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356 نتائج ل "Keywords: antibiotics"
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Association of Diet and Antimicrobial Resistance in Healthy U.S. Adults
Antimicrobial resistance (AMR) represents a considerable burden to health care systems, with the public health community largely in consensus that AMR will be a major cause of death worldwide in the coming decades. Humans carry antibiotic resistance in the microbes that live in and on us, collectively known as the human microbiome. Antimicrobial resistance (AMR) represents a significant source of morbidity and mortality worldwide, with expectations that AMR-associated consequences will continue to worsen throughout the coming decades. Since resistance to antibiotics is encoded in the microbiome, interventions aimed at altering the taxonomic composition of the gut might allow us to prophylactically engineer microbiomes that harbor fewer antibiotic resistant genes (ARGs). Diet is one method of intervention, and yet little is known about the association between diet and antimicrobial resistance. To address this knowledge gap, we examined diet using the food frequency questionnaire (FFQ; habitual diet) and 24-h dietary recalls (Automated Self-Administered 24-h [ASA24 ® ] tool) coupled with an analysis of the microbiome using shotgun metagenome sequencing in 290 healthy adult participants of the United States Department of Agriculture (USDA) Nutritional Phenotyping Study. We found that aminoglycosides were the most abundant and prevalent mechanism of AMR in these healthy adults and that aminoglycoside- O -phosphotransferases ( aph3-dprime ) correlated negatively with total calories and soluble fiber intake. Individuals in the lowest quartile of ARGs (low-ARG) consumed significantly more fiber in their diets than medium- and high-ARG individuals, which was concomitant with increased abundances of obligate anaerobes, especially from the family Clostridiaceae , in their gut microbiota. Finally, we applied machine learning to examine 387 dietary, physiological, and lifestyle features for associations with antimicrobial resistance, finding that increased phylogenetic diversity of diet was associated with low-ARG individuals. These data suggest diet may be a potential method for reducing the burden of AMR. IMPORTANCE Antimicrobial resistance (AMR) represents a considerable burden to health care systems, with the public health community largely in consensus that AMR will be a major cause of death worldwide in the coming decades. Humans carry antibiotic resistance in the microbes that live in and on us, collectively known as the human microbiome. Diet is a powerful method for shaping the human gut microbiome and may be a tractable method for lessening antibiotic resistance, and yet little is known about the relationship between diet and AMR. We examined this relationship in healthy individuals who contained various abundances of antibiotic resistance genes and found that individuals who consumed diverse diets that were high in fiber and low in animal protein had fewer antibiotic resistance genes. Dietary interventions may be useful for lessening the burden of antimicrobial resistance and might ultimately motivate dietary guidelines which will consider how nutrition can reduce the impact of infectious disease.
A Biological Signature for the Inhibition of Outer Membrane Lipoprotein Biogenesis
Gram-negative bacteria have an outer membrane, which acts as a protective barrier and excludes many antibiotics. The limited number of antibiotics active against Gram-negative bacteria, along with rising rates of antibiotic resistance, highlights the need for efficient antibiotic discovery efforts. The outer membrane (OM) of Gram-negative bacteria is an essential organelle that acts as a formidable barrier to antibiotics. Increasingly prevalent resistance to existing drugs has exacerbated the need for antibiotic discovery efforts targeting the OM. Acylated proteins, known as lipoproteins, are essential in every pathway needed to build the OM. The central role of OM lipoproteins makes their biogenesis a uniquely attractive therapeutic target, but it also complicates in vivo identification of on-pathway inhibitors, as inhibition of OM lipoprotein biogenesis broadly disrupts OM assembly. Here, we use genetics to probe the eight essential proteins involved in OM lipoprotein maturation and trafficking. We define a biological signature consisting of three simple assays that can characteristically identify OM lipoprotein biogenesis defects in vivo . We find that several known chemical inhibitors of OM lipoprotein biogenesis conform to the biological signature. We also examine MAC13243, a proposed inhibitor of OM lipoprotein biogenesis, and find that it fails to conform to the biological signature. Indeed, we demonstrate that MAC13243 activity relies entirely on a target outside of the OM lipoprotein biogenesis pathway. Hence, our signature offers simple tools to easily assess whether antibiotic lead compounds target an essential pathway that is the hub of OM assembly. IMPORTANCE Gram-negative bacteria have an outer membrane, which acts as a protective barrier and excludes many antibiotics. The limited number of antibiotics active against Gram-negative bacteria, along with rising rates of antibiotic resistance, highlights the need for efficient antibiotic discovery efforts. Unfortunately, finding the target of lead compounds, especially ones targeting outer membrane construction, remains difficult. The hub of outer membrane construction is the lipoprotein biogenesis pathway. We show that defects in this pathway result in a signature cellular response that can be used to quickly and accurately validate pathway inhibitors. Indeed, we found that MAC13243, a compound previously proposed to target outer membrane lipoprotein biogenesis, does not fit the signature, and we show that it instead targets an entirely different cellular pathway. Our findings offer a streamlined approach to the discovery and validation of lead antibiotics against a conserved and essential pathway in Gram-negative bacteria.
