To combat the spread of antibiotic resistance into the environment, we should adequately manage wastewater effluent treatment to achieve simultaneous removal of antibiotics, antibiotic resistant ...bacteria (ARB), and antibiotic resistance genes (ARGs). Herein, we fabricate a multifunctional electroactive poly(vinylidene fluoride) ultrafiltration membrane (C/PVDF) by phase inversion on conductive carbon cloth. The membrane possesses not only excellent retention toward ARB and ARGs but also exhibits high oxidation capacity as an electrode. Notably, sulfamethoxazole degradation involving hydroxylation and hydrolysis by the anode membrane is predominant, and the degradation efficiency is up to 81.5% at +4 V. Both electro-filtration processes exhibit significant ARB inactivation, anode filtration is superior to cathode filtration. Moreover, the degradation of intracellular ARGs (iARGs) located in the genome is more efficient than those located in the plasmid, and these degradation efficiencies at −2 V are higher than +2 V. The degradation efficiencies of extracellular ARGs (eARGs) are opposite and are lower than iARGs. Compared with regular filtration, the normalized flux of electroactive ultrafiltration membrane is improved by 18.0% at −2 V, 15.9% at +2 V, and 30.4% at +4 V during treating wastewater effluent, confirming its antifouling properties and feasibility for practical application.
Although aquaculture activity has experienced a great development over the past three decades, infectious diseases have become a limiting factor for further intensification. Because the use of ...antibiotics has led to the widespread emergence of antibiotic resistance, the search for alternative environmentally friendly approaches is urgently needed. This Opinion paper offers an update on the successes and challenges of biological approaches for bacterial disease prevention and control in aquaculture. Although most of these approaches are still in research and development stages, some of them have shown promising results in field trials. Therefore, a better understanding of the mechanisms of action of these approaches will help to maximise their beneficial properties.
Growing global concerns about antibiotic resistance have prompted the search for environmentally friendly approaches for preventing and controlling diseases in aquaculture.
Probiotics, prebiotics, their combination (synbiotics), nonviable bacterial or metabolic byproducts derived from probiotic bacteria (postbiotics), plant-derived natural compounds (phytobiotics), bacteriophages, and quorum sensing interference could be potential alternatives to the use of antibiotics in aquaculture.
Biological approaches used as preventive or therapeutic measures are needed when vaccination is not feasible in juvenile fish or farmed crustaceans and molluscs.
While it is well recognized that the environmental resistome is global, diverse, and augmented by human activities, it has been difficult to assess risk because of the inability to culture many ...environmental organisms, and it is difficult to evaluate risk from current sequence-based environmental methods. The four most important criteria to determine risk are whether the antibiotic-resistance genes (ARGs) are a complete, potentially functional complement; if they are linked with other resistances; whether they are mobile; and the identity of their host. Long-read sequencing fills this important gap between culture and short sequence-based methods. To address these criteria, we collected feces from a ceftiofur-treated cow, enriched the samples in the presence of antibiotics to favor ARG functionality, and sequenced long reads using Nanopore and PacBio technologies. Multidrug-resistance genes comprised 58% of resistome abundance, but only 0.8% of them were plasmid associated; fluroquinolone-, aminoglycoside-, macrolide-lincosamide-streptogramin (MLS)-, and β-lactam-resistance genes accounted for 2.7 to 12.3% of resistome abundance but with 19 to 78% located on plasmids. A variety of plasmid types were assembled, some of which share low similarity to plasmids in current databases. Enterobacteriaceae were dominant hosts of antibiotic-resistant plasmids; physical linkage of extended-spectrum β-lactamase genes (
,
,
, and
) was largely found with aminoglycoside-, MLS-, tetracycline-, trimethoprim-, phenicol-, sulfonamide-, and mercury-resistance genes. A draft circular chromosome of
was assembled; it carries MLS-, tetracycline- (including
and
on an integrative conjugative element), and trimethoprim-resistance genes flanked by many transposase genes and insertion sequences, implying that they remain transferrable.
The occurrence of antibiotics and antibiotic resistance genes in riverine systems has become a growing concern worldwide. Risk prediction of antibiotic resistance is difficult as the continuous ...addition of new antibiotics complicate the antibiotic resistome. As rivers flow with heavy antibiotic burdens, antibiotic resistance develops rapidly and disseminates into various environmental compartments. The analysis of antibiotic contamination-driven resistance in global rivers provides a clear picture of the consequences in the near future. In this review, an extensive literature survey along with the analysis on the relevant data was carried out to offer a better knowledge on the global trend of antibiotic resistance. Although the most common resistance was reported against tetracycline and sulfonamide class of antibiotics, the trend of resistance against advanced generation antibiotics such as β-lactam is alarming. Furthermore, non-therapeutic use of antibiotics as growth promoters has become more frequent than clinical use as a major driver of resistance dissemination. Mechanistically, integrons and mobile genetic elements are suggested as one of the important media for resistance gene transfer. Considering the significance of this emerging issue, special emphasis is placed on the sources, fate, and possible management strategies to mitigate the threat of antibiotic resistance. This review covers the environmental footprints of the antibiotic contamination-mediated emergence and dissemination of antibiotic resistant bacteria and genes in global rivers. As such, the distribution pattern of antibiotic contamination and resistance determinants in various rivers worldwide has been described with a note of its long term impact. The information presented in this review may be useful to policy makers, clinicians, and pharmaceutical companies to tackle the epidemiology of antibiotic resistance as a global threat.
