Antibiotic resistant bacteria: A bibliometric review of literature

Distribution status and influencing factors of antibiotic resistance genes in the Chaohu Lake, China

Background

Chaohu Lake (CL) is one of the most polluted areas in China due to its high content of antibiotics. However, the distribution and influencing factors of antibiotic resistance genes (ARGs) in this lake are still controversial.

Methods

To solve this problem, we used metagenomic sequencing to investigate the distribution and in-fluencing factors of ARGs in CL.

Results

Our findings revealed the existence of nine kinds of ARGs, including 45 specific genes. The most abundant types were multidrug, bacitracin, polymyxin, macrolide lincosamide streptogramin, and aminoglycoside. Multiple microorganisms were undeniable ARG reservoirs, although they were not dominant species in the microbiota. Our results also showed that both the microbiota and physiochemical factors played important roles in shaping the distributions of ARGs in CL. Specifically, the levels of PO4-P (0.5927) and total phosphorus (0.4971) had a greater impact than total nitrogen (0.0515), NO3-N (0.0352), NO2-N (-0.1975), and NH3-N (-0.0952).

Conclusions

These findings provide valuable insights into the distribution and influencing factors of ARGs in lakes.

The Current Status, Hotspots, and Development Trends of Nanoemulsions: A Comprehensive Bibliometric Review

Nanoemulsions, which are characterized by their nanometer-scale droplets, have gained significant attention in different fields, such as medicine, food, cosmetics, and agriculture, because of their unique properties. With an increasing number of countries engaging in research on nanoemulsions, interest in their properties, preparation methods, and applications has increased. Hence, tracing the relevant research on nanoemulsions published in the past ten years on a global scale, by conducting data mining and visualization analysis on a sufficiently large text dataset through bibliometrics, sorting out and summarizing certain indicators, the development history, research status and research hotspots in the field of nanoemulsions can be clearly revealed, providing reference value and significance for subsequent research. This bibliometric review examines the research landscape of nanoemulsions from 2013-2023 via the SCI-E and SSCI databases, providing insights into the current status, hotspots, and future trends of this field. To offer a comprehensive overview, this analysis includes publication counts, author keywords, institutional contributions, research areas, prolific authors, highly cited papers and hot research papers. The findings reveal that China led in nanoemulsions research, followed by USA, India, and Brazil, with the University of Massachusetts emerging as a key player with the highest average number of citations per article (ACPP) and h-index. Food Chemistry, Pharmaceutics, and the Journal of Drug Delivery Science and Technology are among the top journals publishing in this area. Chemistry, pharmacology, and pharmacy emerged as the primary research domains, with McClements DJ as the most prolific and influential author. In keyword analysis, essential oil nanoemulsions are currently the main preparation direction, and various characteristics of nanoemulsions, such as their bioavailability, stability, biocompatibility, and antioxidant and antibacterial properties, have also been studied extensively. Research hotspots are focused mostly on the development of new applications and technologies for nanoemulsions.

Genome-Guided Identification and Characterisation of Broad-Spectrum Antimicrobial Compounds of Bacillus velezensis Strain PD9 Isolated from Stingless Bee Propolis

