Problem Of Antimicrobial Resistance Research Articles

Prevalence of multidrug-, extensively drug-, and pandrug-resistant bacteria in clinical isolates from King Khaled Hospital, Najran, Saudi Arabia

Abstract Background Saudi Arabia faces a growing antimicrobial resistance (AMR) problem, exacerbated by the widespread use of antibiotics in clinical and agricultural settings. Despite this, AMR surveillance has been limited, particularly in regions like Najran, making this study critical for informing local and national public health strategies. Aim This study explored the prevalence of multidrug-resistant, extensively drug-resistant, and Pandrug-resistant bacteria in Najran, Saudi Arabia. Study design This is a cross-sectional study. Methods This study included 559 diverse clinical samples (urine, wound, etc.) collected from various departments in King Khaled Hospital, Saudi Arabia. The Phoenix BD instrument was used for complete bacterial identification and antibiotic sensitivity testing. Demographic and clinical data were analyzed statistically. Results Of the 559 samples, the culture positivity rates were as follows: 51% for Escherichia coli, 22% for Staphylococcus aureus, 14% for Klebsiella pneumoniae, 6% for Acinetobacter baumannii, 6% for Pseudomonas aeruginosa, and 1% for Enterococcus faecium. Majority of the cases were from male (57%), and age 50+ (59%) recorded highest cases. Participants from outpatient department (OPD) ward recorded the highest (56%) cases, while urine sample recorded the highest (49%) cases. About 84% of the isolates were multidrug‑resistance (MDR), 10% were extensively drug‑resistance (XDR), and 6% pandrug‑resistance (PDR). Our analysis showed high sensitivity to Oxazolidonone, Tetracycline, carbapenems, Lipopeptide, Aminoglycopeptide classes of antibiotics. Conclusions The study revealed a high prevalence of drug resistance, highlighting the critical importance of continued surveillance and research to mitigate the spread of antimicrobial resistance and preserve the effectiveness of existing therapies.

Pyrazole Amides Towards Trailblazing Antimicrobial Research: Bridging in Vivo Insights and Molecular Docking Studies

Antimicrobial resistance presents a significant threat to contemporary healthcare systems, making it increasingly difficult to treat infections that were once easily managed. This study aims to assess the efficacy of pyrazole benzamide derivatives (M5a–M5o), which were synthesized for their antimicrobial and antifungal activities. These compounds were tested against methicillin resistant staphylococcus aureus (MRSA), vancomycin resistant staphylococcus aureus (VRSA), mycobacterium tuberculosis H37Rv and other resistant species. The minimum inhibitory concentrations (MIC) were determined using standardized protocols to evaluate their potency and effectiveness. Molecular docking studies were also conducted to explore potential interactions and binding affinities at the molecular level, providing further insights into their antimicrobial and anti-tubercular mechanisms. Compounds M5i, M5k, and M5b emerged as the most potent, displaying MIC value of 3.12 μg/ml. These compounds show great potential as new agents in addressing the growing problem of antimicrobial resistance. Molecular docking studies against Enoyl-[acyl-carrier-protein] reductase (4DRE), revealed key interactions, with compound M5n showing a docking energy of -9.8 kcal/mol and compound M5g at -9.6 kcal/mol. These compounds formed important hydrogen bonds and π-interactions with residues like Lys165, Gly14, Ser94, and Ile21. Overall, the findings indicate that specific pyrazole-benzamide derivatives exhibit promising antimicrobial and antifungal activities, underscoring their potential as therapeutic agents. Additionally, the integration of molecular docking studies proves valuable in guiding the development and optimization of these compounds for future therapeutic applications.

