Frontiers in antibiotics最新文献

Correct use of antibiotics is paramount to present global health. Among other actions, antimicrobial stewardship emphasizes de-escalation and suspension whenever possible. Nonetheless, roadblocks can be encountered (e.g., lack of culture results or availability of specific antibiotic classes). Furthermore, in an ever-increasing interconnected world, global success relies on local success. In this perspective, a particular case study in a resource-limited setting is an example of the many difficulties encountered in the fight against antimicrobial resistance that could hamper global advancements.

Salmonella is a foodborne pathogenic bacterium that causes salmonellosis worldwide. Also, Salmonella is considered a serious problem for food safety and public health. Several antimicrobial classes including aminoglycosides, tetracyclines, phenols, and β-Lactams are used to treat Salmonella infections. Antibiotics have been prescribed for decades to treat infections caused by bacteria in human and animal healthcare. However, intensive use of antibiotics resulted in antibiotic resistance (AR) among several foodborne bacteria including Salmonella. Furthermore, multi-drug resistance (MDR) of Salmonella has increased dramatically. In addition to MDR Salmonella, extensively drug resistant (XDR) as well as pan drug resistant (PDR) Salmonella were reported globally. Therefore, increasing AR is becoming a serious universal public health crisis. Salmonella developed many mechanisms to ensure its survival against antimicrobials. The most prominent defense mechanisms against these antibiotics include enzymatic inactivation, expelling drugs from the cell through efflux pumps, altering the structure of drugs, and changing or protecting the targets of drugs. Additionally, the formation of biofilms and plasmid-mediated AR by Salmonella, enhancing its resistance to various antibiotics, making it a challenging pathogen in both healthcare and food industry settings. This review focuses exclusively on providing a detailed overview of the mechanisms of AR in Salmonella.

Introduction: Antimicrobial resistance (AMR) represents a persistent and ascensive global threat influenced by antibiotic misuse and overuse. In the Romanian context, patterns of antibiotic consumption and resistance within the healthcare system are marked in the red scenario on the European map. General practitioners and pharmacists, among others, play a major role in stewardship towards AMR.

Aim: To explore the practices, strategies, and challenges in antibiotic treatment and prevention of antimicrobial resistance from the perspectives of Romanian community pharmacists and general practitioners.

Method and materials: Semi-structured interviews were conducted with six general practitioners and five community pharmacists in Romania from January to March 2024. An inductive, Goffman theory-inspired thematic analysis was conducted, inspired by Braun and Clarke's thematic analysis method, consisting of familiarization with the data, iterative coding guided by theoretically inspired questions, and identification and refinement of (sub)themes. Goffman's theory of social interaction, focusing on the concepts of front stage, backstage, and roles, guided the analytical questions.

Results: The results were presented in three overarching themes: 'Knowledge acquired backstage to support challenges and performance on front stage', 'Adapting roles and performances on the front stage: A mix of structured and twisted acts', and 'Interprofessional Collaboration: A latent part in the play's roles and performances'. Professionals prepared their understandings of AMR and antibiotics backstage, with an awareness of the challenges rooted in the Romanian context. The front stage scenario evolved from structured antibiotic performances led by AMR strategies with compliant actors to challenging performances influenced by actors which changed the course of performances and intended AMR strategies. The revealed competition between general practitioners and pharmacists further complicated antibiotic use and AMR-related performances.

Conclusion: The Romanian socio-political system influenced the course of antibiotic treatment and the professionals' intended antibiotic related practices and AMR strategies. The study showed a theory-practice gap in health professionals' practices, leading to limited strategy integration towards AMR and increased antibiotic use. The study underscores the need for context-specific policies and interventions to minimize identified gaps.

