Abstract Background. Fever in children is common and mostly caused by self-limiting infections. However, parents of febrile children often consult in general practice, in particular during out-of-hours care. To improve management, it is important to understand experiences of GPs managing these consultations. Objective. To describe GPs’ experiences regarding management of childhood fever during out-ofhours care. Methods. A descriptive qualitative study using purposeful sampling, five focus group discussions were held among 37 GPs. Analysis was based on constant comparative technique using open and axial coding. Results. Main categories were: (i) Workload and general experience; (ii) GPs’ perceptions of determinants of consulting behaviour; (iii) Parents’ expectations from the GP’s point of view; (iv) Antibiotic prescribing decisions; (v) Uncertainty of GPs versus uncertainty of parents and (vi) Information exchange during the consultation. GPs felt management of childhood fever imposes a considerable workload. They perceived a mismatch between parental concerns and their own impression of illness severity, which combined with time–pressure can lead to frustration. Diagnostic uncertainty is driven by low incidences of serious infections and dealing with parental demand for antibiotics is still challenging. Conclusion. Children with a fever account for a high workload during out-of-hours GP care which provides a diagnostic challenge due to the low incidence of serious illnesses and lacking longterm relationship. This can lead to frustration and drives antibiotics prescription rates. Improving information exchange during consultations and in the general public to young parents, could help provide a safety net thereby enhancing self-management, reducing consultations and workload, and subsequent antibiotic prescriptions.
Penicillin acylase (PA) from Escherichia coli can catalyze the coupling of an acyl group to penicillin- and cephalosporin-derived beta-lactam nuclei, a conversion that can be used for the industrial synthesis of beta-lactam antibiotics. The modest synthetic properties of the wild-type enzyme make it desirable to engineer improved mutants. Analysis of the crystal structure of PA has shown that residues alphaR145 and alphaF146 undergo extensive repositioning upon binding of large ligands to the active site, suggesting that these residues may be good targets for mutagenesis aimed at improving the catalytic performance of PA. Therefore, site-saturation mutagenesis was performed on both positions and a complete set of all 38 variants was subjected to rapid HPLC screening for improved ampicillin synthesis. Not less than 33 mutants showed improved synthesis, indicating the importance of the mutated residues in PA-catalyzed acyl transfer kinetics. In several mutants at low substrate concentrations, the maximum level of ampicillin production was increased up to 1.5-fold, and the ratio of the synthetic rate over the hydrolytic rate was increased 5-15-fold. Moreover, due to increased tendency of the acyl-enzyme intermediate to react with beta-lactam nucleophile instead of water, mutants alphaR145G, alphaR145S and alphaR145L demonstrated an enhanced synthetic yield over wild-type PA at high substrate concentrations. This was accompanied by an increased conversion of 6-APA to ampicillin as well as a decreased undesirable hydrolysis of the acyl donor. Therefore, these mutants are interesting candidates for the enzymatic production of semi-synthetic beta-lactam antibiotics.
Background: Elective implant removal (IR) after fracture fixation is one of the most common procedures within (orthopedic) trauma surgery. The rate of surgical site infections (SSIs) in this procedure is quite high, especially below the level of the knee. Antibiotic prophylaxis is not routinely prescribed, even though it has proved to lower SSI rates in other (orthopedic) trauma surgical procedures. The primary objective is to study the effectiveness of a single intravenous dose of 2 g of cefazolin on SSIs after IR following fixation of foot, ankle and/or lower leg fractures. Methods: This is a multicenter, double-blind placebo controlled trial with a superiority design, including adult patients undergoing elective implant removal after fixation of a fracture of foot, ankle, lower leg or patella. Exclusion criteria are: an active infection, current antibiotic treatment, or a medical condition contraindicating prophylaxis with cefazolin including allergy. Patients are randomized to receive a single preoperative intravenous dose of either 2 g of cefazolin or a placebo (NaCl). The primary analysis will be an intention-to-treat comparison of the proportion of patients with a SSI at 90 days after IR in both groups. Discussion: If 2 g of prophylactic cefazolin proves to be both effective and cost-effective in preventing SSI, this would have implications for current guidelines. Combined with the high infection rate of IR which previous studies have shown, it would be sufficiently substantiated for guidelines to suggest protocolled use of prophylactic antibiotics in IR of foot, ankle, lower leg or patella. Trial registration Nederlands Trial Register (NTR): NL8284, registered on 9th of January 2020, https://www.trialregister.nl/trial/8284
