Determination of the De Novo Minimum Selection Concentration of Trimethoprim In Vivo for Using A Pilot Study.

We investigated whether the maximum residual levels of trimethoprim permitted in food (Acceptable Daily Intake-ADI) could select for de novo trimethoprim resistance in in vivo. We designed chronic infection models of in and exposed them to sub-ADI doses of trimethoprim through a single-dosing regimen. The emergence of trimethoprim resistance was determined by isolating the target bacteria on selective agar plates, followed by species confirmation using MALDI-TOF mass spectrometry.

Measuring individual colony MICs is a more sensitive method to detect the effect of antimicrobials on antimicrobial susceptibility than the proportion of colonies resistant.

Unlabelled: The ResistAZM randomized controlled trial found that the receipt of ceftriaxone/azithromycin, compared to ceftriaxone was not associated with an increase in the proportion of oral commensal Neisseria spp. and streptococci with azithromycin resistance 14 days after treatment. We repeated the analyses by measuring the minimum inhibitory concentrations (MICs) of azithromycin and ceftriaxone for individual colonies of commensal Neisseria spp.

Ciprofloxacin Concentrations in Food Could Select for Quinolone Resistance in : An In Vivo Study in .

: The use of antimicrobials to treat food animals leaves antimicrobial residues in foodstuffs. The World Health Organization (WHO) defines the acceptable daily intakes (ADIs) of these residues as the dose of these antimicrobials that is safe for an average human to consume on a daily basis. We hypothesized that the lowest dose of ciprofloxacin classified as safe by the WHO could select for ciprofloxacin-resistant strains of in a model.

Macrolide resistance is pervasive in oral streptococci in the Belgian general population: a cross-sectional survey.

Commensal streptococci are common inhabitants of the oral microbiome and regulate its structure and function in beneficial ways for human health. They can, however, also be opportunistic pathogens and act as a reservoir of resistance genes that can be passed on to other bacteria, including pathogens. Little is known about the prevalence of these commensals in parents and their children and their antimicrobial susceptibilities in the Belgian general population.

Antimicrobial susceptibility of commensal Neisseria spp. in parents and their children in Belgium: a cross-sectional survey.

Background: commensal Neisseria species are part of the oropharyngeal microbiome and play an important role in nitrate reduction and protecting against colonization by pathogenic bacteria. They do, however, also serve as a reservoir of antimicrobial resistance. Little is known about the prevalence of these species in the general population, how this varies by age and how antimicrobial susceptibility varies between species.

The Prevalence of Antibiotic Tolerance in Varies by Anatomical Site.

Background: Tolerance enables bacteria to survive intermittent antibiotic exposure without an increase in antimicrobial susceptibility. In this study, we investigated the presence of tolerance to three antimicrobials, ceftriaxone, azithromycin and ciprofloxacin, in clinical isolates and the WHO (World Health Organization) reference panel of .

Methods: We used the modified tolerance disk (TD test) to assess for tolerance to ceftriaxone, azithromycin and ciprofloxacin in 14 WHO reference strains and 62 clinical isolates-evenly divided between anorectal and urogenital infections.

The effect of daily usage of Listerine Cool Mint mouthwash on the oropharyngeal microbiome: a substudy of the PReGo trial.

Listerine is a bactericidal mouthwash widely used to prevent oral health problems such as dental plaque and gingivitis. However, whether it promotes or undermines a healthy oral microbiome is unclear. We hypothesized that the daily use of Listerine Cool Mint would have a significant impact on the oropharyngeal microbiome.

Effect of erythromycin residuals in food on the development of resistance in : an study in .

Background: The use of antimicrobials to treat food animals may result in antimicrobial residues in foodstuffs of animal origin. The European Medicines Association (EMA) and World Health Organization (WHO) define safe antimicrobial concentrations in food based on acceptable daily intakes (ADIs). It is unknown if ADI doses of antimicrobials in food could influence the antimicrobial susceptibility of human-associated bacteria.

Could traces of fluoroquinolones in food induce ciprofloxacin resistance in and ? An study in with important implications for maximum residue limits in food.

We hypothesized that the residual concentrations of fluoroquinolones allowed in food (acceptable daily intake-ADIs) could select for ciprofloxacin resistance in our resident microbiota. We developed models of chronic and infection in larvae and exposed them to ADI doses of ciprofloxacin via single dosing and daily dosing regimens. The emergence of ciprofloxacin resistance was assessed via isolation of the target bacteria in selective agar plates.

