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Ramdhani D, Kusuma SAF, Sediana D, Bima APH, Khumairoh I. Comparative study of cefixime and tetracycline as an evaluation policy driven by the antibiotic resistance crisis in Indonesia. Sci Rep 2021; 11:18461. [PMID: 34531515 PMCID: PMC8445965 DOI: 10.1038/s41598-021-98129-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 08/31/2021] [Indexed: 01/08/2023] Open
Abstract
Antibiotic resistance is a serious threat that occurs globally in the health sector due to increased consumption of inappropriate antibiotics. Guidelines for prescribing antibiotics for ARTIs have been issued in general practice to promote rational antibiotic prescribing. This study was conducted to compare the effectiveness of cefixime and tetracycline as a solution to improve monitoring of appropriate antibiotic use in the treatment of ARTIs. All stock isolates were rejuvenated first, and cultured on standard media and Kirby-Bauer disc diffusion method was used for susceptibility testing in accordance with the Clinical and Laboratory Standard Institute's (CLSI) recommendations. Identification of bacteria from a single isolate was carried out to determine which bacteria were resistant to cefixime and tetracycline. A total of 466 single isolates of bacteria were analyzed, which showed a percentage of resistance to cefixime 38.0%, and tetracycline 92.86%. Bacterial isolates were resistant to cefixime and tetracycilne was a genus of Haemophilus, Streptococcus, Corynebacterium, Staphylococcus, and bordetella. Cefixime compared to tetracycline was proven to be superior in terms of the effectiveness of ARIs treatment.
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Affiliation(s)
- Danni Ramdhani
- Department of Pharmaceutical Analysis and Medicinal Chemistry, Faculty of Pharmacy, Padjadjaran University, Sumedang, Indonesia.
| | - Sri Agung Fitri Kusuma
- Department of Biology Pharmacy, Faculty of Pharmacy, Padjadjaran University, Sumedang, Indonesia
| | - Dede Sediana
- Pharmaceutical Division, Tasikmalaya City Health Office, Tasikmalaya, West Java Province, Indonesia
| | - A P Hilarius Bima
- Department of Biology Pharmacy, Faculty of Pharmacy, Padjadjaran University, Sumedang, Indonesia
| | - Ika Khumairoh
- Department of Biology Pharmacy, Faculty of Pharmacy, Padjadjaran University, Sumedang, Indonesia
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2
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Greenwood D. What's the Use of Susceptibility Testing? J Chemother 2021. [DOI: 10.1080/1120009x.1997.12113184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- D. Greenwood
- Division of Microbiology & Infectious Diseases, Department of Clinical Laboratory Sciences, University Hospital, Queen's Medical Centre, Nottingham NG7 2UH, UK. Fax.
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3
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Takano C, Kuramochi Y, Seki M, Kim DW, Omagari D, Sasano M, Chang B, Ohnishi M, Kim EJ, Fuwa K, Kilgore PE, Hoshino T, Hayakawa S. Molecular serotype-specific identification of Streptococcus pneumoniae using loop-mediated isothermal amplification. Sci Rep 2019; 9:19823. [PMID: 31882619 PMCID: PMC6934563 DOI: 10.1038/s41598-019-56225-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 12/09/2019] [Indexed: 11/14/2022] Open
Abstract
In children, the incidence of pneumococcal meningitis has decreased since the introduction of pneumococcal conjugate vaccine (PCV7 and PCV13). However, since the introduction of the vaccine, developed countries have seen the emergence of non-PCV13 serotypes. However, invasive pneumococcal disease (IPD) caused by PCV13-targeted serotypes still represents an important public health problem in resource-limited countries. To develop a rapid, simple, and cost-effective assay to detect serotypes of Streptococcus pneumoniae, we developed a novel loop-mediated isothermal amplification (LAMP) assay based on the sequences available for the 13 capsular types that are included in PCV13: 1, 3, 4, 5, 6 A, 6B, 7 F, 9 V, 14, 18 C, 19 A, 19 F, and 23 F. We evaluated test reactivity, specificity, sensitivity and performance, and compared the results between established LAMP and conventional PCR assays. To support its clinical use, the detection limits of the LAMP assay were evaluated using bacterial genomic DNA-spiked cerebrospinal fluid (CSF) and blood specimens. We confirmed the specificity of the LAMP assay using 41 serotypes of pneumococcal strains. The sensitivity of the LAMP assay was 10 to 100 copies per reaction, compared to 10 to 104 copies per reaction for PCR assays. The detection limits of the LAMP assay were comparable when using DNA-spiked CSF and blood specimens, as compared to using purified DNA as the template. In conclusion, a rapid and simple LAMP-based pneumococcal serotyping method has been developed. This is the first report of a LAMP method for a PCV13 serotype-specific identification assay, which could be a promising step to facilitate epidemiological studies of pneumococcal serotyping.
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Affiliation(s)
- Chika Takano
- Division of Microbiology, Department of Pathology and Microbiology, Nihon University School of Medicine, Tokyo, 173-8610, Japan.,Department of Pediatrics and Child Health, Nihon University School of Medicine, Tokyo, 173-8610, Japan
| | - Yoko Kuramochi
- Nihon University School of Medicine, Tokyo, 173-8610, Japan
| | - Mitsuko Seki
- Division of Microbiology, Department of Pathology and Microbiology, Nihon University School of Medicine, Tokyo, 173-8610, Japan. .,Department of Pediatric Dentistry, School of Dentistry, Meikai University, Saitama, Japan.
| | - Dong Wook Kim
- Department of Pharmacy, College of Pharmacy, Hanyang University, Ansan, 15588, Republic of Korea. .,Institute of Pharmacological Research, Hanyang University, Ansan, 15588, Republic of Korea.
| | - Daisuke Omagari
- Nihon University School of Dentistry, Tokyo, 101-8310, Japan
| | - Mari Sasano
- Division of Microbiology, Department of Pathology and Microbiology, Nihon University School of Medicine, Tokyo, 173-8610, Japan.,Department of Neurological Surgery, Nihon University School of Medicine, Tokyo, 173-8610, Japan
| | - Bin Chang
- Bacteriology I, National Institute of Infectious Diseases, Tokyo, 162-8640, Japan
| | - Makoto Ohnishi
- Bacteriology I, National Institute of Infectious Diseases, Tokyo, 162-8640, Japan
| | - Eun Jin Kim
- Department of Pharmacy, College of Pharmacy, Hanyang University, Ansan, 15588, Republic of Korea.,Institute of Pharmacological Research, Hanyang University, Ansan, 15588, Republic of Korea
| | - Kazumasa Fuwa
- Department of Pediatrics and Child Health, Nihon University School of Medicine, Tokyo, 173-8610, Japan
| | - Paul E Kilgore
- Department of Pharmacy Practice, Eugene Applebaum College of Pharmacy & Health Sciences, Wayne State University, Detroit, MI, 48201, USA
| | - Tomonori Hoshino
- Department of Pediatric Dentistry, School of Dentistry, Meikai University, Saitama, Japan
| | - Satoshi Hayakawa
- Division of Microbiology, Department of Pathology and Microbiology, Nihon University School of Medicine, Tokyo, 173-8610, Japan
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4
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Fung HB, Kuczynski S, Finch DA, Ramos L. Current Issues in Gram-Negative Resistance: Extended-Spectrum Beta-Lactamases and Inducible Beta-Lactamases. J Pharm Pract 2016. [DOI: 10.1106/hb54-f01j-r72l-fgmg] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
The production of beta-lactamases is the most common cause of antimicrobial resistance in gram-negative bacilli. Two beta-lactamases, extended-spectrum beta-lactamases (ESBLs) and inducible beta-lactamases (IDBLs), are presently seen with increasing frequency. Treatment of severe infections due to gram-negative bacilli producing these beta-lactamases is problematic. In vitro susceptibility testing of ESBL-producing organisms remains difficult to interpret; clinical isolates sensitive to a particular antimicrobial agent at standard inoculum may become resistant when a higher inoculum is employed. Laboratory detection of IDBL-producing organisms is not yet commercially available. Due to the lack of sufficient outcome data, clinicians often have no choice but to use carbapenems empirically for the treatment of severe infections caused by organisms suspected of producing these enzymes. The widespread empiric use of carbapenems is of concern and may potentially precipitate increased bacterial resistance to this class of antimicrobial agents.
