Canine model for investigating the impact of oral enrofloxacin on commensal coliforms and colonization with multidrug-resistant Escherichia coli

2004 ◽  
Vol 53 (5) ◽  
pp. 439-443 ◽  
Author(s):  
Darren J. Trott ◽  
Lucio J. Filippich ◽  
John C. Bensink ◽  
Mary T. Downs ◽  
Suzanne E. McKenzie ◽  
...  

A model was developed in dogs to determine the impact of oral enrofloxacin administration on the indigenous coliform population in the gastrointestinal tract and subsequent disposition to colonization by a strain of multidrug-resistant Escherichia coli (MDREC). Dogs given a daily oral dose of 5 mg enrofloxacin kg−1 for 21 consecutive days showed a significant decline in faecal coliforms to levels below detectable limits by 72 h of administration. Subsequently, faecal coliforms remained suppressed throughout the period of enrofloxacin dosing. Upon termination of antibiotic administration, the number of excreted faecal coliforms slowly returned over an 8-day period, to levels comparable to those seen prior to antibiotic treatment. Enrofloxacin-treated dogs were more effectively colonized by MDREC, evidenced by a significantly increased count of MDREC in the faeces (7.1 ± 1.5 log10 g−1) compared with non-antibiotic-treated dogs (5.2 ± 1.2; P = 0.003). Furthermore, antibiotic treatment also sustained a significantly longer period of MDREC excretion in the faeces (26.8 ± 10.5 days) compared with animals not treated with enrofloxacin (8.5 ± 5.4 days; P = 0.0215). These results confirm the importance of sustained delivery of an antimicrobial agent to maintain and expand the colonization potential of drug-resistant bacteria in vivo, achieved in part by reducing the competing commensal coliforms in the gastrointestinal tract to below detectable levels in the faeces. Without in vivo antimicrobial selection pressure, commensal coliforms dominated the gastrointestinal tract at the expense of the MDREC population. Conceivably, the model developed could be used to test the efficacy of novel non-antibiotic strategies aimed at monitoring and controlling gastrointestinal colonization by multidrug-resistant members of the Enterobacteriaceae that cause nosocomial infections.

2020 ◽  
Vol 15 (3) ◽  
pp. 193-206
Author(s):  
Brognara Lorenzo ◽  
Salmaso Luca ◽  
Mazzotti Antonio ◽  
Di M. Alberto ◽  
Faldini Cesare ◽  
...  

Background: Chronic wounds are commonly associated with polymicrobial biofilm infections. In the last years, the extensive use of antibiotics has generated several antibiotic-resistant variants. To overcome this issue, alternative natural treatments have been proposed, including the use of microorganisms like probiotics. The aim of this manuscript was to review current literature concerning the application of probiotics for the treatment of infected chronic wounds. Methods: Relevant articles were searched in the Medline database using PubMed and Scholar, using the keywords “probiotics” and “wound” and “injuries”, “probiotics” and “wound” and “ulcer”, “biofilm” and “probiotics” and “wound”, “biofilm” and “ulcer” and “probiotics”, “biofilm” and “ulcer” and “probiotics”, “probiotics” and “wound”. Results: The research initially included 253 articles. After removal of duplicate studies, and selection according to specific inclusion and exclusion criteria, 19 research articles were included and reviewed, accounting for 12 in vitro, 8 in vivo studies and 2 human studies (three articles dealing with animal experiments included also in vitro testing). Most of the published studies about the effects of probiotics for the treatment of infected chronic wounds reported a partial inhibition of microbial growth, biofilm formation and quorum sensing. Discussion: The application of probiotics represents an intriguing option in the treatment of infected chronic wounds with multidrug-resistant bacteria; however, current results are difficult to compare due to the heterogeneity in methodology, laboratory techniques, and applied clinical protocols. Lactobacillus plantarum currently represents the most studied strain, showing a positive application in burns compared to guideline treatments, and an additional mean in chronic wound infections. Conclusions: Although preliminary evidence supports the use of specific strains of probiotics in certain clinical settings such as infected chronic wounds, large, long-term clinical trials are still lacking, and further research is needed.