The emergence of multidrug-resistant pathogens presents a significant global health challenge, which is primarily fuelled by overuse and misuse of antibiotics. Bacteria-derived antimicrobial metabolites offer a promising alternative strategy for combating antimicrobial resistance issues. Bacillus velezensis PD9 (BvPD9), isolated from stingless bee propolis, has been reported to have antibacterial activities against methicillin-resistant Staphylococcus aureus (MRSA). This study aimed to characterise and identify the antimicrobial compounds (AMCs) synthesised by BvPD9 through integration of genome mining and liquid chromatography-mass spectrometry (LC-MS) analysis. The whole-genome sequence of BvPD9 contained 4,263,351 base pairs and 4101 protein-coding sequences, with 12 potential AMC biosynthetic gene clusters. Comparative genomic analysis highlighted the unique profile of BvPD9 that possesses the largest number of unknown proteins, indicating significant potential for further exploration. The combined genomics-metabolic profiling uncovered five AMCs in BvPD9 extract, including bacillibactin, bacilysin, surfactin A, fengycin A, and bacillomycin D. The extract exhibited a broad antibacterial spectrum against 25 pathogenic bacteria, including both Gram-positive and Gram-negative bacteria, with the lowest minimum inhibitory concentration (MIC, 0.032 mg/ml) against S. epidermidis ATCC 12228, and the lowest minimum bactericidal concentration (MBC; 0.128 mg/ml) against MRSA ATCC 700699 and Aeromonas hydrophilia. The robust stability of BvPD9 extract was demonstrated at high temperatures, over a wide range of pH conditions (6 to 12) and in the presence of various hydrolytic enzymes. Additionally, the extract showed 50% haemolytic and cytotoxicity activity at 0.158 and 0.250 mg/ml, respectively. These characteristics suggest potential applications of BvPD9 metabolites for tackling antimicrobial resistance and its applicability across diverse industries.

Prevalence of antibiotic-resistant enterobacteriaceae in domestic wastewater and associated health risks in reuse practices

The use of wastewater for non-potable purposes is an important alternative for addressing water scarcity, especially in developing regions. However, minimizing the risks, particularly those associated with emerging contaminants that may induce resistance among pathogens in wastewater, is crucial. This study assessed the occurrence of antibiotic-resistant bacteria in untreated wastewater used for agricultural purposes and evaluated the quantifiable health risks associated with this practice in Tamale, Ghana. The resistance of some Enterobacteriaceae, such as E. coli, Klebsiella, and Salmonella-Shigella, to four commonly used antibiotics in Ghana was assessed using a conventional microbiological culture approach and the Kirby Bauer disk diffusion method. A Quantitative Microbial Risk Assessment (QMRA) was performed to estimate the health risks associated with two distinct scenarios of wastewater reuse: (1) accidental ingestion of contaminated wastewater and soil, and (2) consumption of vegetables irrigated with wastewater. This approach applied a Monte Carlo simulation based on 10,000 interactions and identified E. coli O157:H7 as the reference pathogen. Among Enterobacteriaceae, Klebsiella pneumoniae, Salmonella-Shigella and E. coli were isolated, in concentrations exceeding the limit recommended by the World Health Organization (103 CFU/100 ml). All the isolated bacteria were resistant to metronidazole (5 μg). Thirty-three per cent of Klebsiella pneumoniae isolates were intermediate/moderately susceptible, and all other bacteria were resistant to amoxicillin (30 μg). All Klebsiella pneumoniae and the majority of Salmonella-Shigella (69.8 %) isolates were resistant to trimethoprim-sulfamethoxazole (25 μg) and tetracycline (30 μg). When assessing health risks, the mean annual probability of infection associated with consuming vegetables irrigated with wastewater varied between 5.14 × 10-2 and 9.79 × 10-1 per person per year. Conversely, for the accidental ingestion scenario, the probability was 1.00 per person per year. In these scenarios, the probability of illness ranged from 1.29 × 10-2 to 2.4 × 10-1 and 2.5 × 10-1 per person per year. The health risks posed by these findings surpass the maximum threshold prescribed by the World Health Organization, thereby emphasizing the need for prompt mitigation strategies.

In vitro and in silico insights into antimicrobial and anticancer activities of novel imidazo[2,1-b][1,3,4]thiadiazoles