Antibiotics Knowledge and Prescription Patterns Among Dental Practitioners in Croatia, Bosnia and Herzegovina, and Serbia: A Comparative E-Survey with a Focus on Medically Healthy and Compromised Patients

Background: The non-specific prescription of antibiotics, especially in dentistry, contributes to the global problem of antimicrobial resistance and highlights the need for education on the proper use and serious consequences of overprescribing these drugs. The main objective of this study is to assess and evaluate antibiotic knowledge and prescribing patterns in dental practice in Croatia, Bosnia and Herzegovina, and Serbia, focusing on understanding the rationale for prescribing, adherence to evidence-based guidelines, and dentists’ awareness of antibiotic resistance. Methods: A total of 795 dentists participated in this electronic cross-sectional survey (Croatia N = 336, Bosnia and Herzegovina N = 176, and Serbia N = 283). The study utilized a self-structured questionnaire to collect data on various aspects of antibiotic use, including knowledge, prescribing practices, awareness of guidelines, and demographic and professional information about dentists. Data analysis included the Mann–Whitney test, the Kruskal–Wallis test with post hoc analysis, and chi-square tests, with statistical significance set at p < 0.05. Results: The overall score for the participants’ knowledge of antibiotics was 6.40 ± 1.40 out of a maximum of eight points, which indicates a generally good level of knowledge among dentists. Factors such as gender, specialty, and practice location significantly influenced the level of knowledge (p < 0.05). However, actual prescribing practice was a cause for concern. Only 66.1% of Croatian dentists felt they had received adequate training during their studies, and even fewer in Serbia (48.4%) and Bosnia (46.6%). It is noteworthy that 9.7% of dentists in Bosnia and Herzegovina prescribe antibiotics at the request of patients, while 22.3% of Croatian and 25.4% of Serbian dentists do so. Many dentists prescribe no or only one antibiotic per week. In addition, 50.9% of Croatian dentists reported adverse effects related to the use of antibiotics, while only 31.3% of Bosnian and 33.6% of Serbian dentists reported similar experiences. Conclusions: While the study results indicate that dentists in the region generally possess good knowledge of antibiotic use, there are significant discrepancies between this knowledge and actual prescribing practices. This highlights the need for enhanced educational programs and awareness initiatives focused on proper antibiotic guidelines to improve prescribing behaviors.

Cultures of Activity, Cultivating Resistance.

The problem of antimicrobial resistance (AMR) is often viewed through biomedical and/or behavioral lenses, with the underlying economic principles and "headwinds" shaping resistance less visible. In this paper, we focus on how healthcare funding models structure the ways AMR is perceived and addressed as an institutional priority. Specifically, we explore how activity-based funding reflects and operationalizes ingrained assumptions about what is valuable and/or worthwhile within the organizational ecology of the hospital. Drawing on interviews with 36 executives from several hospital clinical care settings across two Australian states, we illuminate the ways the activity-based funding paradigm works against efforts to combat AMR. Concerningly, we further observe how activity-based funding models can inadvertently position rising rates of resistance as a benefit-at least in the short term-as the new and intensified interventions required to address resistant infections require more "activity" and thus deliver higher reimbursement at the level of annualized budgets. In failing to recognize the (social and economic) value of reduced activity, activity-based funding risks contributing to AMR, rather than working to resolve it.

Quinolone and Tetracycline-Resistant Biofilm-Forming Escherichia coli Isolates from Slovak Broiler Chicken Farms and Chicken Meat

Escherichia coli isolates from intensive poultry production are associated with antimicrobial resistance and worldwide health problems. The aim of the study was to detect and evaluate the phenotypic and genotypic antimicrobial resistance, biofilm formation, phylogenetic typing, and virulence factors in E. coli isolates from the rectal swabs of chickens from two farms and swabs of chicken meat purchased from Slovakian food markets. Interpretative readings of minimal inhibitory concentration (MIC) revealed dominant resistance to ampicillin (>50%) in both groups. We also detected higher resistance to ciprofloxacin (45%), tetracycline, ampicillin + sulbactam, and trimethoprim + sulfonamide (each >30%). Here, 28.57% of the strains studied were multidrug-resistant (MDR). The formation of weak biofilms was confirmed in 8.8% of E. coli, while one of the strains obtained from chicken cloacal swabs was classified as a strong biofilm producer. The most frequently confirmed phylogenetic groups in E. coli were B1 and A1 in all groups. PCR detection revealed the presence of genes encoding tetracycline resistance (tetAB) and plasmid-mediated quinolone resistance (qnrABS), and Int1 (52.9%), Tn3 (76.5%), kpsMT II (8.8%), fimA (97.1%), cvaC (38.2%), and iutA (76.5%) genes in the strains studied. Our results demonstrate that chickens and chicken meat were the source of antibiotic-resistant, biofilm-forming, and virulent E. coli, representing a potential risk from the point of view of the One Health concept.

