-
Journal of Infection and Public Health Oct 2023Enterobacterales carrying bla represent an emerging challenge in treating infectious diseases. In this study, we aimed to investigate the characteristics of...
BACKGROUND
Enterobacterales carrying bla represent an emerging challenge in treating infectious diseases. In this study, we aimed to investigate the characteristics of bla-producing Enterobacterales from three hospitals in southern Taiwan.
METHODS
Enterobacterales strains that were nonsusceptible to more than one carbapenem (ertapenem, meropenem, imipenem, or doripenem) were collected from hospitalized patients. Molecular typing for New Delhi metallo-β-lactamase (NDM) and antibiotic susceptibility tests were performed, followed by multilocus sequence typing (MLST), pulsed-field gel electrophoresis (PFGE), and plasmid analysis by PCR-based replicon typing.
RESULTS
A total of 1311 carbapenem-nonsusceptible Enterobacterales were isolated from 2017 to 2021. bla-encoding genes were detected in 108 isolates, with 53 (49.1%) harboring bla and 55 (50.9%) harboring bla. The rate of bla detection among isolates decreased to 2% in 2021. However, the rate of E. coli harboring bla increased from 1% to 12% of total isolates during the study period. Of 47 NDM-5-positive E. coli isolates, 44 (93.6%) were ST8346 with high genetic relatedness. E. coli ST8346 isolates showed high-level resistance to both carbapenems and aminoglycosides. Most (38 out of 47, 80.9%) bla-harboring E. coli isolates co-harbored bla. We analyzed the regions harboring bla in E. coli ST8346 via PCR amplification. bla and bla were located on two separate plasmids, IncF and IncX3, respectively.
CONCLUSION
The dissemination of E. coli ST8346 caused an increase in bla and bla co-harboring Enterobacterales in southern Taiwan, which show high-level resistance to both carbapenems and aminoglycosides. We identified a distinct IncF plasmid encoding bla that has the potential for rapid spread and needs further surveillance.
Topics: Humans; Escherichia coli; Multilocus Sequence Typing; Taiwan; Anti-Bacterial Agents; Carbapenems; Aminoglycosides
PubMed: 37633229
DOI: 10.1016/j.jiph.2023.08.007 -
Zhonghua Jie He He Hu Xi Za Zhi =... Aug 2023To evaluate the activity of six β-lactams in combination with three β-lactamase inhibitors against mycobacterium tuberculosis(MTB) . A total of 105...
To evaluate the activity of six β-lactams in combination with three β-lactamase inhibitors against mycobacterium tuberculosis(MTB) . A total of 105 multidrug-resistant tuberculosis (MDR-TB) strains from different regions of Henan province from January to September 2020 were included in this study. Drug activity of six β-lactams (biapenem, meropenem, imipenem, doripenem, ertapenem and tebipenem) alone or in combination with β-lactamase inhibitors (clavulanic acid, avibactam and relebactam) was examined by minimum inhibitory concentration method (MICs) against 105 clinical isolates. Mutations of , and were analyzed by PCR and DNA sequencing. Chi-square test was used to compare the antimicrobial activities of different β-lactam drugs. Out of the β-lactams used herein, tebipenem was the most effective against MDR-TB and had an MIC value of 8 mg/L(χ=123.70,0.001). Besides, after the addition of β-lactamase inhibitors, the MICs of most β-lactam drugs were reduced more evidently in the presence of avibactam and relebactam compared to clavulanic acid.Especially, relebactam decreased both the MIC50 and MIC90 of telbipenem by 16-fold, and diluted the MIC of 23 (21.90%) and 41 (39.04%) isolatesby 32-fold and 16-fold.In addition, a total of 13.33% (14/105) of isolates harbored mutations in the gene, with three different nucleotide substitutions: AGT333AGG, AAC638ACC and ATC786ATT. For the strains with Ser111Arg and Asn213Thr substitution in BlaC, the MIC values of the meropenem-clavulanate combination were reduced compared with a synonymous single nucleotide polymorphism (SNP) group. Both avibactam and relebactam had better synergistic effects on β-lactams than clavulanic acid. The combination of tebipenem and relebactam showed the most potent activity against MDR-TB isolates. In addition, the Ser111Arg and Asn213Thr substitution of BlaC may be associated with an increased susceptibility of MDR-TB isolates to meropenem in the presence of clavulanate.