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Affiliation(s)
- Horatio B. Fung
- Critical Care Center, VA Medical Center, 130 West Kingsbridge Road, Bronx, New York 10468
| | - Stephen Kuczynski
- Pharmacy Service, VA Medical Center, 130 West Kingsbridge Road, Bronx, New York 10468
| | - Douglas A. Finch
- Infectious Diseases Section, VA Medical Center, 130 West Kingsbridge Road, Bronx, New York 10468
| | - Liz Ramos
- Department of Pharmaceutical Services, Kingsbrook Jewish Medical Center, 585 Schenectady Avenue, Brooklyn, New York 11203
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5
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Characteristics of Methicillin Resistant Staphylococcus aureus Strains Isolated From Poultry in Iran. ARCHIVES OF CLINICAL INFECTIOUS DISEASES 2015. [DOI: 10.5812/archcid.30885] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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6
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Kim DW, Kilgore PE, Kim EJ, Kim SA, Anh DD, Dong BQ, Kim JS, Seki M. The enhanced pneumococcal LAMP assay: a clinical tool for the diagnosis of meningitis due to Streptococcus pneumoniae. PLoS One 2012; 7:e42954. [PMID: 22900070 PMCID: PMC3416792 DOI: 10.1371/journal.pone.0042954] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2012] [Accepted: 07/16/2012] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Streptococcus pneumoniae is a leading cause of invasive bacterial disease in developed and developing countries. We studied the loop-mediated isothermal amplification (LAMP) technique to assess its suitability for detecting S. pneumoniae nucleic acid in cerebrospinal fluid (CSF). METHODOLOGY/PRINCIPAL FINDINGS We established an improved LAMP assay targeting the lytA gene (Streptococcus pneumoniae [Sp] LAMP). The analytical specificity of the primers was validated by using 32 reference strains (10 Streptococcus and seven non-Streptococcus species) plus 25 clinical alpha-hemolytic streptococcal strains, including four S. pneumoniae strains and 21 other strains (3 S. oralis, 17 S. mitis, and one Streptococcus species) harboring virulence factor-encoding genes (lytA or ply). Within 30 minutes, the assay could detect as few as 10 copies of both purified DNA and spiked CSF specimens with greater sensitivity than conventional polymerase chain reaction (PCR). The linear determination range for this assay is 10 to 1,000,000 microorganisms per reaction mixture using real-time turbidimetry. We evaluated the clinical sensitivity and specificity of the Sp LAMP assay using 106 randomly selected CSF specimens from children with suspected meningitis in Korea, China and Vietnam. For comparison, CSF specimens were also tested against conventional PCR and culture tests. The detection rate of the LAMP method was substantially higher than the rates of PCR and culture tests. In this small sample, relative to the LAMP assay, the clinical sensitivity of PCR and culture tests was 54.5% and 33.3%, respectively, while clinical specificity of the two tests was 100%. CONCLUSIONS/SIGNIFICANCE Compared to PCR, Sp LAMP detected S. pneumoniae with higher analytical and clinical sensitivity. This specific and sensitive LAMP method offers significant advantages for screening patients on a population basis and for diagnosis in clinical settings.
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Affiliation(s)
- Dong Wook Kim
- Department of Pharmacy, College of Pharmacy, Hanyang University, Ansan, Republic of Korea
- Molecular Bacteriology Laboratory, International Vaccine Institute, Seoul, Republic of Korea
| | - Paul E. Kilgore
- Translational Research Division, International Vaccine Institute, Seoul, Republic of Korea
- Wayne State University, Eugene Applebaum College of Pharmacy and Health Sciences, Department of Pharmacy Practice, Detroit, Michigan, United States of America
| | - Eun Jin Kim
- Department of Pharmacy, College of Pharmacy, Hanyang University, Ansan, Republic of Korea
- Molecular Bacteriology Laboratory, International Vaccine Institute, Seoul, Republic of Korea
| | - Soon Ae Kim
- Translational Research Division, International Vaccine Institute, Seoul, Republic of Korea
| | - Dang Duc Anh
- National Institute of Hygiene and Epidemiology, Hanoi, Vietnam
| | - Bai Qing Dong
- Guangxi Zhuang Autonomous Region, Center for Disease Prevention and Control, Nanning, Guangxi, People’s Republic of China
| | - Jung Soo Kim
- Chonbuk National University School of Medicine, Jeonju, Republic of Korea
| | - Mitsuko Seki
- Department of Oral Health Sciences, Nihon University School of Dentistry, Tokyo, Japan
- Dental Research Center, Nihon University School of Dentistry, Tokyo, Japan
- * E-mail:
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7
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Torabi R, Charnova S, Abellar RG, Pinar H, De Paepe ME. Intrauterine infection with Klebsiella pneumoniae: report of a case and literature review. Pediatr Dev Pathol 2008; 11:152-5. [PMID: 17939747 DOI: 10.2350/07-09-0337.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2007] [Accepted: 10/05/2007] [Indexed: 11/20/2022]
Abstract
We report a case of intrauterine Klebsiella pneumoniae infection that resulted in premature rupture of membranes and fetal demise at 20 weeks' gestation in a pregnancy achieved by in vitro fertilization. Postmortem findings included massive panlobar pneumonia, the presence of abundant gram-negative, rod-shaped bacteria within the pulmonary air spaces and the lumen of the gastrointestinal tract, and fetal lung and blood cultures positive for Klebsiella pneumoniae. The placenta showed severe acute chorioamnionitis associated with a brisk fetal inflammatory response (umbilical cord and chorionic plate vasculitis). Marked pancreatic fibrosis was noted, indicative of a preceding necrotizing pancreatitis. In spite of this fulminant histopathologic evidence of intrauterine infection, the infection was clinically silent. This represents, to our knowledge, the 1st reported case of fatal intrauterine Klebsiella pneumoniae infection fully supported by conclusive fetal and placental histopathological evidence.
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Affiliation(s)
- Rozbeh Torabi
- Department of Pathology, Women and Infants Hospital and The Warren Alpert Medical School of Brown University, Providence, RI 02905, USA
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8
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Grossman TH, Bartels DJ, Mullin S, Gross CH, Parsons JD, Liao Y, Grillot AL, Stamos D, Olson ER, Charifson PS, Mani N. Dual targeting of GyrB and ParE by a novel aminobenzimidazole class of antibacterial compounds. Antimicrob Agents Chemother 2007; 51:657-66. [PMID: 17116675 PMCID: PMC1797739 DOI: 10.1128/aac.00596-06] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2006] [Revised: 07/21/2006] [Accepted: 11/07/2006] [Indexed: 11/20/2022] Open
Abstract
A structure-guided drug design approach was used to optimize a novel series of aminobenzimidazoles that inhibit the essential ATPase activities of bacterial DNA gyrase and topoisomerase IV and that show potent activities against a variety of bacterial pathogens. Two such compounds, VRT-125853 and VRT-752586, were characterized for their target specificities and preferences in bacteria. In metabolite incorporation assays, VRT-125853 inhibited both DNA and RNA synthesis but had little effect on protein synthesis. Both compounds inhibited the maintenance of negative supercoils in plasmid DNA in Escherichia coli at the MIC. Sequencing of DNA corresponding to the GyrB and ParE ATP-binding regions in VRT-125853- and VRT-752586-resistant mutants revealed that their primary target in Staphylococcus aureus and Haemophilus influenzae was GyrB, whereas in Streptococcus pneumoniae it was ParE. In Enterococcus faecalis, the primary target of VRT-125853 was ParE, whereas for VRT-752586 it was GyrB. DNA transformation experiments with H. influenzae and S. aureus proved that the mutations observed in gyrB resulted in decreased susceptibilities to both compounds. Novobiocin resistance-conferring mutations in S. aureus, H. influenzae, and S. pneumoniae were found in gyrB, and these mutants showed little or no cross-resistance to VRT-125853 or VRT-752586 and vice versa. Furthermore, gyrB and parE double mutations increased the MICs of VRT-125853 and VRT-752586 significantly, providing evidence of dual targeting. Spontaneous frequencies of resistance to VRT-752586 were below detectable levels (<5.2x10(-10)) for wild-type E. faecalis but were significantly elevated for strains containing single and double target-based mutations, demonstrating that dual targeting confers low levels of resistance emergence and the maintenance of susceptibility in vitro.