•The data on dissemination of important antibiotics, ARB and ARGs in major rivers are assessed.•The results suggest that antibiotic resistance is an emerging global threat.•Wastewater effluents are major sources of antibiotic resistance dissemination.•Methods of wastewater treatment should be improved for the efficient removal of antibiotics.
The common cooccurrence of antibiotics and phages in both natural and engineered environments underscores the need to understand their interactions and implications for bacterial control and ...antibiotic resistance propagation. Here, aminoglycoside antibiotics that inhibit protein synthesis (e.g., kanamycin and neomycin) impeded the replication of coliphage T3 and
phage BSP, reducing their infection efficiency and mitigating their hindrance of bacterial growth, biofilm formation, and tolerance to antibiotics. For example, treatment with phage T3 reduced subsequent biofilm formation by Escherichia coli liquid cultures to 53% ± 5% of that of the no-phage control, but a smaller reduction of biofilm formation (89% ± 10%) was observed for combined exposure to phage T3 and kanamycin. Despite sharing a similar mode of action with aminoglycosides (i.e., inhibiting protein synthesis) and antagonizing phage replication, albeit to a lesser degree, tetracyclines did not inhibit bacterial control by phages. Phage T3 combined with tetracycline showed higher suppression of biofilm formation than when combined with aminoglycosides (25% ± 6% of the no-phage control). The addition of phage T3 to E. coli suspensions with tetracycline also suppressed the development of tolerance to tetracycline. However, this suppression of antibiotic tolerance development disappeared when tetracycline was replaced with 3 mg/liter kanamycin, corroborating the greater antagonism with aminoglycosides. Overall, this study highlights this overlooked antagonistic effect on phage proliferation, which may attenuate phage suppression of bacterial growth, biofilm formation, antibiotic tolerance, and maintenance of antibiotic resistance genes.
The coexistence of residual antibiotics and phages is common in many environments, which underscores the need to understand their interactive effects on bacteria and the implications for antibiotic resistance propagation. Here, aminoglycosides acting as bacterial protein synthesis inhibitors impeded the replication of various phages. This alleviated the suppressive effects of phages against bacterial growth and biofilm formation and diminished bacterial fitness costs that suppress the emergence of tolerance to antibiotics. We show that changes in bacteria caused by environmentally relevant concentrations of sublethal antibiotics can affect phage-host dynamics that are commonly overlooked
but can result in unexpected environmental consequences.
Background
Awareness of prescribing practices helps identify opportunities to improve antibiotic use (AU).
Objectives
To estimate AU prevalence in dogs and cats in U.S. veterinary teaching hospitals ...(VTHs) and identify antibiotic drugs commonly prescribed, indications for use, and evidence of bacterial infection.
Animals
Medical record data were collected from dogs and cats examined at 14 VTHs.
Methods
Data were collected from VTH medical records of dogs and cats examined by primary care, urgent care, emergency and critical care, internal medicine, and surgery services on a single day during August 13‐September 3, 2020. Data included signalment; clinical service; inpatient or outpatient status; clinical conditions; diagnostic tests; evidence of bacterial infection; intended reason for AU; name and route of antibiotics prescribed.
Results
Of 883 dogs and cats, 322 (36.5%) were prescribed at least 1 antibiotic. Among 285 antibiotics administered systemically intended for treatment of infection, 10.9% were prescribed without evidence of infection. The most common class of antibiotics presribed for systemic administration was potentiated penicillin for dogs (115/346, 33.3%) and cats (27/80, 33.8%). For dogs and cats, first‐generation cephalosporins (93/346, 26.9% and 11/80, 13.8%, respectively) and fluoroquinolones (51/346, 14.7% and 19/80, 23.8%, respectively) was second or third most‐prescribed. Common AU indications included skin, respiratory, and urinary conditions, and perioperative use.
Conclusions and Clinical Importance
Collaborative data collection provides a sustainable methodology to generate national AU prevalence estimates and bring attention to areas requiring additional research and detailed data collection. These efforts can also identify practice improvement opportunities in settings where future veterinarians are trained.
Critically ill patients undergo extensive physiological alterations that will have impact on antibiotic pharmacokinetics. Up to 60% of intensive care unit (ICU) patients meet the pharmacodynamic ...targets of beta-lactam antibiotics, with only 30% in fluoroquinolones. Not reaching these targets might increase the chance of therapeutic failure, resulting in increased mortality and morbidity, and antibiotic resistance. The DOLPHIN trial was designed to demonstrate the added value of therapeutic drug monitoring (TDM) of beta-lactam and fluoroquinolones in critically ill patients in the ICU.
