1
|
Lach J, Krupińska M, Mikołajczyk A, Strapagiel D, Stączek P, Matera-Witkiewicz A. Novel Antimicrobial Peptides from Saline Environments Active against E. faecalis and S. aureus: Identification, Characterisation and Potential Usage. Int J Mol Sci 2023; 24:11787. [PMID: 37511545 PMCID: PMC10380286 DOI: 10.3390/ijms241411787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 07/16/2023] [Accepted: 07/19/2023] [Indexed: 07/30/2023] Open
Abstract
Microorganisms inhabiting saline environments have been known for decades as producers of many valuable bioproducts. These substances include antimicrobial peptides (AMPs), the most recognizable of which are halocins produced by halophilic Archaea. As agents with a different modes of action from that of most conventionally used antibiotics, usually associated with an increase in the permeability of the cell membrane as a result of a formation of channels and pores, AMPs are a currently promising object of research focused on the investigation of antibiotics with non-standard modes of action. The aim of this study was to investigate antimicrobial activity against multidrug-resistant human pathogens of three peptides, which were synthetised based on sequences identified in metagenomes from saline environments. The investigations were performed against Enterococcus faecalis, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Escherichia coli and Candida albicans. Subsequently, the cytotoxicity and haemolytic properties of the tested peptides were verified. An in silico analysis of the interaction of the tested peptides with molecular targets for reference antibiotics was also carried out in order to verify whether or not they can act in a similar way. The P1 peptide manifested the growth inhibition of E. faecalis at a MIC50 of 32 µg/mL and the P3 peptide at a MIC50 of 32 µg/mL was shown to inhibit the growth of both E. faecalis and S. aureus. Furthermore, the P1 and P3 peptides were shown to have no cytotoxic or haemolytic activity against human cells.
Collapse
Affiliation(s)
- Jakub Lach
- Department of Molecular Microbiology, Faculty of Biology and Environmental Protection, University of Lodz, 90-237 Lodz, Poland
- Biobank Lab, Department of Oncobiology and Epigenetics, Faculty of Biology and Environmental Protection, University of Lodz, 90-235 Lodz, Poland
| | - Magdalena Krupińska
- Screening of Biological Activity Assays and Collection of Biological Material Laboratory, Wroclaw Medical University Biobank, Faculty of Pharmacy, Wroclaw Medical University, 50-556 Wroclaw, Poland
| | - Aleksandra Mikołajczyk
- Screening of Biological Activity Assays and Collection of Biological Material Laboratory, Wroclaw Medical University Biobank, Faculty of Pharmacy, Wroclaw Medical University, 50-556 Wroclaw, Poland
| | - Dominik Strapagiel
- Biobank Lab, Department of Oncobiology and Epigenetics, Faculty of Biology and Environmental Protection, University of Lodz, 90-235 Lodz, Poland
| | - Paweł Stączek
- Department of Molecular Microbiology, Faculty of Biology and Environmental Protection, University of Lodz, 90-237 Lodz, Poland
| | - Agnieszka Matera-Witkiewicz
- Screening of Biological Activity Assays and Collection of Biological Material Laboratory, Wroclaw Medical University Biobank, Faculty of Pharmacy, Wroclaw Medical University, 50-556 Wroclaw, Poland
| |
Collapse
|
2
|
Miranda CD, Concha C, Godoy FA, Lee MR. Aquatic Environments as Hotspots of Transferable Low-Level Quinolone Resistance and Their Potential Contribution to High-Level Quinolone Resistance. Antibiotics (Basel) 2022; 11:1487. [PMID: 36358142 PMCID: PMC9687057 DOI: 10.3390/antibiotics11111487] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Revised: 10/01/2022] [Accepted: 10/04/2022] [Indexed: 08/27/2023] Open
Abstract
The disposal of antibiotics in the aquatic environment favors the selection of bacteria exhibiting antibiotic resistance mechanisms. Quinolones are bactericidal antimicrobials extensively used in both human and animal medicine. Some of the quinolone-resistance mechanisms are encoded by different bacterial genes, whereas others are the result of mutations in the enzymes on which those antibiotics act. The worldwide occurrence of quinolone resistance genes in aquatic environments has been widely reported, particularly in areas impacted by urban discharges. The most commonly reported quinolone resistance gene, qnr, encodes for the Qnr proteins that protect DNA gyrase and topoisomerase IV from quinolone activity. It is important to note that low-level resistance usually constitutes the first step in the development of high-level resistance, because bacteria carrying these genes have an adaptive advantage compared to the highly susceptible bacterial population in environments with low concentrations of this antimicrobial group. In addition, these genes can act additively with chromosomal mutations in the sequences of the target proteins of quinolones leading to high-level quinolone resistance. The occurrence of qnr genes in aquatic environments is most probably caused by the release of bacteria carrying these genes through anthropogenic pollution and maintained by the selective activity of antimicrobial residues discharged into these environments. This increase in the levels of quinolone resistance has consequences both in clinical settings and the wider aquatic environment, where there is an increased exposure risk to the general population, representing a significant threat to the efficacy of quinolone-based human and animal therapies. In this review the potential role of aquatic environments as reservoirs of the qnr genes, their activity in reducing the susceptibility to various quinolones, and the possible ways these genes contribute to the acquisition and spread of high-level resistance to quinolones will be discussed.
Collapse
Affiliation(s)
- Claudio D. Miranda
- Laboratorio de Patobiología Acuática, Departamento de Acuicultura, Universidad Católica del Norte, Coquimbo 1780000, Chile
| | - Christopher Concha
- Laboratorio de Patobiología Acuática, Departamento de Acuicultura, Universidad Católica del Norte, Coquimbo 1780000, Chile
| | - Félix A. Godoy
- Centro i~mar, Universidad de Los Lagos, Puerto Montt 5480000, Chile
| | - Matthew R. Lee
- Centro i~mar, Universidad de Los Lagos, Puerto Montt 5480000, Chile
| |
Collapse
|
3
|
Kanth S, Puttaiahgowda YM. CURRENT STATE AND FUTURE PERSPECTIVES OF STARCH DERIVATIVES AND THEIR BLENDS AS ANTIMICROBIAL MATERIALS. STARCH-STARKE 2022. [DOI: 10.1002/star.202200001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Shreya Kanth
- Department of Chemistry Manipal Institute of Technology Manipal Academy of Higher Education Manipal 576104 India
| | - Yashoda Malgar Puttaiahgowda
- Department of Chemistry Manipal Institute of Technology Manipal Academy of Higher Education Manipal 576104 India
| |
Collapse
|
4
|
Kosikowska U, Stec J, Andrzejczuk S, Mendrycka M, Pietras-Ożga D, Stępień-Pyśniak D. Plasmid-Mediated Fluoroquinolone Resistance Genes in Quinolone-Susceptible Aeromonas spp. Phenotypes Isolated From Recreational Surface Freshwater Reservoir. Front Cell Infect Microbiol 2022; 12:885360. [PMID: 35646727 PMCID: PMC9132129 DOI: 10.3389/fcimb.2022.885360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 03/24/2022] [Indexed: 11/13/2022] Open
Abstract
Aeromonas spp. are recognized as opportunistic pathogens causing diseases. Infections in humans can result mainly in gastrointestinal and wound diseases with or without progression to septicemia. Although Aeromonas spp. are not known uropathogens and they rarely cause urinary tract infection, we hypothesize that the presence of these bacteria in the water and the contact during, e.g., recreational and bathing activity can create the conditions for the colonization of the human body and may result to diseases in various locations, including the urinary tract. Our study presents the occurrence of aeromonad fluoroquinolone-susceptible phenotypes with the presence of plasmid-mediated fluoroquinolone resistance (PMQR) genes in a natural freshwater reservoir occasionally used for recreational activities. Sixty-nine isolates collected during the bathing period were identified by mass spectrometry and screened for the presence of fluoroquinolone-resistant phenotypes and genotypes. Fluoroquinolone susceptibility was determined as minimal inhibitory concentration values. PMQR qnr genes were detected by PCR. Isolates comprising eight species, namely, mainly Aeromonas veronii (50.7% isolates) and Aeromonas media (24.6% isolates) and rarely Aeromonas eucrenophila, Aeromonas caviae, Aeromonas bestiarum, Aeromonas ichthiosmia, and Aeromonas hydrophila, were selected. All isolates were phenotypically susceptible either to ciprofloxacin or levofloxacin. Unexpectedly, at least one to three of the PMQR genes were detected in 42.0% of the fluoroquinolone-susceptible Aeromonas spp. phenotypes. Mainly the qnrS (34.8% isolates) and qnrA (14.5% isolates) determinants were detected. In conclusion, the freshwater reservoir occasionally used for bathing was tainted with aeromonads, with a high occurrence of opportunistic pathogens such as A. veronii and A. media. MALDI‐TOF MS is a powerful technique for aeromonad identification. Our data reveals the mismatch phenomenon between fluoroquinolone-susceptible aeromonad phenotypes and the presence of plasmid-mediated qnr resistance genes. It suggests that phenotypically susceptible bacteria might be a potential source for the storage and transmission of these genes. The exposure during, e.g., a recreational activity may create the potential risk for causing infections, both diagnostically and therapeutically difficult, after expressing the resistance genes and quinolone-resistant strain selection.
Collapse
Affiliation(s)
- Urszula Kosikowska
- Department of Pharmaceutical Microbiology, Medical University of Lublin, Lublin, Poland
- *Correspondence: Urszula Kosikowska,
| | - Joanna Stec
- Department of Pharmaceutical Microbiology, Medical University of Lublin, Lublin, Poland
| | - Sylwia Andrzejczuk
- Department of Pharmaceutical Microbiology, Medical University of Lublin, Lublin, Poland
| | - Mariola Mendrycka
- Faculty of Medical Sciences and Health Sciences, Kazimierz Pulaski University of Technology and Humanities in Radom, Radom, Poland
| | - Dorota Pietras-Ożga
- Department of Epizootiology and Clinic of Infectious Diseases, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, Lublin, Poland
| | - Dagmara Stępień-Pyśniak
- Department of Veterinary Prevention and Avian Diseases, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, Lublin, Poland
| |
Collapse
|
5
|
Shao C, Li C, Zhang C, Ni Z, Liu X, Wang Y. Novel synthesis of orange-red emitting copper nanoclusters stabilized by methionine as a fluorescent probe for norfloxacin sensing. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2020; 236:118334. [PMID: 32305833 DOI: 10.1016/j.saa.2020.118334] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Revised: 03/19/2020] [Accepted: 03/31/2020] [Indexed: 06/11/2023]
Abstract
In the present work, we report a novel chemical approach for the synthesis of orange-red emitting copper nanoclusters (Cu NCs) using L-methionine as stabilizing agent at room temperature for the first time. The synthetic route is facile, economical and viable. The methionine stabilized copper nanoclusters (Cu NCs/Met) were thoroughly characterized by TEM, FT-IR, XPS, UV-Vis, steady state and transient fluorescence spectroscopy. The results show the synthesized Cu NCs/Met with a fluorescence quantum yield of 4.37% possessed high stability and excellent optical features such as large Stokes shift and long fluorescence lifetime (8.3 μs). Significantly, the fluorescence intensity of Cu NCs/Met could be efficiently quenched by norfloxacin (NOR) pharmaceutical. A fast and cost-effective NOR sensor was proposed employing Cu NCs/Met as the fluorescent nanoprobe, and the quenching mechanisms were attributed to inner filter effect and agglomeration-induced quenching. The developed sensor exhibited a high sensitivity and selectivity towards NOR in a wide linear range from 0.05 to 250 μM with a detection limit as low as 17 nM. Moreover, the practicability of the developed NOR sensor for real sample assay was validated with satisfactory recoveries, indicating this sensing platform with great potential for label-free pharmaceutical detection in complex systems.
