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At least 19 recordsLinked to original sources

PubMed1979

Antimicrobial spectrum of triclosan, a broad-spectrum antimicrobial agent for topical application. II. Comparison with some other antimicrobial agents.

The antimicrobial activity of 5-chloro-2(2,4-dichlorophenoxy) phenol (triclosan, one of the active ingredients of Logamel, Ciba-Geigy) was compared in vitro with that of other antimicrobials exclusively or occasionally used as topical agents in dermatology: hexachlorophene, clioquinol, chlorquinaldol. gentamicin, neomycin, nystatin, econazole, clotrimazole and salicylic acid. Upon determination of the MICs for 53 strains of aerobic and anaerobic bacteria, yeasts and fungi, triclosan was found to display a high degree of activity against most of the test organisms and to have the broadest spectrum of chemotherapeutically significant antimicrobial activity of the substances tested.

Administration, Topical↗

PubMed2026

Evaluation of Oxford nanopore sequencing for antimicrobial resistance surveillance in Salmonella: comparison with phenotypic antimicrobial susceptibility in a large-scale study.

UNLABELLED: Salmonella is a major zoonotic foodborne pathogen, and antimicrobial resistance (AMR) in Salmonella presents a significant public health challenge. Compared with conventional antimicrobial susceptibility testing (AST), whole-genome sequencing (WGS) provides a more rapid and comprehensive approach to AMR characterization, thereby informing antimicrobial selection and supporting public health surveillance. In this study, Oxford Nanopore Technology (ONT)-based WGS was performed on 1,490 Salmonella isolates collected through nationwide surveillance in Taiwan in 2025. Genotypic resistance inferred from WGS data was compared with phenotypic AST results to assess the performance of ONT-WGS. Overall, WGS-inferred resistance showed high concordance with phenotypic resistance for most antimicrobials. However, major genotype-phenotype discordance was observed, attributed to four categories: (i) breakpoint-dependent classification, (ii) reduced or absent phenotypic expression of resistance genes, (iii) minimum inhibitory concentration (MIC) modulation by ramAp, and (iv) absence of known AMR determinants. Notable discrepancies included tigecycline resistance without known genetic determinants, nalidixic acid resistance linked to ramAp-mediated MIC elevation, and a high prevalence of colistin resistance (35.7%) in S. Enteritidis, with most resistant isolates lacking identifiable AMR determinants. Additionally, a significant proportion of ESBL- and AmpC-producing isolates were classified as susceptible or intermediate to cefotaxime and ceftazidime under CLSI criteria, highlighting the potential for misclassification and treatment failure. These findings demonstrate that ONT-WGS enables accurate and comprehensive AMR characterization by directly identifying resistance determinants and avoiding potential misclassification associated with breakpoint-based AST interpretations. When interpreted appropriately, WGS can support better antimicrobial selection and serve as a valuable alternative to conventional susceptibility testing. IMPORTANCE: Accurate prediction of antimicrobial resistance is essential for appropriate therapy and effective surveillance of Salmonella. However, discordance between genotype-based predictions and phenotypic antimicrobial susceptibility testing (AST) can complicate clinical interpretation. In this nationwide study of 1,490 Salmonella isolates, we show that Oxford Nanopore Technology-based whole-genome sequencing (ONT-WGS) provides rapid and comprehensive detection of antimicrobial resistance determinants with high concordance to phenotypic AST. We further identify four major mechanisms underlying genotype-phenotype discordance, including breakpoint-dependent classification, reduced or absent phenotypic expression of resistance genes, minimum inhibitory concentration (MIC) modulation by ramAp, and the absence of known AMR determinants. These findings demonstrate how WGS can complement conventional AST, improve interpretation of challenging susceptibility results, and strengthen genomic surveillance of emerging antimicrobial-resistant Salmonella.

Microbial Sensitivity Tests↗

PubMed1978

Hospital use of antimicrobial drugs. Survey at 19 hospitals and results of antimicrobial control program.

Costs and use of antimicrobial agents in 1976 at 19 hospitals were surveyed by review of pharmacy records. Total costs of antimicrobial drugs at individual hospitals ranged from $0.65 to $1.75 per patient day and accounted for 16% to 41% of total pharmacy drug costs. There was marked variation among hospitals in use of specific antimicrobial agents, especially cephalosporins and clindamycin. The cephalosporin and aminoglycoside antibiotics accounted for 66% of the total cost of antimicrobial agents. An 18-month antimicrobial drug control program at one hospital decreased antimicrobial drug costs by 31%. The major effect was in reducing cephalosporin use. The results of the control program document that a significant portion of hospital antimicrobial use is inappropriate and can be eliminated without apparent detriment to patient care.