Antibiofilm activities of lactoferricin-related Trp- and Arg-rich antimicrobial hexapeptides against pathogenic Staphylococcus aureus and Pseudomonas aeruginosa strains.

Recently, several antimicrobial peptides (AMPs) varying in length from 12 to 37 residues, have been shown to act as antibiofilm agents. Here we report a study of twenty-three hexapeptides modeled after four different Trp- and Arg-rich AMPs, including the RRWQWR-NH2 peptide, derived from bovine lactoferrin. They were tested against the pathogenic Gram-negative Pseudomonas aeruginosa PAO1 strain and a Gram-positive Staphylococcus aureus MRSA strain. Both strains were engineered to express the GFP protein, and fluorescence detection was used to measure the ability of the peptides to prevent biofilm formation (MBIC) or to cause the breakdown of established biofilms (MBEC). Similar antibiofilm activities were obtained with the standard crystal violet dye assay. Most Trp- and Arg-rich hexapeptides displayed a potent antibiofilm activity against the Gram-positive S. aureus MRSA strain. In particular, hexapeptides with 3 Arg and 3 Trp were very effective, especially when they contained the three Trp in sequence. Somewhat unexpectedly, the antimicrobial (MIC) values correlated with the MBIC and MBEC values, which has not been seen for some other AMP/antibiofilm peptides. Our results demonstrate that short Trp- and Arg-rich peptides merit further studies as antibiofilm agents, that could be deployed to address part of the antimicrobial resistance problem.

Enhancing Antimicrobial Peptide Activity through Modifications of Charge, Hydrophobicity, and Structure.

Antimicrobial peptides (AMPs) are emerging as a promising alternative to traditional antibiotics due to their ability to disturb bacterial membranes and/or their intracellular processes, offering a potential solution to the growing problem of antimicrobial resistance. AMP effectiveness is governed by factors such as net charge, hydrophobicity, and the ability to form amphipathic secondary structures. When properly balanced, these characteristics enable AMPs to selectively target bacterial membranes while sparing eukaryotic cells. This review focuses on the roles of positive charge, hydrophobicity, and structure in influencing AMP activity and toxicity, and explores strategies to optimize them for enhanced therapeutic potential. We highlight the delicate balance between these properties and how various modifications, including amino acid substitutions, peptide tagging, or lipid conjugation, can either enhance or impair AMP performance. Notably, an increase in these parameters does not always yield the best results; sometimes, a slight reduction in charge, hydrophobicity, or structural stability improves the overall AMP therapeutic potential. Understanding these complex interactions is key to developing AMPs with greater antimicrobial activity and reduced toxicity, making them viable candidates in the fight against antibiotic-resistant bacteria.

Knowledge and practice regarding antibiotic use among poultry farmers in Abia State, Nigeria

This study was conducted to determine factors that influence choice and application of antibiotics by broiler farmers in Abia State-Nigeria by administration of structured questionnaires to 110 farms. All 66 poultry farms that responded to questionnaires administered to them accepted that they use antibiotics on their farms. 67% of the farmers in Abia State were males, with first degree (41%), small-scale farmers (53%) and keeping broilers (74.2%) in deep litter system (77.3%). They said that drugs they use to treat their birds are prescribed by Veterinary Doctors (76.4%). Drug-formulations containing tetracycline (90%) are the ones most of the farmers used on their birds. 70.4% of the farmers had good knowledge of laws regulating use of antibiotics in raising food animals. They are also aware of the problem of Antimicrobial resistance.