Collapse
Affiliation(s)
- Congying Shao
- College of Chemistry and Materials Science/Information College, Huaibei Normal University, Huaibei, Anhui 235000, China.
| | - Chunbo Li
- College of Chemistry and Materials Science/Information College, Huaibei Normal University, Huaibei, Anhui 235000, China
| | - Cheng Zhang
- College of Chemistry and Materials Science/Information College, Huaibei Normal University, Huaibei, Anhui 235000, China
| | - Zheng Ni
- College of Chemistry and Materials Science/Information College, Huaibei Normal University, Huaibei, Anhui 235000, China
| | - Xianhu Liu
- College of Chemistry and Materials Science/Information College, Huaibei Normal University, Huaibei, Anhui 235000, China
| | - Yongxiang Wang
- College of Chemistry and Materials Science/Information College, Huaibei Normal University, Huaibei, Anhui 235000, China
| |
Collapse
|
6
|
Elokil AA, Abouelezz KF, Ahmad HI, Pan Y, Li S. Investigation of the Impacts of Antibiotic Exposure on the Diversity of the Gut Microbiota in Chicks. Animals (Basel) 2020; 10:ani10050896. [PMID: 32455745 PMCID: PMC7278382 DOI: 10.3390/ani10050896] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 05/15/2020] [Accepted: 05/18/2020] [Indexed: 12/12/2022] Open
Abstract
Simple Summary Broad-spectrum antibiotics have been a cornerstone in the treatment of bacterial diseases. However, growing evidence suggests that antibiotics have effects on host-associated gut microbiota communities. In this study, we report persistent significant changes in the abundance of gut microbiota and their functional metabolite pathways in chickens due to enrofloxacin and diclazuril exposure. These changes may affect the taxonomic, genomic, and functional capacity of the chicken gut microbiota, reducing bacterial diversity while expanding and collapsing membership of specific indigenous taxa. Understanding the biology of competitive exclusion of adaptive functions during antibiotic exposure in the gut may inform the design of new strategies to treat infections, while preserving the ecology of chicken-beneficial constituents. Abstract The dynamic microbiota in chickens can be affected by exposure to antibiotics, which may alter the composition and substrate availability of functional pathways. Here, 120 Jing Hong chicks at 30 days of age were randomly divided into four treatments totaling seven experimental groups: control chicks not exposed to antibiotics; and chicks exposed to enrofloxacin, diclazuril, and their mixture at 1:1 for 14 days and then not exposed for a withdrawal period of 15 days. Fecal samples were collected from the 7 groups at 8 time-points (exposure to 4 antibiotics and 4 withdrawal periods) to perform in-depth 16S rRNA sequencing of the gut microbiota. Taxon-independent analysis showed that the groups had significantly distinct microbial compositions (p < 0.01). Based on the microbial composition, as compared with the control group, the abundances of the phyla Firmicutes, Actinobacteria, Thermi, and Verrucomicrobia, as well as the families Lactobacillus, Lactococcus, S24-7, and Corynebacterium, were decreased in the antibiotic-exposed chicks (p < 0.01). Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) analyses revealed significant differences in microbiota metabolite pathways due to the genera of the antibiotic-responsive microbes (p < 0.01), especially the pathways relating to cell growth and death, immune system diseases, carbohydrate metabolism, and nucleotide metabolism. Oral treatment with enrofloxacin, diclazuril, and their mixture modified the gut microbiota composition and the microbial metabolic profiles in chickens, with persistent effects (during the withdrawal period) that prevented the return to the original community and led to the formation of a new community.
Collapse
Affiliation(s)
- Abdelmotaleb A. Elokil
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (A.A.E.); (Y.P.)
- Department of Animal Production, Faculty of Agriculture, Benha University, Moshtohor 13736, Egypt
| | - Khaled F.M. Abouelezz
- Department of Poultry Production, Faculty of Agriculture, Assiut University, Assiut 71526, Egypt;
| | - Hafiz I. Ahmad
- Department of Livestock Production, University of Veterinary and Animal sciences, Ravi Campus, Pattoki 55300, Pakistan;
| | - Yuanhu Pan
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (A.A.E.); (Y.P.)
| | - Shijun Li
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Animal Science and Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (A.A.E.); (Y.P.)
- Correspondence: ; Tel.: +86-27-8738-7480; Fax: +86-27-8728-0408
| |
Collapse
|
7
|
Sheng H, Huang J, Han Z, Liu M, Lü Z, Zhang Q, Zhang J, Yang J, Cui S, Yang B. Genes and Proteomes Associated With Increased Mutation Frequency and Multidrug Resistance of Naturally Occurring Mismatch Repair-Deficient Salmonella Hypermutators. Front Microbiol 2020; 11:770. [PMID: 32457709 PMCID: PMC7225559 DOI: 10.3389/fmicb.2020.00770] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 03/31/2020] [Indexed: 11/23/2022] Open
Abstract
The emergence of antibiotic-resistant Salmonella through mutations led to mismatch repair (MMR) deficiency that represents a potential hazard to public health. Here, four representative MMR-deficient Salmonella hypermutator strains and Salmonella Typhimurium LT2 were used to comprehensively reveal the influence of MMR deficiency on antibiotic resistance among Salmonella. Our results indicated that the mutation frequency ranged from 3.39 × 10–4 to 5.46 × 10–2 in the hypermutator. Mutation sites in MutS, MutL, MutT, and UvrD of the four hypermutators were all located in the essential and core functional regions. Mutation frequency of the hypermutator was most highly correlated with the extent of mutation in MutS. Mutations in MMR genes (mutS, mutT, mutL, and uvrD) were correlated with increased mutation in antibiotic resistance genes, and the extent of antibiotic resistance was significantly correlated with the number of mutation sites in MutL and in ParC. The number of mutation sites in MMR genes and antibiotic resistance genes exhibited a significant positive correlation with the number of antibiotics resisted and with expression levels of mutS, mutT, and mutL. Compared to Salmonella Typhimurium LT2, a total of 137 differentially expressed and 110 specifically expressed proteins were identified in the four hypermutators. Functional enrichment analysis indicated that the proteins significantly overexpressed in the hypermutators primarily associated with translation and stress response. Interaction network analysis revealed that the ribosome pathway might be a critical factor for high mutation frequency and multidrug resistance in MMR-deficient Salmonella hypermutators. These results help elucidate the mutational dynamics that lead to hypermutation, antibiotic resistance, and activation of stress response pathways in Salmonella.
Collapse
Affiliation(s)
- Huanjing Sheng
- College of Food Science and Engineering, Northwest A&F University, Xianyang, China
| | - Jinling Huang
- College of Food Science and Engineering, Northwest A&F University, Xianyang, China
| | - Zhaoyu Han
- School of Pharmaceutical Sciences, Jiangnan University, Wuxi, China
| | - Mi Liu
- College of Food Science and Engineering, Northwest A&F University, Xianyang, China
| | - Zexun Lü
- College of Food Science and Engineering, Northwest A&F University, Xianyang, China
| | - Qian Zhang
- College of Food Science and Engineering, Northwest A&F University, Xianyang, China
| | - Jinlei Zhang
- College of Food Science and Engineering, Northwest A&F University, Xianyang, China
| | - Jun Yang
- College of Food Science and Engineering, Northwest A&F University, Xianyang, China
| | - Shenghui Cui
- National Institutes for Food and Drug Control, Beijing, China
| | - Baowei Yang
- College of Food Science and Engineering, Northwest A&F University, Xianyang, China
| |
Collapse
|
8
|
Liu K, Huigens RW. Instructive Advances in Chemical Microbiology Inspired by Nature's Diverse Inventory of Molecules. ACS Infect Dis 2020; 6:541-562. [PMID: 31842540 PMCID: PMC7346871 DOI: 10.1021/acsinfecdis.9b00413] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Natural product antibiotics have played an essential role in the treatment of bacterial infection in addition to serving as useful tools to explore the intricate biology of bacteria. Our current arsenal of antibiotics operate through the inhibition of well-defined bacterial targets critical for replication and growth. Pathogenic bacteria effectively utilize a diversity of mechanisms that lead to acquired resistance and/or innate tolerance toward antibiotic therapies, which can result in devastating consequences to human life. Several research groups have established innovative programs that work at the chemistry-biology interface to develop new molecules that aim to define and address concerns related to antibiotic resistance and tolerance. In this Review, we present recent progress by select research groups that highlight a diversity of integrated chemical biology and medicinal chemistry approaches aimed at the development and utilization of chemical tools that have led to promising new microbiological insights that may lead to significant clinical advances regarding the treatment of pathogenic bacteria.
Collapse
Affiliation(s)
- Ke Liu
- 1345 Center Drive, Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), College of Pharmacy, University of Florida, Gainesville, Florida 32610, United States
| | - Robert W. Huigens
- 1345 Center Drive, Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), College of Pharmacy, University of Florida, Gainesville, Florida 32610, United States
| |
Collapse
|
9
|
Green synthesis of hydrolyzed starch–chitosan nano-composite as drug delivery system to gram negative bacteria. ACTA ACUST UNITED AC 2019. [DOI: 10.1016/j.enmm.2019.100252] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
10
|
Abouelhassan Y, Garrison AT, Yang H, Chávez-Riveros A, Burch GM, Huigens RW. Recent Progress in Natural-Product-Inspired Programs Aimed To Address Antibiotic Resistance and Tolerance. J Med Chem 2019; 62:7618-7642. [PMID: 30951303 DOI: 10.1021/acs.jmedchem.9b00370] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Bacteria utilize multiple mechanisms that enable them to gain or acquire resistance to antibiotic therapies during the treatment of infections. In addition, bacteria form biofilms which are surface-attached communities of enriched populations containing persister cells encased within a protective extracellular matrix of biomolecules, leading to chronic and recurring antibiotic-tolerant infections. Antibiotic resistance and tolerance are major global problems that require innovative therapeutic strategies to address the challenges associated with pathogenic bacteria. Historically, natural products have played a critical role in bringing new therapies to the clinic to treat life-threatening bacterial infections. This Perspective provides an overview of antibiotic resistance and tolerance and highlights recent advances (chemistry, biology, drug discovery, and development) from various research programs involved in the discovery of new antibacterial agents inspired by a diverse series of natural product antibiotics.
