Increase In Antibiotic-resistant Bacteria Research Articles

Photosensitizer-loaded hydrogels: A new antibacterial dressing.

Bacterial wound infection has emerged as a pivotal threat to human health worldwide, and the situation has worsened owing to the gradual increase in antibiotic-resistant bacteria caused by the improper use of antibiotics. To reduce the use of antibiotics and avoid the increase in antibiotic-resistant bacteria, researchers are increasingly paying attention to photodynamic therapy, which uses light to produce reactive oxygen species to kill bacteria. Treating bacteria-infected wounds by photodynamic therapy requires fixing the photosensitizer (PS) at the wound site and maintaining a certain level of wound humidity. Hydrogels are materials with a high water content and are well suited for fixing PSs at wound sites for antibacterial photodynamic therapy. Therefore, hydrogels are often loaded with PSs for treating bacteria-infected wounds via antibacterial photodynamic therapy. In this review, we systematically summarised the antibacterial mechanisms and applications of PS-loaded hydrogels for treating bacteria-infected wounds via photodynamic therapy. In addition, the recent studies and the research status progresses of novel antibacterial hydrogels are discussed. Finally, the challenges and future prospects of PS-loaded hydrogels are reviewed.

Design and application of histidine-functionalized ZnCr-LDH nanozyme for promoting bacteria-infected wound healing.

Excessive use of antibiotics can lead to an increase in antibiotic-resistant bacteria, which makes it a serious health threat. Therefore, developing new materials with antibacterial activity, such as nanozymes, has gained considerable attention. Reactive oxygen species (ROS) produced by nanozymes have rapid and effective antibacterial efficacy. Here, histidine (His) modified ZnCr layered double hydroxide (LDH) was synthesized inspired by the natural enzyme, and the enzyme-like activity of His/ZnCr-LDH was tested using a colorimetric method. Then, we developed an acid-enhanced antibacterial method based on the high peroxidase-like activity of His/ZnCr-LDH, and its ROS-generating capability in the presence of glucose oxidase (GOx) and glucose (Glu) as a source of hydrogen peroxide (H2O2). Gluconic acid (GA), the main product of the GOx reaction, provides an acidic environment and promotes ROS generation. The mentioned strategy shows high antibacterial activity at a low minimum inhibitory concentration (MIC) which represents the potential of His/ZnCr-LDH for effective bacterial elimination (3.5 μg mL-1 for S. aureus and 6 μg mL-1 for E. coli). In addition, animal experiments illustrated that the His/ZnCr-LDH can successfully boost the curing of infected wounds. The outcomes indicate that amino acid modified LDHs offer a new strategy for effective bacterial removal in different medical applications.

Cultivation of black soldier fly larvae in substrates containing antibiotics

The use of antibiotics in agriculture to treat and prevent infectious diseases and to stimulate growth results in antibiotics accumulating in animal tissues and wastes. Further utilization of such animal waste causes an increase in antibiotic-resistant bacteria. One of the promising ways of manure processing leading to reduction of antibiotic concentrations and obtaining useful biomass from organic waste may be bioconversion with the help of insects, particularly black soldier flies (Hermetia illucens) ( Diptera: Stratiomyldae). It is important to know how the presence of antibiotics in the feeding substrate affects the insects and their characteristics for further utilization. The effect of adding the antibiotics ceftriaxone, coliflox, levofloxacin and their mixtures to feed substrates on the growth of black soldier fly larvae was studied. When ceftriaxone, coliflox and levofloxacin were given at a concentration of 1–100 mg/kg feed, an increase in mean larval weight was observed compared to the control group after 5 days of culturing. At antibiotic concentrations of 500–1000 mg/kg, this effect was compensated, presumably by the negative effect of the antibiotic on the microbiota of the insect digestive system. At antibiotic concentrations of 2000 mg/kg feed, growth of Hermetia illucens larvae was retarded. No effect of antibiotics on fatty acid composition, moisture and ash content of insects was found. The results indicate that the use of black soldier fly for the treatment of animal waste is feasible, but the likely negative effect on insect growth at high antibiotic concentrations should be considered.