Phenotypic and genotypic characterization of antimicrobial resistance in Enterococcus species from dairy niches

The present work was carried out to investigate the prevalence of antimicrobial resistance (AMR) in dairy enterococci. Dairy samples comprising of raw milk and traditionally fermented milks were collected from local surrounding areas and a total of 140 enterococci strains were isolated from the dairy samples and further, 104 isolates were tested for antimicrobial susceptibility. The most prevalent resistance was observed against cephalosporins followed by fosfomycin, rifampicin, erythromycin etc. Multi-antibiotic resistance index of the tested isolates ranged from 0.09 to 0.36. Minimum inhibitory concentration testing showed very high cut-offs against erythromycin, tetracycline, cefepime and cefotaxime in certain isolates. Further, Extended Spectrum β-lactamase (ESBL) production tested by double disc synergy method confirmed 9 isolates as ESBL positive along with the presence of blaTEM gene in certain isolates. In addition, AMR genes against aminoglycoside, tetracyclines, macrolides, chloramphenicol along with multi-drug transporter gene (emeA) was also detected in many isolates. The resistant enterococci isolates also showed a high frequency of the presence of mobile genetic elements viz. Transposons (Tn-5397 and Tn-916/Tn-1545 family) and Integrons (intI1, intI3). Finally, virulence traits such as gelatinase and hemolysin production along with gelE and cylA genes was also detected in many of the resistant enterococci isolates. Although, the virulence traits could not be directly correlated with the AMR resistance of the isolates, the results from the study demonstrated the wide prevalence of AMR in dairy enterococci that could greatly contribute to the problem of antimicrobial resistance in the food chain.

Antibacterial effects of human mesenchymal stem cells and their derivatives: a systematic review.

The growing problem of antimicrobial resistance (AMR) poses a significant challenge to public health; This is partly due to the lack of advancements in the development of novel antibiotics and the pressing need for alternative treatment options. Mesenchymal stem cells (MSC) possess secretory components that enhance the immune response and peptides that disrupt the bacteria constitution. The isolation of various human tissues has facilitated the investigation of the diverse potentials of MSC and their components. Further research is needed to fully understand the spectrum and efficacy of these elements and their differences. The primary aim of this study was to perform a thorough review of the current literature related to the antimicrobial properties of MSC and their associated components. The objective was to establish an insight into the results and effects of utilizing MSC in relation to bacterial colonization, and to present an overview of previously documented findings. This systematic literature review was conducted using the PubMed, Embase, and Web of Science databases. Data on the effect of MSC or their derivatives were measured by calculating the percentage of bacterial counts reduction after treatment with MSC in comparison to the control. A total of 3,911 articles were screened, and 31 eligible publications were selected for inclusion in the analysis. In the current systematic review, the majority of the experimental designs showed positive outcomes in terms of bacterial load reduction when MSC or their derivatives were used, with bone marrow being the most effective tissue. The rest of the findings exhibited heterogeneity in the spectrum of outcomes that could be attributed to the effects of using various tissues derived MSC in both in vivo and in vitro studies. The findings of our study indicate the potential antibacterial characteristics of MSC. The direct antimicrobial activity of these cells was demonstrated by our results, which quantitatively showed a decrease in bacterial growth after treatment with MSC. However, additional research is required to clarify the factors that determine the efficacy of their antimicrobial activity and their various components.

Treatment of avian pathogenic Escherichia coli infected broilers with aqueous extracts of Vernonia amygdalina in a challenge experiment