iTDtest: an Easy-to-Handle and Visual Assay To Detect Tolerant and Persister Cells in an Antibiotic Combination Regimen
In a recent article, Balaban and colleagues developed the iTDtest allowing characterization of the type of interactions between different antibiotics at bactericidal concentrations (J.-F. Liu et al., mBio 13:e00004-22, 2022). In a recent article, Balaban and colleagues developed the iTDtest allowing characterization of the type of interactions between different antibiotics at bactericidal concentrations (J.-F. Liu et al., mBio 13:e00004-22, 2022). This visual and semiquantitative assay is designed to determine how antibiotic cocktails affect tolerance and persistence, two phenomena of major importance for the eradication of difficult-to-treat pathogens. Importantly, Balaban and colleagues identified antibiotic combinations allowing for complete clearance of persister and tolerant cells. This commentary discusses the translation of this assay in clinical settings, where antibiotic combination therapies appear to be applied in specific contexts, such as in acute infections or in the case of multidrug or extensively drug-resistant pathogens.
Evidence of Antibiotic Resistance from Population-Based Studies: A Narrative Review
The 20th century witnessed the dawn of the antibiotic revolution and is now facing the rising phenomenon of antibiotic resistance. In this narrative review, we aim to describe antibiotic resistance in clinical practice settings through population-based studies from different countries reporting the role of misuse of antibiotics in the development of resistance and the clinical and economic burden associated. The misuse of antibiotics was documented in the wide population as well as in hospitals and care facilities. It was mainly reported as over-use and inappropriate prescribing. Improper dosage regimens and longer treatment duration were regarded as pivotal factors related to antibiotic resistance; the emerging strategy of \"antibiotic-de-escalation\" could be the key to overcome these issues. The investigation of the self-medication attitude revealed widespread antibiotic use without following medical instructions or medical consultation. Moreover, several studies established the association of antibiotic resistance with increased risk of longer hospitalizations and mortality, highlighting the heavy clinical and economic burden of this phenomenon. In this narrative review, the widespread inappropriate use of antibiotics emerged as one of the main causes of antibiotic resistance, which negative outcomes call for the development of antibiotic stewardship programs and global surveillance networks.
A Retrospective Analysis of the Bacterial Infections, Antibiotic Use, and Mortality Predictors of COVID-19 Patients
This study aimed to investigate the rate and profile of bacterial infections, mortality-associated predictors, and report the most common microorganisms and antibiotic use in coronavirus disease-19 (COVID-19) patients. This study used a retrospective approach to evaluate the bacterial culture, antibiotic use, comorbidities, imaging, and laboratory discoveries of patients with COVID-19 (hospitalized) confirmed by reverse transcription polymerase chain reaction (RT-PCR) between May and December 2020. We have selected 906 COVID-19 positive patients using a consecutive sampling technique and analyzed data using IBM SPSS-22 statistical software. Statistical analysis included univariate, bivariate, and multivariate analysis. It was carried out using multivariable logistic regression analysis to predict the mortality of COVID-19 patients. A total of 410 patients, which involved 247 males with a mean age of 53.9 years were evaluated. Based on the results, the positive bacterial culture was detected in 18.3% of all patients who sent the culture sample test, representing bacterial infections. The was the most commonly identified organism, while the proportion of patients treated with antibiotics was 83.4%. Furthermore, azithromycin was prescribed in the highest number of patients with approximately 44.3% of all antibiotics. The total mortality rate was 39.8% and its ratio was higher in COVID-19 patients with bacterial infections (65.3%, X = 25.1, <0.001). Patients mortality who used antibiotics were also higher compared to those who did not (89% vs 11%, <0.014). Age, length of hospitalization, bacterial infection, shortness of breath, neutrophil-to-lymphocyte ratio (NLR), and diabetes mellitus were also associated predictors to increased hospital mortality (adjusted OR (aOR) 0.382, <0.013; aOR 4.265, <0.001; aOR 3.720, <0.001; aOR 3.889, <0.001; aOR 6.839, <0.003; aOR 1.844, <0.030), respectively. This study discovered that there is high use of antibiotics amongst COVID-19 patients; however, the bacterial infection rates did not exceed one-fifth of the total patients. Furthermore, older age, bacterial infections, a longer length of hospitalization, diabetes mellitus, shortness of breath, and higher NLR have a significant impact on the mortality of COVID-19 patients.