Collapse
Affiliation(s)
- Yasmeen Abouelhassan
- Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), College of Pharmacy , University of Florida , Gainesville , Florida 32610 , United States
| | - Aaron T Garrison
- Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), College of Pharmacy , University of Florida , Gainesville , Florida 32610 , United States
| | - Hongfen Yang
- Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), College of Pharmacy , University of Florida , Gainesville , Florida 32610 , United States
| | - Alejandra Chávez-Riveros
- Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), College of Pharmacy , University of Florida , Gainesville , Florida 32610 , United States
| | - Gena M Burch
- Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), College of Pharmacy , University of Florida , Gainesville , Florida 32610 , United States
| | - Robert W Huigens
- Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development (CNPD3), College of Pharmacy , University of Florida , Gainesville , Florida 32610 , United States
| |
Collapse
|
11
|
Lu W, Jiao Y, Gao Y, Qiao J, Mozneb M, Shuang S, Dong C, Li CZ. Bright Yellow Fluorescent Carbon Dots as a Multifunctional Sensing Platform for the Label-Free Detection of Fluoroquinolones and Histidine. ACS APPLIED MATERIALS & INTERFACES 2018; 10:42915-42924. [PMID: 30412373 DOI: 10.1021/acsami.8b16710] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Owing to their diverse properties, fluorescent carbon dots (CDs) have attracted more attention and present enormous potential in development of sensors, bioimaging, drug delivery, microfluidics, photodynamic therapy, light emitting diode, and so forth. Herein, a multifunctional sensing platform based on bright yellow fluorescent CDs (Y-CDs) was designed for the label-free detection of fluoroquinolones (FQs) and histidine (His). The Y-CDs with superior optical and biological merits including high chemical stability, good biocompatibility, and low cytotoxicity were simply synthesized via one-step hydrothermal treatment of o-phenylenediamine ( o-PD) and 4-aminobutyric acid (GABA). The Y-CDs can be utilized to directly monitor the amount of FQs based on fluorescence static quenching owing to the specific interaction between FQs and Y-CDs. Then, the fluorescence of this system can be effectively recovered upon addition of His. The multifunctional sensing platform exhibited high sensitivity and selectivity toward three kinds of FQs and His with low detection limits of 17-67 and 35 nM, respectively. Benefiting from these outstanding characters, the Y-CDs were successfully employed for trace detection of FQs in real samples such as antibiotic tablets and milk products. Furthermore, the probe was also extended to cellular imaging. All of the above prove that this multifunctional sensing platform presents great prospect in multiple applications such as biosensing, biomedicine, disease diagnosis, and environmental monitoring.
Collapse
Affiliation(s)
- Wenjing Lu
- Institute of Environmental Science, and School of Chemistry and Chemical Engineering , Shanxi University , Taiyuan 030006 , China
- Nanobioengineering/Bioelectronics Laboratory, and Department of Biomedical Engineering , Florida International University , Miami 33174 , United States
| | - Yuan Jiao
- Institute of Environmental Science, and School of Chemistry and Chemical Engineering , Shanxi University , Taiyuan 030006 , China
| | - Yifang Gao
- Institute of Environmental Science, and School of Chemistry and Chemical Engineering , Shanxi University , Taiyuan 030006 , China
| | - Jie Qiao
- Nanobioengineering/Bioelectronics Laboratory, and Department of Biomedical Engineering , Florida International University , Miami 33174 , United States
- School of Basic Medical Sciences , Shanxi Medical University , Taiyuan 030001 , China
| | - Maedeh Mozneb
- Nanobioengineering/Bioelectronics Laboratory, and Department of Biomedical Engineering , Florida International University , Miami 33174 , United States
| | - Shaomin Shuang
- Institute of Environmental Science, and School of Chemistry and Chemical Engineering , Shanxi University , Taiyuan 030006 , China
| | - Chuan Dong
- Institute of Environmental Science, and School of Chemistry and Chemical Engineering , Shanxi University , Taiyuan 030006 , China
| | - Chen-Zhong Li
- Nanobioengineering/Bioelectronics Laboratory, and Department of Biomedical Engineering , Florida International University , Miami 33174 , United States
| |
Collapse
|
12
|
Predictors of fluoroquinolone-resistant bacteria in the rectal vault of men undergoing prostate biopsy. Prostate Cancer Prostatic Dis 2018; 22:268-275. [PMID: 30279581 DOI: 10.1038/s41391-018-0092-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 08/19/2018] [Accepted: 08/25/2018] [Indexed: 11/08/2022]
Abstract
IMPORTANCE Fluoroquinolone (FQ)-resistant rectal vault flora is associated with infectious complications in men undergoing transrectal ultrasound-guided prostate needle biopsy (TRUS-PNB). OBJECTIVE To determine the patient factors that predict FQ-resistant rectal cultures in men who are undergoing transrectal ultrasound-guided prostate needle biopsy. METHODS An IRB approved retrospective review of 6183 consecutive men who had undergone a rectal swab culture in preparation for TRUS-PNB between January 2013 and December 2014 was performed. Multivariable logistic regression was used to determine the clinical and demographic factors associated with FQ-resistant Enterobacteriaceae in the rectal vault. RESULTS Of the 6179 rectal swabs analyzed, 4842 (78%) were FQ-sensitive, and 1337 (22%) were FQ-resistant. On univariable analysis, increasing age, prior TRUS-PNB, higher number of biopsy cores obtained, diabetes mellitus, antimicrobial use within the past 6 months and non-Caucasian race were predictors of FQ-resistance (all p < 0.05). Men with FQ-resistant cultures were more likely to have benign pathology on TRUS-PNB (p = 0.004). On multivariable analysis, increasing patient age (OR = 1.01/year [1.00-1.02]), use of antimicrobials in the last 6 months (OR = 2.85[2.18-3.72]), African American (OR = 1.99 [1.66-2.37]), Asian (OR = 3.39 [2.63-4.37]), and Hispanic (OR = 2.10 [1.72-2.55]) races were independently associated with FQ-resistant rectal cultures. The overall infectious rate was 1.1% (56/5214) and the sepsis rate was 0.46% (24/5214). The infection rate in the FQ-resistant group was 3.9% (43/1107) compared to FQ-sensitive group 0.3% (13/4107), p < 0.001. CONCLUSION In this cohort, increasing age, recent antimicrobial-use, and non-Caucasian race were independent predictors of FQ-resistance in the rectal vault. As FQ-resistance is associated with infectious complications from transrectal ultrasound-guided prostate needle biopsy, understanding risk factors may assist infection control efforts.
Collapse
|
13
|
Gui R, Bu X, He W, Jin H. Ratiometric fluorescence, solution-phase and filter-paper visualization detection of ciprofloxacin based on dual-emitting carbon dot/silicon dot hybrids. NEW J CHEM 2018. [DOI: 10.1039/c8nj03788d] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This study demonstrates the ratiometric fluorescence, solution-phase and filter-paper visual detection of ciprofloxacin based on dual-emitting carbon dot/silicon dot hybrids.
Collapse
Affiliation(s)
- Rijun Gui
- College of Chemistry and Chemical Engineering
- Shandong Sino-Japanese Center for Collaborative Research of Carbon Nanomaterials
- Laboratory of Fiber Materials and Modern Textile
- The Growing Base for State Key Laboratory
- Qingdao University
| | - Xiangning Bu
- College of Chemistry and Chemical Engineering
- Shandong Sino-Japanese Center for Collaborative Research of Carbon Nanomaterials
- Laboratory of Fiber Materials and Modern Textile
- The Growing Base for State Key Laboratory
- Qingdao University
| | - Weijie He
- College of Chemistry and Chemical Engineering
- Shandong Sino-Japanese Center for Collaborative Research of Carbon Nanomaterials
- Laboratory of Fiber Materials and Modern Textile
- The Growing Base for State Key Laboratory
- Qingdao University
| | - Hui Jin
- College of Chemistry and Chemical Engineering
- Shandong Sino-Japanese Center for Collaborative Research of Carbon Nanomaterials
- Laboratory of Fiber Materials and Modern Textile
- The Growing Base for State Key Laboratory
- Qingdao University
| |
Collapse
|
14
|
Efficacy of Ceftriaxone, Cefepime, Doxycycline, Ciprofloxacin, and Combination Therapy for Vibrio vulnificus Foodborne Septicemia. Antimicrob Agents Chemother 2017; 61:AAC.01106-17. [PMID: 28971862 DOI: 10.1128/aac.01106-17] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 09/23/2017] [Indexed: 12/17/2022] Open
Abstract
Foodborne Vibrio vulnificus infections are associated with higher rates of sepsis and mortality than wound infections; however, antibiotic efficacy studies have not been performed in foodborne infection models. The efficacies of ceftriaxone, cefepime, doxycycline, ciprofloxacin, and combination therapy were assessed in V. vulnificus intestinal infection in mice in order to model foodborne infections. In accordance with prior studies of cefotaxime, cefepime was synergistic with doxycycline and ciprofloxacin in vitro; combination therapy significantly decreased bacterial growth, by ≥2 log10 units, from that with antibiotic monotherapy (P < 0.01). In vivo, survival rates in the ceftriaxone (50%), doxycycline (79%), and ciprofloxacin (80%) groups were significantly higher than those in the control group (0%) (P < 0.0001). Survival was significantly higher with ceftriaxone-doxycycline (91%) or ceftriaxone-ciprofloxacin (100%) therapy than with ceftriaxone (50%) (P ≤ 0.05). Survival with cefepime-doxycycline (96%) or cefepime-ciprofloxacin (90%) therapy was significantly higher than that with cefepime alone (20%) (P < 0.001). There was no difference in survival between the combination therapy groups. Thus, we conclude that combination therapy was the most effective treatment for foodborne V. vulnificus septicemia. In a septic patient with a recent ingestion of raw seafood, cefepime in combination with doxycycline or ciprofloxacin should be initiated for coverage of resistant Gram-negative organisms and V. vulnificus pending a microbiological diagnosis. Once a diagnosis of foodborne V. vulnificus septicemia is established, treatment can safely transition to ceftriaxone in combination with doxycycline or ciprofloxacin.