Facile bio-genic synthesis of Astragalus sarcocolla (Anzaroot) gum extract mediated silver nanoparticles: Characterizations, antimicrobial and antioxidant activities

The recent increase in antibiotic-resistant bacteria has led to a notable difficulty in medicine, demanding endeavors to fabricate efficient antibacterial substances. Unlike traditional physical and chemical approaches, bio-genic approaches demonstrate various advantages, such as affordability, safety, and speed. The current study presents novel green silver nanoparticles employing Astragalus sarcocolla (Anzaroot) gum extract (ASG-AgNPs). For the first time, the alcoholic gum extract of this plant was used to synthesize silver nanoparticles in order to obtain antioxidant and antimicrobial nanoparticles. After optimizing the fabrication reaction conditions, ASG-AgNPs were characterized by DLS, UV-Vis spectroscopy, TEM, FT-IR, and XRD analyses. The antibacterial and antifungal potential of ASG-AgNPs and ASG extract was examined against Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Enterococcus faecalis, and Candida albicans by the broth microdilution method. Also, the DPPH technique was carried out to investigate the antioxidant property. TEM images displayed a highly even and spherical configuration of ASG-AgNPs, with an average size of 15.76 ± 1.40 nm. ASG-AgNPs exhibited high antimicrobial activity against all examined microbial models. The strongest effects were on Candida albicans and Klebsiella pneumoniae microorganisms, with MIC values of 62.5 and 156.25 μg/ml, respectively. DPPH radical inhibition percentages were raised from 14 to 98 by raising the concentration of ASG-AgNPs from 100 to 800 μg/ml, indicating suitable antioxidant activity. Both the antimicrobial and antioxidant properties of the extract were weaker than ASG-AgNPs, suggesting significant synergism between the extract and AgNPs. These findings demonstrate that utilizing the gum of the Astragalus sarcocolla plant is effective in producing AgNPs, which likely possess significant potential for pharmaceutical and biomedical applications. However, further research is required.

Exopolysaccharide from Lactococcus hircilactis CH4 and Lactobacillus delbrueckii GRIPUMSK as new therapeutics to treat biofilm pathogens, oxidative stress and human colon adenocarcinoma

Naturally occurring biopolymers like exopolysaccharides (EPS) secreted by lactic acid bacteria (LAB) has gained significant attention as they are cost effective, renewable and safe. In order to prevent the rapid increase in antibiotic resistant bacteria, the EPS of LAB offers novel approach of targeting the antibiotic resistant pathogens by limiting their effects on environment. Accordingly, in this study, the production, purification, characterization and biological properties of exopolysaccharides from Lactococcus hircilactis strain CH4 and Lactobacillus delbrueckii strain GRIPUMSK were performed. The optimization of lactic acid bacterial strains for exopolysaccharide production was done by response surface methodology and changing the carbon sources in the growth media. The carbohydrate and protein of exopolysaccharide 1 were 79.7 % and 8.7 % respectively and exopolysaccharide 2 were 75.2 % and 9.3 % respectively. When compared with the commercial emulsifier sodium dodecyl sulfate, both the exopolysaccharides have shown good emulsifying activity. Both the exopolysaccharides were linear homo-polysaccharide as determined by Fourier transform infrared spectroscopy and Nuclear magnetic resonance spectra. Scanning electron microscopy showed that the exopolysaccharides were porous and capable of holding water. The exopolysaccharides were partially crystalline as confirmed by X-ray diffraction spectra. Exopolysaccharides from L. hircilactis and L. delbrueckii exhibited significant antimicrobial activity against H. pylori, S. flexneri, S. pyogenes, E. faecalis and C. albicans. Both the exopolysaccharides revealed significant 2,2-diphenyl-1-picrylhydrazyl and hydrogen peroxide scavenging ability with the IC50 value of 100 μg/ml and 80 μg/ml respectively. Exopolysaccharides from L. hircilactis and L. delbrueckii at 100 μg/ml showed significant anticancer activity on HT-29 cells with 58.4 % and 58.7 % respectively. These findings proved that exopolysaccharides from the two selected lactic acid bacterial strains could be explored as natural bioactive carbohydrate polymer for biomedical applications.