A multi-centre, randomised controlled trial (RCT) was designed to assess the efficacy and cost-effectiveness of model-based TDM of beta-lactam and fluoroquinolones. Four hundred fifty patients will be included within 24 months after start of inclusion. Eligible patients will be randomly allocated to either study group: the intervention group (active TDM) or the control group (non-TDM). In the intervention group dose adjustment of the study antibiotics (cefotaxime, ceftazidime, ceftriaxone, cefuroxime, amoxicillin, amoxicillin with clavulanic acid, flucloxacillin, piperacillin with tazobactam, meropenem, and ciprofloxacin) on day 1, 3, and 5 is performed based upon TDM with a Bayesian model. The primary outcome will be ICU length of stay. Other outcomes amongst all survival, disease severity, safety, quality of life after ICU discharge, and cost effectiveness will be included.
No trial has investigated the effect of early TDM of beta-lactam and fluoroquinolones on clinical outcome in critically ill patients. The findings from the DOLPHIN trial will possibly lead to new insights in clinical management of critically ill patients receiving antibiotics. In short, to TDM or not to TDM?
EudraCT number: 2017-004677-14. Sponsor protocol name: DOLPHIN. Registered 6 March 2018 . Protocol Version 6, Protocol date: 27 November 2019.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The co-occurrence of various chemical and biological contaminants of emerging concerns has hindered the application of water recycling. This study aims to develop a heterogeneous photo-Fenton ...treatment by fabricating nano pyrite (FeS2) on graphene oxide (FeS2@GO) to simultaneously remove antibiotic resistant bacteria (ARB), antibiotic resistance genes (ARGs), and micropollutants (MPs). A facile and solvothermal process was used to synthesize new pyrite-based composites. The GO coated layer forms a strong chemical bond with nano pyrite, which enables to prevent the oxidation and photocorrosion of pyrite and promote the transfer of charge carriers. Low reagent doses of FeS2@GO catalyst (0.25 mg/L) and H2O2 (1.0 mM) were found to be efficient for removing 6-log of ARB and 7-log of extracellular ARG (e-ARG) after 30 and 7.5 min treatment, respectively, in synthetic wastewater. Bacterial regrowth was not observed even after a two-day incubation. Moreover, four recalcitrant MPs (sulfamethoxazole, carbamazepine, diclofenac, and mecoprop at an environmentally relevant concentration of 10 μg/L each) were completely removed after 10 min of treatment. The stable and recyclable composite generated more reactive species, including hydroxyl radicals (HO•), superoxide radicals (O2 • –), singlet oxygen (1O2). These findings highlight that the synthesized FeS2@GO catalyst is a promising heterogeneous photo-Fenton catalyst for the removal of emerging contaminants.
Antibiotic resistance is a major health concern globally and has been estimated to cause 10 million deaths worldwide by year 2050 if the current trend of inappropriate and excessive use of ...antibiotics continues. Although, the discovery of antibiotics has saved countless of lives for the past 80 years, increasing levels of bacterial resistance to antibiotics would jeopardize the progress in clinical and agricultural sectors and may cause life-threatening situations even for previously treatable bacterial infections. Antibiotic resistance would increase the levels of poverty of low-middle income countries mostly due to extended hospital stays, higher cost of treatment and untimely deaths that directly affect the total productivity rate. Recent incidences of antibiotic resistance have been gradually increasing globally and this may potentiate horizontal transmission of the resistant gene and have been linked with cross-resistance to other antibiotic families as well. This review summarizes the global burden of antibiotic resistance from the economic viewpoint, highlights the recent incidences of antibiotic resistance mainly related to Escherichia coli, Acinetobacter baumannii, Klebsiella pneumoniae, Salmonella spp. and Staphylococcus aureus, describes the common mechanistic actions of antibiotic resistance and potential strategies to overcome antibiotic resistance.
Display omitted
Antibiotic resistance poses a tremendous threat to human health. To overcome this problem, it is essential to know the mechanism of antibiotic resistance in antibiotic-producing and pathogenic ...bacteria. This paper deals with this problem from four points of view. First, the antibiotic resistance genes in producers are discussed related to their biosynthesis. Most resistance genes are present within the biosynthetic gene clusters, but some genes such as paromomycin acetyltransferases are located far outside the gene cluster. Second, when the antibiotic resistance genes in pathogens are compared with those in the producers, resistance mechanisms have dependency on antibiotic classes, and, in addition, new types of resistance mechanisms such as Eis aminoglycoside acetyltransferase and self-sacrifice proteins in enediyne antibiotics emerge in pathogens. Third, the relationships of the resistance genes between producers and pathogens are reevaluated at their amino acid sequence as well as nucleotide sequence levels. Pathogenic bacteria possess other resistance mechanisms than those in antibiotic producers. In addition, resistance mechanisms are little different between early stage of antibiotic use and the present time, e.g., β-lactam resistance in
. Lastly, guanine + cytosine (GC) barrier in gene transfer to pathogenic bacteria is considered. Now, the resistance genes constitute resistome composed of complicated mixture from divergent environments.
PDF