To treat microbial infections, antibiotics are life-saving but the increasing antimicrobial resistance is a World-wide problem. Therefore, there is a great need for novel antimicrobial substances. Fruit and flower anthocyanins have been recognized as promising alternatives to traditional antibiotics. How-ever, for future application as innovative alternative antibiotics, the full potential of anthocyanins should be further investigated. The antimicrobial potential of anthocyanin mixtures against different bacterial species has been demonstrated in literature. Preliminary experiments performed by our laboratories, using grape, rose and red cabbage anthocyanins against S. aureus and E. coli confirmed the antimicrobial potential of these substances. Hundreds of different anthocyanin entities have been described. However, which of these entities hold antimicrobial effects is currently unknown. Our preliminary data show that an-thocyanins extracted from grape, rose and red cabbage contain different collections of anthocyanin entities with differential antimicrobial efficacies. Our focus is on the extraction and characterization of anthocyanins from various crop residues. Grape peels are residues in the production of wine, while red rose and tulip leaves are residues in the production of tulip bulbs and regular horticulture. The presence of high-grade substances for pharmacological purposes in these crops may provide an innovative strategy to add value to other-wise invaluable crop residues. This project will be performed by the collaborative effort of our institute together with the Medi-cal Microbiology department of the University Medical Center Groningen (UMCG), 'Wijnstaete', a small-scale wine-producer (Lemelerveld) and Imenz Bioengineering (Groningen), a company that develops processes to improve the production of biobased chemicals from waste products. Within this project, we will focus on the antimicrobial efficacy of anthocyanin-mixtures from sources that are abundantly and locally available as a residual waste product. The project is part of a larger re-search effect to further characterize, modify and study the antimicrobial effects of specific anthocy-anin entities.
Worldwide over- and misuse of antibiotics has contributed to the development of antibiotic-resistance. The occurrence and increase of antibiotic-resistance is one of the most pressing global health care issues of the 21st century. Recently it has been recognized that fruit and flower anthocyanins have antimicrobial activity and thereby the potential to function as novel antibiotics. At the Hanze University of Applied Science, we were able to confirm the antimicrobial efficacy of purified Rosa and Tulipa anthocyanin extracts against an array of microbial species. Using our optimized extraction methods, anthocyanins can easily be extracted and purified from floral residual streams. Once marketed as novel antimicrobials, this valorization of residual streams to high-value compounds contributes to the transition towards a circular economy. However, for future application in different antimicrobial products, it is necessary to identify and characterize single antimicrobial anthocyanin molecules. Moreover, analysis of pilot-scale extraction- and fractionation-yields and antimicrobial bench-mark doses will provide information on their market and application potential. In the current project we propose to develop a strategy composed of fractionation and state-of-the-art characterization methods to identify anthocyanin-molecules with potent antimicrobial effects. To our knowledge this is the first strategy that combines in-depth chemical characterization of anthocyanins in relation to their antimicrobial efficacy. Once developed, this strategy will allow us to single out anthocyanin molecules with antimicrobial properties. The development of the proposed fractionation and characterization strategy is the first step towards the development of single anthocyanin molecules as novel plant-based antibiotics.
Antimicrobial Resistance (AMR), the ability of micro-organisms to resist antibiotics, is associated with ~4.9 million deaths globally, reported in 2022. In the EU alone, more than 35.000 people die from antimicrobial-resistant infections annually, resulting in loss of life as well as €1.5Bn/year in healthcare costs and productivity losses. Rapid diagnostics tests are needed, current testing takes between 24 hours to a few days (for slow growing microorganisms), delaying patient treatment and severely impacting treatment outcomes. SoundCell BV have developed a technique (TRL5), for real-time detection of bacteria's viability in the presence of antibiotics. Nano-mechanical vibration of an ultrathin graphene sheet correlates to viability of bacteria immobilized on this sheet. Bacterial motion is transferred to this sheet, and movement of this sheet is tracked via a high-speed laser. Living bacteria produce a strong signal, which diminishes when antibiotics kill them. Unaffected by growth rates, results are achieved in one hour with this technique. This technology opens up possibility for rapid diagnostics of antibiotic resistance in patients with infections of slow growing pathogens (such as mycobacteria and yeast). In such cases the time to result is slowest, significantly delaying effective patient treatment. We aim to validate this technique in our clinical microbiology laboratory.
