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Biofilm production by Candida: comparison of bloodstream isolates with cervical isolates. Indian J Microbiol 2012; 52:504-6. [PMID: 23997348 DOI: 10.1007/s12088-012-0261-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2011] [Accepted: 03/01/2012] [Indexed: 10/28/2022] Open
Abstract
The present study was undertaken to investigate biofilm formation among the clinical Candida isolates from blood and cervical swabs. A total of 16 Candida blood isolates from neonates and 21 cervical isolates from pregnant women with vulvovaginitis were included in the study. Each isolate was identified to species level by various phenotypic tests. Biofilm formation was detected by colorimetric method. C. glabrata and C. albicans were the major isolates from blood and cervical swab respectively. The biofilm formation was found in 14 (87.5 %) blood isolates and only in 4 (19.1 %) cervical isolates.
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Smith AR, Macfarlane GT, Reynolds N, O'May GA, Bahrami B, Macfarlane S. Effect of a synbiotic on microbial community structure in a continuous culture model of the gastric microbiota in enteral nutrition patients. FEMS Microbiol Ecol 2012; 80:135-45. [DOI: 10.1111/j.1574-6941.2011.01279.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Revised: 12/02/2011] [Accepted: 12/05/2011] [Indexed: 01/22/2023] Open
Affiliation(s)
- Aileen R. Smith
- Microbiology and Gut Biology Group; University of Dundee; Ninewells Hospital and Medical School; Dundee; UK
| | - George T. Macfarlane
- Microbiology and Gut Biology Group; University of Dundee; Ninewells Hospital and Medical School; Dundee; UK
| | - Nigel Reynolds
- Department of Gastroenterology; Ninewells Hospital and Medical School; Dundee; UK
| | - Graeme A. O'May
- Microbiology and Gut Biology Group; University of Dundee; Ninewells Hospital and Medical School; Dundee; UK
| | - Bahram Bahrami
- Microbiology and Gut Biology Group; University of Dundee; Ninewells Hospital and Medical School; Dundee; UK
| | - Sandra Macfarlane
- Microbiology and Gut Biology Group; University of Dundee; Ninewells Hospital and Medical School; Dundee; UK
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Peters BM, Jabra-Rizk MA, O'May GA, Costerton JW, Shirtliff ME. Polymicrobial interactions: impact on pathogenesis and human disease. Clin Microbiol Rev 2012; 25:193-213. [PMID: 22232376 PMCID: PMC3255964 DOI: 10.1128/cmr.00013-11] [Citation(s) in RCA: 464] [Impact Index Per Article: 38.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Microorganisms coexist in a complex milieu of bacteria, fungi, archaea, and viruses on or within the human body, often as multifaceted polymicrobial biofilm communities at mucosal sites and on abiotic surfaces. Only recently have we begun to appreciate the complicated biofilm phenotype during infection; moreover, even less is known about the interactions that occur between microorganisms during polymicrobial growth and their implications in human disease. Therefore, this review focuses on polymicrobial biofilm-mediated infections and examines the contribution of bacterial-bacterial, bacterial-fungal, and bacterial-viral interactions during human infection and potential strategies for protection against such diseases.
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Affiliation(s)
- Brian M. Peters
- Graduate Program in Life Sciences, Molecular Microbiology and Immunology Program, University of Maryland—Baltimore, Baltimore, Maryland, USA
- Department of Microbial Pathogenesis, University of Maryland—Baltimore, Dental School, Baltimore, Maryland, USA
| | - Mary Ann Jabra-Rizk
- Department of Oncology and Diagnostic Sciences, Dental School, University of Maryland—Baltimore, Baltimore, Maryland, USA
- Department of Microbiology and Immunology, School of Medicine, University of Maryland—Baltimore, Baltimore, Maryland, USA
| | - Graeme A. O'May
- Department of Microbial Pathogenesis, University of Maryland—Baltimore, Dental School, Baltimore, Maryland, USA
| | - J. William Costerton
- Department of Orthopedic Surgery, Center for Genomic Sciences, Allegheny-Singer Research Institute, Allegheny General Hospital, Pittsburgh, Pennsylvania, USA
| | - Mark E. Shirtliff
- Department of Microbial Pathogenesis, University of Maryland—Baltimore, Dental School, Baltimore, Maryland, USA
- Department of Microbiology and Immunology, School of Medicine, University of Maryland—Baltimore, Baltimore, Maryland, USA
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Prevalence, phenotype, and genotype of Enterococcus faecalis isolated from saliva and root canals in patients with persistent apical periodontitis. J Endod 2010; 36:1950-5. [PMID: 21092811 DOI: 10.1016/j.joen.2010.08.053] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2010] [Revised: 08/27/2010] [Accepted: 08/28/2010] [Indexed: 11/21/2022]
Abstract
INTRODUCTION The aim of this study was to investigate the prevalence, phenotype, and genotype of Enterococcus faecalis isolated from saliva and root canals in patients with endodontic treatment failure. METHODS Samples were collected from 32 adults undergoing retreatment for periapical lesions after endodontic treatment performed at least 2 years previously. Isolates that were presumed to be E. faecalis were identified by both API20 Strep kits and 16S rRNA sequencing. Phenotypic tests for hemolysin and gelatinase production and antibiotic susceptibility were performed. Genotype analysis comprised virulence gene detection and pulsed field gel electrophoresis (PFGE). RESULTS The prevalence of E. faecalis was 18.8% in saliva and 40.6% in root canals (P = .666, Fisher exact test). Of the 19 isolates of E. faecalis, 6 were from saliva and 13 were from root canals. In 3 patients, E. faecalis isolates from saliva were more resistant to gentamicin than those from root canals. The genes ace, asa, gelE, cylA, and efaA were detected from all isolates. PFGE after SmaI digestion showed a genetic correlation among all isolates of 62%-100%. CONCLUSIONS Phenotype and genotype evidence of potential virulence factors was identified in E. faecalis from both saliva and root canals. A single patient might carry different E. faecalis strains in saliva and root canals.