Analysis of antibiotic resistance genes in pig feces during the weaning transition using whole metagenome shotgun sequencing

Antibiotics have been used in livestock production for not only treatment but also for increasing the effectiveness of animal feed, aiding animal growth, and preventing infectious diseases at the time when immunity is lowered due to stress. South Korea and the EU are among the countries that have prohibited the use of antibiotics for growth promotion in order to prevent indiscriminate use of antibiotics, as previous studies have shown that it may lead to increase in cases of antibiotic-resistant bacteria. Therefore, this study evaluated the number of antibiotic resistance genes in piglets staging from pre-weaning to weaning. Fecal samples were collected from 8 piglets just prior to weaning (21 d of age) and again one week after weaning (28 d of age). Total DNA was extracted from the 200 mg of feces collected from the 8 piglets. Whole metagenome shotgun sequencing was carried out using the Illumina Hi-Seq 2000 platform and raw sequence data were imported to Metagenomics Rapid Annotation using Subsystem Technology (MG-RAST) pipeline for microbial functional analysis. The results of this study did not show an increase in antibiotic-resistant bacteria although confirmed an increase in antibiotic-resistant genes as the consequence of changes in diet and environment during the experiment.

Metal-Based Nanoparticles: Antibacterial Mechanisms and Biomedical Application.

The growing increase in antibiotic-resistant bacteria has led to the search for new antibacterial agents capable of overcoming the resistance problem. In recent years, nanoparticles (NPs) have been increasingly used to target bacteria as an alternative to antibiotics. The most promising nanomaterials for biomedical applications are metal and metal oxide NPs, due to their intrinsic antibacterial activity. Although NPs show interesting antibacterial properties, the mechanisms underlying their action are still poorly understood, limiting their use in clinical applications. In this review, an overview of the mechanisms underlying the antibacterial activity of metal and metal oxide NPs will be provided, relating their efficacy to: (i) bacterial strain; (ii) higher microbial organizations (biofilm); (iii) and physico-chemical properties of NPs. In addition, bacterial resistance strategies will be also discussed to better evaluate the feasibility of the different treatments adopted in the clinical safety fields. Finally, a wide analysis on recent biomedical applications of metal and metal oxide NPs with antibacterial activity will be provided.

Promising advances in nanobiotic-based formulations for drug specific targeting against multidrug-resistant microbes and biofilm-associated infections

Antimicrobial agents and alternative strategies to combat bacterial infections have become urgent due to the rapid development of multidrug-resistant bacteria caused by the misuse and overuse of antibiotics, as well as the ineffectiveness of antibiotics against difficult-to-treat infectious diseases. Nanobiotics is one of the strategies being explored to counter the increase in antibiotic-resistant bacteria. Nanobiotics are antibiotic molecules encapsulated in nanoparticles or artificially engineered pure antibiotics that are ≤ 100nm in size in at least one dimension. Formulation scientists recognize nanobiotic delivery systems as an effective strategy to overcome the limitations associated with conventional antibiotic therapy. This review highlights the general mechanisms by which nanobiotics can be used to target resistant microbes and biofilm-associated infections. We focus on the design elements, properties, characterization, and toxicity assessment of organic nanoparticles, inorganic nanoparticle and molecularly imprinted polymer-based nano-formulations that can be designed to improve the efficacy of nanobiotic formulation.

Air temperature and incidence of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae

BackgroundHigher outdoor temperature may be related to an increase in antibiotic resistant bacteria. We investigated the association between local outdoor air temperature and the incidence of extended-spectrum betalactamase (ESBL)-producing Enterobacteriaceae (ESBL-PE) correcting for known drivers of antibiotic resistance. MethodsWe performed a time-series regression study using prospectively collected weekly surveillance data on all ESBL-PE isolated from in- and outpatients of the University Hospital Basel, a tertiary care center in Switzerland, between 01/2008–12/2017. Temperature was measured hourly at the meteorological institute of the University Basel next to our institution over this time period. A time-series approach using a Poisson regression model and different lag terms for delayed exposure effects was performed to assess associations between minimal, mean and maximal weekly temperature and the number of ESBL-PE recovered. ResultsOver 10 years, recovery of ESBL-PE increased (annual incidence rate ratio [IRR] 1.14, 95%CI 1.13–1.16), while mean weekly temperature measures remained stable. In multivariable analyses, increasing temperature was associated with higher recovery rates of ESBL-PE after three to four weeks, correcting for potential confounders, such as the number of admissions, proportion of long-term nursing facility- and ICU-admissions, age, Charlson comorbidity index and consumption of antimicrobials (IRRs per 10 °C ranging from 1.14 to 1.22, 95%CIs 1.07–1.33). These trends remained when analyzing correlations between temperature with the proportion of extended spectrum cephalosporin resistance of all recovered Enterobacteriaceae. ConclusionsHigher outdoor temperature may be associated with an increase of ESBL-PE-incidence, independent of important confounders, such as antimicrobial consumption and thus should be considered for future resistance-trajectories.