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Affiliation(s)
- Trudy H Grossman
- Vertex Pharmaceuticals Incorporated, 130 Waverly Street, Cambridge, MA 02139, USA
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9
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Harakeh S, Yassine H, El-Fadel M. Antimicrobial-resistance of Streptococcus pneumoniae isolated from the Lebanese environment. MARINE ENVIRONMENTAL RESEARCH 2006; 62:181-93. [PMID: 16759688 DOI: 10.1016/j.marenvres.2006.03.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2005] [Revised: 03/17/2006] [Accepted: 03/28/2006] [Indexed: 05/10/2023]
Abstract
The aim of this study was to isolate and molecularly characterize Streptococcus pneumoniae in samples collected from the aquatic environment in Lebanon. For this purpose, 57 samples of ground waters, sea water, sediments and crabs were collected. Biochemical tests as well as PCR were used for further identification and molecular characterization of 46 suspected isolates using specific primers for the lytA-gene and protein 2B-gene. The confirmed isolates were evaluated for their antimicrobial resistance, using the minimum inhibitory concentration method. Crab samples exhibited a high contamination level of an average count of 8.2 x 10(4)CFU/g. In water samples, the highest contamination was recorded near a coastal landfill with a bacterial count of 1.8 x 10(3)CFU/ml whereas the lowest bacterial counts (non detectable) were observed in ground water samples. Twenty out of the 46 suspected isolates came from sea water, and 17 out of those were characterized by PCR as S. pneumoniae. Testing the antimicrobial resistance of the 20 isolates to various antimicrobials showed that all sea water isolates were resistant to vancomycin, gentamicin, and oxacillin (100%), whereas 62.5% were resistant to clindamycin, and only 25% were erythromycin resistant. Resistance rates were higher in the case of fresh water samples, with 57% resistance to erythromycin, and 100% resistance to vancomycin, gentamicin, clindamycin and oxacillin. Alternatively, all tested crab isolates were susceptible to erythromycin. However, they showed a high resistance of 80% against vancomycin, gentamicin, clindamycin and 100% against oxacillin.
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Affiliation(s)
- Steve Harakeh
- Department of Biology, American University of Beirut, P.O. Box 11-0236, Beirut, Lebanon.
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10
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Kunin V, Goldovsky L, Darzentas N, Ouzounis CA. The net of life: reconstructing the microbial phylogenetic network. Genome Res 2005; 15:954-9. [PMID: 15965028 PMCID: PMC1172039 DOI: 10.1101/gr.3666505] [Citation(s) in RCA: 194] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
It has previously been suggested that the phylogeny of microbial species might be better described as a network containing vertical and horizontal gene transfer (HGT) events. Yet, all phylogenetic reconstructions so far have presented microbial trees rather than networks. Here, we present a first attempt to reconstruct such an evolutionary network, which we term the "net of life". We use available tree reconstruction methods to infer vertical inheritance, and use an ancestral state inference algorithm to map HGT events on the tree. We also describe a weighting scheme used to estimate the number of genes exchanged between pairs of organisms. We demonstrate that vertical inheritance constitutes the bulk of gene transfer on the tree of life. We term the bulk of horizontal gene flow between tree nodes as "vines", and demonstrate that multiple but mostly tiny vines interconnect the tree. Our results strongly suggest that the HGT network is a scale-free graph, a finding with important implications for genome evolution. We propose that genes might propagate extremely rapidly across microbial species through the HGT network, using certain organisms as hubs.
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Affiliation(s)
- Victor Kunin
- Computational Genomics Group, The European Bioinformatics Institute, EMBL Cambridge Outstation, Cambridge CB10 1SD, United Kingdom
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11
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Seki M, Yamashita Y, Torigoe H, Tsuda H, Sato S, Maeno M. Loop-mediated isothermal amplification method targeting the lytA gene for detection of Streptococcus pneumoniae. J Clin Microbiol 2005; 43:1581-6. [PMID: 15814969 PMCID: PMC1081357 DOI: 10.1128/jcm.43.4.1581-1586.2005] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
It is difficult to separate Streptococcus pneumoniae from the genotypically similar species Streptococcus mitis and Streptococcus oralis, which are commensals of the human oral cavity. A novel nucleic acid amplification technique, loop-mediated isothermal amplification (LAMP), which amplifies DNA under isothermal conditions (63 degrees C) with high specificity, efficiency, and rapidity, was examined regarding its applicability for detecting S. pneumoniae. An S. pneumoniae-specific LAMP primer targeting the lytA gene was designed. The primer specificity was validated using 10 Streptococcus and 7 non-Streptococcus species. Within 60 min, the assay could detect 10 or more copies of purified S. pneumoniae DNA with a sensitivity 1,000 times that of conventional PCR. Clinical isolates of 21 other strains (3 S. oralis, 17 S. mitis, and 1 Streptococcus species) that harbor virulence-factor-encoding genes (lytA or ply) were tried to differentiate S. pneumoniae. The detection of S. pneumoniae in clinical isolates was more selective using the LAMP method than using conventional PCR. Therefore, LAMP appears to be a sensitive and reliable means of diagnosing S. pneumoniae infection.
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Affiliation(s)
- Mitsuko Seki
- Department of Oral Health Sciences, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan.
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12
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Sahly H, Aucken H, Benedí VJ, Forestier C, Fussing V, Hansen DS, Ofek I, Podschun R, Sirot D, Tomás JM, Sandvang D, Ullmann U. Increased serum resistance in Klebsiella pneumoniae strains producing extended-spectrum beta-lactamases. Antimicrob Agents Chemother 2004; 48:3477-82. [PMID: 15328114 PMCID: PMC514775 DOI: 10.1128/aac.48.9.3477-3482.2004] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The aim of this study was to determine whether there is an association between serum resistance, O serotypes, and the production of extended-spectrum beta-lactamases (ESBLs) in Klebsiella pneumoniae. Ninety ESBL-producing and 178 non-ESBL-producing K. pneumoniae isolates gathered in five European countries were O serotyped and tested for sensitivity to the serum's bactericidal effect. The frequency of serum-resistant isolates was higher among ESBL-producing strains (30%; 27/90 isolates) than among non-ESBL-producing strains (17.9%; 32/178 isolates) (P = 0.037; odds ratio [OR] = 1.96; 95% confidence interval [95% CI] = 1.08 to 3.53). Although O1 was the most common O serotype in both Klebsiella groups, its frequency among ESBL-producing strains was significantly higher (59%; 53/90 isolates) than among non-ESBL producers (36%; 64/178 isolates) (P = 0.0006; OR = 2.5; 95% CI = 1.52 to 4.29). Furthermore, the prevalence of the O1 serotype was higher among serum-resistant strains of both ESBL-producing (74%; 20/27isolates) and non-ESBL producers (75%; 24/32 isolates) than among serum-sensitive ESBL producers (52.4%; 33/63 isolates) and non-ESBL producers (27.4%; 40/146 isolates). Serum resistance among ESBL-producing strains (36%; 17/47 isolates) versus non-ESBL-producing strains (16%; 27/166 isolates) was also significantly higher after the exclusion of clonal strains (P = 0.0056; OR = 2.9; 95% CI = 1.41 to 6.01). Sixteen ESBL types were detected, among which the frequency of serum resistance was significantly lower among the SHV-producing strains (9/48 isolates) than among the TEM producers (16/35 isolates) (P = 0.016; OR = 3.65; CI = 1.3 to 9.7). Curing ESBL-coding plasmids did not influence the serum resistance of the bacteria; all six plasmid-cured derivatives maintained serum resistance. The present findings suggest that ESBL-producing strains have a greater pathogenic potential than non-ESBL-producing strains, but the linkage between O serotypes, serum resistance, and ESBL production remains unclear at this stage.
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Affiliation(s)
- H Sahly
- Department of Medical Microbiology and Virology, University of Kiel, Brunswiker Str. 4, 24105 Kiel, Germany.