A Silent Operon of Photorhabdus luminescens Encodes a Prodrug Mimic of GTP
Drug-resistant Gram-negative bacteria have become the major problem driving the antimicrobial resistance crisis. Searching outside the overmined actinomycetes, we focused on Photorhabdus , gut symbionts of enthomopathogenic nematodes that carry up to 40 biosynthetic gene clusters coding for secondary metabolites. With the overmining of actinomycetes for compounds acting against Gram-negative pathogens, recent efforts to discover novel antibiotics have been focused on other groups of bacteria. Teixobactin, the first antibiotic without detectable resistance that binds lipid II, comes from an uncultured Eleftheria terra , a betaproteobacterium; odilorhabdins, from Xenorhabdus , are broad-spectrum inhibitors of protein synthesis, and darobactins from Photorhabdus target BamA, the essential chaperone of the outer membrane of Gram-negative bacteria. Xenorhabdus and Photorhabdus are symbionts of the nematode gut microbiome and attractive producers of secondary metabolites. Only small portions of their biosynthetic gene clusters (BGC) are expressed in vitro. To access their silent operons, we first separated extracts from a small library of isolates into fractions, resulting in 200-fold concentrated material, and then screened them for antimicrobial activity. This resulted in a hit with selective activity against Escherichia coli , which we identified as a novel natural product antibiotic, 3′-amino 3′-deoxyguanosine (ADG). Mutants resistant to ADG mapped to gsk and gmk , kinases of guanosine. Biochemical analysis shows that ADG is a prodrug that is converted into an active ADG triphosphate (ADG-TP), a mimic of GTP. ADG incorporates into a growing RNA chain, interrupting transcription, and inhibits cell division, apparently by interfering with the GTPase activity of FtsZ. Gsk of the purine salvage pathway, which is the first kinase in the sequential phosphorylation of ADG, is restricted to E. coli and closely related species, explaining the selectivity of the compound. There are probably numerous targets of ADG-TP among GTP-dependent proteins. The discovery of ADG expands our knowledge of prodrugs, which are rare among natural compounds. IMPORTANCE Drug-resistant Gram-negative bacteria have become the major problem driving the antimicrobial resistance crisis. Searching outside the overmined actinomycetes, we focused on Photorhabdus , gut symbionts of enthomopathogenic nematodes that carry up to 40 biosynthetic gene clusters coding for secondary metabolites. Most of these are silent and do not express in vitro . To gain access to silent operons, we first fractionated supernatant from Photorhabdus and then tested 200-fold concentrated material for activity. This resulted in the isolation of a novel antimicrobial, 3′-amino 3′-deoxyguanosine (ADG), active against E. coli . ADG is an analog of guanosine and is converted into an active ADG-TP in the cell. ADG-TP inhibits transcription and probably numerous other GTP-dependent targets, such as FtsZ. Natural product prodrugs have been uncommon; discovery of ADG broadens our knowledge of this type of antibiotic.
Peri-Operative Prophylaxis in Patients of Neonatal and Pediatric Age Subjected to Cardiac and Thoracic Surgery: A RAND/UCLA Appropriateness Method Consensus Study
Surgical site infections (SSIs) represent a potential complication of surgical procedures, with a significant impact on mortality, morbidity, and healthcare costs. Patients undergoing cardiac surgery and thoracic surgery are often considered patients at high risk of developing SSIs. This consensus document aims to provide information on the management of peri-operative antibiotic prophylaxis for the pediatric and neonatal population undergoing cardiac and non-cardiac thoracic surgery. The following scenarios were considered: (1) cardiac surgery for the correction of congenital heart disease and/or valve surgery; (2) cardiac catheterization without the placement of prosthetic material; (3) cardiac catheterization with the placement of prosthetic material; (4) implantable cardiac defibrillator or epicardial pacemaker placement; (5) patients undergoing ExtraCorporal Membrane Oxygenation; (6) cardiac tumors and heart transplantation; (7) non-cardiac thoracic surgery with thoracotomy; (8) non-cardiac thoracic surgery using video-assisted thoracoscopy; (9) elective chest drain placement in the pediatric patient; (10) elective chest drain placement in the newborn; (11) thoracic drain placement in the trauma setting. This consensus provides clear and shared indications, representing the most complete and up-to-date collection of practice recommendations in pediatric cardiac and thoracic surgery, in order to guide physicians in the management of the patient, standardizing approaches and avoiding the abuse and misuse of antibiotics.