Collapse
|
15
|
Meng Y, Cubillos J, Borch M, Messing EM, Gentile D, Joseph JV, Rashid H, Kukreja JB. Antibiogram Directed Prophylaxis for Transrectal Prostate Biopsy: An Application of Recommendations in the Setting of High Fluoroquinolone Escherichia coli Resistance. UROLOGY PRACTICE 2017. [DOI: 10.1016/j.urpr.2016.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Yifan Meng
- School of Medicine and Dentistry, University of Rochester Medical Center, Rochester, New York
| | - Jimena Cubillos
- Department of Urology, Strong Memorial Hospital, University of Rochester Medical Center, Rochester, New York
| | - Marianne Borch
- Department of Urology, Strong Memorial Hospital, University of Rochester Medical Center, Rochester, New York
| | - Edward M. Messing
- Department of Urology, Strong Memorial Hospital, University of Rochester Medical Center, Rochester, New York
| | - David Gentile
- Department of Urology, Strong Memorial Hospital, University of Rochester Medical Center, Rochester, New York
| | - Jean V. Joseph
- Department of Urology, Strong Memorial Hospital, University of Rochester Medical Center, Rochester, New York
| | - Hani Rashid
- Department of Urology, Strong Memorial Hospital, University of Rochester Medical Center, Rochester, New York
| | - Janet Baack Kukreja
- School of Medicine and Dentistry, University of Rochester Medical Center, Rochester, New York
- Department of Urology, Strong Memorial Hospital, University of Rochester Medical Center, Rochester, New York
| |
Collapse
|
16
|
Zhang CZ, Ren SQ, Chang MX, Chen PX, Ding HZ, Jiang HX. Resistance mechanisms and fitness of Salmonella Typhimurium and Salmonella Enteritidis mutants evolved under selection with ciprofloxacin in vitro. Sci Rep 2017; 7:9113. [PMID: 28831084 PMCID: PMC5567280 DOI: 10.1038/s41598-017-09151-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Accepted: 07/24/2017] [Indexed: 12/02/2022] Open
Abstract
The aim of this study was to investigate the difference in resistance mechanisms and fitness of Salmonella Typhimurium (ST) and Salmonella Enteritidis (SE) mutants selected during the evolution of resistance under exposure to increasing ciprofloxacin concentrations in vitro. Mutations in quinolone target genes were screened by PCR. Phenotypic characterization included susceptibility testing by the broth dilution method, investigation of efflux activity and growth rate, and determination of the invasion of human intestinal epithelium cells in vitro. The two Salmonella serotypes exhibited differences in target gene mutations and efflux pump gene expression during the development of resistance. In the parental strains, ST had a competitive advantage over SE. During the development of resistance, initially, the SE strain was more competitive. However, once ciprofloxacin resistance was acquired, ST once again became the more competitive strain. In the absence of bile salts or at 0.1% bile, the growth rate of SE was initially greater than that of ST, but once ciprofloxacin resistance was acquired, ST had higher growth rates. ST strains showed decreased invasion of epithelial cells in 0.1% bile. These data indicate that ciprofloxacin-resistant ST strains are more competitive than ciprofloxacin-resistant SE strains.
Collapse
Affiliation(s)
- Chuan-Zhen Zhang
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University (SCAU), Guangzhou, 510642, China.,National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University (SCAU), Guangzhou, 510642, China
| | - Si-Qi Ren
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University (SCAU), Guangzhou, 510642, China.,National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University (SCAU), Guangzhou, 510642, China
| | - Man-Xia Chang
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University (SCAU), Guangzhou, 510642, China.,National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University (SCAU), Guangzhou, 510642, China
| | - Pin-Xian Chen
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University (SCAU), Guangzhou, 510642, China.,National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University (SCAU), Guangzhou, 510642, China
| | - Huan-Zhong Ding
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University (SCAU), Guangzhou, 510642, China.,National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University (SCAU), Guangzhou, 510642, China
| | - Hong-Xia Jiang
- Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University (SCAU), Guangzhou, 510642, China. .,National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University (SCAU), Guangzhou, 510642, China.
| |
Collapse
|
17
|
Gopal M, Elumalai S, Arumugam S, Durairajpandian V, Kannan MA, Selvam E, Seetharaman S. GyrA ser83 and ParC trp106 Mutations in Salmonella enterica Serovar Typhi Isolated from Typhoid Fever Patients in Tertiary Care Hospital. J Clin Diagn Res 2016; 10:DC14-8. [PMID: 27630841 DOI: 10.7860/jcdr/2016/17677.8153] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 05/01/2016] [Indexed: 11/24/2022]
Abstract
INTRODUCTION Typhoid fever is endemic in India and other developing countries, causing major public health problems with high morbidity and mortality. The resistance of Salmonella enterica serovar Typhi (S. Typhi) towards commonly prescribed antimicrobials is increasing in developing countries. However, there have been several reports of the therapeutic failure of fluoroquinolones in patients with Salmonella infection. Resistance to quinolones/ fluoroquinolones commonly arises due to target site mutation. AIM The present study was planned to analyze mutation in Quinolone Resistance Determining Region (QRDR) of quinolone resistant Salmonella isolates. MATERIALS AND METHODS A total of 133 S. Typhi isolates (blood (n = 131), stool (n=1) and bone marrow aspirate (n=1)) from tertiary care hospitals in Chennai and Puducherry, were included in this study. Minimum Inhibitory Concentrations (MIC) were carried out according to the Clinical Laboratory Standard Institute (CLSI)guidelines 2014. Mutations in gyrA and parC genes were analyzed by PCR-RFLP (Restriction Fragment Length Polymorphism) method followed by DNA sequencing. RESULTS Of the 133 S. Typhi, 99.2% were resistant to nalidixic acid and 21% were resistant to ciprofloxacin by MIC method. 94% of isolates showed Ser 83 mutation in gyrA and 21.8% of isolates showed Trp106-Gly mutation in parC. CONCLUSION Mutations in gyrA and parC genes are highly prevalent among Salmonella species. Irrational use of fluoroquinolones may increase the accumulation of mutations in the DNA gyrase and topoisomerase encoding genes, which lead to the emergence of high level fluoroquinolone-resistant Salmonella strains in future.
Collapse
Affiliation(s)
- Muthu Gopal
- Scientist-C, Model Rural Health Research Unit, National Institute of Epidemiology (ICMR), Primary Health Centre , Nadukallur, Tirunelveli, Tamil Nadu, India
| | - Sathishkumar Elumalai
- Research Scholar, Department of Microbiology, Dr. ALM Post Graduate Institute of Basic Medical Sciences, University of Madras , Taramani, Chennai, India
| | - Suresh Arumugam
- Scientist-C, Centre for Drug Discovery and Development, Sathyabama University , Jeppiaar Nagar, Rajiv Gandhi Road, Chennai, India
| | - Vishnuprabu Durairajpandian
- Scientist, National Hub for Healthcare Instrumentation Development, Centre for Biotechnology, Anna University , Chennai, India
| | - Munirajan Arasambattu Kannan
- Professor, Department of Genetics, Dr. ALM Post Graduate Institute of Basic Medical Sciences, University of Madras , Taramani, Chennai, India
| | - Esthermary Selvam
- Specialist Cum Head of Department of Microbiology, ESIC Hospital , K.K.Nagar, Chennai, Tamil Nadu, India
| | - Srivani Seetharaman
- Assistant Professor, Department of Microbiology, Dr. ALM Post Graduate Institute of Basic Medical Sciences, University of Madras , Taramani, Chennai, India
| |
Collapse
|
18
|
Lyonga EE, Toukam M, Nkenfou C, Gonsu HK, Assoumou MCO, Mesembe MT, Eyoh AB, Ikomey GM, Ndze VN, Koulla-Shiro S. Resistance pattern of enterobacteriaceae isolates from urinary tract infections to selected quinolones in Yaoundé. Pan Afr Med J 2015; 21:105. [PMID: 26327943 PMCID: PMC4546718 DOI: 10.11604/pamj.2015.21.105.5469] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Accepted: 05/15/2015] [Indexed: 11/25/2022] Open
Abstract
Introduction It is estimated that 150 million urinary tract infections (UTIs) occur yearly worldwide, resulting in more than 6 billion dollar in direct healthcare cost. The etiology of UTIs is predictable, with Escherichia coli, an Enterobacteriaceae being the principal pathogen. Quinolones are usually the drug of choice. In this study, we report the resistance pattern of Enterobacteriaceae isolates from UTIs to quinolones among in-patients and out-patients at the Yaoundé Reference Hospital in Cameroon. Methods A cross-sectional descriptive study was carried out for a ten-month period. Consecutive clean-catch mid-stream urine samples were collected from 207 in and out-patients. Identification was done using the Api 20E, and susceptibility testing using the Kirby Bauer's disc diffusion method and the MIC was done using the E-test. Results Out of the 207 isolates, 58(28.0%) were found to be resistant to all the quinolones used in the study. The resistances observed by species were in the order: Enterobacter 4(30.8%); Klebsiella 19(29.7%); Escherichia 25 (29.4%); Proteus 2(11.8%); Serratia 4(25.0%). Quinolone resistance for Escherichia was 42.9% for In-Patients (IP) and 16.3% for Out-Patient (OP) (P-value = 0.006); Klebsiella 35.9% for IP and 20% for OP; Proteus 11.1% for IP and 12.5% for OP; Serratia 18.2% for IP and 40% for OP; Enterobacter 22.2 for IP and 50% for OP. Conclusion High resistance rates to quinolones were observed not only for in-patients but also for out-patients with urinary tract enterobacterial infections. These findings demonstrate the importance of antibiotics susceptibility testing in improving quinolones prescription practices in Cameroon.