Author(s):  
Chiara Treghini ◽  
Alfonso Dell’Accio ◽  
Franco Fusi ◽  
Giovanni Romano

AbstractChronic lung infections are among the most diffused human infections, being often associated with multidrug-resistant bacteria. In this framework, the European project “Light4Lungs” aims at synthesizing and testing an inhalable light source to control lung infections by antimicrobial photoinactivation (aPDI), addressing endogenous photosensitizers only (porphyrins) in the representative case of S. aureus and P. aeruginosa. In the search for the best emission characteristics for the aerosolized light source, this work defines and calculates the photo-killing action spectrum for lung aPDI in the exemplary case of cystic fibrosis. This was obtained by applying a semi-theoretical modelling with Monte Carlo simulations, according to previously published methodology related to stomach infections and applied to the infected trachea, bronchi, bronchioles and alveoli. In each of these regions, the two low and high oxygen concentration cases were considered to account for the variability of in vivo conditions, together with the presence of endogenous porphyrins and other relevant absorbers/diffusers inside the illuminated biofilm/mucous layer. Furthermore, an a priori method to obtain the “best illumination wavelengths” was defined, starting from maximizing porphyrin and light absorption at any depth. The obtained action spectrum is peaked at 394 nm and mostly follows porphyrin extinction coefficient behavior. This is confirmed by the results from the best illumination wavelengths, which reinforces the robustness of our approach. These results can offer important indications for the synthesis of the aerosolized light source and definition of its most effective emission spectrum, suggesting a flexible platform to be considered in further applications.


Antibiotics ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 228
Author(s):  
Michaela Projahn ◽  
Jana Sachsenroeder ◽  
Guido Correia-Carreira ◽  
Evelyne Becker ◽  
Annett Martin ◽  
...  

Cefotaxime (CTX)-resistant Enterobacteriaceae are still an ongoing challenge in human and veterinary health. High prevalence of these resistant bacteria is detected in broiler chickens and the prevention of their dissemination along the production pyramid is of major concern. The impact of certain on-farm interventions on the external bacterial contamination of broiler chickens, as well as their influence on single processing steps and (cross-) contamination, have not yet been evaluated. Therefore, we investigated breast skin swab samples of broiler chickens before and during slaughter at an experimental slaughter facility. Broiler chickens were previously challenged with CTX-resistant Escherichia coli strains in a seeder-bird model and subjected to none (control group (CG)) or four different on-farm interventions: drinking water supplementation based on organic acids (DW), slow growing breed Rowan × Ranger (RR), reduced stocking density (25 kg/sqm) and competitive exclusion with Enterobacteriales strain IHIT36098(CE). Chickens of RR, 25 kg/sqm, and CE showed significant reductions of the external contamination compared to CG. The evaluation of a visual scoring system indicated that wet and dirty broiler chickens are more likely a vehicle for the dissemination of CTX-resistant and total Enterobacteriaceae into the slaughterhouses and contribute to higher rates of (cross-) contamination during processing.


Author(s):  
Gabriele Sganga ◽  
Mohamed Baguneid ◽  
Pascal Dohmen ◽  
Evangelos J. Giamarellos-Bourboulis ◽  
Emilio Romanini ◽  
...  

AbstractSurgical site infections represent a considerable burden for healthcare systems. To obtain a consensus on the impact and future clinical and economic needs regarding SSI management in an era of multidrug resistance. A modified Delphi method was used to obtain consensus among experts from five European countries. The Delphi questionnaire was assembled by a steering committee, verified by a panel of experts and administered to 90 experts in 8 different surgical specialities (Abdominal, Cancer, Cardiac, General surgery, Orthopaedic, Thoracic, Transplant and Vascular and three other specialities (infectious disease, internal medicine microbiology). Respondents (n = 52) reached consensus on 62/73 items including that resistant pathogens are an increasing matter of concern and increase both treatment complexity and the length of hospital stay. There was strong positive consensus on the cost-effectiveness of early discharge (ED) programs, improvement of quality of life with ED and association between increased length of stay and economic burden to the hospital. However, established ED protocols were not widely available in their hospitals. Respondents expressed a positive consensus on the usefulness of antibiotics that allow ED. Surgeons are aware of their responsibility in an interdisciplinary team for the treatment of SSI, and of the impact of multidrug-resistant bacteria in the context of SSI. Reducing the length of hospital stays by applying ED protocols and implementing new treatment alternatives is crucial to reduce harm to patients and costs for the hospital.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kaitlin S. Witherell ◽  
Jason Price ◽  
Ashok D. Bandaranayake ◽  
James Olson ◽  
Douglas R. Call