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Gajbhiye A, Rai AR, Meshram SU, Dongre AB. Isolation, evaluation and characterization of Bacillus subtilis from cotton rhizospheric soil with biocontrol activity against Fusarium oxysporum. World J Microbiol Biotechnol 2009; 26:1187-94. [PMID: 24026922 DOI: 10.1007/s11274-009-0287-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2009] [Accepted: 12/14/2009] [Indexed: 11/29/2022]
Abstract
Present investigation is based on the isolation of Bacillus subtilis from cotton rhizosphere and their evaluation as biocontrol agent against Fusarium oxysporum. The production of extracellular hydrolytic enzyme was studied for determining the antagonism. 43% of 21 isolates were identified under the B. subtilis group on the basis of biochemical characterization. 38% isolates showed competitive activity against Fusarium oxysporum and exhibit more than 50% mycelial inhibition in dual culture bioassay. The pot assay of cotton by seed treatment and soil amendment technique under green house condition showed the competent activity of the isolates in preventing the wilting of cotton seedlings due to F. oxysporum infection. SVI values of 30 day old seedlings indicated that the soil inoculation with B. subtilis BP-2 and seed treatment with B. subtilis BP-9 significantly promoted the growth of cotton seedlings. RAPD profiling revealed the diversity in the Bacillus subtilis group, ranging from 10 to 32%. The discriminative pattern among the isolates belonging to the same species was validated by 16S rDNA partial sequencing which identified them into four different strains of B. subtilis.
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Affiliation(s)
- Archana Gajbhiye
- Department of Microbiology, R.T.M. Nagpur University, L.I.T. Premises, Amravati Road, Nagpur, Maharashtra, 440033, India,
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SgrA, a nidogen-binding LPXTG surface adhesin implicated in biofilm formation, and EcbA, a collagen binding MSCRAMM, are two novel adhesins of hospital-acquired Enterococcus faecium. Infect Immun 2009; 77:5097-106. [PMID: 19737906 DOI: 10.1128/iai.00275-09] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Hospital-acquired Enterococcus faecium isolates responsible for nosocomial outbreaks and invasive infections are enriched in the orf2351 and orf2430 genes, encoding the SgrA and EcbA LPXTG-like cell wall-anchored proteins, respectively. These two surface proteins were characterized to gain insight into their function, since they may have favored the rapid emergence of this nosocomial pathogen. We are the first to identify a surface adhesin among bacteria (SgrA) that binds to the extracellular matrix molecules nidogen 1 and nidogen 2, which are constituents of the basal lamina. EcbA is a novel E. faecium MSCRAMM (microbial surface component recognizing adhesive matrix molecules) that binds to collagen type V. In addition, both SgrA and EcbA bound to fibrinogen; however, SgrA targeted the alpha and beta chains, whereas EcbA bound to the gamma chain of fibrinogen. An E. faecium sgrA insertion mutant displayed reduced binding to both nidogens and fibrinogen. SgrA did not mediate binding of E. faecium cells to biotic materials, such as human intestinal epithelial cells, human bladder cells, and kidney cells, while this LPXTG surface adhesin is implicated in E. faecium biofilm formation. The acm and scm genes, encoding two other E. faecium MSCRAMMs, were expressed at the mRNA level together with sgrA during all phases of growth, whereas ecbA was expressed only in exponential and late exponential phase, suggesting orchestrated expression of these adhesins. Expression of these surface proteins, which bind to extracellular matrix proteins and are involved in biofilm formation (SgrA), may contribute to the pathogenesis of hospital-acquired E. faecium infections.