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13
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Abstract
Microbiological risk assessments generally focus on estimating adverse human health risks from exposures to human pathogenic microbes. The assessment of potential human health risks posed by pathogens that have acquired resistance to antimicrobial drugs is a new application of risk assessment that is closely related to microbiological risk assessment. Antimicrobial resistance risk assessment is a risk analyticalprocess that focuses on resistance determinants as hazardous agents that might lead to drug-resistant microbial infections in humans exposed to bacteria carrying the determinants. Antimicrobial-resistant infections could occur directly from actively inavading or opportunistic pathogens or indirectly from the transfer of resistance genes to other bacteria. Here, we discuss risk assessment models that might be employed to estimate risks from drug-resistant bacteria in the animal food pathway and the types of models and data that may be used for microbiological risk assessments or antimicrobial resistance risk assessments.
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Affiliation(s)
- H Gregg Claycamp
- US Food and Drug Administration, Center for Veterinary Medicine, Office of New Animal Drug Evaluation, Rockville, Maryland 20855, USA.
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14
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Kurupati P, Chow C, Kumarasinghe G, Poh CL. Rapid detection of Klebsiella pneumoniae from blood culture bottles by real-time PCR. J Clin Microbiol 2004; 42:1337-40. [PMID: 15004113 PMCID: PMC356840 DOI: 10.1128/jcm.42.3.1337-1340.2004] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A LightCycler real-time PCR hybridization probe-based assay which detects a partial Klebsiella pneumoniae 16S rRNA gene was developed for the rapid identification of K. pneumoniae directly from growth-positive blood culture bottles (BACTEC 9240 system) within 2 h. No cross-reactivity was observed with 65 negative-control blood cultures that grew bacteria other than K. pneumoniae and 48 negative blood cultures from double-blind experiments, thus demonstrating 100% specificity when compared to results of conventional biochemical characterization. The assay also showed 100% sensitivity, as it correctly identified all 142 positive-control blood cultures and 4 from double-blind trials.
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Affiliation(s)
- Prathiba Kurupati
- Department of Microbiology, National University of Singapore, Singapore 117597, Republic of Singapore
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15
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Brogden KA, Ackermann M, McCray PB, Tack BF. Antimicrobial peptides in animals and their role in host defences. Int J Antimicrob Agents 2004; 22:465-78. [PMID: 14602364 DOI: 10.1016/s0924-8579(03)00180-8] [Citation(s) in RCA: 303] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Domesticated animals have a large variety of antimicrobial peptides that serve as natural innate barriers limiting microbial infection or, in some instances, act as an integral component in response to inflammation or microbial infection. These peptides differ in size, composition, mechanisms of activity and range of antimicrobial specificities. They are expressed in many tissues, polymorphonuclear leukocytes, macrophages and mucosal epithelial cells. There is a small group of anionic antimicrobial peptides found in ruminants and a much larger group of cationic antimicrobial peptides found in all domesticated animals. The cationic peptides include linear, helical peptides, linear peptides rich in proline and cysteine-stabilized peptides with a beta-sheet and are commonly referred to as cathelicidins and defensins. These peptides are generally broad-spectrum for Gram-positive bacteria, Gram-negative bacteria and fungi (e.g. myeloid antimicrobial peptides, alpha-, beta-defensins, and protegrins) or are specific to one of these groups (e.g. porcine cecropin P1, Bac5, Bac7, PR-39 and prophenin).
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Affiliation(s)
- Kim A Brogden
- Respiratory Diseases of Livestock Research Unit, US Department of Agriculture, Agricultural Research Service, National Animal Disease Center, PO Box 70, Ames, Iowa 50010, USA.
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16
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Abstract
Microorganisms have successfully adapted to changes in food production, processing, and preservation techniques, resulting in a number of new and emerging foodborne pathogens and the re-emergence of organisms that have been problematic in the past. To protect public health, science must meet the challenges that result from the remarkable adaptability of foodborne pathogens. However, not all of the challenges of preventing foodborne illness reside in the realm of science. Food safety policy must evolve in response to new scientific understanding of hazards in the food supply and an ever-changing food processing industry. The laws, regulations, and organizations comprising the food safety system frequently lag behind current scientific knowledge of the risks posed by foodborne pathogens. Future systemic changes to enhance food safety will require better understanding of risks associated with specific pathogens occurring in the food supply and the costs and benefits of implementing mitigation strategies.
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17
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Boojamra CG, Lemoine RC, Blais J, Vernier NG, Stein KA, Magon A, Chamberland S, Hecker SJ, Lee VJ. Synthetic dihydropacidamycin antibiotics: a modified spectrum of activity for the pacidamycin class. Bioorg Med Chem Lett 2003; 13:3305-9. [PMID: 12951115 DOI: 10.1016/s0960-894x(03)00682-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Dihydropacidamycins having an antibacterial spectrum modified from that of the natural product pacidamycins and mureidomycins have been synthesized. Synthetic dihydropacidamycins with noteworthy antibacterial activity against wild-type and resistant Escherichia coli have been identified (MIC=4-8 microg/mL). Some dihydropacidamycins are shown to have activity against multi-resistant clinical strains of Mycobacterium tuberculosis. Compounds of this class are inhibitors of the cell wall biosynthetic enzyme, MraY.
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Affiliation(s)
- Constantine G Boojamra
- Essential Therapeutics, Inc. (formerly Microcide Pharmaceuticals, Inc.), 850 Maude Avenue, Mountain View, CA 94043, USA.
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18
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Oliva B, Miller K, Caggiano N, O'Neill AJ, Cuny GD, Hoemann MZ, Hauske JR, Chopra I. Biological properties of novel antistaphylococcal quinoline-indole agents. Antimicrob Agents Chemother 2003; 47:458-66. [PMID: 12543644 PMCID: PMC151732 DOI: 10.1128/aac.47.2.458-466.2003] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The antibacterial properties of novel quinoline-indole (QI) agents were examined. QI agents demonstrated potent bactericidal activities against Staphylococcus aureus, killing by lytic and nonlytic mechanisms. S. aureus mutants resistant to a lytic QI agent (SEP 155342) and a nonlytic QI agent (SEP 118843) arose at frequencies of 1.4 x 10(-9) and 1.2 x 10(-8), respectively, by selection at four times the MICs. Mutants resistant to QI agent SEP 155342 were unstable, but mutants resistant to QI agent SEP 118843 displayed stable resistance. Mutants resistant to QI agent SEP 118843 were not cross resistant to other inhibitors, including QI agent SEP 155342. Addition of QI agents SEP 118843 and SEP 155342 at four times the MIC caused nonspecific inhibition of several macromolecular biosynthetic pathways in S. aureus. Within 10 min, QI agents SEP 118843 and SEP 155342 both interfered with bacterial membrane integrity, as measured by uptake of propidium iodide. Agents from the two classes of the QI agents probably kill staphylococci by separate mechanisms which, nevertheless, both involve interference with cytoplasmic membrane function. Precise structure-activity relationships for the division of QI agents into two classes could not be determined. However, lytic activity was often associated with substitution of a basic amine at position 4 of the quinoline nucleus, whereas compounds with nonlytic activity usually contained an aromatic ring with or without a methoxy substituent at position 4. Nonlytic QI agents such as SEP 118843 may possess selective activity against the prokaryotic membrane since this compound failed to lyse mouse erythrocytes when it was added at a concentration equivalent to four times the MIC for S. aureus.
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Affiliation(s)
- Brunello Oliva
- Department of Experimental Medicine, University of L'Aquila, Coppito-67100, L'Aquila, Italy
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19
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Abstract
Bronchitis, bronchiectasis, and pneumonia are the most common respiratory tract infections observed in older people and are the leading causes of morbidity and mortality associated with infection. Accurate diagnosis of respiratory tract infections in older people is problematic because of the lack of clear symptoms and signs that are usually seen in younger patients. In addition, the increasing prevalence of bacterial resistance to antibiotic therapy highlights the importance of appropriate therapy. The following review examines the issues associated with the accurate diagnosis of respiratory tract infections, optimal therapy for older patients, and the mechanisms of emerging bacterial resistance to antibiotic therapy.
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Affiliation(s)
- Robert A Bonomo
- Louis Stokes Veterans Affairs Medical Center, Geriatric CARE Center, University Hospitals of Cleveland, Cleveland, Ohio, USA.