Synthesis of Quinolones and Zwitterionic Quinolonate Derivatives with Broad-Spectrum Antibiotic Activity.

Quinolones are one of the most extensively used therapeutic families of antibiotics. However, the increase in antibiotic-resistant bacteria has rendered many of the available compounds useless. After applying our prediction model of activity against E. coli to a library of 1000 quinolones, two quinolones were selected to be synthesized. Additionally, a series of zwitterionic quinolonates were also synthesized. Quinolones and zwitterionic quinolonates were obtained by coupling the corresponding amine with reagent 1 in acetonitrile. Antibacterial activity was assessed using a microdilution method. All the compounds presented antibacterial activity, especially quinolones 2 and 3, selected by the prediction model, which had broad-spectrum activity. Furthermore, a new type of zwitterionic quinolonate with antibacterial activity was found. These compounds can lead to a new line of antimicrobials, as the structures, and, therefore, their properties, are easily adjustable in the amine in position 4 of the pyridine ring.

Use of Cocktail of Bacteriophage for Salmonella Typhimurium Control in Chicken Meat.

Foodborne diseases are extremely relevant and constitute an area of alert for public health authorities due to the high impact and number of people affected each year. The food industry has implemented microbiological control plans that ensure the quality and safety of its products; however, due to the high prevalence of foodborne diseases, the industry requires new microbiological control systems. One of the main causative agents of diseases transmitted by poultry meat is the bacterium Salmonella enterica. Disinfectants, antibiotics, and vaccines are used to control this pathogen. However, they have not been efficient in the total elimination of these bacteria, with numerous outbreaks caused by this bacterium observed today, in addition to the increase in antibiotic-resistant bacteria. The search for new technologies to reduce microbial contamination in the poultry industry continues to be a necessity and the use of lytic bacteriophages is one of the new solutions. In this study, 20 bacteriophages were isolated for Salmonella spp. obtained from natural environments and cocktails composed of five of them were designed, where three belonged to the Siphoviridae family and two to the Microviridae family. This cocktail was tested on chicken meat infected with Salmonella Typhimurium at 10 °C, where it was found that this cocktail was capable of decreasing 1.4 logarithmic units at 48 h compared to the control.

Identification of Antimicrobial Compounds in Two Streptomyces sp. Strains Isolated From Beehives.

The World Health Organization warns that the alarming increase in antibiotic resistant bacteria will lead to 2.7 million deaths annually due to the lack of effective antibiotic therapies. Clearly, there is an urgent need for short-term alternatives that help to alleviate these alarming figures. In this respect, the scientific community is exploring neglected ecological niches from which the prototypical antibiotic-producing bacteria Streptomycetes are expected to be present. Recent studies have reported that honeybees and their products carry Streptomyces species that possess strong antibacterial activity. In this study, we have investigated the antibiotic profile of two Streptomycetes strains that were isolated from beehives. One of the isolates is the strain Streptomyces albus AN1, which derives from pollen, and shows potent antimicrobial activity against Candida albicans. The other isolate is the strain Streptomyces griseoaurantiacus AD2, which was isolated from honey, and displays a broad range of antimicrobial activity against different Gram-positive bacteria, including pathogens such as Staphylococcus aureus and Enterococus faecalis. Cultures of S. griseoaurantiacus AD2 have the capacity to produce the antibacterial compounds undecylprodigiosin and manumycin, while those of S. albus AN1 accumulate antifungal compounds such as candicidins and antimycins. Furthermore, genome and dereplication analyses suggest that the number of putative bioactive metabolites produced by AD2 and AN1 is considerably high, including compounds with anti-microbial and anti-cancer properties. Our results postulate that beehives are a promising source for the discovery of novel bioactive compounds that might be of interest to the agri-food sector and healthcare pharmaceuticals.