Collapse
Affiliation(s)
- Emilia Enjema Lyonga
- Department of Microbiology, Haematology, Parasitology and Infectious Diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaoundé, Cameroon ; Centre for the Study and Control of Communicable Diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaoundé, Cameroon
| | - Michel Toukam
- Department of Microbiology, Haematology, Parasitology and Infectious Diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaoundé, Cameroon
| | - Celine Nkenfou
- Higher Teachers' Training College, University of Yaoundé 1, Yaoundé, Cameroon ; Systems Biology Laboratory, Chantal Biya's International Reference Centre (CBIRC), Yaoundé, Cameroon
| | - Hortense Kamga Gonsu
- Department of Microbiology, Haematology, Parasitology and Infectious Diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaoundé, Cameroon
| | - Marie-Claire Okomo Assoumou
- Department of Microbiology, Haematology, Parasitology and Infectious Diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaoundé, Cameroon ; Centre for the Study and Control of Communicable Diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaoundé, Cameroon
| | - Martha Tongo Mesembe
- Centre for the Study and Control of Communicable Diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaoundé, Cameroon
| | - Agnes Bedie Eyoh
- Department of Microbiology, Haematology, Parasitology and Infectious Diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaoundé, Cameroon ; Centre for the Study and Control of Communicable Diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaoundé, Cameroon
| | - George Mondinde Ikomey
- Department of Microbiology, Haematology, Parasitology and Infectious Diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaoundé, Cameroon ; Centre for the Study and Control of Communicable Diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaoundé, Cameroon
| | - Valantine Ngum Ndze
- Department of Microbiology, Haematology, Parasitology and Infectious Diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaoundé, Cameroon
| | - Sinata Koulla-Shiro
- Department of Microbiology, Haematology, Parasitology and Infectious Diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaoundé, Cameroon
| |
Collapse
|
19
|
Jia W, Wang J, Xu H, Li G. Resistance of Stenotrophomonas maltophilia to Fluoroquinolones: Prevalence in a University Hospital and Possible Mechanisms. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2015; 12:5177-95. [PMID: 25985315 PMCID: PMC4454961 DOI: 10.3390/ijerph120505177] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 05/04/2015] [Indexed: 12/23/2022]
Abstract
Objective: The purpose of this study was to investigate the clinical distribution and genotyping of Stenotrophomonas maltophilia, its resistance to antimicrobial agents, and the possible mechanisms of this drug resistance. Methods: S. maltophilia isolates were collected from clinical specimens in a university hospital in Northwestern China during the period between 2010 and 2012, and were identified to the species level with a fully automated microbiological system. Antimicrobial susceptibility testing was performed for S. maltophilia with the Kirby-Bauer disc diffusion method. The minimal inhibitory concentrations (MICs) of norfloxacin, ofloxacin, chloramphenicol, minocycline, ceftazidime, levofloxacin and ciprofloxacin against S. maltophilia were assessed using the agar dilution method, and changes in the MIC of norfloxacin, ciprofloxacin and ofloxacin were observed after the addition of reserpine, an efflux pump inhibitor. Fluoroquinolone resistance genes were detected in S. maltophilia using a polymerase chain reaction (PCR) assay, and the expression of efflux pump smeD and smeF genes was determined using a quantitative fluorescent (QF)-PCR assay. Pulsed-field gel electrophoresis (PFGE) was employed to genotype identified S. maltophilia isolates. Results: A total of 426 S. maltophilia strains were isolated from the university hospital from 2010 to 2012, consisting of 10.1% of total non-fermentative bacteria. The prevalence of norfloxacin, ciprofloxacin and ofloxacin resistance was 32.4%, 21.9% and 13.2% in the 114 S. maltophilia isolates collected from 2012, respectively. Following reserpine treatment, 19 S. maltophilia isolates positive for efflux pump were identified, and high expression of smeD and smeF genes was detected in two resistant isolates. gyrA, parC, smeD, smeE and smeF genes were detected in all 114 S. maltophilia isolates, while smqnr gene was found in 25.4% of total isolates. Glu-Lys mutation (GAA-AAA) was detected at the 151th amino acid of the gyrA gene, while Gly-Arg mutation (GGC-CGC) was found at the 37th amino acid of the parC gene. However, no significant difference was observed in the prevalence of gyrA or parC mutation between fluoroquinolone-resistant and -susceptible isolates (p> 0.05). The smqnr gene showed 92% to 99% heterogenicity among the 14 S. maltophilia clinical isolates. PFGE of 29 smqnr gene-positive S. maltophilia clinical isolates revealed 25 PFGE genotypes and 28 subgenotypes. Conclusions: Monitoring the clinical distribution and antimicrobial resistance of S. maltophilia is of great significance for the clinical therapy of bacterial infections. Reserpine is effective to inhibit the active efflux of norfloxacin, ciprofloxacin and ofloxacin on S. maltophilia and reduce MIC of fluoroquinolones against the bacteria. The expression of efflux pump smeD and smeF genes correlates with the resistance of S. maltophilia to fluoroquinolones.
Collapse
Affiliation(s)
- Wei Jia
- Medical Experimental Center, General Hospital of Ningxia Medical University, 804 Shengli Street, Yinchuan City, Ningxia Hui Autonomous Region 750004, China.
| | - Jiayuan Wang
- School of Laboratory Medicine, Ningxia Medical University, 1160 Shengli Street, Yinchuan City, Ningxia Hui Autonomous Region 750004, China.
| | - Haotong Xu
- School of Laboratory Medicine, Ningxia Medical University, 1160 Shengli Street, Yinchuan City, Ningxia Hui Autonomous Region 750004, China.
| | - Gang Li
- Medical Experimental Center, General Hospital of Ningxia Medical University, 804 Shengli Street, Yinchuan City, Ningxia Hui Autonomous Region 750004, China.
| |
Collapse
|
20
|
|
21
|
Xia R, Ren Y, Xu H. Identification of plasmid-mediated quinolone resistance qnr genes in multidrug-resistant Gram-negative bacteria from hospital wastewaters and receiving waters in the Jinan area, China. Microb Drug Resist 2013; 19:446-56. [PMID: 23844849 DOI: 10.1089/mdr.2012.0210] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We investigated the prevalence of plasmid-mediated quinolone resistance (PMQR) qnr genes by the polymerase chain reaction (PCR) in antibiotic-resistant bacteria isolates collected from aquatic environments in Jinan during 2 years (2008.3-2009.11). Genes were identified to variant level by PCR restriction fragment length polymorphism analysis or sequencing. qnrA1, qnrB2, qnrB4, qnrB6, qnrB9, qnrS1, and the new qnrB variant qnrB26 were detected in 31 strains from six genera (Klebsiella spp., Escherichia coli, Enterobacter spp., Proteus spp., Shigella spp., and Citrobacter spp.), four of which contained double qnr genes. Other PMQR genes, aac(6')-Ib-cr and qepA, were found in 12 (38.7%) and 5 (16.1%) of 31 isolates, respectively; while qepA was found in Shigella spp. for the first time. Eight types of β-lactamase genes and eight other types of resistance genes were also present in the 31 qnr-positive isolates. The detection rate for five β-lactamase genes (blaTEM, blaCTX, ampR, blaDHA, and blaSHV) was >45%. Class 1 integrons and complex class 1 integrons were prevalent in these strains, which contained 15 different gene cassette arrays and 5 different insertion sequence common region 1 (ISCR1)-mediated downstream structures. qnrA1, qnrB2, and qnrB6 were present in three ISCR1-mediated downstream structures: qnrA1-ampR, sapA-like-qnrB2, and sdr-qnrB6. We also analyzed the horizontal transferability of PMQR genes and other resistance determinants. The qnr genes and some integrons and resistance genes from 18 (58.1%) of the 31 qnr-positive strains could be transferred to E. coli J53 Azi(R) or E. coli DH5α recipient strains using conjugation or transformation methods. The results showed that a high number of qnr genes were associated with other resistance genes in aquatic environments in Jinan. This suggests that we should avoid over-using antibiotics and monitor aquatic environments to control the spread of antibiotic resistance genes.
Collapse
Affiliation(s)
- Ruirui Xia
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University , Jinan, China
| | | | | |
Collapse
|
22
|
Picozzi S, Ricci C, Gaeta M, Macchi A, Dinang E, Paola G, Tejada M, Costa E, Bozzini G, Casellato S, Carmignani L. Do we really know the prevalence of multi-drug resistant Escherichia coli in the territorial and nosocomial population? Urol Ann 2013; 5:25-9. [PMID: 23662006 PMCID: PMC3643319 DOI: 10.4103/0974-7796.106962] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2011] [Accepted: 01/08/2012] [Indexed: 11/08/2022] Open
Abstract
Introduction: The purpose of this work was to evaluate the prevalence of the Quinolones resistant Escherichia coli and/or ESBL producers in the population of our catchment area and hospital component. Materials and Methods: From January 2008 to December 2010, all data concerning urine cultures in patients with suspected urinary tract infection and/or asymptomatic bacteriuria referring at our center located in the south of Milan were prospectively evaluated. Results: In 2008, 2136 outpatient and 1232 hospital urine cultures were analyzed. The presence of quinolone-resistant strains was 21% at a local level and 53% in hospitals. ESBL-producing strains were isolated in 3.5% of cases at a local level and 20.5% in hospitals. In 2009, 2396 outpatient and 1320 hospital urine cultures were analyzed. The presence of quinolone-resistant strains was 21% at a local level and 46% in hospitals. ESBL-producing strains were isolated in 5.4% of cases at a local level and 20% in hospitals. In 2010, 2601 outpatient and 1717 hospital urine cultures were analyzed. The presence of quinolone-resistant strains was 34% at a local level and 26% in hospitals. ESBL-producing strains were isolated in 6.7% of cases at a local level and 20.6% in hospitals. The multidrug resistance was significantly (P < 0.01) higher in ESBL-positive strains. Conclusion: Due to rising antibiotic resistance among uropathogens, it is important to have knowledge of the organisms causing urinary tract infections and their antibiotic sensitivity patterns. In areas with high prevalence of E. Coli resistance, performing urine culture before every surgical procedure became mandatory, in order to prevent fatal sepsis.
Collapse
Affiliation(s)
- Stefano Picozzi
- Department of Urology, IRCCS Policlinico San Donato, University of Milan, Via Morandi 30, 20097 - San Donato Milanese, Milan, Italy
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Hurley M, Smyth A. Fluoroquinolones in the treatment of bronchopulmonary disease in cystic fibrosis. Ther Adv Respir Dis 2012; 6:363-73. [PMID: 22968160 PMCID: PMC3509170 DOI: 10.1177/1753465812459899] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Fluoroquinolones are commonly used to treat lung infections in patients with cystic fibrosis. These patients are susceptible to lung infection with common bacteria such as Staphylococcus aureus and Haemophilus influenzae, but are also prone to infection by opportunistic bacteria, including Pseudomonas aeruginosa. The good oral bioavailability and broad antimicrobial spectrum of activity, including antipseudomonal properties, make this class of antimicrobial attractive. We review the evidence assessing the use of fluoroquinolones in the context of preventing and eradicating early lung infection and in managing chronic lung infection and pulmonary exacerbations. The safety of fluoroquinolones and the use of newer agents in the class are also discussed.