This study explores the design, synthesis, and evaluation of a novel series of isobenzofuran-based imidazo[2,1-b][1,3,4]thiadiazole derivatives, targeting their antimicrobial and anticancer properties. These compounds integrate the pharmacologically significant 1,3,4-thiadiazole and imidazole moieties, which are known for their potential in drug development, although imidazo[2,1-b][1,3,4]thiadiazole-based drugs are not yet available on the market. Therefore, the aim of this study is to develop novel derivatives that could serve as promising candidates for future therapeutic applications. The derivatives were synthesized in two steps and thoroughly characterized using IR, 1H NMR, 13C NMR, and mass spectrometry. All the derivatives had shown fairly good antimicrobial activity against four microorganisms (Escherichia coli, Staphylococcus aureus, Mycobacterium smegmatis and Candida albicans) with minimum inhibition concentration's ranging from 0.14 to 0.59 mM. The anticancer activity of the compounds against MCF-7 cell lines showed promising activity, where three derivatives, 3a, 3c and 3d exhibited better inhibition than the standard, cisplatin. The highest anticancer activity was shown by the derivative 3c with an IC50 value of 35.81 μM. Molecular docking was studied to determine the docking poses and binding interaction of the derivatives with the protein bearing PDB: 5BNS and 3ZNR; ADME properties of the derivatives are also inferred which gives insights into the bioavailability. The molecular dynamics simulation of the derivative 3c with HDAC7 protien (PDB: 3ZNR) was evalauted to determine the stability of the interaction between the protein and the ligand.

Global trends and future directions on carbapenem-resistant Enterobacteriaceae (CRE) research: A comprehensive bibliometric analysis (2020-2024)

The increasing prevalence of carbapenem-resistant Enterobacteriaceae (CRE) poses a significant threat to public health. CRE, particularly Klebsiella pneumoniae, is associated with high morbidity and mortality owing to limited treatment options. This study identifies current research trends, major topics, and future directions in the scientific field of CRE. We systematically retrieved publications from the Web of Science database starting from 2020 to January 07, 2024. Using bibliometric tools such as VOSviewer, CiteSpace, and InCites, we analyzed publication counts, citation analysis, co-authorship, keyword co-occurrence, and thematic development to map the landscape and collaborative networks in the field. The search included keywords such as "carbapenem-resistant Enterobacteriaceae," "carbapenemase-producing Enterobacteriaceae," "carbapenemase-producing Klebsiella pneumoniae," and "Klebsiella pneumoniae carbapenemase." We reviewed 1946 articles. The largest contributors to the field were China, the United States, and Italy. This study highlights the significant increase in CRE-related publications, particularly in the context of hospital-acquired infections, antimicrobial resistance mechanisms, and novel therapeutic approaches. Keyword trend analysis revealed epidemiology, molecular biology, infection control, and public health implications, signaling a shift towards the broader impact of CRE in healthcare settings. This bibliometric analysis maps the current research landscape and identifies key areas for further research. Continued progress is essential to develop strategies to combat antimicrobial resistance and to improve patient outcomes.

Emerging trends and hotspots in intestinal microbiota research in sepsis: bibliometric analysis

Background

The association between the gut microbiota and sepsis has garnered attention in the field of intestinal research in sepsis. This study utilizes bibliometric methods to visualize and analyze the literature on gut microbiota research in sepsis from 2011 to 2024, providing a scientific foundation for research directions and key issues in this domain.

Methods

Original articles and reviews of gut microbiota research in sepsis, which published in English between 2011 and 2024, were obtained from the Web of Science Core Collection on June 21, 2024. Python, VOSviewer, and CiteSpace software were used for the visual analysis of the retrieved data.

Results

A total of 1,031 articles were analyzed, originating from 72 countries or regions, 1,614 research institutions, and 6,541 authors. The articles were published in 434 different journals, covering 89 different research fields. The number of publications and citations in this research area showed a significant growth trend from 2011 to 2024, with China, the United States, and the United Kingdom being the main research forces. Asada Leelahavanichkul from Thailand was identified as the most prolific author, making him the most authoritative expert in this field. "Nutrients" had the highest number of publications, while "Frontiers in Cellular and Infection Microbiology," "Frontiers in Immunology" and "the International Journal of Molecular Sciences" have shown increasing attention to this field in the past 2 years. Author keywords appearing more than 100 times included "gut microbiota (GM)," "sepsis" and "microbiota." Finally, this study identified "lipopolysaccharides (LPS)," "short-chain fatty acids (SCFAs)," "probiotics," "fecal microbiota transplantation (FMT)" and "gut-liver axis" as the research hotspots and potential frontier directions in this field.