Anti-Bacterial Agents↗

PubMed2025

Influence of antimicrobial consumption (AMC) on the detection of antimicrobial resistance genes (ARGs) in urban wastewater.

BACKGROUND: Antimicrobial resistance (AMR) is a global health threat, causing over 1.27 million deaths annually and linked to an additional 4.95 million. AMR transmission occurs beyond clinical settings, with wastewater serving as a sentinel of community-level spread. This study investigated how temporal changes in antimicrobial consumption (AMC) correlate with the prevalence of antimicrobial resistance genes (ARGs) in wastewater, using wastewater surveillance (WS) to monitor resistance trends in Quebec, Canada. METHODOLOGY: AMC data (January 2019-May 2023) were obtained from the Institut National de Santé Publique du Québec (INSPQ) under a license from IQVIA Solutions Canada Inc. Wastewater samples (September 2020-September 2022) were obtained from three WWTPs and screened for 11 ARGs, including blaTEM, blaSHV, blaCTX-M, blaNDM, blaOXA-1/30, qnrA, qnrB, mphE, and mefA. Analyses assessed temporal and spatial associations between AMC and ARGs. RESULTS: Total prescriptions declined from 537 to 392 per 1000 inhabitants between 2019 and 2020 (-27 %), likely due to the impact of the COVID-19 pandemic. This shift created a contrast that allowed us to better capture the signal of AMC through the noise in wastewater composition. β-lactams, macrolides, and fluoroquinolones were the most prescribed classes. ARGs were consistently detected in all 41 samples, with macrolide resistance genes being the most abundant. Strong correlations were observed between AMC and ARG prevalence in wastewater, particularly for β-lactams and fluoroquinolones (Spearman R = 0.80 and 0.81, p < 0.05). Spatial patterns showed uniform AMC but variable ARG levels. CONCLUSIONS: Our study highlights the correlation between AMC and ARG. WS shows promise for real-time AMR monitoring.

Wastewater↗

PubMed2026

National Antimicrobial Resistance Monitoring System: Three Decades of Advancing Public Health Through Integrated Surveillance of Antimicrobial Resistance.

Antimicrobial resistance (AMR) occurs when bacteria and other microorganisms adapt in ways that make medicines less effective, causing infections that are harder to treat and more likely to spread. According to the Centers for Disease Control and Prevention (CDC), AMR infections affect millions of Americans each year and contribute to thousands of deaths (CDC, 2019). After three decades of operation, the U.S. National Antimicrobial Resistance Monitoring System (NARMS) stands as a model of sustained, collaborative public health surveillance. What began in 1996 as an effort to track resistance in Salmonella and E. coli O157 has evolved into a One Health surveillance network monitoring AMR across the farm-to-fork continuum. Through a partnership among CDC, the Food and Drug Administration (FDA), the U.S. Department of Agriculture (USDA), state and local health departments, and universities, NARMS has become the backbone of foodborne AMR surveillance in the United States. The past decade has been particularly transformative. NARMS explored new sampling to include companion animals, minor livestock, aquaculture, surface water, and wildlife. Whole-genome sequencing (WGS) revolutionized the program's capabilities, enabling timely identification of emerging pathogens and revealing how resistance genes spread. Near real-time public dashboards make NARMS data accessible to researchers, clinicians, regulators, and policymakers. NARMS data shape decisions about new animal drug approvals, guide stewardship programs, and inform clinical treatment guidelines nationwide. As NARMS enters its fourth decade with a 2026-2030 strategic plan, the program will leverage artificial intelligence and metagenomics while expanding surveillance to fill remaining gaps ensuring this vital system continues to protect the food supply and both human and animal health from AMR.

Antimicrobial Resistance (AMR)↗

PubMedDate not supplied

Antimicrobial agents from higher plants. The antimicrobially inactive components of Ptelea trifoliata L.