Collapse
Affiliation(s)
- Matthew Hurley
- Division of Child Health, University of Nottingham, Queens Medical Centre, Nottingham, UK.
| | | |
Collapse
|
24
|
Meng J, Bai H, Jia M, Ma X, Hou Z, Xue X, Zhou Y, Luo X. Restoration of antibiotic susceptibility in fluoroquinolone-resistant Escherichia coli by targeting acrB with antisense phosphorothioate oligonucleotide encapsulated in novel anion liposome. J Antibiot (Tokyo) 2011; 65:129-134. [DOI: 10.1038/ja.2011.125] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
25
|
Analysis of the antimicrobial susceptibility of the ionizing radiation-resistant bacterium Deinococcus radiodurans: implications for bioremediation of radioactive waste. ANN MICROBIOL 2011. [DOI: 10.1007/s13213-011-0281-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
|
26
|
Darehkordi A, Javanmiri M, Ghazi S, Assar S. Synthesis of N-aryl-2,2,2-trifluoroacetimidoyl piperazinylquinolone derivatives and their antibacterial evaluations. J Fluor Chem 2011. [DOI: 10.1016/j.jfluchem.2011.02.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
27
|
Páez PL, Becerra MC, Albesa I. Antioxidative mechanisms protect resistant strains of Staphylococcus aureus against ciprofloxacin oxidative damage. Fundam Clin Pharmacol 2011; 24:771-6. [PMID: 20412315 DOI: 10.1111/j.1472-8206.2009.00806.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The aim of this investigation was to determine whether the antioxidant defences protect resistant strains of Staphylococcus aureus against ciprofloxacin oxidative damage. Reactive oxygen species (ROS) were determined by chemiluminescence and nitric oxide (NO) was assayed by Griess reaction. The accumulation of ciprofloxacin was examined by fluorometry and oxidation of protein, catalase, ferrous reduction antioxidant potency (FRAP), carbonyls and advanced oxidation protein products (AOPP), studied by spectrophotometry. Ciprofloxacin stimulated higher production of ROS and NO in the susceptible strains than in the resistant ones. There was higher accumulation of antibiotic in sensitive strains than in resistant ones, except for the most resistant strain, which accumulated an elevated amount of antibiotic. The FRAP/ciprofloxacin accumulation ratio of the antibiotic was lower in sensitive than in resistant strains. The most resistant strain exhibited the highest FRAP and presented a high catalase activity. There was oxidation of proteins in the presence of ciprofloxacin, with the carbonyl residues increasing in sensitive and resistant S. aureus. The degradation of carbonyls to AOPP in oxidized proteins was higher in the resistant than in sensitive strains. In conclusion, an increase in antioxidant capacity and a rapid oxidation of carbonyls to AOPP contributed to resistance to ciprofloxacin.
Collapse
Affiliation(s)
- Paulina Laura Páez
- Facultad de Ciencias Químicas, Universidad Nacional de Córdoba- Ciudad Universitaria, 5000 Córdoba, Argentina
| | | | | |
Collapse
|
28
|
Cheng TJR, Wu YT, Yang ST, Lo KH, Chen SK, Chen YH, Huang WI, Yuan CH, Guo CW, Huang LY, Chen KT, Shih HW, Cheng YSE, Cheng WC, Wong CH. High-throughput identification of antibacterials against methicillin-resistant Staphylococcus aureus (MRSA) and the transglycosylase. Bioorg Med Chem 2010; 18:8512-29. [PMID: 21075637 DOI: 10.1016/j.bmc.2010.10.036] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2010] [Revised: 10/11/2010] [Accepted: 10/14/2010] [Indexed: 12/01/2022]
Abstract
To identify new transglycosylase inhibitors with potent anti-methicillin-resistant Staphylococcus aureus (MRSA) activities, a high-throughput screening against Staphylococcus aureus was conducted to look for antibacterial cores in our 2M compound library that consists of natural products, proprietary collection, and synthetic molecules. About 3600 hits were identified from the primary screening and the subsequent confirmation resulted in a total of 252 compounds in 84 clusters which showed anti-MRSA activities with MIC values as low as 0.1 μg/ml. Subsequent screening targeting bacterial transglycosylase identified a salicylanilide-based core that inhibited the lipid II polymerization and the moenomycin-binding activities of transglycosylase. Among the collected analogues, potent inhibitors with the IC(50) values below 10 μM against transglycosylase were identified. The non-carbonhydrate scaffold reported in this study suggests a new direction for development of bacterial transglycosylase inhibitors.
Collapse
Affiliation(s)
- Ting-Jen Rachel Cheng
- Genomics Research Center, Academia Sinica, 128 Sec 2 Academia Road, Nankang, Taipei 115, Taiwan. Genomics Research Center, Academia Sinica, 128 Sec 2 Academia Road, Nankang, Taipei 115, Taiwan
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Abstract
Campylobacter is a commensal in poultry, and therefore, poultry and poultry products are major sources of Campylobacter infections in humans. Fluoroquinolones inhibit the growth of Campylobacter and other microorganisms by binding to bacterial DNA gyrase and DNA topoisomerase IV. These enzymes are associated with bacterial transcription, replication, and chromosome condensation and segregation. Selection pressure in the presence of fluoroquinolones rapidly leads to resistance in Campylobacter, due to the selection for mutations in DNA gyrase. Fluoroquinolone-resistant campylobacters have been found in poultry feces and carcasses, and in retail poultry meat products in most areas of the world. In addition, other food animals and the meat products from those animals have been shown contaminated with fluoroquinolone-resistant campylobacters. Even the removal of fluoroquinolones from use in treating animal diseases has not entirely eliminated the presence of resistant Campylobacter jejuni and Campylobacter coli from animals and animal products. Human exposure to Campylobacter infection could be reduced by using strategies that decrease colonization of chickens by the pathogen.
Collapse
Affiliation(s)
- James L Smith
- Microbial Food Safety Unit, Eastern Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, 600 East Mermaid Lane, Wyndmoor, Pennsylvania 19038-8598, USA.
| | | |
Collapse
|
30
|
Behrens-Baumann W, Frank U, Neß T. Rationale Antibiotikatherapie in der Augenheilkunde. Ophthalmologe 2010; 107:323-7. [DOI: 10.1007/s00347-009-2077-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
31
|
Srinivas A, Azad RV, Sharma YR, Kumar A, Satpathy G, Velpandian T. Evaluation of vitreous levels of gatifloxacin after systemic administration in inflamed and non-inflamed eyes. Acta Ophthalmol 2009; 87:648-52. [PMID: 19508273 DOI: 10.1111/j.1755-3768.2008.01323.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE This study aimed to evaluate the human vitreous penetration of gatifloxacin in inflamed and non-inflamed eyes after oral administration. METHODS Vitreous penetration of single-dose (400 mg) oral gatifloxacin was evaluated in patients (n = 33) undergoing vitreous tap during the standard procedure for intravitreal antibiotic injection for acute postoperative endophthalmitis at various time-points. Vitreous penetration of 400 mg oral gatifloxacin was evaluated in the non-inflamed eyes of patients (n = 33) undergoing pars plana vitrectomy at similar time-points. The study was extended to evaluate the vitreous penetration of single-dose oral (800 mg) gatifloxacin at a single time-point in inflamed (n = 10) and non-inflamed (n = 11) eyes. RESULTS After 400 mg oral gatifloxacin, inflamed eyes showed mean vitreous concentrations of 0.58+/-0.19 microg/ml, 1.33+/-0.33 microg/ml and 1.30 +/- 0.23 microg/ml at 2, 4 and 6 hours, respectively. The levels reached at 2 and 4 hours were found to be significantly increased compared with those in non-inflamed eyes. At the 800-mg dose, 4-hour vitreous levels in inflamed and non-inflamed eyes were 1.57 +/- 0.3 microg/ml and 1.42 +/- 0.24 microg/ml, respectively. Although the increased dose of gatifloxacin elevated plasma concentration, it failed to raise vitreous levels significantly higher than the 400-mg dose at the 4-hour time-point. CONCLUSIONS Orally administered gatifloxacin achieves therapeutic levels in both inflamed and non-inflamed human eyes with a spectrum covering the bacterial species most frequently involved in the various causes of endophthalmitis. However, the levels achieved were below the MIC(90) for Pseudomonas aureginosa and Enterococcus.
Collapse
|
32
|
Dahiya S, Chuttani K, Khar RK, Saluja D, Mishra AK, Chopra M. Synthesis and evaluation of Ciprofloxacin derivatives as diagnostic tools for bacterial infection by Staphylococcus aureus. Metallomics 2009; 1:409-17. [PMID: 21305145 DOI: 10.1039/b908474f] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Development of target-specific diagnostic radiopharmaceuticals has always been a challenging task. For this purpose, design and development of the imaging-friendly variant of a potent antibiotic could aid in treatment planning and follow-up of patients with hard-to-diagnose bacterial infections. Fluoroquinolone analogues were synthesized taking the lead from Ciprofloxacin (the broad spectrum antibiotic) molecule. The idea of modifying fluoroquinolones, and subsequently labeling them, was to preserve their capacity to bind bacteria and thereby enable the compound to specifically target those microorganisms. Three compounds were thus synthesized as derivatives of Ciprofloxacin. The fluoroquinolone analogues were labeled with (99m)Tc by using (99m)Tc pertechnetate with high labeling efficiency for all the formulations. The complexes formed by chelation of (99m)Tc with our synthesized fluoroquinolone analogues showed good in vitro serum stability. The blood clearance study performed in New Zealand White rabbits exhibited a curve indicating the initial fast phase in which radiocomplexed drugs cleared from blood very quickly followed by a slow phase. The in vivo evaluation showed that fluoroquinolone-based radiopharmaceuticals bind to the bacteria present at the site of infection, which results in the retention of the agent at sites of active bacterial infection. The biodistribution data and the scintigrams demonstrated that Staphylococcus aureus bacteria in animal infection models took up the radiopharmaceutical formulations, confirming our hypothesis that (99m)Tc fluoroquinolone derivatives might be useful as diagnostic agents for targeted delivery in bacterial infections.
Collapse
Affiliation(s)
- Saurabh Dahiya
- Dr B. R. Ambedkar Center for Biomedical Research, University of Delhi, Delhi-110007, India
| | | | | | | | | | | |
Collapse
|
33
|
Koba M, Bączek T, Macur K, Bober L, Frąckowiak T, Buciński A, Rystok-Grabska D, Stasiak J, Koba K. Factor analysis of microbiological activity data and structural parameters of antibacterial quinolones. J Mol Model 2009; 16:327-35. [DOI: 10.1007/s00894-009-0549-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2009] [Accepted: 06/11/2009] [Indexed: 10/20/2022]
|
34
|
Moura A, Nicolau A, Hooton T, Azeredo J. Antibiotherapy and pathogenesis of uncomplicated UTI: difficult relationships. J Appl Microbiol 2009; 106:1779-91. [PMID: 19210569 DOI: 10.1111/j.1365-2672.2008.04115.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
In a time when conventional antibiotics are becoming increasingly less effective for treatment of infections, the relationship between bacteria and antimicrobial resistance is becoming more and more complicated. This paper provides a current review of studies reported in the literature pertaining to the antibiotherapy of human urinary tract infections (UTI), in a way that helps the reader direct a bibliographic search and develop an integrated perspective of the subject. Highlights are given to (bio)pathogenesis of uncomplicated cystitis. Features associated with the antibiotherapy of UTI such as development of resistance are presented in the text systematically. This review discusses recent advances in the understanding of how the predominant uropathogen Escherichia coli interacts with its host and leads to infection; so one can understand some of the reasons behind antibiotherapy failures.