Conclusion

This bibliometric study summarizes current important perspectives and offers comprehensive guidance between sepsis and intestinal microbiota, which may help researchers choose the most appropriate research directions.

Natural Antimicrobial Agents from Algae: Current Advances and Future Directions

Infectious diseases have significantly shaped human history, leading to significant advancements in medical science. The discovery and development of antibiotics represented a critical breakthrough, but the rise of antibiotic-resistant pathogens now presents a serious global health threat. Due to the limitations of current synthetic antimicrobials, such as toxicity and environmental concerns, it is essential to explore alternative solutions. Algae, particularly microalgae and cyanobacteria, have emerged as promising sources of bioactive antimicrobial compounds. This review provides a comprehensive analysis of the antimicrobial properties of algal-derived compounds, including polysaccharides, fatty acids, and phenols, which have shown effectiveness against multi-drug-resistant bacteria. A co-occurrence bibliometric analysis using VOSviewer highlighted five key research clusters: antibiotic resistance, algal extracts, biosynthesis, water treatment, and novel pharmacological compounds. Furthermore, the primary mechanisms of action of these bioactive compounds, such as the inhibition of protein synthesis and cell membrane disruption, were identified, demonstrating their potential against both common and multi-resistant pathogens. Future research should prioritize optimizing algal biomass production, utilizing genetic and metabolic engineering, and creating innovative delivery systems to enhance the efficient production of bioactive compounds.

Review of Antimicrobial Properties of Titanium Dioxide Nanoparticles

There is a growing interest in the utilization of metal oxide nanoparticles as antimicrobial agents. This review will focus on titanium dioxide nanoparticles (TiO2 NPs), which have been demonstrated to exhibit high antimicrobial activity against bacteria and fungi, chemical stability, low toxicity to eukaryotic cells, and therefore high biocompatibility. Despite the extensive research conducted in this field, there is currently no consensus on how to enhance the antimicrobial efficacy of TiO2 NPs. The aim of this review is to evaluate the influence of various factors, including particle size, shape, composition, and synthesis parameters, as well as microbial type, on the antibacterial activity of TiO2 NPs against bacteria and fungi. Furthermore, the review offers a comprehensive overview of the methodologies employed in the synthesis and characterization of TiO2 NPs. The antimicrobial activity of TiO2 exhibits a weak dependence on the microorganism species. A tendency towards increased antibacterial activity is observed with decreasing TiO2 NP size. The dependence on the shape and composition is more pronounced. The most pronounced antimicrobial potential is exhibited by amorphous NPs and NPs doped with inorganic compounds. This review may be of interest to specialists in biology, medicine, chemistry, and other related fields.

Larimichthys crocea (large yellow croaker): A bibliometric study

Larimichthys crocea is an important economic fish of East Asia, and numerous studies have been conducted on its breeding, aquaculture, preservation and processing; however, there is no systematic review of the literature on the research of Larimichthys crocea. Derwent Data Analyzer (DDA) was used to analyze 1192 Larimichthys crocea research papers indexed by SCI-E, CSCD and KCI from 2001 to 2023. The number of research publications on Larimichthys crocea has rapidly increased, and institutions and scholars from China, the United States, South Korea, Japan, and Norway have conducted the majority of Larimichthys crocea research. The immune response, Pseudomonas plecoglossicida, gene expression, lipid immune response, transcriptomics and other areas have attracted the most attention. To increase the immunity and disease resistance of Larimichthys crocea and improve its survival, growth, storage and transport, researchers have carried out a large amount of research, which has promoted not only the culture of Larimichthys crocea but also the restoration of wild Larimichthys crocea and the rehabilitation of the ecological environment.