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20
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Abstract
We describe in this paper the synthesis of 1,2-di-O-acetyl-5-azido-3,5-dideoxy-alpha,beta-L-arabinofuranose, a carbohydrate donor that was used for the synthesis of 1-(5'-amino-3',5'-dideoxy-alpha-L-arabinofuranosyl)uracil, the nucleoside found in dihydropacidamycin D. The carbohydrate donor was also used for the synthesis of a set of new nucleosides that were introduced in new dihydropacidamycins. These compounds were tested for biological activity, and the results showed that uracil is the only base recognized by MraY.
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Affiliation(s)
- Rémy C Lemoine
- Essential Therapeutics, Inc., 850Maude Avenue, Mountain View, CA 94043, USA.
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21
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Jonas BM, Murray BE, Weinstock GM. Characterization of emeA, a NorA homolog and multidrug resistance efflux pump, in Enterococcus faecalis. Antimicrob Agents Chemother 2001; 45:3574-9. [PMID: 11709342 PMCID: PMC90871 DOI: 10.1128/aac.45.12.3574-3579.2001] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We hypothesized that multidrug resistance efflux pumps (MDRs) may be contributing to the drug resistance of enterococci. We recently identified potential MDR-encoding genes in the Enterococcus faecalis V583 genome. Among the putative MDRs, we found a gene that encodes a NorA homolog and have characterized this enterococcal MDR in the present study. A mutant from which the enterococcal NorA homolog has been deleted has reduced resistance to several NorA substrates. Complementation of the deletion mutant with the wild-type gene verified the involvement of this enterococcal gene in resistance to ethidium bromide (EtBr) and norfloxacin. Known MDR inhibitors (reserpine, lansoprazole, and verapamil) inhibit the efflux of EtBr and norfloxacin in wild-type strain OG1RF. A fluorescence assay with EtBr allowed us to quantitate the efflux capability of the enterococcal NorA pump. On the basis of these results, we have named this enterococcal gene emeA (enterococcal multidrug resistance efflux).
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Affiliation(s)
- B M Jonas
- Department of Microbiology and Molecular Genetics, University of Texas Medical School, Houston, Texas 77030, USA
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22
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McAvin JC, Reilly PA, Roudabush RM, Barnes WJ, Salmen A, Jackson GW, Beninga KK, Astorga A, McCleskey FK, Huff WB, Niemeyer D, Lohman KL. Sensitive and specific method for rapid identification of Streptococcus pneumoniae using real-time fluorescence PCR. J Clin Microbiol 2001; 39:3446-51. [PMID: 11574554 PMCID: PMC88370 DOI: 10.1128/jcm.39.10.3446-3451.2001] [Citation(s) in RCA: 125] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Molecular surveillance of pathogens has shown the need for rapid and dependable methods for the identification of organisms of clinical and epidemiological importance. As the leading cause of community-acquired pneumonia, Streptococcus pneumoniae was used as a model organism to develop and refine a real-time fluorescence PCR assay and enhanced DNA purification method. Seventy clinical isolates of S. pneumoniae, verified by latex agglutination, were screened against 26 negative control clinical isolates employing a TaqMan assay on a thermocycler (LightCycler). The probe, constructed from the lytA gene, correctly detected all S. pneumoniae genomes without cross-reaction to negative controls. The speed and ease of this approach will make it adaptable to identification of many bacterial pathogens and provide potential for adaptation to direct detection from patient specimens.
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Affiliation(s)
- J C McAvin
- Molecular Epidemiology Branch, Air Force Institute for Environment and Occupational Health Risk Analysis/Epidemiology Surveillance Division, Brooks Air Force Base, San Antonio, Texas 78235, USA
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23
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Svec P, Sedlácek I, Pantůcek R, Devriese LA, Doskar JV. Evaluation of ribotyping for characterization and identification of Enterococcus haemoperoxidus and Enterococcus moraviensis strains. FEMS Microbiol Lett 2001; 203:23-7. [PMID: 11557135 DOI: 10.1111/j.1574-6968.2001.tb10815.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Seven Enterococcus moraviensis and 16 Enterococcus haemoperoxidus as well as nine reference cultures of other enterococcal species obtained from the Czech Collection of Microorganisms were characterized using ribotyping with EcoRI and HindIII in the present work. The ribopatterns obtained by both restriction enzymes clearly distinguished all E. moraviensis and E. haemoperoxidus strains from the other enterococci (E. faecalis, E. faecium, E. avium, E. raffinosus, E. pseudoavium, E. malodoratus) and they differentiated both species from each other as well. Although all strains were isolated from different sampling sites, many strains shared the same band patterns. E. moraviensis formed four ribogroups using EcoRI and two ribogroups using HindIII restriction enzyme. E. haemoperoxidus gave six different patterns with EcoRI and five using the HindIII restriction enzyme.
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Affiliation(s)
- P Svec
- Czech Collection of Microorganisms, Faculty of Science, Masaryk University, Tvrdého 14, 602 00 Brno, Czech Republic.
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24
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Bertolatti D, Munyard SJ, Grubb WB, Binns CW. Thermal inactivation of antimicrobial-resistant Gram-positive cocci in chicken meat: D and Z value determinations. INTERNATIONAL JOURNAL OF ENVIRONMENTAL HEALTH RESEARCH 2001; 11:257-266. [PMID: 11672482 DOI: 10.1080/09603120120070874] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Antimicrobial-resistance in Gram-positive bacteria is reported with increasing frequency in strains isolated from food animals. Their isolation from commercial poultry carcasses and meat products constitute a potential risk that resistant strains or resistance genes might spread to humans via the food chain. As bacterial inactivation by thermal process is a critical control point in the safe preparation of many ready-to-eat foods, it is important to determine the thermal resistance of these organisms. The present study was undertaken to investigate the thermal tolerance (D and Z values) of antimicrobial-resistant, Gram-positive cocci in ground chicken meat. The antimicrobial-resistant, Gram-positive cocci for this study were isolated from two poultry processing plants in Western Australia. D and Z value data indicate that these isolates do not exhibit enhanced thermal resistant characteristics. The estimated lethal effect of the cooking process for chicken meat indicates that an internal temperature of 70 degrees C for 2.1 min would provide a 7-log reduction of all cell suspensions tested.
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Affiliation(s)
- D Bertolatti
- School of Public Health, Curtin University of Technology, GPO Box U1987 Perth, Western Australia 6845.
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25
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Boojamra CG, Lemoine RC, Lee JC, Léger R, Stein KA, Vernier NG, Magon A, Lomovskaya O, Martin PK, Chamberland S, Lee MD, Hecker SJ, Lee VJ. Stereochemical elucidation and total synthesis of dihydropacidamycin D, a semisynthetic pacidamycin. J Am Chem Soc 2001; 123:870-4. [PMID: 11456620 DOI: 10.1021/ja003292c] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Hydrogenation of the C(4') exocyclic olefin of the pacidamycins has been shown to produce a series of semisynthetic compounds, the dihydropacidamycins, with antimicrobial activity similar to that of the natural products. Elucidation of stereochemistry in the pacidamycins has been completed through a campaign of natural product degradation experiments in combination with the total synthesis of the lowest-molecular weight dihydropacidamycin, dihydropacidamycin D. The stereochemical identities of the tryptophan and two alanine residues contained in pacidamycin D have been shown to be of the natural (S) configuration, and the unique 3-methylamino-2-aminobutyric acid contained in this series of antibiotics has been shown to be of the (2S,3S) configuration. Finally, the stereochemistry obtained by hydrogenation of the C(4')-C(5') exocyclic olefin has been shown to be (R) at the C(4') nucleoside site.
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Affiliation(s)
- C G Boojamra
- Microcide Pharmaceuticals, Inc., 850 Maude Avenue, Mountain View, California 94043, USA
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26
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Abstract
Widespread resistance problems exist today in a global sense because of the incorporation of antibiotics with a high resistance potential into animal feeds and because of the uncontrolled use of antibiotics with a high resistance potential in the clinical setting. The only proven method of controlling nonoutbreak resistance problems in hospitals is to limit the hospital formulary to antibiotics with little or no resistance potential. The control of multiresistant organisms in outbreaks occurring in hospitals is best contained using appropriate infection control containment measures. Physicians treating infections in the community, with all other factors being equal, should preferentially select antibiotics with a low resistance potential. The titles and headings of much of the resistance literature are misleading. Articles should not contain fluoroquinolone resistant in the title when ciprofloxacin-resistant organisms are described. Many articles concerning penicillin-resistant pneumococci are entitled fluoroquinolone-resistant S. pneumoniae. These articles describe ciprofloxacin-resistant S. pneumoniae and not resistance to other fluoroquinolones. The same error is perpetuated in describing third-generation cephalosporins and carbapenems. Virtually all of the resistance problems associated with third-generation cephalosporins and carbapenems are due to ceftazidime or imipenem. More precise titling in the literature would remind physicians that antibiotic resistance is related to a specific agent and not class phenomena.