Protective effect of microbisporicin (NAI-107) against vancomycin resistant Enterococcus faecium infection in a Galleria mellonella model.

Increasing antimicrobial resistance in Enterococcus faecium necessitates the search for novel treatment agents, such as bacteriocins. In this study, we conducted an in vivo assessment of five bacteriocins, namely Lacticin Z, Lacticin Q, Garvicin KS (ABC), Aureocin A53 and Microbisporicin (NAI-107), against vanB-resistant Enterococcus faecium using a Galleria mellonella model. Our in vitro experiments demonstrated the efficacy of all five bacteriocins against vanB-resistant E.

Gonococcal resistance to zoliflodacin could emerge via transformation from commensal Neisseria species. An in-vitro transformation study.

One of the most promising new treatments for gonorrhoea currently in phase 3 clinical trials is zoliflodacin. Studies have found very little resistance to zoliflodacin in currently circulating N. gonorrhoeae strains, and in-vitro experiments demonstrated that it is difficult to induce resistance.

Ramoplanin as a novel therapy for infection: an and study in .

is a bacterial pathogen that causes gonorrhoea, a sexually transmitted infection. Increasing antimicrobial resistance in is providing motivation to develop new treatment options. In this study, we investigated the effectiveness of the antibiotic ramoplanin as a treatment for infection.

Chronic High-Level Parasitemia in HIV-Infected Individuals With or Without Visceral Leishmaniasis in an Endemic Area in Northwest Ethiopia: Potential Superspreaders?

Background: People with human immunodeficiency virus (PWH) with recurrent visceral leishmaniasis (VL) could potentially drive Leishmania transmission in areas with anthroponotic transmission such as East Africa, but studies are lacking. Leishmania parasitemia has been used as proxy for infectiousness.

Methods: This study is nested within the Predicting Visceral Leishmaniasis in HIV-InfectedPatients (PreLeisH) prospective cohort study, following 490 PWH free of VL at enrollment for up to 24-37 months in northwest Ethiopia.

Microbisporicin (NAI-107) protects from infection with .

We screened 66 bacteriocins to see if they exhibited anti-gonococcal activity. We found 12 bacteriocins with anti-gonococcal effects, and 4 bacteriocins showed higher anti-gonococcal activity. Three bacteriocins, lacticin Z, lacticin Q, and Garvicin KS (ABC), showed anti-gonococcal activity but no inhibitory effects against the (WHO-P) isolate.

Doxycycline PEP can induce doxycycline resistance in in a model of PEP.

Background: Four randomized controlled trials have now established that doxycycline post exposure (sex) prophylaxis (PEP) can reduce the incidence of chlamydia and syphilis in men who have sex with men. These studies have concluded that the risk of selecting for antimicrobial resistance is low. We evaluated this risk and using a infection model.

Evidence of horizontal gene transfer within in 19 018 whole-genome spp. isolates: a global phylogenetic analysis.

The PorB porins are the major pore-forming proteins in the genus . The trimeric PorB porins consist of 16 highly conserved transmembrane domains that form an amphipathic β-sheet connected by short periplasmic turns and eight extracellular hydrophilic loops. These loops are immunogenic and also play an important role in mediating antimicrobial influx.

Enolase Is Implicated in the Emergence of Gonococcal Tolerance to Ceftriaxone.

Antibiotic tolerance is associated with antibiotic treatment failure, and molecular mechanisms underlying tolerance are poorly understood. We recently succeeded in inducing tolerance to ceftriaxone (CRO) in an reference isolate. In a prior in vitro study, six biological replicates of WHO P strains were exposed to CRO (10× the MIC) followed by overnight growth, and tolerance was assessed using a modified Tolerance Disc (T.

Detection of asymptomatic Leishmania infection in blood donors at two blood banks in Ethiopia.

Visceral leishmaniasis (VL) is a disease caused by Leishmania parasites. While predominantly transmitted by sandflies, cases of VL transmitted through blood transfusion have been reported, particularly in immunocompromised recipients. Although Leishmania parasites have been found in blood donors in some VL endemic areas, this has never been studied in East-Africa, where HIV prevalence is relatively high.

Pre-exposure to azithromycin enhances gonococcal resilience to subsequent ciprofloxacin exposure: an study.

The effect of sequential exposure to different antibiotics is an underexplored topic. Azithromycin can be detected in humans for up to 28 days post-ingestion and may prime bacterial responses to subsequently ingested antibiotics. In this study, we assessed if preexposure to azithromycin could accelerate the acquisition of resistance to ciprofloxacin in reference strain, WHO-F.