Trends in horizontal gene transfer research in Salmonella antimicrobial resistance: a bibliometric analysis

Horizontal gene transfer (HGT) favors the acquisition and spread of antimicrobial resistance (AMR) genes in Salmonella, making it a major public health concern. We performed a bibliometric analysis to provide the current landscape of HGT in research on Salmonella AMR and identify emerging trends and potential research directions for the future. Data were collected from the Web of Science Core Collection and limited to articles and reviews published between 1999 and 2024 in English. VOSviewer 1.6.19 and CiteSpace 6.2.R1 software were used to conduct bibliometric analysis and visualize co-occurring keywords. A total of 1,467 publications were retrieved for analysis. American researchers contributed the most articles (n = 310). In the meantime, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement have the highest citation/publication rate of 85.6. Recent studies have focused on the application of whole genome sequencing (WGS), Salmonella quinolone and colistin resistance, and the biocontrol of Salmonella AMR. These findings provide new insights into the role of HGT and help identify new targets for controlling the spread of AMR in Salmonella populations.

Antimicrobial photodynamic therapy against Escherichia coli by exploiting endogenously produced Protoporphyrin IX- In vitro study

Due to antimicrobial drug resistance, there is a growing interest in the development of light based alternative antibacterial therapies. This research work is focused on the inactivation of Escherichia coli (E. coli) by exploiting the absorption bands 405, 505, 542, 580 and 631 nm of its indigenously produced Protoporphyrin IX (PpIX) excited by three LEDs with broad emission bands at 418, 522 and 630 nm and two laser diodes with narrow emission bands at 405 and 635 nm. Fluorescence spectroscopy and plate count method have been employed for studying the inactivation rate of E. coli strain in autoclaved water suspension. It has been found that LEDs at 418, 522 and 630 nm produced pronounced antimicrobial photodynamic effect on E. coli strain comparing laser diodes at 405 and 635 nm, which might be attributed to the overlapping of broad emission bands of LEDs with the absorption bands of PpIX than narrow emission bands of laser diodes. Particular effect of LED at 522 nm has been noticed because its broad emission band overlaps three absorption bands 505, 542 and 580 nm of PpIX. The gold standard plate count method strongly correlates with Fluorescence spectroscopy, making it an innovative tool to administer bacterial inactivation. The experimental results suggested the development of a light source that entirely overlap absorption bands of PpIx to produce a pronounced antimicrobial photodynamic effect, which might become an effective modality for in vivo disinfection of antibiotic resistant microbes in wounds and lesions.

Impact of Introducing a Multiplex Polymerase Chain Reaction Blood Culture Panel on Anti-Methicillin-Resistant Staphylococcus aureus (MRSA) and Carbapenem Antimicrobial Agents in a Children's Hospital

BACKGROUND

With the advent of multiplex polymerase chain reaction (PCR) using samples from a positive blood culture, the time required to identify a pathogen has significantly shortened to a few hours. It can help us select appropriate antimicrobial agents more quickly. The present study aimed to assess the impact of using a multiplex PCR blood culture panel on the appropriate administration of antimicrobial agents.

METHODS

Patients aged <16 years with culture-confirmed bacteremia at Tokyo Metropolitan Children's Medical Center were enrolled. A pre-intervention period (period I: December 2016 to December 2018) and a post-intervention period with multiplex PCR use for the confirmation of positive blood cultures (period II: December 2019 to December 2021) were compared for their effect on the use of antimicrobial agents for gram-positive cocci (GPC) and gram-negative rod (GNR) bacteremia. Data on patient background, blood culture results, and antimicrobial use were retrospectively collected from electronic medical records.

RESULTS

Periods I and II had 174 and 154 patients, respectively. The median age at periods I and II was 14 (IQR 2-82) months and 12 (IQR 1-78) months, respectively. GPC bacteremia during periods I and II occurred in 140 and 115 patients, respectively. GNR during periods I and II occurred in 34 and 39 patients, respectively. Neither the vancomycin-resistance genes A/B nor the carbapenem-resistance gene were detected. The use of antimicrobial agents against anti-methicillin-resistant Staphylococcus aureus (MRSA) for GPC bacteremia decreased from 103/140 cases (73%) in period I to 56/115 cases (49%) in period II (p=0.047). The use of carbapenems for GNR bacteremia did not change significantly, at 23/34 (68%) in period I and 34/39 (87%) in period II (p=0.47).