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Affiliation(s)
- B A Cunha
- Infectious Disease Division, Winthrop-University Hospital, Mineola, New York, USA
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27
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Sahly H, Podschun R, Ullmann U. Klebsiella infections in the immunocompromised host. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2000; 479:237-49. [PMID: 10897425 DOI: 10.1007/0-306-46831-x_21] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- H Sahly
- Department of Medical Microbiology and Virology, Christians-Albrechts-University of Kiel, Germany
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28
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Esposito S. Parenteral cephalosporin therapy in ambulatory care: advantages and disadvantages. Drugs 2000; 59 Suppl 3:19-28; discussion 47-9. [PMID: 10845410 DOI: 10.2165/00003495-200059003-00003] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Outpatient parenteral antibiotic therapy (OPAT) programmes are effective, well tolerated and economically advantageous in carefully selected patient populations. Inclusion criteria for patient selection for OPAT include good clinical appearance and uncomplicated infection. By virtue of their favourable microbiological and pharmacological properties, cephalosporins in general, and ceftriaxone in particular, are the most widely prescribed antibiotics for OPAT worldwide. OPAT was largely created to prolong parenteral therapy following early discharge and has now been extended to community general practice. Indeed, more than 250000 treatments are performed in the US each year for a wide variety of serious infections, with an increase of 100% during the last 5 years. In 1994, an advisory committee was created in Canada to provide guidelines for home intravenous therapy. Of the 3 models that were defined (the visiting nurse model, the infusion centre model and the self-administration model), the OPAT self-administration model offers considerable cost savings and is probably largely utilised in a number of countries, such as Italy, where specific models have not been codified. Once the need for parenteral antibiotic therapy has been established, the choice of antibiotic is the second step in the decision-making process. Third generation cephalosporins are characterised by a number of important advantages in the OPAT setting, namely a favourable antibacterial spectrum, tolerability profile and patient compliance, as well as advantageous cost considerations. While the advantages of parenteral cephalosporin therapy in the ambulatory care setting outweigh the disadvantages in terms of cost effectiveness and rapid onset of action, adverse events such as pain at the injection site following intramuscular administration and phlebitis after intravenous infusion should be borne in mind.
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Affiliation(s)
- S Esposito
- Institute of Infectious Diseases, Second University of Naples, Italy
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29
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Fong WK, Modrusan Z, McNevin JP, Marostenmaki J, Zin B, Bekkaoui F. Rapid solid-phase immunoassay for detection of methicillin-resistant Staphylococcus aureus using cycling probe technology. J Clin Microbiol 2000; 38:2525-9. [PMID: 10878037 PMCID: PMC86959 DOI: 10.1128/jcm.38.7.2525-2529.2000] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A Cycling Probe Technology (CPT) assay with a lateral-flow device (strip) was developed for the detection of the mecA gene from methicillin-resistant Staphylococcus aureus (MRSA) cultures. The assay uses a mecA probe (DNA-RNA-DNA) labeled with fluorescein at the 5' terminus and biotin at the 3' terminus. The CPT reaction occurs at a constant temperature, which allows the probe to anneal to the target DNA. RNase H cuts the RNA portion of the probe, allowing the cleaved fragments to dissociate from the target DNA, making the target available for further cycling. The strip detection step uses a nitrocellulose membrane with streptavidin and immunoglobulin G antibody impregnated on the surface. In the absence of the mecA gene, the uncut probe is bound to an antifluorescein-gold conjugate and is then captured by the streptavidin to form a test line. In the presence of the mecA gene, the probe is cut and no test line is formed on the strip. A screen of 324 S. aureus clinical isolates by the CPT-strip assay showed a 99.4% sensitivity and a 100% specificity compared to the results of PCR for the detection of the mecA gene. Specificity testing showed that the CPT-strip assay did not exhibit any cross-reactivity with a panel of mecA-negative non-S. aureus isolates. The CPT-strip assay is simple and does not require sophisticated equipment. Furthermore, the assay takes 1.5 h starting from a primary culture to the time to detection of the mecA gene in S. aureus isolates.
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Affiliation(s)
- W K Fong
- ID Biomedical Corp., Bothell, Washington 98011, USA
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30
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Abstract
The treatment of sepsis with i.v. immunoglobulins (IVIG) is currently regarded as not indicated. Several clinical studies, placebo controlled since 1985, to determine efficacy have failed to prevent fatal outcome, even when IVIG was given at high doses. The prevailing action mechanism put forward by most researchers is the capacity of specific antibodies contained in IVIG to bind to the infectious organism followed by opsonophagocytosis. Recently, IVIG preparations have been shown, both in vitro and in vivo, to profoundly affect the homeostasis of the cytokine network, probably in a way which directs this network from disturbed to regulated functioning. Excessive production and insufficient removal of cytokines due to multiorgan failure of sepsis patients are now known to play a decisive role in progression of sepsis to septic shock. There are researchers wondering whether the newly discovered influence of IVIG on cytokines might not be exploited for the design of improved study protocols, including better selection of the dosage, dosage schedule, association to other treatments and selection of patients. On the side of the IVIG preparations, improvements discussed include spiking of polyclonal preparations with monoclonal antibodies, selection of appropriate production lots and study of the efficacy not only of IgG but also of IgM isotype containing preparations.
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Affiliation(s)
- U E Nydegger
- Regional Red Cross Blood Transfusion Service SRC, Inselspital/University Hospital, Bern, Switzerland
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31
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Held TK, Jendrike NR, Rukavina T, Podschun R, Trautmann M. Binding to and opsonophagocytic activity of O-antigen-specific monoclonal antibodies against encapsulated and nonencapsulated Klebsiella pneumoniae serotype O1 strains. Infect Immun 2000; 68:2402-9. [PMID: 10768923 PMCID: PMC97438 DOI: 10.1128/iai.68.5.2402-2409.2000] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The high mortality of nosocomial infections caused by Klebsiella spp. has acted as a stimulus to develop immunotherapeutic approaches targeted against surface molecules of these bacteria. Since O-antigen-specific antibodies may add to the protective effect of K antisera, we tested the functional and binding capacity of O-antigen-specific monoclonal antibodies (MAbs) raised against different Klebsiella O antigens. The MAbs tested were specific for the O-polysaccharide partial antigens D-galactan II (MAb Ru-O1), D-galactan I (MAb IV/4-5), or core oligosaccharide (MAb V/9-5) of the Klebsiella serogroup O1 antigen. In enzyme-linked immunosorbent assay binding experiments, we found that all MAbs recognized their epitopes on intact capsule-free bacteria; however, binding to encapsulated wild-type strains belonging to different K-antigen serotypes was significantly reduced. The K2 antigen acted as the strongest penetration barrier, while the K7 and K21 antigens allowed some, though diminished, antibody binding. In vitro phagocytic killing experiments showed that MAb Ru-O1 possessed significant opsonizing activity for nonencapsulated O1 serogroup strains and also, to a much lesser extent, for encapsulated strains belonging to the O1:K7 and O1:K21 serotypes. MAbs or antisera specific for the D-galactan II antigen may thus be the most promising agents for further efforts to develop a second-generation Klebsiella hyperimmune globulin comprising both K- and O-antigen specificities.
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Affiliation(s)
- T K Held
- Department of Hematology and Oncology, Charité/Campus Virchow-Klinikum, Humboldt University, 13353 Berlin, Germany
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32
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Affiliation(s)
- D Isaacs
- New Children's Hospital, PO Box 3515, Parramatta, NSW 2124, Australia.