Highly Efficient Adsorption and Removal of Amoxicillin from Aqueous Solution by Magnetic Graphene Oxide Nanocomposite

Background: Antibiotics have lasting effects on the environment. Among the properties of these substances are non-biodegradable, carcinogenic, high toxicity, and an increase in antibiotic-resistant bacteria. Therefore, they should be removed from aqueous solutions and the point of this think was to adsorb amoxicillin (AMO) by magnetic graphene oxide nanocomposite (MGO). Methods: The adsorption behavior of AMO was studied in a series of batch experiments as a function of pH (3-11), contact time (0-120 min), and AMO concentration (10-100 mg/L) different MGO dosages (0.1-1 g/L). The structures of MGO were confirmed by scanning electron microscope (SEM), and the X-ray diffraction (XRD). Results: The results revealed in optimized conditions (pH=3, contact time=75 min, AMO concentration= 10mg/L and adsorbent dose=0.75 g/L) maximum adsorption capacity and removal efficiency of AMO were 98.41 mg/g, respectively. The thermodynamical parameters showed that the sorption method was endothermal and spontaneous. Conclusion: MGO nanoparticles have extended capabilities such as easy and rapid separation from solution and high potential in removing AMO, so, it can be introduced as an appropriate adsorbent for removal of this antibiotics from water and wastewater.

A Novel Antimicrobial Peptide Sparanegtin Identified in Scylla paramamosain Showing Antimicrobial Activity and Immunoprotective Role In Vitro and Vivo.

The abuse of antibiotics in aquaculture and livestock no doubt has exacerbated the increase in antibiotic-resistant bacteria, which imposes serious threats to animal and human health. The exploration of substitutes for antibiotics from marine animals has become a promising area of research, and antimicrobial peptides (AMPs) are worth investigating and considering as potential alternatives to antibiotics. In the study, we identified a novel AMP gene from the mud crab Scylla paramamosain and named it Sparanegtin. Sparanegtin transcripts were most abundant in the testis of male crabs and significantly expressed with the challenge of lipopolysaccharide (LPS) or Vibrio alginolyticus. The recombinant Sparanegtin (rSparanegtin) was expressed in Escherichia coli and purified. rSparanegtin exhibited activity against Gram-positive and Gram-negative bacteria and had potent binding affinity with several polysaccharides. In addition, rSparanegtin exerted damaging activity on the cell walls and surfaces of P. aeruginosa with rougher and fragmented appearance. Interestingly, although rSparanegtin did not show activity against V. alginolyticus in vitro, it played an immunoprotective role in S. paramamosain and exerted an immunomodulatory effect by modulating several immune-related genes against V. alginolyticus infection through significantly reducing the bacterial load in the gills and hepatopancreas and increasing the survival rate of crabs.

Establishing recombinant production of pediocin PA-1 in Corynebacterium glutamicum

Bacteriocins are antimicrobial peptides produced by bacteria to inhibit competitors in their natural environments. Some of these peptides have emerged as commercial food preservatives and, due to the rapid increase in antibiotic resistant bacteria, are also discussed as interesting alternatives to antibiotics for therapeutic purposes. Currently, commercial bacteriocins are produced exclusively with natural producer organisms on complex substrates and are sold as semi-purified preparations or crude fermentates. To allow clinical application, efficacy of production and purity of the product need to be improved. This can be achieved by shifting production to recombinant microorganisms.Here, we identify Corynebacterium glutamicum as a suitable production host for the bacteriocin pediocin PA-1. C. glutamicum CR099 shows resistance to high concentrations of pediocin PA-1 and the bacteriocin was not inactivated when spiked into growing cultures of this bacterium. Recombinant C. glutamicum expressing a synthetic pedACDCgl operon releases a compound that has potent antimicrobial activity against Listeria monocytogenes and Listeria innocua and matches size and mass:charge ratio of commercial pediocin PA-1. Fermentations in shake flasks and bioreactors suggest that low levels of dissolved oxygen are favorable for production of pediocin. Under these conditions, however, reduced activity of the TCA cycle resulted in decreased availability of the important pediocin precursor l-asparagine suggesting options for further improvement. Overall, we demonstrate that C. glutamicum is a suitable host for recombinant production of bacteriocins of the pediocin family.

Horizontal Gene Transfer Is the Main Driver of Antimicrobial Resistance in Broiler Chicks Infected with Salmonella enterica Serovar Heidelberg.