Topics: Humans; beta-Lactamase Inhibitors; beta-Lactams; Anti-Bacterial Agents; Meropenem; Mycobacterium tuberculosis; Clavulanic Acid; Tuberculosis, Multidrug-Resistant; Mutation; Microbial Sensitivity Tests; beta-Lactamases
PubMed: 37536990
DOI: 10.3760/cma.j.cn112147-20230111-00017 -
Antibiotics (Basel, Switzerland) Jul 2023() is an opportunistic bacteria responsible for many nosocomial and community-acquired infections. The emergence and spread of antibiotic resistances have resulted in...
() is an opportunistic bacteria responsible for many nosocomial and community-acquired infections. The emergence and spread of antibiotic resistances have resulted in widespread epidemics and endemic dissemination of multidrug-resistant pathogens. A total of 145 isolates were recovered from hospital wastewater effluents and subjected to antibiogram profiling. Furthermore, the antibiotic resistance determinants were assessed among phenotypic resistant isolates using polymerase chain reaction (PCR). The isolates showed a wide range of antibiotic resistance against 21 selected antibiotics under 11 classes, with the most susceptible shown against imipenem (94.5%) and the most resistant shown against ampicillin (86.2%). The isolates also showed susceptibility to piperacillin/tazobactam (89.0%), ertapenem (87.6%), norfloxacin (86.2%), cefoxitin (86.2%), meropenem (76.6%), doripenem (76.6%), gentamicin (76.6%), chloramphenicol (73.1%), nitrofurantoin (71.7%), ciprofloxacin (79.3%), amikacin (60.7%), and amoxicillin/clavulanic acid (70.4%). Conversely, resistance was also recorded against tetracycline (69%), doxycycline (56.6%), cefuroxime (46.2%), cefotaxime (48.3%), ceftazidime (41.4%). Out of the 32 resistance genes tested, 28 were confirmed, with [ (58.8%), (47.89%), (25.2%), (5.9%)], [ (68.4%), (66.6%)], and [ (62.3%), (26%), (14.4%)] genes having the highest occurrence. Strong significant associations exist among the resistance determinants screened. About 82.7% of the isolates were multidrug-resistant (MDR) with a multiple antibiotics resistance index (MARI) range of 0.24 to 1.0. A dual presence of the resistant genes among was also observed to occur more frequently than multiple presences. This study reveals a worrisome presence of multidrug-resistant isolates and resistance genes in hospital waste effluent, resulting in higher public health risks using untreated surface water for human consumption. As a result, adequate water treatment and monitoring initiatives designed to monitor antimicrobial resistance patterns in the aquatic ecosystem are required.
PubMed: 37508235
DOI: 10.3390/antibiotics12071139 -
Antibiotics (Basel, Switzerland) Jun 2023The emergence of multidrug-resistance (MDR)-New Delhi metallo-beta-lactamase (NDM)-producing microorganisms-has become a serious concern for treating such infections....
The emergence of multidrug-resistance (MDR)-New Delhi metallo-beta-lactamase (NDM)-producing microorganisms-has become a serious concern for treating such infections. Therefore, we investigated the effective antimicrobial combinations against multidrug-resistant New Delhi metallo-beta-lactamase-producing strains of . The tests were carried out using the 2D(two-dimensional) checkerboard method. Of 7 antimicrobials, i.e., doripenem (DRP), streptomycin (STR), cefoxitin (FOX), imipenem (IPM), cefotaxime (CTX), meropenem (MER), and gentamicin (GEN), 19 different combinations were used, and out of them, three combinations showed synergistic effects against 31 highly drug-resistant strains carrying and other associated resistance markers. Changes in the minimum inhibitory concentration (MIC) values were interpreted using the test fractional inhibitory concentration index (FIC Index). The FIC Index values of these combinations were found in the range of 0.1562 to 0.5, which shows synergy, whereas no synergism was observed in the remaining antimicrobial combinations. We conclude that these antibiotic combinations can be analyzed in in vivo and pharmacological studies to establish an effective therapeutic approach.
PubMed: 37508229
DOI: 10.3390/antibiotics12071134 -
BioRxiv : the Preprint Server For... Jul 2023During head and neck cancer treatment, off-target ionizing radiation damage to the salivary glands commonly causes a permanent loss of secretory function. Due to the...