AbstractMultidrug-resistant bacteria are a growing global concern, and with increasingly prevalent resistance to last line antibiotics such as colistin, it is imperative that alternative treatment options are identified. Herein we investigated the mechanism of action of a novel antimicrobial peptide (CDP-B11) and its effectiveness against multidrug-resistant bacteria including Escherichia coli #0346, which harbors multiple antibiotic-resistance genes, including mobilized colistin resistance gene (mcr-1). Bacterial membrane potential and membrane integrity assays, measured by flow cytometry, were used to test membrane disruption. Bacterial growth inhibition assays and time to kill assays measured the effectiveness of CDP-B11 alone and in combination with colistin against E. coli #0346 and other bacteria. Hemolysis assays were used to quantify the hemolytic effects of CDP-B11 alone and in combination with colistin. Findings show CDP-B11 disrupts the outer membrane of E. coli #0346. CDP-B11 with colistin inhibits the growth of E. coli #0346 at ≥ 10× lower colistin concentrations compared to colistin alone in Mueller–Hinton media and M9 media. Growth is significantly inhibited in other clinically relevant strains, such as Acinetobacter baumannii, Pseudomonas aeruginosa, and Klebsiella pneumoniae. In rich media and minimal media, the drug combination kills bacteria at a lower colistin concentration (1.25 μg/mL) compared to colistin alone (2.5 μg/mL). In minimal media, the combination is bactericidal with killing accelerated by up to 2 h compared to colistin alone. Importantly, no significant red blood hemolysis is evident for CDP-B11 alone or in combination with colistin. The characteristics of CDP-B11 presented here indicate that it can be used as a potential monotherapy or as combination therapy with colistin for the treatment of multidrug-resistant infections, including colistin-resistant infections.


2019 ◽  
Vol 25 (37) ◽  
pp. 4946-4967 ◽  
Author(s):  
Anna K. Kiss ◽  
Jakub P. Piwowarski

The popularity of food products and medicinal plant materials containing hydrolysable tannins (HT) is nowadays rapidly increasing. Among various health effects attributable to the products of plant origin rich in gallotannins and/or ellagitannins the most often underlined is the beneficial influence on diseases possessing inflammatory background. Results of clinical, interventional and animal in vivo studies clearly indicate the antiinflammatory potential of HT-containing products, as well as pure ellagitannins and gallotannins. In recent years a great emphasis has been put on the consideration of metabolism and bioavailability of natural products during examination of their biological effects. Conducted in vivo and in vitro studies of polyphenols metabolism put a new light on this issue and indicate the gut microbiota to play a crucial role in the health effects following their oral administration. The aim of the review is to summarize the knowledge about HT-containing products’ phytochemistry and their anti-inflammatory effects together with discussion of the data about observed biological activities with regards to the current concepts on the HTs’ bioavailability and metabolism. Orally administered HT-containing products due to the limited bioavailability of ellagitannins and gallotannins can influence immune response at the level of gastrointestinal tract as well as express modulating effects on the gut microbiota composition. However, due to the chemical changes being a result of their transit through gastrointestinal tract, comprising of hydrolysis and gut microbiota metabolism, the activity of produced metabolites has to be taken into consideration. Studies regarding biological effects of the HTs’ metabolites, in particular urolithins, indicate their strong and structure-dependent anti-inflammatory activities, being observed at the concentrations, which fit the range of their established bioavailability. The impact of HTs on inflammatory processes has been well established on various in vivo and in vitro models, while influence of microbiota metabolites on silencing the immune response gives a new perspective on understanding anti-inflammatory effects attributed to HT containing products, especially their postulated effectiveness in inflammatory bowel diseases (IBD) and cardiovascular diseases.


2021 ◽  
Vol 12 ◽  
Author(s):  
Quentin Vallé ◽  
Béatrice B. Roques ◽  
Alain Bousquet-Mélou ◽  
David Dahlhaus ◽  
Felipe Ramon-Portugal ◽  
...  

The increase of multidrug-resistant (MDR) bacteria has renewed interest in old antibiotics, such as minocycline, that can be active against various MDR Gram-negative pathogens. The elimination of minocycline by both kidneys and liver makes it suitable for impaired renal function patients. However, the drawback is the possible elimination of a high amount of drug in the intestines, with potential impact on the digestive microbiota during treatment. This study aimed to predict the potential activity of minocycline against Enterobacterales in the gut after parenteral administration, by combining in vivo and in vitro studies. Total minocycline concentrations were determined by UPLC-UV in the plasma and intestinal content of piglets following intravenous administration. In parallel, the in vitro activity of minocycline was assessed against two Escherichia coli strains in sterilized intestinal contents, and compared to activity in a standard broth. We found that minocycline concentrations were 6–39 times higher in intestinal contents than plasma. Furthermore, minocycline was 5- to 245-fold less active in large intestine content than in a standard broth. Using this PK-PD approach, we propose a preclinical pig model describing the link between systemic and gut exposure to minocycline, and exploring its activity against intestinal Enterobacterales by taking into account the impact of intestinal contents.