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33
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Bekkaoui F, McNevin JP, Leung CH, Peterson GJ, Patel A, Bhatt RS, Bryan RN. Rapid detection of the mecA gene in methicillin resistant staphylococci using a colorimetric cycling probe technology. Diagn Microbiol Infect Dis 1999; 34:83-90. [PMID: 10354856 DOI: 10.1016/s0732-8893(99)00012-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A Cycling Probe Technology (CPT) assay was developed for the detection of the mecA gene from methicillin resistant staphylococcal cultures. The assay is based on a colorimetric enzyme-immuno-assay (EIA) and uses a mecA probe (DNA-RNA-DNA) labeled with fluorescein at the 5'-terminus and biotin at the 3'-terminus. The reaction occurs at a constant temperature that allows the target DNA to anneal to the probe. RNase H cuts the RNA portion, allowing the cut fragments to dissociate from the target, making it available for further cycling. CPT-EIA uses streptavidin-coated microplate wells to capture uncut probe followed by detection with horseradish-peroxidase conjugated anti-fluorescein antibody. The assay was compared to PCR and shown to accurately detect the presence or absence of the mecA gene in 159 staphylococcal clinical isolates. The CPT-EIA assay takes two hours starting from cultured cells compared with the 24-48 h required for detection of methicillin resistance by conventional susceptibility tests.
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Affiliation(s)
- F Bekkaoui
- ID Biomedical Corporation, Burnaby, B.C., Canada
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34
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Slater M, Krug SE. Evaluation of the infant with fever without source: an evidence based approach. Emerg Med Clin North Am 1999; 17:97-126, viii-ix. [PMID: 10101343 DOI: 10.1016/s0733-8627(05)70049-3] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The infant with fever without an obvious source upon physical examination offers a challenging clinical problem. A combination of detailed history, physical examination, and selected laboratory tests allows the clinician to discern which infants are at lower risk for bacterial illness. Implications for management and future research are discussed herein.
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Affiliation(s)
- M Slater
- Division of Emergency Medicine, Northwestern University Medical School, Chicago, Illinois, USA
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35
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Royle J, Halasz S, Eagles G, Gilbert G, Dalton D, Jelfs P, Isaacs D. Outbreak of extended spectrum beta lactamase producing Klebsiella pneumoniae in a neonatal unit. Arch Dis Child Fetal Neonatal Ed 1999; 80:F64-8. [PMID: 10325816 PMCID: PMC1720890 DOI: 10.1136/fn.80.1.f64] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
An outbreak of extended spectrum beta lactamase producing Klebsiella pneumoniae (ESBLKp) in a neonatal unit was controlled using simple measures. Normally, the control of such infections can be time consuming and expensive. Seven cases of septicaemia resulted in two deaths. ESBLKp isolates were subtyped by pulsed field gel electrophoresis, and four of the five isolates typed were identical. Control of the outbreak was achieved by altered empiric antibiotic treatment for late onset sepsis and prevention of cross infection by strict attention to hand washing. Widespread colonisation of babies in the unit was presumed, so initial surveillance cultures were not performed. No further episodes of sepsis occurred.
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Affiliation(s)
- J Royle
- Department of Immunology and Infectious Diseases, Royal Alexandra Hospital for Children, NSW, Australia
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36
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Barrett R, Kuzawa CW, McDade T, Armelagos GJ. EMERGING AND RE-EMERGING INFECTIOUS DISEASES: The Third Epidemiologic Transition. ANNUAL REVIEW OF ANTHROPOLOGY 1998. [DOI: 10.1146/annurev.anthro.27.1.247] [Citation(s) in RCA: 244] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
▪ Abstract We use an expanded framework of multiple epidemiologic transitions to review the issues of re/emerging infection. The first epidemiologic transition was associated with a rise in infectious diseases that accompanied the Neolithic Revolution. The second epidemiologic transition involved the shift from infectious to chronic disease mortality associated with industrialization. The recent resurgence of infectious disease mortality marks a third epidemiologic transition characterized by newly emerging, re- emerging, and antibiotic resistant pathogens in the context of an accelerated globalization of human disease ecologies. These transitions illustrate recurring sociohistorical and ecological themes in human–disease relationships from the Paleolithic Age to the present day.
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Affiliation(s)
- Ronald Barrett
- Department of Anthropology, Emory University, Atlanta, Georgia 30322
| | | | - Thomas McDade
- Department of Anthropology, Emory University, Atlanta, Georgia 30322
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37
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Podschun R, Ullmann U. Klebsiella spp. as nosocomial pathogens: epidemiology, taxonomy, typing methods, and pathogenicity factors. Clin Microbiol Rev 1998; 11:589-603. [PMID: 9767057 PMCID: PMC88898 DOI: 10.1128/cmr.11.4.589] [Citation(s) in RCA: 1592] [Impact Index Per Article: 61.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Bacteria belonging to the genus Klebsiella frequently cause human nosocomial infections. In particular, the medically most important Klebsiella species, Klebsiella pneumoniae, accounts for a significant proportion of hospital-acquired urinary tract infections, pneumonia, septicemias, and soft tissue infections. The principal pathogenic reservoirs for transmission of Klebsiella are the gastrointestinal tract and the hands of hospital personnel. Because of their ability to spread rapidly in the hospital environment, these bacteria tend to cause nosocomial outbreaks. Hospital outbreaks of multidrug-resistant Klebsiella spp., especially those in neonatal wards, are often caused by new types of strains, the so-called extended-spectrum-beta-lactamase (ESBL) producers. The incidence of ESBL-producing strains among clinical Klebsiella isolates has been steadily increasing over the past years. The resulting limitations on the therapeutic options demand new measures for the management of Klebsiella hospital infections. While the different typing methods are useful epidemiological tools for infection control, recent findings about Klebsiella virulence factors have provided new insights into the pathogenic strategies of these bacteria. Klebsiella pathogenicity factors such as capsules or lipopolysaccharides are presently considered to be promising candidates for vaccination efforts that may serve as immunological infection control measures.
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Affiliation(s)
- R Podschun
- Department of Medical Microbiology and Virology, University of Kiel, Kiel, Germany.
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Low DE. Resistance issues and treatment implications: pneumococcus, Staphylococcus aureus, and gram-negative rods. Infect Dis Clin North Am 1998; 12:613-30, viii. [PMID: 9779381 DOI: 10.1016/s0891-5520(05)70201-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
During the last decade there has been an unexpectedly rapid evolution of antimicrobial resistance in the respiratory pathogens for community- and hospital-acquired pneumonia. In order to choose the most optimal therapy for their patients, it is essential that physicians be aware of the prevalence and mechanisms of resistance and their implications on the effectiveness of the various antimicrobials.
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Affiliation(s)
- D E Low
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Ontario, Canada
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Panaite DM, Tolmasky ME. Characterization of mutants of the 6'-N-acetyltransferase encoded by the multiresistance transposon Tn1331: effect of Phen171-to-Leu171 and Tyr80-to-Cys80 substitutions. Plasmid 1998; 39:123-33. [PMID: 9514709 DOI: 10.1006/plas.1997.1330] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The Klebsiella pneumoniae plasmid pJHCMW1 harbors a copy of Tn1331, a multiresistance transposon that includes the aac(6')-Ib gene which encodes a 6'-N-aminoglycoside acetyltransferase. This gene was mutagenized using the mutator Escherichia coli XL1-Red. Two plasmids with a single nucleotide mutation in aac(6')-Ib were selected for further analysis: pDP1 and pDP6. Plasmid pDP1 codes for a mutant enzyme, AAC(6')-IbDP1, that has the Phe171 replaced by a Leu residue. This mutant derivative showed a lower specific activity than the wild-type enzyme when either kanamycin (Km) or its semisynthetic derivative amikacin (Ak) were used as substrates in enzymatic assays performed at 30 degrees C. Furthermore, AAC(6')-IbDP1 showed a change of specificity of substrate when incubated at 42 degrees C. While its acetylating activity for Km was higher at this temperature than at 30 degrees C, it had its ability to utilize Ak as substrate for acetylation considerably reduced. Accordingly, minimal inhibitory concentration assays showed that E. coli(pDP1) was resistant to Ak at 37 degrees C but susceptible at 42 degrees C. The same assays showed that E. coli(pDP1) was highly resistant to Km at either 37 degrees C or 42 degrees C. A high level of resistance to Ak was observed for E. coli(pJHCMW1) which harbors the wild-type AAC(6')-Ib at either 37 or 42 degrees C. Extension of the analyses to other aminoglycosides showed that the enzymatic activity of AAC(6')-IbDP1 as well as the E. coli(pDP1) MICs for netilmicin dropped at 42 degrees C as was the case for Ak. These results could indicate that at 42 degrees C the mutant adopts a conformation that makes it unable to efficiently acetylate aminoglycoside molecules substituted in the C-1amino group of the deoxystreptamine moiety. Plasmid pDP6 encodes the mutant AAC(6')-IbDP6 which has the Tyr80 substituted by a Cys residue. E. coli(pDP6) exhibited reduced MICs for Ak, Km, tobramycin, and netilmicin. Analysis of the acetylating activity of AAC(6')-IbDP6 showed only marginal levels of activity when either Ak, Km, tobramycin, or netilmicin were used as substrates.