During head and neck cancer treatment, off-target ionizing radiation damage to the salivary glands commonly causes a permanent loss of secretory function. Due to the resulting decrease in saliva production, patients have trouble eating, speaking and are predisposed to oral infections and tooth decay. While the radioprotective antioxidant drug Amifostine is approved to prevent radiation-induced hyposalivation, it has intolerable side effects that limit its use, motivating the discovery of alternative therapeutics. To address this issue, we previously developed a salivary gland mimetic (SGm) tissue chip platform. Here, we leverage this SGm tissue chip for high-content drug discovery. First, we developed in-chip assays to quantify glutathione and cellular senescence (β-galactosidase), which are biomarkers of radiation damage, and we validated radioprotection using WR-1065, the active form of Amifostine. Following validation, we tested other reported radioprotective drugs, including, Edaravone, Tempol, N-acetylcysteine (NAC), Rapamycin, Ex-Rad, and Palifermin, confirming that all drugs but NAC and Ex-Rad exhibited robust radioprotection. Next, a Selleck Chemicals library of 438 FDA-approved drugs was screened for radioprotection. We discovered 25 hits, with most of the drugs identified with mechanisms of action other than antioxidant activity. Hits were down-selected using EC values and pharmacokinetics and pharmacodynamics data from the PubChem database leading to testing of Phenylbutazone (anti-inflammatory), Enoxacin (antibiotic), and Doripenem (antibiotic) for radioprotection in mice using retroductal injections. Results confirm that Phenylbutazone and Enoxacin exhibited equivalent radioprotection to Amifostine. This body of work demonstrates the development and validation of assays using a SGm tissue chip platform for high-content drug screening and the successful discovery and validation of novel radioprotective drugs with nonantioxidant primary indications pointing to possible, yet unknown novel mechanisms of radioprotection.
PubMed: 37503292
DOI: 10.1101/2023.07.12.548707 -
International Journal of Food... Oct 2023This study was conducted to investigate the existence and possible transmission routes of CREs during the bovine slaughter process. A total of 600 samples including...
This study was conducted to investigate the existence and possible transmission routes of CREs during the bovine slaughter process. A total of 600 samples including rectoanal mucosal swaps, bovine hides and carcasses were collected weekly, over a 20 week period from three different slaughterhouses in Samsun province and analyzed in terms of CRE. Isolation of CRE was performed using Chromatic CRE Agar. Obtained isolates were identified using PCR and VITEK MS. E-test method was used for screening of carbapenemase production and disk diffusion method was used for detection of phenotypic carbapenem resistance. Presence of five major carbapenemase genes were investigated by PCR and obtained amplicons were sequenced by Sanger sequencing. Clonal relatedness was investigated by Clermont phylo-typing and MLST. Plasmid incompability groups were determined by PCR-based replicon typing. Based on the results, only one bovine hide sample was found positive in terms of CRE and bla harbouring E. coli ST398 (phylogroup A) was identified. E. coli ST398 was found resistant to meropenem, imipenem, ertapenem, doripenem and also tested fluoroquinolones. ST398 was found to harbour three distinct replicons, namely N, FII, and FIB KQ. Inc. groups for these replicons were identified as IncN and IncFII. On the other hand, no concrete evidence has been obtained to suggest that CREs are spreading at the slaughterhouse level. Conclusively, conducting further studies in areas such as farms, pens, and feedlots is necessary to gain a better understanding of the transmission routes of CREs in livestock.
Topics: Cattle; Animals; Carbapenems; Abattoirs; Escherichia coli; Multilocus Sequence Typing; Bacterial Proteins; beta-Lactamases; Imipenem; Microbial Sensitivity Tests; Anti-Bacterial Agents
PubMed: 37422948
DOI: 10.1016/j.ijfoodmicro.2023.110314 -
International Journal of Biological... Jul 2023The increased use of antibiotics worldwide turned into a serious preoccupation due to their environmental and health impacts. Since the majority of antibiotic residuals...
