Laetitia Le Devendec ◽  
Eric Jouy ◽  
Maena Le Cornec ◽  
Sylvie Francart ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Confidence Interval ◽  
Egg Production ◽  
Generation Cephalosporin ◽  
Gene Control ◽  
Third Generation ◽  
Content Type ◽  
E Coli ◽  
National Prevalence ◽  
Third Generation Cephalosporins

ABSTRACTResistance ofEscherichia colito third-generation cephalosporin (3GC) in fecal samples representative of French egg production was studied. The susceptibility to cefotaxime ofE. coliisolates obtained by culture on nonselective media was determined. Twenty-two nonsusceptible isolates were obtained (7.51%; 95% confidence interval, 4.49 to 10.54%), the majority of which came from young birds. Most isolates carried ablaCTX-M-1group gene, and a few carried ablaCMY-2-like gene. Control of 3GC resistance in laying hens is needed.

scholarly journals Outbreak of CTX-M-15-Producing Enterotoxigenic Escherichia coli O159:H20 in the Republic of Korea in 2016

2017 ◽  
Vol 61 (9) ◽  
Author(s):  
Jin Seok Kim ◽  
Jungsun Park ◽  
Eunkyung Shin ◽  
Soojin Kim ◽  
Sung Suck Oh ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
High School ◽  
Food Samples ◽  
Enterotoxigenic Escherichia Coli ◽  
Republic Of Korea ◽  
Third Generation ◽  
Content Type ◽  
The Republic ◽  
Third Generation Cephalosporins

ABSTRACT We investigated an outbreak of enterotoxigenic Escherichia coli (ETEC) O159:H20 associated with the consumption of a tossed-noodle dish in a high school in 2016. Thirty-three ETEC strains isolated from clinical and food samples were genetically indistinguishable. The outbreak strains were resistant to third-generation cephalosporins and harbored a bla CTX-M-15 gene on a 97-kb self-transferable IncK plasmid. This is the first outbreak caused by CTX-M-15-producing ETEC strains.

scholarly journals Antibacterial Activity of 2-(3’,5'-Dibromo-2'-methoxyphenoxy)-3,5-dibromophenol Isolated from Phyllospongia papyracea

2017 ◽  
Vol 12 (4) ◽  
pp. 1934578X1701200 ◽  
Author(s):  
Shi Sun ◽  
Corene Canning ◽  
Kuiwu Wang ◽  
Wenjun Zhu ◽  
Fei Yang ◽  
...  
Keyword(s):  
Antibacterial Agents ◽  
Inhibitory Concentration ◽  
Methanol Extract ◽  
Minimal Bactericidal Concentration ◽  
Antimicrobial Compound ◽  
Highly Active ◽  
Microdilution Method ◽  
Broth Microdilution Method ◽  
Bioassay Guided Fractionation ◽  
And Staphylococcus Aureus

A principal active antimicrobial compound, 2-(3’,5'-dibromo-2'-methoxyphenoxy)-3,5-dibromophenol, was isolated from the methanol extract of Phyllospongia papyracea via bioassay-guided fractionation and isolation. The crude extract and the purified compound were assayed to determine the minimal inhibitory concentration and minimal bactericidal concentration (MBC) using the broth microdilution method. The purified compound was found to be highly active against Bacillus subtilis and Staphylococcus aureus at MIC=1 μg/mL, Campylobacter jejuni at MIC=2 μg/mL, Pseudomonas aeruginosa at MIC=4 μg/mL, and Streptococcus pneumoniae and Listeria monocytogenes at MIC = 8 μg/mL. The activity of this compound was found to be comparable with antibiotics commonly used to control these species of bacteria. The results establish 2-(3’,5'-dibromo-2'-methoxyphenoxy)-3,5-dibromophenol as a potential lead molecule for the development of antibacterial agents.

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