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Affiliation(s)
- D M Panaite
- Department of Biological Science, School of Natural Sciences and Mathematics, California State University Fullerton, California 92834-6850, USA
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Bonhoeffer S, Lipsitch M, Levin BR. Evaluating treatment protocols to prevent antibiotic resistance. Proc Natl Acad Sci U S A 1997; 94:12106-11. [PMID: 9342370 PMCID: PMC23718 DOI: 10.1073/pnas.94.22.12106] [Citation(s) in RCA: 317] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/1997] [Indexed: 02/05/2023] Open
Abstract
The spread of bacteria resistant to antimicrobial agents calls for population-wide treatment strategies to delay or reverse the trend toward antibiotic resistance. Here we propose new criteria for the evaluation of the population-wide effects of treatment protocols for directly transmitted bacterial infections and discuss different usage patterns for single and multiple antibiotic therapy. A mathematical model suggests that the long-term benefit of single drug treatment from introduction of the antibiotic until a high frequency of resistance precludes its use is almost independent of the pattern of antibiotic use. When more than one antibiotic is employed, sequential use of different antibiotics in the population ("cycling") is always inferior to treatment strategies where, at any given time, equal fractions of the population receive different antibiotics. However, treatment of all patients with a combination of antibiotics is in most cases the optimal treatment strategy.
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Affiliation(s)
- S Bonhoeffer
- Wellcome Trust Centre for the Epidemiology of Infectious Disease, Department of Zoology, University of Oxford, South Parks Road, Oxford, OX1 3PS, United Kingdom
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Di Martino P, Sirot D, Joly B, Rich C, Darfeuille-Michaud A. Relationship between adhesion to intestinal Caco-2 cells and multidrug resistance in Klebsiella pneumoniae clinical isolates. J Clin Microbiol 1997; 35:1499-503. [PMID: 9163469 PMCID: PMC229774 DOI: 10.1128/jcm.35.6.1499-1503.1997] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Klebsiella pneumoniae is an opportunistic gram-negative pathogen involved in outbreaks of nosocomial infections in intensive care units. Strains are resistant to multiple antibiotics, and 15 to 30% of them are also resistant to the broad-spectrum cephalosporins by the production of R plasmid-encoded extended-spectrum beta-lactamases. Because the gastrointestinal tracts of patients have been shown to be the reservoir for nosocomial strains of K. pneumoniae, we looked for a correlation between antibiotic resistance and adhesion of K. pneumoniae strains to intestinal cells. We investigated adhesion to the human intestinal epithelial Caco-2 cell line of 61 clinical K. pneumoniae strains isolated in hospitals in Clermont-Ferrand, France. None of the strains tested expressed the previously described adhesive factors CF29K and KPF-28. Adhesive properties were found for 42.6% of the strains tested (26 strains). Just 7.7% (2 strains) of the 26 strains producing only the chromosomally encoded SHV-1 beta-lactamase adhered to the Caco-2 cell line, whereas 68.5% (24 strains) of the 35 strains producing a plasmid-encoded beta-lactamase were adherent. All the adherent strains, and even the two strains producing only the SHV-1 enzyme, harbored at least one self-transmissible R plasmid. At variance for CAZ-1/TEM-5 or CAZ-5/SHV-4 beta-lactamase-producing K. pneumoniae strains, curing and mating experiments demonstrated that the self-transmissible R plasmids encoding the TEM-1, CTX-1/TEM-3, CAZ-2/TEM-8, CAZ-6/TEM-24, or CAZ-7/TEM-16 beta-lactamase were not involved in the adhesion of K. pneumoniae strains to intestinal epithelial cells. Nevertheless, there was an association of multiple antibiotic resistance, including resistance to extended-spectrum cephalosporins, and adhesive properties in K. pneumoniae clinical isolates.
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Affiliation(s)
- P Di Martino
- Laboratoire de Bactériologie, Faculté de Pharmacie, Clermont-Ferrand,France
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Antibiotics for treatment of infections caused by MRSA and elimination of MRSA carriage. What are the choices? Int J Antimicrob Agents 1997; 9:1-19. [DOI: 10.1016/s0924-8579(97)00027-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/28/1997] [Indexed: 11/15/2022]
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Wright GD, Ladak P. Overexpression and characterization of the chromosomal aminoglycoside 6'-N-acetyltransferase from Enterococcus faecium. Antimicrob Agents Chemother 1997; 41:956-60. [PMID: 9145851 PMCID: PMC163832 DOI: 10.1128/aac.41.5.956] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The chromosomal gene aac(6')-Ii, encoding an aminoglycoside 6'-N-acetyltransferase in Enterococcus faecium, renders this organism resistant to moderate levels of many aminoglycoside antibiotics. The ubiquitous presence of aac(6')-Ii in E. faecium complicates the selection of antibiotics for treatment of infections caused by this organism. In view of the importance of this enzyme, we have initiated studies to gain an understanding of its molecular mechanism of acetyl transfer. The AAC(6')-Ii enzyme was overexpressed in Escherichia coli and purified in a simple three-step procedure which yields 55 mg of pure dimeric protein per liter of cell culture. Steady-state kinetic analyses revealed a broad substrate specificity and demonstrated that acetylation occurs exclusively at position N-6'. k(cat)/Km values were on the order of 10(4) M(-1) s(-1), which is relatively low compared to other aminoglycoside-modifying enzymes. In addition, MIC values were positively correlated with k(cat), the rate when the enzyme is saturated with the aminoglycoside substrate, and not with k(cat)/Km, the rate at low aminoglycoside (sub-Km) concentrations. These results describe an enzyme which is not optimally evolved for aminoglycoside inactivation and suggest that this chromosomally encoded enzyme may have an alternate physiological function.
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Affiliation(s)
- G D Wright
- Department of Biochemistry, McMaster University, Hamilton, Ontario, Canada.
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Medeiros AA, Crellin J. Comparative susceptibility of clinical isolates producing extended spectrum beta-lactamases to ceftibuten: effect of large inocula. Pediatr Infect Dis J 1997; 16:S49-55. [PMID: 9076836 DOI: 10.1097/00006454-199703001-00005] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Infections caused by Enterobacteriaceae producing extended-spectrum beta-lactamases (ESBLs) are a growing clinical problem. However, there is wide variation in the level of resistance to third generation beta-lactams conferred by these enzymes. METHODS We studied 33 Klebsiella pneumoniae and 4 Escherichia coli isolates producing ESBLs obtained from outbreaks in 14 different hospitals and a nursing home in the United States. Microdilution testing with standard (10(4-5) colony-forming units/ml) and large (10(6-7) colony-forming units/ml) inocula, was used to compare the minimum inhibitory concentrations (MICs) of ceftibuten, a novel oral oxyimino beta-lactam, with those of other third generation beta-lactams (cefotaxime, ceftazidime, aztreonam, cefixime, cefpodoxime and cefoxitin). RESULTS Twenty-seven of the clinical isolates had well-characterized ESBLs of 10 different types, 7 of which produced TEM-1; 1 isolate also produced LXA-1. Two strains produced more than 1 ESBL. The remaining 10 strains produced 8 as yet uncharacterized types of ESBL. With large inocula 73% tested susceptible to ceftibuten, whereas 8 to 22% tested susceptible to the other third generation beta-lactam antibiotics. Ceftibuten MICs increased with higher inocula when tested against strains producing SHV-4 or SHV-5 and, to a lesser extent, strains producing multiple beta-lactamases. Only cefoxitin showed a smaller inoculum effect. CONCLUSION Ceftibuten merits clinical evaluation in infections caused by bacteria that produce ESBLs.
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