Antimicrobial peptides (AMPs) are essential components of immune defenses of multicellular organisms and are currently in development as anti-infective drugs. AMPs have been classically assumed to ...have broad-spectrum activity and simple kinetics, but recent evidence suggests an unexpected degree of specificity and a high capacity for synergies. Deeper evaluation of the molecular evolution and population genetics of AMP genes reveals more evidence for adaptive maintenance of polymorphism in AMP genes than has previously been appreciated, as well as adaptive loss of AMP activity. AMPs exhibit pharmacodynamic properties that reduce the evolution of resistance in target microbes, and AMPs may synergize with one another and with conventional antibiotics. Both of these properties make AMPs attractive for translational applications. However, if AMPs are to be used clinically, it is crucial to understand their natural biology in order to lessen the risk of collateral harm and avoid the crisis of resistance now facing conventional antibiotics.
•The impact of fish farm on the structure of ARB and ARGs in river water was assess.•Culture-dependent survey revealed no significant differences in the abundance of ARB.•No significant differences ...in the frequency of tet genes were observed.•The fish farm’s impact on river water was manifested only by increased diversity of ARGs.
The aim of this study was to assess the impact of a fish farm on the structure of antibiotic resistant bacteria and antibiotic resistance genes in water of Drwęca River. Samples of upstream river waters; post-production waters and treated post-production waters from fish farm; as well as downstream river waters were monitored for tetracycline resistant bacteria, tetracycline resistant genes, basic physico-chemical parameters and tetracyclines concentration. The river waters was characterized by low levels of pollution, which was determined based on water temperature, pH and concentrations of dissolved oxygen and tetracycline antibiotics. Culture-dependent (heterotrophic plate counts, counts of bacteria resistant to oxytetracycline (OTCR) and doxycycline (DOXR), minimum inhibitory concentrations for oxytetracycline and doxycycline, multidrug resistance of OTCR and DOXR, qualitative composition of OTCR and DOXR, prevalence of tet genes in resistant isolates) and culture-independent surveys (quantity of tet gene copies) revealed no significant differences in the abundance of antibiotic-resistant bacteria and antibiotic resistance genes between the studied samples. The only way in which the fish farm influenced water quality in the Drwęca River was by increasing the diversity of tetracycline-resistance genes. However, it should also be noted that the bacteria of the genera Aeromonas sp. and Acinetobacter sp. were able to transfer 6 out of 13 tested tet genes into Escherichiacoli, which can promote the spread of antibiotic resistance in the environment.
Background Antibiotics are miracles of science and critical for many surgical procedures. However, the emergence of multidrug resistant pathogens resulting from inappropriate antibiotic use is a ...threat to modern medicine. This study aimed to determine the appropriateness of antibiotic use, cost, consumption and impact of an antibiotic stewardship intervention round in a surgical ward setting. Methods Baseline antibiotic utilisation was determined with a retrospective cross-sectional study in two surgical wards in a tertiary academic hospital in South Africa where medical records of 264 patients who received antibiotics were reviewed. In the second stage of the study, records of 212 patients who received antibiotics were reviewed during a weekly antibiotic stewardship intervention round. The volume of antibiotics consumed was determined using defined daily doses (DDDs)/1000 patients' days, and the appropriateness of the antibiotic prescription for treatment was also determined using a quality-of-use algorithm. Results There was a reduction in the volume of antibiotic consumption from a total 739.30 DDDs/1000 to 564.93 DDDs/1000 patient days, with reduction in inappropriate antibiotic use from 35% to 26% from baseline to antibiotic stewardship programme stages, respectively. There was an overall increase in culture targeted therapy in both wards in the antibiotic stewardship programme stage. Conclusion The implementation of an antibiotic stewardship programme led to a reduction in antibiotic consumption and improvement in appropriate use of antibiotics.
Antibiotic resistance (AR) is extensively present in various environments, posing emerging threat to public and environmental health. Landfill receives unused and unwanted antibiotics through ...household waste and AR within waste (e.g., activated sludge and illegal clinical waste) and is supposed to serve as an important AR reservoir. In this study, we used culture-dependent methods and quantitative molecular techniques to detect and quantify antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) in 12 landfill leachate samples from six geographic different landfills, China. Five tested ARGs (
tetO
,
tetW
,
bla
TEM
,
sulI
, and
sulII
) and seven kinds of antibiotic-resistant heterotrophic ARB were extensively detected in all samples, demonstrating their occurrence in landfill. The detected high ratio (10
−2
to 10
−5
) of ARGs to 16S ribosomal RNA (rRNA) gene copies implied that ARGs are prevalent in landfill. Correlation analysis showed that ARGs (
tetO
,
tetW
,
sulI
, and
sulII
) significantly correlated to ambient bacterial 16S rRNA gene copies, suggesting that the abundance of bacteria in landfill leachate may play an important role in the horizontal spread of ARGs.
The major concern regarding the biocide triclosan (TCS) stems from its potential coselection for antibiotic resistance. However, environmental impacts are often investigated using high concentrations ...and acute exposure, while predicted releases are typified by chronic low concentrations. Moreover, little information is available regarding the reversibility of TCS and derived antibiotic resistance with diminishing TCS usage. Here, the model Gram-negative bacterium Escherichia coli was exposed to 0.01 mg/L TCS continuously for more than 100 generations. The adapted cells gained considerable resistance to TCS as indicated by a significant increase in the minimal inhibitory concentration (MIC50) from 0.034 to 0.581 mg/L. This adaptive evolution was attributed to overexpression and mutation of target genes (i.e., fabI) as evidenced by transcriptomic and genomic analyses. However, only mild tolerance to various antibiotics was observed, possibly due to reduced membrane permeability and biofilm formation. After TCS exposure ceased, the adapted cells showed persistent resistance to TCS due to inheritable genetic mutations, whereas their antibiotic tolerance declined over time. Our results suggest that extensive use of TCS may promote the evolution and persistence of TCS-resistant bacterial pathogens. A quantitative definition of the conditions under which TCS selects for multidrug resistance in the environment is crucially needed.