ABSTRACTThe overuse and misuse of antibiotics in clinical settings and in food production have been linked to the increased prevalence and spread of antimicrobial resistance (AR). Consequently, public health and consumer concerns have resulted in a remarkable reduction in antibiotics used for food animal production. However, there are no data on the effectiveness of antibiotic removal in reducing AR shared through horizontal gene transfer (HGT). In this study, we used neonatal broiler chicks and Salmonella enterica serovar Heidelberg, a model food pathogen, to test if chicks raised antibiotic free harbor transferable AR. We challenged chicks with an antibiotic-susceptible S. Heidelberg strain using various routes of inoculation and determined if S. Heidelberg isolates recovered carried plasmids conferring AR. We used antimicrobial susceptibility testing and whole-genome sequencing (WGS) to show that chicks grown without antibiotics harbored an antimicrobial resistant S. Heidelberg population at 14 days after challenge and chicks challenged orally acquired AR at a higher rate than chicks inoculated via the cloaca. Using 16S rRNA gene sequencing, we found that S. Heidelberg infection perturbed the microbiota of broiler chicks, and we used metagenomics and WGS to confirm that a commensal Escherichia coli population was the main reservoir of an IncI1 plasmid acquired by S. Heidelberg. The carriage of this IncI1 plasmid posed no fitness cost to S. Heidelberg but increased its fitness when exposed to acidic pH in vitro. These results suggest that HGT of plasmids carrying AR shaped the evolution of S. Heidelberg and that antibiotic use reduction alone is insufficient to limit antibiotic resistance transfer from commensal bacteria to Salmonella enterica.IMPORTANCE The reported increase in antibiotic-resistant bacteria in humans has resulted in a major shift away from antibiotic use in food animal production. This shift has been driven by the assumption that removing antibiotics will select for antibiotic susceptible bacterial taxa, which in turn will allow the currently available antibiotic arsenal to be more effective. This change in practice has highlighted new questions that need to be answered to assess the effectiveness of antibiotic removal in reducing the spread of antibiotic resistance bacteria. This research demonstrates that antibiotic-susceptible Salmonella enterica serovar Heidelberg strains can acquire multidrug resistance from commensal bacteria present in the gut of neonatal broiler chicks, even in the absence of antibiotic selection. We demonstrate that exposure to acidic pH drove the horizontal transfer of antimicrobial resistance plasmids and suggest that simply removing antibiotics from food animal production might not be sufficient to limit the spread of antimicrobial resistance.

Air Temperature and Incidence of Extended-Spectrum Beta-Lactamase (ESBL)-Producing Enterobacteriaceae – An Observational Time-Series Regression Study

Background: Higher outdoor temperature may be related to an increase in antibiotic resistant bacteria. We investigated the association between outdoor air temperature and the incidence of extended-spectrum betalactamase (ESBL)-producing Enterobacteriaceae (ESBL-PE) correcting for known drivers of antibiotic resistance. Methods: We performed a time-series regression study using prospectively collected weekly surveillance data on all ESBL-PE isolated from in- and outpatients of the University Hospital Basel, a tertiary care center in Switzerland, between 01/2008-12/2017. Temperature was measured hourly at the meteorological institute of the University Basel next to our institution over this time period. A time-series approach using a Poisson regression model and different lag terms for delayed exposure effects was performed to assess associations between minimal, mean and maximal weekly temperature and the number of ESBL-PE recovered. Findings: Over 10 years, recovery of ESBL-PE increased (annual incidence rate ratio [IRR] 1·14, 95%CI 1·13-1·16), while mean weekly temperature measures remained stable. In multivariable analyses, increasing temperature was associated with higher recovery rates of ESBL-PE after three to four weeks, correcting for potential confounders, such as the number of admissions, proportion of long-term nursing facility- and ICU-admissions, age, Charlson comorbidity index and consumption of antimicrobials (IRRs per 10°C ranging from 1·14-1·22, 95%CIs 1·07-1·33). These trends remained when analyzing correlations between temperature with the proportion of extended spectrum cephalosporin resistance of all recovered Enterobacteriaceae. Interpretation: Higher outdoor temperature may be associated with an increase of ESBL-PE-incidence, independent of important confounders, such as antimicrobial consumption and thus should be considered for future resistance-trajectories. Funding Statement: This work was supported by the University Hospital Basel, Switzerland. No further funding was received for this study. Declaration of Interests: None of the authors has any conflict of interest related to this study. Ethics Approval Statement: This study was approved by the local ethics committee (Project-ID ID 2017-00100).

Do we need topical antibiotics for simple excision or the dressing after a skin wound?