Colibacillosis, which is the leading cause of infectious diseases resulting in mortality and economic losses in poultry is triggered by Avian pathogenic Escherichia coli (APEC). Conventionally, antibiotic growth promoters (AGP) are incorporated into poultry diets to control infectious diseases and boost performance. However, because of the problem of antimicrobial resistance, synthetic antibiotics are now restricted or banned in animal production in some countries. In this study, we carried out a challenge experiment by inoculating healthy broilers with APEC (106 cfu/mL) by oral gavage on day 21 of the experiment and orally administering various treatments five days post challenge for five days; synthetic antibiotics (T2), Vernonia amygdalina (bitter leaf) extracts (T3), no treatment (T4), which were compared with the control that wasn’t challenged (T1). The experiment lasted for 42 days. Performance, hematological and histological studies were carried out. The results show that the challenged birds became diseased with the development of visible lesions, which ameliorated over time to varying extents with the use of synthetic antibiotics and Vernonia treatments. Overall, the performance of the birds with the use of Vernonia (T3) was comparable with that of synthetic antibiotics (T2) without eliciting any adverse hematological effects on the broilers. We therefore conclude that Vernonia can be safely used as a supplement for disease prevention in broiler chicken production

The Influence of Silver-Containing Bionanomaterials Based on Humic Ligands on Biofilm Formation in Opportunistic Pathogens.

The uncontrolled use of antibiotics has led to a global problem of antimicrobial resistance. One of the main mechanisms of bacterial resistance is the formation of biofilms. In order to prevent the growth of antimicrobial resistance, it is crucial to develop new antibacterial agents that are capable of inhibiting the formation of biofilms. This makes this area of research highly relevant today. Promising candidates for these antibacterial agents are new bionanomaterials made from natural humic substances and silver nanoparticles. These substances have the potential to not only directly kill microorganisms but also penetrate biofilms and inhibit their formation. The goal of this study is to synthesize active pharmaceutical substances in the form of bionanomaterials, using ultradispersed silver nanoparticles in a matrix of coal humic substances, perform their characterization (NMR spectroscopy, TEM, and ICP-AES methods), and research their influence on biofilm formation in the most dangerous opportunistic pathogens (E. coli, Methicillin-resistant St. Aureus, K. pneumoniae, P. aeruginosa, St. aureus, A. baumannii, and K. Pneumonia). The results showed that all of the studied bionanomaterials had antibacterial activity against all of the opportunistic pathogens. Furthermore, they were found to have a suppressive effect on both pre-existing biofilms of these bacteria and their formation.

Effect of feeding chitosan and blend of essential organic acids on growth performance, haematological parameters and innate immunity in early aged male layer chicks.

The use of antibiotics as conventional feed additives in poultry operations have proven useful, however resulted serious health concerns to consumer due to their bio-accumulation, besides rising problem of antimicrobial resistance in microbes, thus, an alternative to antibiotic growth promoter have called for. One of the aim of the experiment was to assess the lone and combined effects of feeding of chitosan oligosaccharide (COS) and blend of organic acids and short chain fatty acids in essential oils on growth performance, haematological parameters, relative lymphoid organ weight and innate immunity in early aged layer chick(male birds). A total of ninety, day-old chicks were randomly allotted into five groups: CO, Control group fed only poultry feed ; AGP, antibiotic growth promoter fed Avilomycin at the dose of 200mg/kg of poultry feed; CH, chitosan oligosaccharide fed at the rate of 100mg/kg feed; OE, blend of organic acids and short chain fatty acids in essential oils contained 1000 to 2000mg/kg feed in a graded dose per week and CH + OE, chitosan oligosaccharide plus blend of organic acids and short chain fatty acids in essential oils at consistent rate and manner as followed for each of given feed additives when fed individually. Data on growth performance, samples for haematological parameters and innate immunity were measured and assayed on 7th, 21st and 42nd day post feeding (dpf) respectively. The results showed that compared with the control group; there is a marginal gain in body weight at 7th and 21st dpf in CH group and the corresponding CH + OE group. Feed conversion ratio in CH group was remarkably good at 7th and 21st dpf. No significant difference was observed in relative organ weights of thymus, spleen and Bursa of Fabricius in treatment groups as compared to control birds; however a significant rise in splenic weight index in OE fed birds at 42nd dpf noted. Haematological changes were inconsequential in treatment groups with an exception to enhancement of heterophil to lymphocyte ratio (H:L ratio) in CH group at 42nd dpf. Serum lysozyme activity proportionately elevated in CH + OE group on 21st and 42nd dpf when measured against control group; on the other hand no detectable augmentation of gut lysozyme activity observed. Both serum bactericidal and gut bactericidal activity boosted in combinatorial group at 42nd dpf. These results indicated that early age feeding of chitosan individually or combination with organic acids and short chain fatty acids in layer chick is beneficial, as it has the potential to enhance body weight gain to some extent and improves systemic and localized innate immunity to offer protection against infectious assaults thus may avoid early chick mortality in farms.