2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Akihisa Hata ◽  
Noboru Fujitani ◽  
Fumiko Ono ◽  
Yasuhiro Yoshikawa

AbstractThere is a lack of an established antimicrobial resistance (AMR) surveillance system in animal welfare centers. Therefore, the AMR prevalence in shelter dogs is rarely known. Herein, we conducted a survey in animal shelters in Chiba and Kanagawa prefectures, in the Kanto Region, Japan, to ascertain the AMR status of Escherichia coli  (E. coli) prevalent in shelter dogs. E. coli was detected in the fecal samples of all 61 and 77 shelter dogs tested in Chiba and Kanagawa, respectively. The AMR was tested against 20 antibiotics. E. coli isolates derived from 16.4% and 26.0% of samples from Chiba and Kanagawa exhibited resistance to at least one antibiotic, respectively. E. coli in samples from Chiba and Kanagawa prefectures were commonly resistant to ampicillin, piperacillin, streptomycin, kanamycin, tetracycline, and nalidixic acid; that from the Kanagawa Prefecture to cefazolin, cefotaxime, aztreonam, ciprofloxacin, and levofloxacin and that from Chiba Prefecture to chloramphenicol and imipenem. Multidrug-resistant bacteria were detected in 18 dogs from both regions; β-lactamase genes (blaTEM, blaDHA-1, blaCTX-M-9 group CTX-M-14), quinolone-resistance protein genes (qnrB and qnrS), and mutations in quinolone-resistance-determining regions (gyrA and parC) were detected. These results could partially represent the AMR data in shelter dogs in the Kanto Region of Japan.


Author(s):  
Nahla Omer Eltai ◽  
Hadi M. Yassine ◽  
Sara H. Al-Hadidi ◽  
Tahra ElObied ◽  
Asmaa A. Al Thani ◽  
...  

The dissemination of antimicrobial resistance (AMR) bacteria has been associated with the inappropriate use of antibiotics in both humans and animals and with the consumption of food contaminated with resistant bacteria. In particular, the use of antibiotics as prophylactic and growth promotion purposes in food-producing animals has rendered many of the antibiotics ineffective. The increased global prevalence of AMR poses a significant threat to the safety of the world’s food supply. Objectives: This study aims at determining the prevalence of antibiotic-resistant Escherichia coli (E. coli) isolated from local and imported retail chicken meat in Qatar. Methodology: A total of 270 whole chicken carcasses were obtained from three different hypermarket stores in Qatar. A total of 216 E. coli were isolated and subjected to antibiotic susceptibility testing against 18 relevant antibiotics using disc diffusion and micro- dilution methods. Furthermore, extended-spectrum β-lactamase (ESBL) production was determined via a double-disc synergetic test. Isolates harboring colistin resistance were confirmed using multiplex-PCR and DNA sequencing. Results: Nearly 89% (192/216) of the isolates were resistant to at least one antibiotics. In general, isolates showed relatively higher resistance to sulfamethoxazole (62%), tetracycline (59.7%), ampicillin and trimethoprim (52.3%), ciprofloxacin (47.7%), cephalothin, and colistin (31.9%). On the other hand, less resistance was recorded against amoxicillin/clavulanic acid (6%), ceftriaxone (5.1%), nitrofurantoin (4.2%) and piperacillin/tazobactam (4.2%), cefepime (2.3%), meropenem (1.4%), ertapenem (0.9%), and amikacin (0.9%). Nine isolates (4.2%) were ESBL producers. Furthermore, 63.4% were multidrug-resistant (MDR). The percentage of MDR, ESBL producers, and colistin-resistant isolates was significantly higher among local isolates compared to imported chicken samples. Conclusion: We reported a remarkably high percentage of the antibiotic-resistant E. coli in chicken meat sold at retail in Qatar. The high percentage of MDR and colistin isolates is troublesome to the food safety of raw chicken meat and the potential of antibiotic resistance spread to public health. Our findings support the need for the implementation of one health approach to address the spread of antimicrobial resistance and the need for a collaborative solution.


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