Neonatal sepsis causes substantial morbidity and mortality, the burden of which is carried by low-income countries (LICs). The emergence of multidrug-resistant pathogens in vulnerable neonatal populations poses an urgent threat to infant survival. Acinetobacter spp. are increasingly responsible for severe disease in neonates globally. The cause of this escalation remains unclear, but host, pathogen and environmental factors are all likely to contribute. Acinetobacter spp. strains are frequently resistant to the first line empirical treatment for neonatal sepsis as recommended by the World Health Organization (WHO), ampicillin and gentamicin, rendering these antibiotics ineffectual in many critically ill neonates. The resultant escalation to broader spectrum antibiotic regimens in neonatal intensive care units (NICUs) worldwide has led to the emergence of more resistant strains, including carbapenem-resistant Acinetobacter baumanii (CRAB), resulting in infections that are ever more difficult to treat. While some existing antimicrobial agents are under consideration for treatment of Acinetobacter spp. infections, the majority remain a long way from clinical use in neonates. Further research into the clinical phenotype of these infections, transmission dynamics and preventative measures are urgently needed to reduce neonatal deaths. This review aims to summarise the role of Acinetobacter spp. in neonatal sepsis, including host, pathogen and environmental factors, the global epidemiology and clinical features of the disease, the treatment options, and future research priorities.

Rifamycin and its derivatives are natural products that belong to the class of antibiotic-active polyketides and have significant therapeutic relevance within the therapy scheme of tuberculosis, a worldwide infectious disease caused by Mycobacterium tuberculosis. Improving the oral bioavailability of rifamycin B was achieved through semisynthetic modifications, leading to clinically effective derivatives such as rifampicin. Genetic manipulation of the rifamycin polyketide synthase gene cluster responsible for the production of rifamycin B in the Amycolatopsis mediterranei strain S699 represents a promising tool to generate new rifamycins. These new rifamycins have the potential to be further derivatized into new, ideally more effective, clinically usable compounds. However, the resulting genetically engineered strains only produce these new derivatives in low yields. One example is the strain DCO36, in which rifAT6 was replaced by rapAT2, resulting in the production of rifamycin B and the new derivative 24-desmethyl rifamycin B. Here we describe the successful method adaptation of the PCR-targeting Streptomyces gene replacement approach to Amycolatopsis mediterranei S699 and further on the implementation of genetic modifications that enable an increased production of the derivative 24-desmethyl rifamycin B in the mutant strain DCO36. The described genetic modifications resulted in a mutant strain of DCO36 with rifQ deletion showing a 62% increase in 24-desmethyl rifamycin B production, while a mutant with rifO overexpression showed a 27% increase.

Microorganisms, crucial for environmental equilibrium, could be destructive, resulting in detrimental pathophysiology to the human host. Moreover, with the emergence of antibiotic resistance (ABR), the microbial communities pose the century's largest public health challenges in terms of effective treatment strategies. Furthermore, given the large diversity and number of known bacterial strains, describing treatment choices for infected patients using experimental methodologies is time-consuming. An alternative technique, gaining popularity as sequencing prices fall and technology advances, is to use bacterial genotype rather than phenotype to determine ABR. Complementing machine learning into clinical practice provides a data-driven platform for categorization and interpretation of bacterial datasets. In the present study, k-mers were generated from nucleotide sequences of pathogenic bacteria resistant to antibiotics. Subsequently, they were clustered into groups of bacteria sharing similar genomic features using the Affinity propagation algorithm with a Silhouette coefficient of 0.82. Thereafter, a prediction model based on Random Forest algorithm was developed to explore the prediction capability of the k-mers. It yielded an overall specificity of 0.99 and a sensitivity of 0.98. Additionally, the genes and ABR drivers related to the k-mers were identified to explore their biological relevance. Furthermore, a multilayer perceptron model with a hamming loss of 0.05 was built to classify the bacterial strains into resistant and non-resistant strains against various antibiotics. Segregating pathogenic bacteria based on genomic similarities could be a valuable approach for assessing the severity of diseases caused by new bacterial strains. Utilization of this strategy could aid in enhancing our understanding of ABR patterns, paving the way for more informed and effective treatment options.

Clinical Microbiology has developed during the last 100 years, simultaneous with the discovery of microorganisms as causes of infections. Globalization and One Health determine present needs whereas molecular biology, automation, artificial intelligence, and bioinformatics are new tools that characterize the new developments in the field.