Collapse
Affiliation(s)
- A Moura
- IBB - Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar, P-4710-057 Braga, Portugal
| | | | | | | |
Collapse
|
35
|
Prevalence and risk factors for selection of quinolone-resistant Escherichia coli strains in fecal flora of patients receiving quinolone therapy. Antimicrob Agents Chemother 2008; 53:1287-9. [PMID: 19064895 DOI: 10.1128/aac.01228-08] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Patients taking quinolones as inpatients (n = 55) or outpatients (n = 40) and newly hospitalized patients who were not on quinolone therapy (n = 41) were assessed for fecal carriage of quinolone-resistant Escherichia coli (QREC) strains before and after therapy/hospitalization. Fluoroquinolone use in the previous 6 months was found to be a risk factor for QREC carriage before therapy/hospitalization. The prevalence of QREC strains in fecal flora increased steadily with the duration of quinolone therapy.
Collapse
|
36
|
Das BB, Ganguly A, Majumder HK. DNA Topoisomerases of Leishmania: The Potential Targets for Anti-Leishmanial Therapy. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008; 625:103-15. [DOI: 10.1007/978-0-387-77570-8_9] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
|
37
|
Mitsuyama J. [Basis of quinolone antibiotics]. Nihon Yakurigaku Zasshi 2007; 130:287-293. [PMID: 17938514 DOI: 10.1254/fpj.130.287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
|
38
|
Karbiwnyk CM, Carr LE, Turnipseed SB, Andersen WC, Miller KE. Determination of quinolone residues in shrimp using liquid chromatography with fluorescence detection and residue confirmation by mass spectrometry. Anal Chim Acta 2007; 596:257-63. [PMID: 17631104 DOI: 10.1016/j.aca.2007.06.018] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2007] [Revised: 06/06/2007] [Accepted: 06/10/2007] [Indexed: 12/01/2022]
Abstract
The quinolones, oxolinic acid (OXO), flumequine (FLU), and nalidixic acid (NAL), are antibacterial drugs effective against gram-negative bacteria. Quinolones are used in both human and veterinary medicine, but are currently not approved by the U.S. Food and Drug Administration for use in food fish. A liquid chromatography-fluorescence (LC-FL) method was developed to determine OXO, FLU, and NAL residues in shrimp. An additional liquid chromatography-mass spectrometry (LC-MS(n)) method was created to confirm these residues using the same sample extract. Samples were prepared with a simple ethyl acetate extraction followed by solvent exchange into 0.2% formic acid and cleaned-up with hexane. Reverse phase chromatography was used to separate the three compounds in both procedures. For the LC-FL determinative method, fluorescence emission was monitored at 369 nm with excitation at 327 nm. With electrospray ionization, the three most abundant ions from the MS3 product ion spectrum were used to identify OXO, FLU, and NAL in the confirmation procedure. Shrimp samples fortified at levels ranging from 7.5 to 100 ng g(-1) were used to validate both methods.
Collapse
Affiliation(s)
- Christine M Karbiwnyk
- Animal Drugs Research Center, Food and Drug Administration, Denver, CO, United States.
| | | | | | | | | |
Collapse
|
39
|
Wang Z, Grasela DM, Krishna G. Retrospective analysis of electrocardiographic changes after administration of oral or intravenous garenoxacin in five phase I, placebo-controlled studies in healthy volunteers. Clin Ther 2007; 29:1098-106. [PMID: 17692724 DOI: 10.1016/j.clinthera.2007.06.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/24/2007] [Indexed: 11/24/2022]
Abstract
BACKGROUND Certain fluoroquinolones and macrolide antibiotics have been associated with prolongation of the corrected QT (QTc) interval or QT dispersion, leading to cardiac arrhythmias. Garenoxacin is a des-F(6)-quinolone with broad-spectrum antimicrobial activity and a favorable pharmacokinetic/pharmacodynamic profile. Its effects on electrocardiographic (ECG) parameters in healthy volunteers have not been reported. OBJECTIVE The cardiac safety profile of garenoxacin was further examined using data from healthy volunteers enrolled in 5 dose-ranging and comparative Phase I clinical studies. METHODS This was a retrospective analysis of 5 randomized, double-blind, placebo-controlled studies in which 224 healthy volunteers received oral or intravenous garenoxacin (50-1200 mg/d) for 1 to 28 days' dosing duration (<or=14 days' therapeutic duration). The effects of garenoxacin on the QT interval corrected using Bazett's formula (QTcB) and Fridericia's formula (QTcF) and the PR interval were assessed by counts of outliers, linear regressions, and exposure-response plots. Absence of a concentration-dependent effect of garenoxacin on changes from baseline ECG parameters was concluded if the 95% CI for the linear regression slopes of derived QTc- or PR-interval parameters relative to Cmax and C(avg0-12) (average garenoxacin plasma concentration from 0-12 hours after dosing) values for garenoxacin contained zero. RESULTS No clinically relevant changes in the QTc or PR intervals were observed over a range of garenoxacin plasma concentrations (Cmax: 0.5-38.6 microg/mL, oral dose range; 3.36-21.4 microg/mL, intravenous dose range). No volunteer had a prolongation from baseline that exceeded established thresholds for the QTcB or QTcF interval (>450 milliseconds for men, >470 milliseconds for women) or the PR interval (>250 milliseconds). One subject had a change in QTcB of 67 milliseconds 4 hours after administration of garenoxacin 400 mg PO on day 7, but the actual value was 418 milliseconds (baseline, 351 milliseconds); the corresponding change in QTcF was 49 milliseconds (actual, 408 milliseconds; baseline, 359 milliseconds). The means for other derived ECG parameters were generally similar between garenoxacin-treated volunteers and placebo controls. CONCLUSION In this retrospective analysis of data from healthy volunteers, garenoxacin had no clinically relevant dose-, route-of-administration-, or concentration-dependent effects on the QTc or PR interval across a dose range from 50 to 1200 mg/d.
Collapse
Affiliation(s)
- Zaiqi Wang
- Schering-Plough Research Institute, Kenilworth, New Jersey 07033, USA.
| | | | | |
Collapse
|
40
|
Abstract
This review discusses the current therapy for bacterial keratitis, especially that using quinolones of the fourth generation. In addition, the importance of additive steroids is discussed. Steroids should be administered at a low dose and tapered off slowly, whereas antibiotics should be applied at a high dosage and discontinued abruptly.
Collapse
Affiliation(s)
- W Behrens-Baumann
- Augenklinik der Otto-von-Guericke-Universität, 39120, Leibziger Strasse 44, Magdeburg, Germany.
| | | |
Collapse
|
41
|
Vila J, Sánchez-Céspedes J, Sierra JM, Piqueras M, Nicolás E, Freixas J, Giralt E. Antibacterial evaluation of a collection of norfloxacin and ciprofloxacin derivatives against multiresistant bacteria. Int J Antimicrob Agents 2006; 28:19-24. [PMID: 16781123 DOI: 10.1016/j.ijantimicag.2006.02.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2005] [Accepted: 02/03/2006] [Indexed: 11/19/2022]
Abstract
The objective of this study was to analyse an array of ciprofloxacin and norfloxacin derivatives in order to determine those with good activity against bacteria that already present fluoroquinolone resistance associated with mutations in the gyrA and/or parC genes. Four norfloxacin and 20 ciprofloxacin derivatives were synthesised and tested against quinolone-susceptible and -resistant Escherichia coli, Acinetobacter baumannii, Stenotrophomonas maltophilia and Staphylococcus aureus strains using a microdilution test. Among the derivatives, the 4-methyl-7-piperazine ciprofloxacin derivative showed a minimum inhibitory concentration for 50% of the organisms that was 16- and 8-fold lower than ciprofloxacin for A. baumannii and S. maltophilia, respectively. When the methyl group at position 4 in the piperazine ring was substituted by ethyl, butyl or heptyl groups, activity against A. baumannii steadily decreased. The 7-(4-methyl)-piperazine ciprofloxacin derivative (UB-8902) showed very good activity against these multiresistant microorganisms including A. baumannii and S. maltophilia.
Collapse
Affiliation(s)
- J Vila
- Servei de Microbiologia, Centre de Diagnòstic Biomèdic, Hospital Clinic, Villarroel 170, 08036 Barcelona, Spain.
| | | | | | | | | | | | | |
Collapse
|
42
|
Foroumadi A, Oboudiat M, Emami S, Karimollah A, Saghaee L, Moshafi MH, Shafiee A. Synthesis and antibacterial activity of N-[2-[5-(methylthio)thiophen-2-yl]-2-oxoethyl] and N-[2-[5-(methylthio)thiophen-2-yl]-2-(oxyimino)ethyl]piperazinylquinolone derivatives. Bioorg Med Chem 2006; 14:3421-7. [PMID: 16427290 DOI: 10.1016/j.bmc.2005.12.058] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2005] [Revised: 12/29/2005] [Accepted: 12/29/2005] [Indexed: 10/25/2022]
Abstract
A number of N-substituted piperazinylquinolone derivatives were synthesized and evaluated for antibacterial activity against Gram-positive and Gram-negative bacteria. Preliminary results indicated that most compounds tested in this study demonstrated comparable or better activity against Staphylococcus aureus and Staphylococcus epidermidis than their parent piperazinylquinolones as reference drugs. Among these derivatives, ciprofloxacin derivative 5a, containing N-[2-[5-(methylthio)thiophen-2-yl]-2-oxoethyl] residue, showed significant improvement of potency against staphylococci, maintaining Gram-negative coverage.
Collapse
Affiliation(s)
- Alireza Foroumadi
- Faculty of Pharmacy and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, Tehran 14174, Iran
| | | | | | | | | | | | | |
Collapse
|
43
|
Conrads G, Citron DM, Goldstein EJC. Genetic determinant of intrinsic quinolone resistance in Fusobacterium canifelinum. Antimicrob Agents Chemother 2005; 49:434-7. [PMID: 15616329 PMCID: PMC538909 DOI: 10.1128/aac.49.1.434-437.2005] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Fourteen fluoroquinolone-resistant fusobacterial strains, originating from cats or dogs, were characterized by sequencing of the 16S-23S and 16S rRNA genes and DNA-DNA hybridization and were described as a new species, Fusobacterium canifelinum. All of the strains are intrinsically resistant (MIC, >4 g/ml) to levofloxacin and other fluoroquinolones. Compared to the quinolone resistance-determining region (gyrA) of the susceptible relative F. nucleatum, we found that Ser79 was replaced with leucine and Gly83 was replaced with arginine.