CONCLUSION

Introducing multiplex PCR for pediatric bacteremia decreased the use of anti-MRSA antimicrobial agents but not of carbapenems.

Antibiotic-Resistant Bacteria Isolated from Street Foods: A Systematic Review

Street food may be a vehicle of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) to humans. Foods contaminated with ARB entail serious problems or challenges in the fields of medical care, animal husbandry, food industry, and public health worldwide. The objectives of this systematic review were to identify and evaluate scientific reports associated with ARB isolated from various street foods. "Preferred reporting items for systematic reviews and meta-analysis" (PRISMA) guidelines were followed. The bibliographic material covers a period from January 2015 to April 2024. Six electronic scientific databases were searched individually for full-text articles; only those papers that met the inclusion and exclusion criteria were selected. Seventeen papers were included in this systematic review. This study highlighted the wide distribution of ARB resistant to β-lactams and other antibiotics, posing significant health risks to consumers. High resistance levels were observed for antibiotics such as ampicillin, ceftriaxone, and tetracycline, while some antibiotics, such as ceftazidime, clavulanic acid, cefoperazone, cotrimoxazole, doxycycline, doripenem, fosfomycin, vancomycin, and piperacillin-tazobactam, demonstrated 100% susceptibility. The prevalence of ARB in street foods varied between 5.2% and 70.8% among different countries. The multiple resistance of various bacteria, including Escherichia coli, Staphylococcus, Salmonella, and Klebsiella, to multiple classes of antibiotics, as well as environmental factors contributing to the spread of antibiotic resistance (AR), emphasize the urgent need for comprehensive approaches and coordinated efforts to confront antimicrobial resistance (AMR) under the "One Health" paradigm.

Global research progress of endothelial cells and ALI/ARDS: a bibliometric analysis

Background

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are severe respiratory conditions with complex pathogenesis, in which endothelial cells (ECs) play a key role. Despite numerous studies on ALI/ARDS and ECs, a bibliometric analysis focusing on the field is lacking. This study aims to fill this gap by employing bibliometric techniques, offering an overarching perspective on the current research landscape, major contributors, and emerging trends within the field of ALI/ARDS and ECs.

Methods

Leveraging the Web of Science Core Collection (WoSCC) database, we conducted a comprehensive search for literature relevant to ALI/ARDS and ECs. Utilizing Python, VOSviewer, and CiteSpace, we performed a bibliometric analysis on the corpus of publications within this field.

Results

This study analyzed 972 articles from 978 research institutions across 40 countries or regions, with a total of 5,277 authors contributing. These papers have been published in 323 different journals, spanning 62 distinct research areas. The first articles in this field were published in 2011, and there has been a general upward trend in annual publications since. The United States, Germany, and China are the principal contributors, with Joe G. N. Garcia from the University of Arizona identified as the leading authority in this field. American Journal of Physiology-Lung Cellular and Molecular Physiology has the highest publication count, while Frontiers in Immunology has been increasingly focusing on this field in recent years. "Cell Biology" stands as the most prolific research area within the field. Finally, this study identifies endothelial glycocalyx, oxidative stress, pyroptosis, TLRs, NF-κB, and NLRP3 as key terms representing research hotspots and emerging frontiers in this field.

Conclusion

This bibliometric analysis provides a comprehensive overview of the research landscape surrounding ALI/ARDS and ECs. It reveals an increasing academic focus on ALI/ARDS and ECs, particularly in the United States, Germany, and China. Our analysis also identifies several emerging trends and research hotspots, such as endothelial glycocalyx, oxidative stress, and pyroptosis, indicating directions for future research. The findings can guide scholars, clinicians, and policymakers in targeting research gaps and setting priorities to advance the field.