We often use topical antibiotics for simple excisions or the skin after minor wounds. This is a long-standing practice to minimize scarring by preventing wound or surgical site infection to promote wound healing. Is this old practice the right way for today? Is there a scientific basis for it and can it persist? These questions are related to the increase in antibiotic-resistant bacteria in Korea. Currently, the guidelines for the use of oral antibiotics have been established and are being applied relatively well-controlled to prevent overuse and misuse, while discussions for evaluating the adequacy of the prophylactic use of topical antibiotics or establishing correct guidelines are lacking. Based on related research data, American Academy of Dermatology has been continuously campaigning against the abuse of prophylactic antibiotics by the public and doctors, following the increase in the abuse of topical antibiotics since 2013. Therefore, we discuss the necessity of using topical antibiotics for the prophylaxis based on literature evidence. Now is the time to make efforts to prevent the increase of antibiotic-resistant bacteria through the correct use and by reducing the prescription of topical antibiotics in Korea.

Postoperative Orthopedic Surgical Site Infection Antibiogram of dr. Soebandi Hospital, Jember in 2019

<span>Surgical site infection (SSI) is a microbial infection of the surgical wound within 30 days of operation or one year after surgery if an implant is placed in a patient. The incidence level of postoperative orthopedic SSI range to 71%. An increase in antibiotic-resistant bacteria causes the treatment of postoperative orthopedic surgical wound infections to be less effective, so there is an increase in morbidity, mortality, length of stay, and economic burden on hospital resources.</span><span lang="EN-ID">A</span><span lang="IN">ntibiogram</span><span lang="EN-ID"> were used to guide</span><span>the clinician and pharmacis</span><span lang="IN">t </span><span lang="EN-ID">selected</span><span>the best empiric antimicrobial treatment in the event of pending microbiology culture and susceptibility results</span><span lang="IN"> to overcome the disadvantages of antibotic-resistant bacteria</span><span>.</span><span> This study aimed to form a postoperative orthopedic SSI antibiogram of dr. Soebandi Hospital in</span><span lang="IN"> Jember City, East Java, Indonesia</span><span> which can be used as a reference to rational therapy</span><span lang="IN">. </span><span>This study used a descriptive observational study research design with medical records</span><span lang="IN"> from January – December 2019</span><span>.</span><span>A total of 34 isolates were found from 33 patients who did a culture examination. Of the 34 isolates, 25 were found to be positive for bacterial growth, while nine were negative. Twenty-two bacteria were Gram-negative and others were Gram-positive. The bacteria were tested against beta-lactam and non</span><span lang="IN">-</span><span>beta lactam antibiotics.</span><span>From antibiogram, showed that Gram-negative bacteria sensitive to the meropenem and resistant to cefotaxime. While, gram-positive bacteria showed sensitivity to doxycycline and resistant to erythromycin and penicillin.</span>

Presence of antibiotic resistance genes and its association with antibiotic occurrence in Dilúvio River in southern Brazil

It is known that antibiotics are widely used in human and veterinary medicine. In some countries the use is controlled, however few restrictions to their use are enforced in many countries. Antibiotics and their metabolites can reach the water bodies through sewage systems, especially in those countries with partial or absent wastewater treatment systems. The overuse and misuse of antibiotics has been linked with the increase of antibiotic resistant bacteria. The relation between the occurrence of antibiotics and resistance genes in surface waters has been widely studied worldwide evincing the great importance of this subject. In this work, a methodology for quantification of 40 antibiotics of 5 different classes, in river water, by SPE-LC-MS/MS was validated. Samples were taken during a two-year period from Dilúvio River, a stream that crosses the city of Porto Alegre (RS – Brazil) and receives in nature domestic effluent. The methodology met the requirements of validation, with Limit of Quantification varying from 20 ng L−1 to 100 ng L−1. A total of 48 samples was analyzed for the presence of antibiotics for two years. From the 40 antibiotics analyzed, 8 of them (Azithromycin, Cephalexin, ciprofloxacin, clindamycin, norfloxacin, sulfadiazine, sulfamethoxazole and trimethoprim) were present in all sampling points in the range of <LOQ to 344 ng L−1. The occurrence of antibiotics resistance genes in the sampling points was determined using qPCR. Specific primers were utilized to detected resistance genes to the β-lactam cephalexin (blaTEM gene), to the quilonones ciprofloxacin and norfloxacin (qnrS gene), to the macrolides azithromycin and clindamycin (ermB gene), and to the sulfonamides sulfadiazine and sulfamethoxazole (sulI gene), which were quantified the selected water samples. Quantitative PCR analysis revealed the presence of ARGs in all samples, with the highest concentration found for blaTEM.