Collapse
Affiliation(s)
- Georg Conrads
- Division of Oral Microbiology and Immunology University Hospital, Pauwelsstrasse 30, D-52057 Aachen, Germany.
| | | | | |
Collapse
|
44
|
Abstract
Moxifloxacin (Avelox) is a fluoroquinolone antibacterial with a methoxy group in the C-8 position and a bulky C-7 side chain. Moxifloxacin is approved for use in the treatment of acute exacerbations of chronic bronchitis (AECB), community-acquired pneumonia (CAP), acute bacterial sinusitis and uncomplicated skin and skin structure infections (approved indications may differ between countries). Moxifloxacin has a broad spectrum of antibacterial activity, including activity against penicillin-resistant Streptococcus pneumoniae. It achieves good tissue penetration and has a convenient once-daily administration schedule, as well as being available in both intravenous and oral formulations in some markets. Moxifloxacin has good efficacy in the treatment of patients with AECB, CAP, acute bacterial sinusitis and uncomplicated skin and skin structure infections, and is generally well tolerated. Thus, moxifloxacin is an important option in the treatment of bacterial infections.
Collapse
|
45
|
Renuka K, Kapil A, Kabra SK, Wig N, Das BK, Prasad VVSP, Chaudhry R, Seth P. Reduced susceptibility to ciprofloxacin and gyra gene mutation in North Indian strains of Salmonella enterica serotype Typhi and serotype Paratyphi A. Microb Drug Resist 2004; 10:146-53. [PMID: 15256030 DOI: 10.1089/1076629041310028] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The emergence of reduced susceptibility to ciprofloxacin among Salmonella enterica serotype Typhi and serotype Paratyphi A leading to clinical failure of treatment poses a great therapeutic challenge. The mechanism of fluoroquinolone resistance in clinical isolates of S. Typhi and S. Paratyphi A is not very well documented. The present study was carried out with the objective of molecular characterization of reduced quinolone susceptibility amongst the strains of S. Typhi and S. Paratyphi A isolated from the patients with enteric fever during January, 2000, to April, 2003, in a North Indian hospital. A total of 422 culture-positive cases of enteric fever were reported to the hospital during the period of study, of which S. Typhi was isolated from 350 cases and S. Paratyphi A from 72 cases. The antimicrobial susceptibility of these strains was determined by disk diffusion and agar dilution method according to NCCLS guidelines, and E-test method. A total of 140 randomly selected strains, isolated during the years 1993-1999, that were available from the laboratory stocks were also studied to compare with the present strains. To study the quinolone susceptibility, the strains were divided into nalidixic acid sensitive (NAS), nalidixic acid intermediate resistant, (NAI) and nalidixic acid resistant (NAR) on the basis of susceptibility to nalidixic acid. Clinical history was available from 174 patients, of which 93 needed hospitalization due to severe disease. Of these, 82 patients were infected with NAR strains and 22 patients had a documented evidence of clinical failure to ciprofloxacin therapy. The patients infected with NAR strains were younger and had a significantly longer duration of fever (p value < 0.05) than those infected with NAS strains. It was observed that the proportion of NAR strains increased gradually over the years. These strains had a significantly higher range of MIC of ciprofloxacin (0.023-1.0 microg/ml) as compared to the NAS strains (0.002-0.125 microg/ml) (p value < 0.05). The sequencing of quinolone resistance determining region (QRDR) of the gyrA gene showed the presence of mutation at either Ser 83 or at Asp 87 in all the NAR and NAI strains. None of the NAS strains had a mutation, suggesting that the gyrA gene mutation is sufficient to confer resistance to nalidixic acid and reduced susceptibility to ciprofloxacin. This mutation, although phenotypically expressed as decreased susceptibility to ciprofloxacin, goes undetected by the disk diffusion method using the present NCCLS guidelines. Hence, it can increase morbidity and mortality due to delay in appropriate antibiotic treatment.
Collapse
Affiliation(s)
- K Renuka
- Department of Microbiology, India Institute of Medical Sciences, New Delhi, India
| | | | | | | | | | | | | | | |
Collapse
|
46
|
Rigos G, Nengas I, Alexis M, Troisi GM. Potential drug (oxytetracycline and oxolinic acid) pollution from Mediterranean sparid fish farms. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2004; 69:281-288. [PMID: 15276333 DOI: 10.1016/j.aquatox.2004.05.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2004] [Revised: 05/18/2004] [Accepted: 05/25/2004] [Indexed: 05/24/2023]
Abstract
The potential for input of two common antibacterial agents in Mediterranean fish farms, oxytetracycline (OTC) and oxolinic acid (OA), was estimated from measurements of these drugs in the faecal excretions of two important farmed sparids, gilthead sea bream, Sparus aurata and sharpsnout sea bream Diplodus puntazzo. Oxolinic acid was found to be well absorbed by gilthead sea bream (92%) and sharpsnout sea bream (88%) while the absorption of OTC was found to be considerably lower in both species (27 and 40%, respectively). These data were integrated with production records for sparids, drug dosage regimes and treatment frequency information to calculate potential annual drug release to the aquatic environment from Greek fish farms. These calculations suggest potentially significant quantities of unmetabolised OTC can be passed unabsorbed through the body of treated sparids and excreted via the faeces into the local marine environment. The situation with OA was much less pronounced. It was estimated that potentially more than 1900 kg of OTC and more than 50 kg of OA may be released via faecal excretion into the environment by sparid farms per year. Further drug may also be released via uneaten medicated feed, leached drugs and other routes of fish elimination (renal excretion, branchial secretions). Drug pollution of the marine environment in the vicinity of fish farms can have adverse ecological effects, including development of resistant bacterial populations and exposure with potential drug accumulation in aquatic fauna and flora.
Collapse
Affiliation(s)
- George Rigos
- Laboratory of Fish Nutrition and Pathology, National Centre for Marine Research, Aghios Kosmas 16610, Ellinikon, Attiki, Greece.
| | | | | | | |
Collapse
|
47
|
Das A, Dasgupta A, Sengupta T, Majumder HK. Topoisomerases of kinetoplastid parasites as potential chemotherapeutic targets. Trends Parasitol 2004; 20:381-7. [PMID: 15246322 DOI: 10.1016/j.pt.2004.06.005] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The protozoan parasites Trypanosoma, Leishmania and Crithidia, which belong to the order kinetoplastidae, emerge from the most ancient eukaryotic lineages. The diversity found in the life cycle of these organisms must be directed by genetic events, wherein topoisomerases play an important role in cellular processes affecting the topology and organization of intracellular DNA. Topoisomerases are valuable as potential drug targets because they have indispensable function in cell biology. This review summarizes what is known about topoisomerase genes and proteins of kinetoplastid parasites and the roles of these enzymes as targets for therapeutic agents.
Collapse
Affiliation(s)
- Aditi Das
- Sealy Center for Molecular Sciences, University of Texas Medical Branch at Galveston, Galveston, TX 77555, USA
| | | | | | | |
Collapse
|
48
|
Abstract
DNA topoisomerases are a class of enzymes that alter the topology of DNA and are targets of several anticancer drugs. Camptothecins (CPTs) are a relatively new family of compounds that specifically target topoisomerase I (Top1). These compounds "poison" Top1 by binding to the Top1-DNA complex in a manner that prevents the religation of DNA. Topotecan and irinotecan are two CPTs that are approved for the treatment of a variety of malignancies, including colorectal, ovarian, and small cell lung cancers, as well as myeloid malignancies. Although CPTs have proven to be effective anticancer drugs, resistance is still a critical clinical problem. The mechanisms underlying de novo and acquired clinical resistance to CPTs and the newer classes of Top1 poisons are unclear. However, based on preclinical studies, it is likely that clinical resistance to these drugs is the result of: (1) inadequate accumulation of drug in the tumor, (2) resistance-conferring alterations in Top1, or (3) alterations in the cellular response to the Top1-CPT interaction. This review will focus on the current knowledge regarding mechanisms of resistance to CPTs and other Top1-targeting drugs.
Collapse
Affiliation(s)
- Zeshaan A Rasheed
- The Cancer Institute of New Jersey, Department of Molecular and Cellular Pharmacology, UMDNJ-Robert Wood Johnson Medical School, 195 Little Albany Street, New Brunswick, NJ 08901, USA.
| | | |
Collapse
|
49
|
Abstract
BACKGROUND Respiratory tract infections among children are a common reason for health care provider visits and the primary reason for antimicrobial prescribing in this population. The increased prevalence of resistance among Streptococcus pneumoniae and Haemophilus influenzae pathogens poses a serious challenge in the successful treatment of respiratory tract infections caused by these pathogens. METHODS This paper reviews worldwide trends in antimicrobial resistance among common respiratory tract pathogens, highlighting data obtained from the pediatric population where available. RESULTS S. pneumoniae resistance to beta-lactams is mediated through alterations in the penicillin-binding proteins and macrolide resistance to acquisition of efflux or methylation genes. The mechanisms of resistance to the fluoroquinolones include target enzyme alterations via genetic mutations and transport out of the bacterial cell via an efflux pump. Beta-lactamase production is the primary mechanism of resistance to penicillins among H. influenzae isolates. Although S. pneumoniae with reduced susceptibility to penicillin was first documented > 30 years ago, resistance has increased at an alarming rate worldwide in the past decade. According to recent surveillance data, the worldwide prevalence of S. pneumoniae with reduced susceptibility to penicillin is 18.2%. Beta-lactamase production among H. influenzae ranges from approximately 4% in Russia to 26% in the United States and to 31% in France. The prevalence of beta-lactamase-negative, ampicillin-resistant H. influenzae remains very low (< 1%) worldwide, except in Japan, where the incidence is higher. In general, the highest rates of resistance are observed in isolates obtained from children, and risk factors for infection with a resistant pathogen include young age, the site of infection, day-care center attendance and recent antimicrobial use. CONCLUSIONS Increased prevalence of antimicrobial resistance among respiratory tract pathogens isolated from children and adults is evident worldwide. Treatment of infections caused by S. pneumoniae and H. influenzae with older agents or ineffective dosing regimens may not eradicate infections and may contribute to the spread of resistance. These observations confirm the need for appropriate antimicrobial use to halt or at least limit the spread of resistance.
Collapse
Affiliation(s)
- Michael R Jacobs
- Case Western Reserve University and University Hospitals of Cleveland, Cleveland, OH, USA
| |
Collapse
|
50
|
Abstract
The availability of genome sequences is revolutionizing the field of microbiology. Genetic methods are being modified to facilitate rapid analysis at a genome-wide level and are blossoming for human pathogens that were previously considered intractable. This revolution coincided with a growing concern about the emergence of microbial drug resistance, compelling the pharmaceutical industry to search for new antimicrobial agents. The availability of the new technologies, combined with many genetic strategies, has changed the way that researchers approach antibacterial drug discovery.
Collapse
Affiliation(s)
- Lynn Miesel
- Department of Antimicrobial Therapy, Schering-Plough Research Institute, 2015 Galloping Hill Road, Kenilworth, New Jersey 07033-0530, USA.
| | | | | |
Collapse
|