The increased use of antibiotics worldwide turned into a serious preoccupation due to their environmental and health impacts. Since the majority of antibiotic residuals are hardly eliminated from wastewater, based on usual methods, other treatments receive considerable attention. Adsorption is known as the most effective method of the treatment of antibiotics. In this paper, the adsorption isotherms of doripenem, ampicillin, and amoxicillin on bentonite-chitosan composite are determined at three temperatures, T = 303.15, 313.15 and 323.15 K, which are used to achieve a theoretical investigation of the removal phenomenon, based on a statistical physics theory. Three analytical models are utilized to describe the AMO, AMP, and DOR adsorption phenomena at the molecular level. From the fitting results, all antibiotic adsorption on a BC adsorbent is associated with the monolayer formation with one type of site. Concerning the number of adsorbed molecules per site (n), it is concluded that multi-docking (n < 1) and multi-molecular (n > 1) phenomena are feasible for AMO, AMP, and DOR adsorption on BC. The adsorption amounts at saturation of the BC adsorbent, deduced by the monolayer model, are found to be 70.4-88.0 mg/g for doripenem, 57.8-79.2 mg/g for ampicillin and 38.6-67.5 mg/g for amoxicillin indicating that the antibiotics adsorption performance of BC was greatly depended on temperature where the adsorption capacities increased with the increment of this operating variable. All adsorption systems are demonstrated by a calculation of the energy of adsorption, considering that the extrication of these pollutants implies physical interactions. The thermodynamic interpretation confirms the spontaneous and feasible nature of the adsorption of the three antibiotics on BC adsorbent. In brief, BC sample is regarded as a promising adsorbent to extract antibiotics from water and presents important potentials to be effected in wastewater handling at industrial level.
Topics: Anti-Bacterial Agents; Bentonite; Chitosan; Wastewater; Adsorption; Doripenem; Amoxicillin; Ampicillin
PubMed: 37270136
DOI: 10.1016/j.ijbiomac.2023.125156 -
Veterinary Medicine and Science Jul 2023Resistance to multiple drugs in Klebsiella pneumoniae (KPN) is an important issue in human and animal medicine. KPN phenotypic and genotypic aspects in poultry samples...
BACKGROUND
Resistance to multiple drugs in Klebsiella pneumoniae (KPN) is an important issue in human and animal medicine. KPN phenotypic and genotypic aspects in poultry samples have not been comprehensively explored in Bangladesh.
METHODS
This research focused on the prevalence of antibiotic resistance and the characterization of KPN in Bangladeshi poultry isolates using both phenotypic and genotypic approaches.
RESULTS
A total of 32 poultry samples were randomly obtained from a commercial poultry farm in Narsingdi, Bangladesh, and 43.90% (18/41) of the isolates were confirmed to be KPN, whereas all isolates were biofilm producers. The antibiotic sensitivity test revealed the most remarkable (100%) antibiotic resistance level against Ampicillin, Doxycycline and Tetracycline while remaining susceptible to Doripenem, Meropenem, Cefoxitin and Polymyxin B. Resistance to Nalidixic acid, Nitrofurantoin, Trimethoprim, Levofloxacin, Ciprofloxacin, Cefuroxime and Chloramphenicol ranges from 18% to 70%. Minimum inhibitory concentrations for carbapenem-resistant KPN ranged from 128 to 512 mg/mL for Meropenem, Imipenem, Gentamycin and Ciprofloxacin, respectively. [Correction added on 15 June 2023, after first online publication: 512 g/mL was corrected to 512 mg/mL in the preceding sentence]. Carbapenemase-producing KPN isolates harboured a single or multiple β-lactamase genes, bla , bla and bla as well as one ESBL gene (bla ) and plasmid-mediated quinolone resistance gene (qnrB). Furthermore, Cr and Co outperformed Cu and Zn in antibacterial effectiveness.
CONCLUSIONS
The results of this investigation showed that the high prevalence of multidrug-resistant pathogenic KPN in our chosen geographic location had displayed sensitivity to FOX/PB/Cr/Co, which might be regarded as an alternate treatment to reduce pressure of use on carbapenems.
Topics: Humans; Animals; Klebsiella pneumoniae; Meropenem; Bangladesh; Poultry; Anti-Bacterial Agents; beta-Lactamases; Ciprofloxacin; Metals, Heavy
PubMed: 37252894
DOI: 10.1002/vms3.1168 -
International Journal of Antimicrobial... Aug 2023This study aimed to investigate the in vitro susceptibility and β-lactamase-encoding genes of Pseudomonas aeruginosa (P. aeruginosa) isolates with discrepant resistance...
In vitro activities of ceftazidime-avibactam, ceftolozane-tazobactam, meropenem-vaborbactam and other comparators against Pseudomonas aeruginosa isolates with discrepant resistance to carbapenems: Data from the Antimicrobial Testing Leadership and Surveillance (ATLAS) program, 2012-2021.