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•Four pilot-scale CWs differing in plant species and planting patterns were compared.•Nutrients, antibiotics and ARGs in aquaculture wastewater were efficiently removed.•Microbial ...structure and diversity spatially differed in four CWs.•Treatment performances of CWs attributed to the plant physiological features.
Four horizontal subsurface flow pilot-scale constructed wetlands (CWs) named as S1, S2, M1 and M2 were constructed to treat aquaculture wastewater. And two different plant species (Iris pseudacorus and Phragmites australis) were cultivated in single and mixed planting patterns in these four CWs. The removal rate of conventional pollutants (nutrient and organic compounds), antibiotics including enrofloxacin (ENR), sulfamethoxazole (SMZ), and antibiotic resistance genes (ARGs) were evaluated among those CWs. The total nitrogen and NH4+–N removal rates of all CWs were 73.24%–91.46% and 61.20%–92.27%, respectively. CWs with mixed planting patterns, such as M1 (planted with Iris pseudacorus at the forepart and Phragmites australis at the back) and M2 (alternate cultivation with Iris pseudacorus and Phragmites australis) showed better performances than CWs planted with single plant species, such as S1 (Iris pseudacorus) and S2 (Phragmites australis). However, S1 and S2 exhibited higher removal efficiencies for emerging contaminants: S1 had removal efficiencies of 77.64%, 68.70%, and 58.21% for ENR, SMZ, and total ARGs, respectively, and S2 had removal efficiencies of 81.11%, 64.94%, and 56.26% for ENR, SMZ, and total ARGs, respectively. Compared with single planting, the dominant genera in mixed planting exhibited lower relative abundance in anaerobes and higher percent of bacteria associated with nitrogen metabolism, indicating that different plant physiological characteristics affected the microbial community structures of the CWs.
Summary Effective antimicrobials play an important element in modern medicine’s success in treating infections, without which the patients would be put at risk. Along with the naturally occurring ...process of antibiotic resistance, the misuse/overuse of these antibiotics also leads to them losing their effectiveness. It limits the treatment options as the microbe that had previously been sensitive becomes resistant. This bibliometric study was performed by searching the Scopus database according to a specific search strategy. A total of 4200 articles were retrieved from the search, and after applying inclusion and exclusion criteria, 1355 articles were included in the study. All of the bibliometric variables examined in this study revealed significant growth in this research field, especially during COVID-19, in terms of increasing scientific output and research collaboration. The study findings indicate an adequate quality and amount of antimicrobial resistance (AMR) research on microbiology and pharmacodynamics in India, whereas more research needs to be conducted on measures to tackle AMR, its public health, and policy aspects.
Antibiotic resistance genes (ARGs) in the endophytes of vegetables represent a potential route of human exposure to the soil resistome. However, the effect of vegetable species on the endophytic ARG ...profiles is unclear, hampering our understanding of how ARGs migrate into the soil-vegetable system and their potential health risks. Here, we planted four leafy vegetables (cilantro, endive, lettuce, and pak choi), which are commonly eaten raw, and analyzed the resistomes and microbiomes in three sample types (rhizosphere soil, root, and leaf endophytes). A total of 150 ARG subtypes were detected using high-throughput quantitative PCR. Vegetable species had a significant effect on ARG diversity and abundance, and pak choi accumulated more ARGs in its associated microbiome than the other three vegetables. The bacterial community was the primary factor shaping ARG profiles and was significantly correlated with ARG subtypes. We identified aadE, tet(34), and vanSB as shared ARGs among leaves of the four vegetables; the bacterial families correlated with tet(34) and vanSB were also shared across the vegetables and belonged to Proteobacteria. This study deepens our understanding of how endophytic ARG profiles vary among different vegetables and highlights the potential health risk associated with consuming these vegetables raw.
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•Antibiotic resistance genes (ARGs) are examined in four vegetable microbiomes.•Vegetable species significantly affect ARG diversity and abundance.•Lettuce and pak choi leaves harbor more abundant ARGs than cilantro or endive.•The ARGs, aadE, tet(34), and vanSB, are shared across all four vegetable leaves.•Burkholderiaceae is markedly correlated with ARGs, tet(34) and vanSB.
is a well-known pathogen that is highly prevalent in the world population, and
infection is potentially hazardous to humans because of its relationship to various gastrointestinal diseases, such as ...gastric ulcers, chronic gastritis, and gastric carcinoma. Therefore, the clinical guidelines recommend taking antibiotic therapy to eradicate the pathogen, which usually leads to the desired therapeutic effect. However, some failure cases of this therapy indicate that the increasing antibiotic resistance and side effects may affect the therapeutic effect. Here we propose that using probiotics as supplementation for antibiotic therapy may provide an extra help. Recent studies have shown that probiotic supplementation therapy has promising application prospects; it can enhance the antibiotic effect to achieve a better therapeutic result and maintain the balance of the host gastrointestinal microbiota. In summary, under global conditions of increasing
prevalence, probiotic supplementation therapy is worthy of further studies for future clinical application.
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