Surgical Antimicrobial Prophylaxis in Neonates and Children Undergoing Neurosurgery: A RAND/UCLA Appropriateness Method Consensus Study
Pediatric neurosurgery is a highly specialized branch of surgery in which surgical site infections (SSIs) are potentially serious complications that can also adversely affect a good surgical outcome, compromising functional recovery and, in some cases, even putting the patient’s life at risk. The main aim of this consensus document is to provide clinicians with a series of recommendations on antimicrobial prophylaxis for neonates and children undergoing neurosurgery. The following scenarios were considered: (1) craniotomy or cranial/cranio-facial approach to craniosynostosis; (2) neurosurgery with a trans-nasal-trans-sphenoidal approach; (3) non-penetrating head injuries; (4) penetrating head fracture; (5) spinal surgery (extradural and intradural); (6) shunt surgery or neuroendoscopy; (7) neuroendovascular procedures. Patients undergoing neurosurgery often undergo peri-operative antibiotic prophylaxis, with different schedules, not always supported by scientific evidence. This consensus provides clear and shared indications, based on the most updated literature. This work has been made possible by the multidisciplinary contribution of experts belonging to the most important Italian scientific societies, and represents, in our opinion, the most complete and up-to-date collection of recommendations on the behavior to be held in the peri-operative setting in this type of intervention, in order to guide physicians in the management of the patient, standardize approaches and avoid abuse and misuse of antibiotics.
What influences antibiotic sales in rural Bangladesh? A drug dispensers’ perspective
Background Antibiotic resistance poses a great threat to global health, especially in low- and middle-income countries with a high infectious disease burden and limited resources. In spite of regulations, antibiotics are sold in many settings as non-prescription medicines, resulting in inappropriate use and resistance. Objective This study aimed to investigate the current status of access and use of antibiotics in rural Bangladesh, by exploring the perspectives and sales practices of antibiotic drug dispensers. Methods We used a mixed methods approach (qualitative and quantitative). We mapped and characterized antibiotic purchasing and dispensing sites in the Matlab Health and Demographic Surveillance System catchment area. Furthermore, we investigated the volume of provision of systemic antibiotics in 10 drug outlets. We held 16 in-depth interviews with randomly selected antibiotics dispensers. Interviews explored factors associated with antibiotic selling. Responses were transcribed, coded for themes, and summarized. We used ATLAS.ti 5.2 for conducting a thematic analysis. Results A total of 301 antibiotic dispensers were identified, of whom 92% ( n  = 278) were private and 8% ( n  = 23) public. 52% ( n  = 155) operated informally (i.e. without legal authorization). In order to promote and survive in their business, dispensers sell antibiotics for a range of conditions without a qualified physician’s prescription. Factors that facilitate these inappropriate sales include lack of access to healthcare in the rural community, inadequate doctor: population ratio, limited dispenser knowledge, poor pharmacovigilance concerning safety of self medication, lack of enforcement of policies, financial benefits for both customers and dispensers, and high dependency on pharmaceutical companies’ information. Conclusion Dispensers in rural Bangladesh sell antibiotics inappropriately by ignoring existing national regulations. They operate the antibiotic sales without facing any legal barriers and primarily with a view to sustain their business, resulting in inappropriate sales of antibiotics to the rural community. The influence of the drug industry needs to be replaced with evidence-based, not commercially driven information. Awareness programs for antibiotic providers that promote understanding of antibiotics and antibiotic resistance through tailored interventions may be helpful in changing current antibiotic sales practices.
Surgical Antimicrobial Prophylaxis in Pediatric Patients Undergoing Plastic Surgery: A RAND/UCLA Appropriateness Method Consensus Study
For many years, it was clearly shown that surgical procedures might be associated with surgical site infection (SSI). Many scientific institutions prepared guidelines to use in surgery to reduce abuse and misuse of antibiotics. However, in the general guidelines for surgical antibiotic prophylaxis, plastic surgical procedures are not addressed or are only marginally discussed, and children were almost systematically excluded. The main aim of this Consensus document is to provide clinicians with recommendations on antimicrobial prophylaxis for pediatric patients undergoing plastic surgery. The following scenarios were considered: clean plastic surgery in elective procedures with an exclusive skin and subcutis involvement; clean-contaminated/contaminated plastic surgery in elective procedures with an exclusive skin and subcutis involvement; elective plastic surgery with use of local flaps; elective plastic surgery with the use of grafts; prolonged elective plastic surgery; acute burns; clean contused lacerated wounds without bone exposure; high-risk contused lacerated wounds or with bone exposure; contused lacerated wound involving the oral mucosa; plastic surgery following human bite; plastic surgery following animal bite; plastic surgery with tissue expander insertion. Our Consensus document shows that antimicrobial perioperative prophylaxis in pediatric patients undergoing plastic surgery is recommended in selected cases. While waiting the results of further pediatric studies, the application of uniform and shared protocols in these procedures will improve surgical practice, with a reduction in SSIs and consequent rationalization of resources and costs, as well as limiting the phenomenon of antimicrobial resistance.