OBJECTIVES
This study aimed to investigate the in vitro susceptibility and β-lactamase-encoding genes of Pseudomonas aeruginosa (P. aeruginosa) isolates with discrepant resistance to various carbapenems.
METHODS
Data on P. aeruginosa isolates were obtained from the Antimicrobial Testing Leadership and Surveillance program from 2012-2021. Minimum inhibitory concentrations of P. aeruginosa isolates were determined using the broth microdilution method. β-lactamase-encoding genes were identified using multiplex polymerase chain reaction assays.
RESULTS
Among the P. aeruginosa isolates that were tested, the percentages of isolates resistant to imipenem, meropenem and doripenem were 26.9% (14 447 of 53 617), 20.5% (14 098 of 68 897) and 17.5% (3660 of 20 946), respectively. Imipenem-resistant P. aeruginosa isolates were more susceptible to all tested antimicrobial agents (except colistin) than the meropenem-resistant or doripenem-resistant P. aeruginosa isolates. Carbapenemase genes were detected in 14.3% (2020 of 14 098) of meropenem-resistant P. aeruginosa isolates. Imipenem-resistant meropenem-susceptible P. aeruginosa isolates had higher susceptibility profiles, fewer carbapenemase genes (0.3% [five of 1858] vs. 4.1% [10 of 242]; P < 0.05) and a lower risk of being classified as multidrug-resistant than the imipenem-susceptible meropenem-resistant isolates (16.1% [299 of 1858] vs. 73.6% [178 of 242]; P < 0.05). Among all β-lactam combination agents, ceftazidime-avibactam and ceftolozane-tazobactam had higher susceptibility rates than meropenem-vaborbactam for meropenem-resistant P. aeruginosa (61.8% and 55.5% vs. 30.2%; P < 0.05).
CONCLUSION
Discrepancy in the resistance of different P. aeruginosa isolates to various carbapenems suggests their different underlying resistance mechanisms. These findings can be useful for effective resistance trend monitoring and accurate antimicrobial treatment in the future.
Topics: Humans; Pseudomonas aeruginosa; Meropenem; Anti-Bacterial Agents; Carbapenems; Doripenem; Leadership; Pseudomonas Infections; Ceftazidime; Cephalosporins; Tazobactam; Azabicyclo Compounds; Anti-Infective Agents; Imipenem; beta-Lactamases; Microbial Sensitivity Tests
PubMed: 37244423
DOI: 10.1016/j.ijantimicag.2023.106867 -
Foods (Basel, Switzerland) May 2023Farming seabass () is an essential activity in the Mediterranean basin including the Aegean Sea. The main seabass producer is Turkey accounting for 155,151 tons of...
Farming seabass () is an essential activity in the Mediterranean basin including the Aegean Sea. The main seabass producer is Turkey accounting for 155,151 tons of production in 2021. In this study, skin swabs of seabass farmed in the Aegean Sea were analysed with regard to the isolation and identification of . Bacterial microbiota of skin samples ( = 96) from 12 fish farms were investigated using next-generation sequencing (NGS) and metabarcoding analysis. The results demonstrated that Proteobacteria was the dominant bacterial phylum in all samples. At the species level, was identified in all samples. , and were identified using conventional methods and a total of 46 viable (48% of all NGS+) were isolated in seabass swab samples. Additionally, antibiotic susceptibility was determined according to standards of the European Committee on Antimicrobial Susceptibility Testing (EUCAST) and Clinical and Laboratory Standards Institute (CLSI) in psychrotrophic . strains were tested for susceptibility to 11 antibiotics (piperacillin-tazobactam, gentamicin, tobramycin, amikacin, doripenem, meropenem, imipenem, levofloxacin, ciprofloxacin, norfloxacin, and tetracycline) from five different groups of antibiotics (penicillins, aminoglycosides, carbapenems, fluoroquinolones, and tetracyclines). The antibiotics chosen were not specifically linked to usage by the aquaculture industry. According to the EUCAST and CLSI, three and two strains were found to be resistant to doripenem and imipenem (E-test), respectively. All strains were susceptible to piperacillin-tazobactam, amikacin, levofloxacin, and tetracycline. Our data provide insight into different bacteria that are prevalent in the skin microbiota of seabass sampled from the Aegean Sea in Turkey, and into the antibiotic resistance of psychrotrophic spp.
PubMed: 37238774
DOI: 10.3390/foods12101956