Potent Inhibition of E. coli DXP Synthase by a gem-Diaryl Bisubstrate Analog

New antimicrobial strategies are needed to address pathogen resistance to currently used antibiotics. Bacterial central metabolism is a promising target space for the development of agents that selectively target bacterial pathogens. 1-Deoxy-d-xylulose 5-phosphate synthase (DXPS) converts pyruvate and d-glyceraldehyde 3-phosphate (d-GAP) to DXP, which is required for synthesis of essential vitamins and isoprenoids in bacterial pathogens. Thus, DXPS is a promising antimicrobial target. Toward this goal, our lab has demonstrated selective inhibition of Escherichia coli DXPS by alkyl acetylphosphonate (alkylAP)-based bisubstrate analogs that exploit the requirement for ternary complex formation in the DXPS mechanism. Here, we present the first DXPS structure with a bisubstrate analog bound in the active site. Insights gained from this cocrystal structure guided structure-activity relationship studies of the bisubstrate scaffold. A low nanomolar inhibitor (compound 8) bearing a gem-dibenzyl glycine moiety conjugated to the acetylphosphonate pyruvate mimic via a triazole-based linker emerged from this study. Compound 8 was found to exhibit slow, tight-binding inhibition, with contacts to E. coli DXPS residues R99 and R478 demonstrated to be important for this behavior. This work has discovered the most potent DXPS inhibitor to date and highlights a new role of R99 that can be exploited in future inhibitor designs toward the development of a novel class of antimicrobial agents.

Bibliometric Insights Into the Evolving Landscape of Antibiotic Resistance Research: Trends, Collaborations, and Key Foci (1965-2023)

Conducted on randomized clinical trials (RCTs) addressing antibiotic resistance in the PubMed database, this bibliometric analysis explores relevant sources, keyword co-occurrence, institutional co-authorship, global collaboration patterns, and evolving research trends. Utilizing an electronic search on January 13, 2024, employing the term "antibiotic resistance," 252,657 results were retrieved, of which 2,962 RCTs were analyzed. The dissemination of RCTs exhibited a variable distribution from 1965 to 2023, with a peak in 2014, noteworthy peaks in 1993-1994 and 2002-2003, contrasting declines in 1990-1991 and 2007-2008, and a consistent decrease post 2018. The University of California emerged as a predominant institution, and the journal "Antimicrobial Agents and Chemotherapy" substantially contributed. The annual growth rate stood at 1.2%, with 97 single-authored documents, an average of 8.76 co-authors per document, and 8.89% international co-authorships. Co-occurrence analysis highlighted prevalent themes, including double-blind clinical trials and significant keywords like human immunodeficiency virus (HIV) infections, Helicobacter infections, metronidazole, and amoxicillin. Trend analysis revealed a chronological shift from penicillin to HIV and Helicobacter drug therapies, culminating in combination antibacterial therapy for multiple bacterial strains. The prevailing trend in antibiotic resistance publications involved single-country endeavors, with the United States leading in collaboration frequency. The findings indicate a need to foster international collaboration, promote interdisciplinary research, support emerging trends, encourage open-access publication, and address declines in research activity, particularly RCTs.

Ring-opening metathesis polymerization of N-methylpyridinium-fused norbornenes to access antibacterial main-chain cationic polymers

Cationic polymers have been identified as a promising type of antibacterial molecules, whose bioactivity can be tuned through structural modulation. Recent studies suggest that the placement of the cationic groups close to the core of the polymeric architecture rather than on appended side chains might improve both their bioactivity and selectivity for bacterial cells over mammalian cells. However, antibacterial main-chain cationic polymers are typically synthesized via polycondensations, which do not afford precise and uniform molecular design. Therefore, accessing main-chain cationic polymers with high degrees of molecular tunability hinges upon the development of controlled polymerizations tolerating cationic motifs (or cation progenitors) near the propagating species. Herein, we report the synthesis and ring-opening metathesis polymerization (ROMP) of N-methylpyridinium-fused norbornene monomers. The identification of reaction conditions leading to a well-controlled ROMP enabled structural diversification of the main-chain cationic polymers and a study of their bioactivity. This family of polyelectrolytes was found to be active against both Gram-negative (Escherichia coli) and Gram-positive (Methicillin-resistant Staphylococcus aureus) bacteria with minimal inhibitory concentrations as low as 25 µg/mL. Additionally, the molar mass of the polymers was found to impact their hemolytic activity with cationic polymers of smaller degrees of polymerization showing increased selectivity for bacteria over human red blood cells.