Mixed-charge hyperbranched polymer nanoparticles with selective antibacterial action for fighting antimicrobial resistance

The escalating menace of antimicrobial resistance (AMR) presents a profound global threat to life and assets. However, the incapacity of metal ions/reactive oxygen species (ROS) or the indiscriminate intrinsic interaction of cationic groups to distinguish between bacteria and mammalian cells undermines the essential selectivity required in these nanomaterials for an ideal antimicrobial agent. Hence, we devised and synthesized a range of biocompatible mixed-charge hyperbranched polymer nanoparticles (MCHPNs) incorporating cationic, anionic, and neutral alkyl groups to effectively combat multidrug-resistant bacteria and mitigate AMR. This outcome stemmed from the structural, antibacterial activity, and biocompatibility analysis of seven MCHPNs, among which MCHPN7, with a ratio of cationic groups, anionic groups, and long alkyl chains at 27:59:14, emerged as the lead candidate. Importantly, owing to inherent differences in membrane potential among diverse species, alongside its nano-size (6 - 15 nm) and high hydrophilicity (Kow = 0.04), MCHPN7 exhibited exceptional selective bactericidal effects over mammalian cells (selectivity index > 564) in vitro and in vivo. By inducing physical membrane disruption, MCHPN7 effectively eradicated antibiotic-resistant bacteria and significantly delayed the emergence of bacterial resistance. Utilized as a coating, MCHPN7 endowed initially inert surfaces with the ability to impede biofilm formation and mitigate infection-related immune responses in mouse models. This research heralds the advent of biocompatible polymer nanoparticles and harbors significant implications in our ongoing combat against AMR. Statement of SignificanceThe escalating prevalence of antimicrobial resistance (AMR) has been acknowledged as one of the most significant threats to global health.Therefore, a series of mixed-charge hyperbranched polymer nanoparticles (MCHPNs) with selective antibacterial action were designed and synthesized. Owing to inherent differences in membrane potential among diverse species and high hydrophilicity (Kow = 0.04), the optimal nanoparticles exhibited exceptional selective bactericidal effects over mammalian cells (selectivity index >564) and significantly delayed the emergence of bacterial resistance. Importantly, they endowed surfaces with the ability to impede biofilm formation and mitigate infection-related immune responses.Furthermore, the above findings focus on addressing the problem of AMR in Post-Pandemic, which will for sure attract attention from both academic and industry research.

Evaluation of anti-vibriocidal, antioxidant properties and cytotoxicity of bio fabricated/green synthesized silver nanoparticles using Euphorbia hitra L. leaf extract