From the weakly antibacterial non-quaternary alkaloidal fractions from Ptelea trifoliata L. (Rutaceae), ten tertiary quinol-2-one and quinol-4-one alkaloids were isolated and identified. In addition, beta-sitosterol, beta-sitosteryl-beta-D-glucoside and bergapten were isolated. None of these compounds possessed perceptible antimicrobial activity. The weak antimicrobial activity of the neutral and alkaloidal fractions was traced to small amounts of pteleatinium chloride which had not been completely separated by bulk processes. Alkaloids previously known to be present in P. trifoliata which were found in this study ptelefoline methyl ether, pteleine and skimmianine. Alkaloids previously known but new to this plant were lunidoine and isomaculasidine. Alkaloids newly found in nature were neohydroxylunine, hydroxylunidonine, 6-methoxylunidoine, 6-methoxylunineand 6-methoxy-hydroxylunidine. The structure of the latter three bases is proposed tentatively.

Alkaloids↗

PubMedDate not supplied

Antimicrobial properties of some West African medicinal plants iv. Antimicrobial activity of xylopic acid and other constituente of the fruits of Xylopia aethiopica (Annonaceae).

Xylopic acid and four other isolates from the fresh ripe fruits of Xylopia aethiopica a common ingredient in several Ghanaian folklore medicines and foods, have been examined for antimicrobial activity against five micro-organisms, Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa and Candida albicans. Xylopic acid and two other diterpene isolates were found to have antimicrobial properties.

Anti-Bacterial Agents↗

PubMed1976

Antimicrobial agents: synthesis and antimicrobial activity of new aryloxyalkyl esters of p-hydroxybenzoic acid.

Several new aryloxyalkyl esters of p-hydroxybenzoic acid were synthesized and screened for in vitro antimicrobial activity. Although a few compounds showed low antifungal activity, many possessed appreciable in vitro antibacterial activity. However, none of these compounds was active against Mycobacterium tuberculosis (H37Rv).

Anti-Bacterial Agents↗

PubMed1977

Antimicrobial systems of the surgical wound. II. Detection of antimicrobial protein in cell-free wound fluid.

Human wound fluid contains heat-stable proteins with moderate antibacterial activity against Staphylococcus aureus and Escherichia coli, and different heat-labile proteins with antibacterial activity against E coli. Blood serum also contains heat-labile antibacterial substances, but little heat-stable activity against Staphylococcus aureus. Both blood serum and wound fluid have bacteriostatic activity against S epidermidis, and early growth of Streptococcus fecalis occurs in serum and wound fluids. The concentration or activity of antimicrobial proteins increases during the first week in the fresh wound and then decreases as the wound matures.

Blood Bactericidal Activity↗

PubMed1978

Lactoperoxidase, peroxide, thiocyanate antimicrobial system: correlation of sulfhydryl oxidation with antimicrobial action.

The antimicrobial activity of the lactoperoxidase, peroxide, thiocyanate system against Escherichia coli was directly related to the oxidation of bacterial sulfhydryls. Lactoperoxidase catalyzed the oxidation of thiocyanate, which resulted in the accumulation of hypothiocyanite ion, OSCN-. A portion of the bacterial sulfhydryls were oxidized by OSCN- to yield sulfenic acid and sulfenyl thiocyanate derivatives. The remaining sulfhydryls were not oxidized, although OSCN- was present in large excess. The oxidation of sulfhydryls to sulfenyl derivatives inhibited bacterial respiration. This inhibition could be reversed by adding sulfhydryl compounds to reduce the sulfenyl derivatives and the excess OSCN-. Also, this inhibition could be reversed by washing the cells so as to remove the excess unreacted OSCN-. After washing, the bacteria underwent a time-dependent recovery of their sulfhydryl content. This recovery resulted in recovery of the ability to respire. The inhibited cells were viable if diluted and plated shortly after the incubation with the lactoperoxidase, peroxide, thiocyanate system. On the other hand, long-term incubation in the presence of the excess OSCN- resulted in loss of viability. Also, the inhibition of respiration became irreversible. During this long-term incubation, the excess OSCN- was consumed and the sulfenyl derivatives disappeared.

Dithiothreitol↗

PubMed1977

Prophylactic antimicrobial drug therapy at five London teaching hospitals. A report by the Study Group on the Use of Antimicrobial Drugs.

We report some findings of a survey of antimicrobial prophylaxis in 5 London teaching hospitals. It is practised predominantly in surgical patients, both before and after operations, penicillins being by far the commonest drugs. Striking differences were found, particularly in the duration of treatment in different hospitals in the same specialty, and also between consultants in the same hospital. The findings raise important questions that need to be answered by clinical trials.

Administration, Oral↗

PubMed1978