Enhancing the Antimicrobial Properties of Peptides through Cell-Penetrating Peptide Conjugation: A Comprehensive Assessment

Combining antimicrobial peptides (AMPs) with cell-penetrating peptides (CPPs) has shown promise in boosting antimicrobial potency, especially against Gram-negative bacteria. We examined the CPP-AMP interaction with distinct bacterial types based on cell wall differences. Our investigation focused on AMPs incorporating penetratin CPP and dihybrid peptides containing both cell-penetrating TAT protein fragments from the human immunodeficiency virus and Antennapedia peptide (Antp). Assessment of the peptides TAT-AMP, AMP-Antp, and TAT-AMP-Antp revealed their potential against Gram-positive strains (Staphylococcus aureus, Methicillin-resistant Staphylococcus aureus (MRSA), and Bacillus cereus). Peptides TAT-AMP and AMP-Antp using an amyloidogenic AMP from S1 ribosomal protein Thermus thermophilus, at concentrations ranging from 3 to 12 μM, exhibited enhanced antimicrobial activity against B. cereus. TAT-AMP and TAT-AMP-Antp, using an amyloidogenic AMP from the S1 ribosomal protein Pseudomonas aeruginosa, at a concentration of 12 µM, demonstrated potent antimicrobial activity against S. aureus and MRSA. Notably, the TAT-AMP, at a concentration of 12 µM, effectively inhibited Escherichia coli (E. coli) growth and displayed antimicrobial effects similar to gentamicin after 15 h of incubation. Peptide characteristics determined antimicrobial activity against diverse strains. The study highlights the intricate relationship between peptide properties and antimicrobial potential. Mechanisms of AMP action are closely tied to bacterial cell wall attributes. Peptides with the TAT fragment exhibited enhanced antimicrobial activity against S. aureus, MRSA, and P. aeruginosa. Peptides containing only the Antp fragment displayed lower activity. None of the investigated peptides demonstrated cytotoxic or cytostatic effects on either BT-474 cells or human skin fibroblasts. In conclusion, CPP-AMPs offer promise against various bacterial strains, offering insights for targeted antimicrobial development.

The Role of Five-Membered Heterocycles in the Molecular Structure of Antibacterial Drugs Used in Therapy

Five-membered heterocycles are essential structural components in various antibacterial drugs; the physicochemical properties of a five-membered heterocycle can play a crucial role in determining the biological activity of an antibacterial drug. These properties can affect the drug's activity spectrum, potency, and pharmacokinetic and toxicological properties. Using scientific databases, we identified and discussed the antibacterials used in therapy, containing five-membered heterocycles in their molecular structure. The identified five-membered heterocycles used in antibacterial design contain one to four heteroatoms (nitrogen, oxygen, and sulfur). Antibacterials containing five-membered heterocycles were discussed, highlighting the biological properties imprinted by the targeted heterocycle. In some antibacterials, heterocycles with five atoms are pharmacophores responsible for their specific antibacterial activity. As pharmacophores, these heterocycles help design new medicinal molecules, improving their potency and selectivity and comprehending the structure-activity relationship of antibiotics. Unfortunately, particular heterocycles can also affect the drug's potential toxicity. The review extensively presents the most successful five-atom heterocycles used to design antibacterial essential medicines. Understanding and optimizing the intrinsic characteristics of a five-membered heterocycle can help the development of antibacterial drugs with improved activity, pharmacokinetic profile, and safety.