The increasing focus on combating antimicrobial resistance (AMR) in aquaculture sector is driving innovations and better improvements to save billions of dollars globally. Two gram- negative bacteria which cause vibriosis, Vibrio parahaemolytics and Vibrio harveyi, are now resistant to multiple antibiotics. Green technology has evolved to produce novel antimicrobials with reduced potential for AMR and sustainable synthesis. The present study utilized a one-pot biofabrication method to synthesize silver nanoparticles (AgNPs) using Euphorbia hitra leaf aqueous extract (EHLAE) through a bottom-up approach. The qualitative phytochemical examination of EHLAE confirmed the existence of diverse components including steroids, carbohydrates, alkaloids, flavonoids, tannins, terpenoids, saponins, glycosides, and phenols. These compounds have crucial role as reducing and capping AgNPs. The obtained gAgNPs were subjected to evaluate the physico-chemical properties such as Surface Plasmon Resonance (SPR), functional groups, and crystalline structure, were verified by UV-Vis spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), and X-ray diffraction (XRD). The morphology, elemental composition, and size distribution of the AgNPs synthesized using a green method were confirmed using advanced techniques including Field Emission Scanning Electron Microscope (FESEM) with Energy Dispersive X-ray spectroscopy (EDX), High-Resolution Transmission Electron Microscope (HRTEM), and Dynamic Light Scattering (DLS). The silver nanoparticles (AgNPs) shown potent anti-vibriocidal activity against both Vibrio parahaemolyticus and Vibrio harveyi and the Minimum Inhibitory Concentration (MIC) for both bacteria were consistently 31.25 µg mL−1. The in vitro antioxidant tests showed effective results and the found IC50 values are 306 µg mL−1 for DPPH and 6.46 µg mL−1 for FRAP assays. Furthermore, the assessment of in vitro cytotoxicity on Vero cell lines revealed minimal toxicity, as evidenced by an IC50 value of 191.51 µg mL−1. The results reveals that the green synthesized AgNPs using Euphorbia hitra leaf have the potential to be used as effective alternatives for therapeutic purposes in combating the increasing problem of antimicrobial resistance in the aquaculture industry.

The Role of Molecular Dynamics Simulations in Elucidating Interactions between Antimicrobial Peptides and Model Biological Membranes

In addressing the global problem of antimicrobial resistance, an emerging class of molecules called antimicrobial peptides (AMPs) are being widely studied. Their interactions with cell membranes are instrumental in their killing action, usually by forming pores or translocating to act on an internal target. Molecular dynamics (MD) simulations have played an essential role in understanding the atomistic mechanisms of such interactions. This review will highlight key findings from various MD studies, such as the formation of nanoaggregates and different types of pores. We will also discuss the role of selecting the membrane model composition, the level of detail in the simulation, and the choice of force field. It is evident in this review that our understanding of the interactions of AMPs and membranes has grown over the recent years through the help of MD simulations. Still, remaining concerns in MD studies of such systems must be addressed to gain more information.

The longitudinal trend and influential factors exploring of global antimicrobial resistance in Klebsiella pneumoniae

Klebsiella pneumoniae (Kp) is a human symbiotic opportunistic pathogen capable of causing severe hospital-based infections and community-acquired infections. The problem of antimicrobial resistance (AMR) has become increasing serious over time, posing a major threat to socio-economic and human development. In this study, we explored the global trend of AMR in 1786 strains of Kp isolated between 1982 and 2023. The number of antibiotic resistance genes (ARGs) in Kp increased significantly from 24.29 ± 5.44 to 32.42 ± 8.52 over time. Mobile genetic elements (MGEs) were responsible for the ARGs horizontal transfer of Kp strains. The results of structural equation modeling (SEM) indicated a strong association between the human development index and the increase of antibiotic consumption, which indirectly affected the occurrence and development of antibiotic resistance in Kp. The results of Generalized Linear Models (GLM) indicated that the influence of environmental factors such as temperature on the development of Kp resistance could not be ignored. Overall, this study monitored the longitudinal trend of antimicrobial resistance in Kp, explored the factors influencing antibiotic resistance, and provided insights for mitigating the threat of antimicrobial resistance.

Microbiological and Molecular Investigation of Antimicrobial Resistance in Staphylococcus aureus Isolates from Western Romanian Dairy Farms: An Epidemiological Approach.

Antimicrobial therapy is the most frequently used medical intervention for bovine mastitis in the dairy industry. This study aims to monitor the extent of the antimicrobial resistance (AMR) problem in Staphylococcus aureus in the dairy industry in Western Romania. Twenty farms were selected by random sampling in a transverse epidemiological study conducted across four counties in Western Romania and divided into livestock units. This study assessed the association between the resistance genes to phenotypic expression of resistance and susceptibility. Isolates of S. aureus were identified and q-PCR reactions were used to detect antibiotic resistance genes. One hundred and fifty bovine and 20 human samples were positive for S. aureus. Twenty five percent of bovine isolates (30/120) and none(0/30) of the human isolates were methicillin-resistant S. aureus (MRSA). All isolates were susceptible to fosfomycin, ciprofloxacin, netilmicin, and resistant to ampicillin and penicillin. S. aureus isolates regarded as phenotypically resistant (R) were influenced by the origin of the samples (human versus bovine, χ2 = 36.510, p = 0.013), whether they were methicillin-resistant S. aureus (χ2 = 108.891, p < 0.000), the county (χ2 = 103.282, p < 0.000) and farm of isolation (χ2 = 740.841, p < 0.000), but not by the size of the farm (χ2 = 65.036, p = 0.306). The multiple antibiotic resistance index was calculated for each sample as the number regarded as phenotypically resistant (R)/total antibiotics tested (MARI = 0.590 ± 0.023) was significantly higher (p < 0.000) inmethicillin-resistant S. aureus (0.898 ± 0.019) than non-methicillin-resistant S. aureus (0.524 ± 0.024) isolates. For the antibiotics tested, the total penetrance (P%) of the resistance genes was 59%, 83% for blaZ, 56% for cfr, 50% for erm(B), 53% for erm(C), 57% for mecA and 32% for tet(K). Penetrance can be used as a parameter for guidance towards a more accurate targeting of chemotherapy. P% in S. aureus was strongly positively correlated with the multiple antibiotic resistance index (r = +0.878, p < 0.000) with the potential to use the same limit value as an antibiotic management decision criterion. Considering cow mastitis, the penetrance value combined with the multiple antibiotic resistance index suggests that penetrance could serve as a useful parameter for more precise targeting of chemotherapy for S. aureus.

Bacteriophage therapy in the management of diabetic foot ulcer infections

AbstractThe global morbidity, mortality and health economic effects of treating patients with diabetic foot ulcer infections are rapidly growing and have been exacerbated by the problem of antimicrobial resistance. With the world on the cusp of entering the postantibiotic era, alternative antimicrobial strategies are urgently needed. Bacteriophage therapy has demonstrated safety, efficacy and cost‐effectiveness in treating patients with diabetic foot ulcer infections. This review seriously considers the use of bacteriophage therapy in the care of patients with diabetic foot ulcer infections.

On-Site Inactivation for Disinfection of Antibiotic-Resistant Bacteria in Hospital Effluent by UV and UV-LED.

The problem of antimicrobial resistance (AMR) is not limited to the medical field but is also becoming prevalent on a global scale in the environmental field. Environmental water pollution caused by the discharge of wastewater into aquatic environments has caused concern in the context of the sustainable development of modern society. However, there have been few studies focused on the treatment of hospital wastewater, and the potential consequences of this remain unknown. This study evaluated the efficacy of the inactivation of antimicrobial-resistant bacteria (AMRB) and antimicrobial resistance genes (AMRGs) in model wastewater treatment plant (WWTP) wastewater and hospital effluent based on direct ultraviolet (UV) light irradiation provided by a conventional mercury lamp with a peak wavelength of 254 nm and an ultraviolet light-emitting diode (UV-LED) with a peak emission of 280 nm under test conditions in which the irradiance of both was adjusted to the same intensity. The overall results indicated that both UV- and UV-LED-mediated disinfection effectively inactivated the AMRB in both wastewater types (>99.9% after 1-3 min of UV and 3 min of UV-LED treatment). Additionally, AMRGs were also removed (0.2-1.4 log10 for UV 254 nm and 0.1-1.3 log10 for UV 280 nm), and notably, there was no statistically significant decrease (p < 0.05) in the AMRGs between the UV and UV-LED treatments. The results of this study highlight the importance of utilizing a local inactivation treatment directly for wastewater generated by a hospital prior to its flow into a WWTP as sewage. Although additional disinfection treatment at the WWTP is likely necessary to remove the entire quantity of AMRB and AMRGs, the present study contributes to a significant reduction in the loads of WWTP and urgent prevention of the spread of infectious diseases, thus alleviating the potential threat to the environment and human health risks associated with AMR problems.