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Heikens E, Leendertse M, Wijnands LM, van Luit-Asbroek M, Bonten MJM, van der Poll T, Willems RJL. Enterococcal surface protein Esp is not essential for cell adhesion and intestinal colonization of Enterococcus faecium in mice. BMC Microbiol 2009; 9:19. [PMID: 19178704 PMCID: PMC2639590 DOI: 10.1186/1471-2180-9-19] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2008] [Accepted: 01/29/2009] [Indexed: 11/30/2022] Open
Abstract
Background Enterococcus faecium has globally emerged as a cause of hospital-acquired infections with high colonization rates in hospitalized patients. The enterococcal surface protein Esp, identified as a potential virulence factor, is specifically linked to nosocomial clonal lineages that are genetically distinct from indigenous E. faecium strains. To investigate whether Esp facilitates bacterial adherence and intestinal colonization of E. faecium, we used human colorectal adenocarcinoma cells (Caco-2 cells) and an experimental colonization model in mice. Results No differences in adherence to Caco-2 cells were found between an Esp expressing strain of E. faecium (E1162) and its isogenic Esp-deficient mutant (E1162Δesp). Mice, kept under ceftriaxone treatment, were inoculated orally with either E1162, E1162Δesp or both strains simultaneously. Both E1162 and E1162Δesp were able to colonize the murine intestines with high and comparable numbers. No differences were found in the contents of cecum and colon. Both E1162 and E1162Δesp were able to translocate to the mesenteric lymph nodes. Conclusion These results suggest that Esp is not essential for Caco-2 cell adherence and intestinal colonization or translocation of E. faecium in mice.
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Affiliation(s)
- Esther Heikens
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, the Netherlands.
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Solseng T, Vinson H, Gibbs P, Greenwald B. In Vitro Formation of Biofilms on Lopez Enteral Feeding Valves: Implications for Critical Care Patients and Nurses. Crit Care Nurse 2008. [DOI: 10.4037/ccn2008.28.1.37] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Affiliation(s)
- Tracy Solseng
- Tracy Solseng is a graduate student working on a master’s degree in food safety at North Dakota State University in Fargo. She is studying the plasmids associated with Enterobacter sakazakii
| | - Heather Vinson
- Heather Vinson is a microbiologist working in Penelope Gibbs’ laboratory at the Great Plains Institute of Food Safety at North Dakota State University in Fargo
| | - Penelope Gibbs
- Heather Vinson is a microbiologist working in Penelope Gibbs’ laboratory at the Great Plains Institute of Food Safety at North Dakota State University in Fargo
- Penelope Gibbs is an assistant professor of infectious diseases at the Great Plains Institute of Food Safety at North Dakota State University in Fargo. She teaches courses in pathogenic microbiology, bacterial genetics and phage, and microbiological molecular techniques to both undergraduate and graduate students. She also trains undergraduate students on research techniques and hypothesis testing
| | - Beverly Greenwald
- Beverly Greenwald is an assistant professor of nursing at North Dakota State University in Fargo. She teaches undergraduate courses in nursing research and nursing management and does clinical rotations with students in adult health. Her research focus is gastroenterology nursing
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Heikens E, Bonten MJM, Willems RJL. Enterococcal surface protein Esp is important for biofilm formation of Enterococcus faecium E1162. J Bacteriol 2007; 189:8233-40. [PMID: 17827282 PMCID: PMC2168697 DOI: 10.1128/jb.01205-07] [Citation(s) in RCA: 158] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Enterococci have emerged as important nosocomial pathogens with resistance to multiple antibiotics. Adhesion to abiotic materials and biofilm formation on medical devices are considered important virulence properties. A single clonal lineage of Enterococcus faecium, complex 17 (CC17), appears to be a successful nosocomial pathogen, and most CC17 isolates harbor the enterococcal surface protein gene, esp. In this study, we constructed an esp insertion-deletion mutant in a clinical E. faecium CC17 isolate. In addition, initial adherence and biofilm assays were performed. Compared to the wild-type strain, the esp insertion-deletion mutant no longer produced Esp on the cell surface and had significantly lower initial adherence to polystyrene and significantly less biofilm formation, resulting in levels of biofilm comparable to those of an esp-negative isolate. Capacities for initial adherence and biofilm formation were restored in the insertion-deletion mutant by in trans complementation with esp. These results identify Esp as the first documented determinant in E. faecium CC17 with an important role in biofilm formation, which is an essential factor in infection pathogenesis.
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Affiliation(s)
- Esther Heikens
- Department of Medical Microbiology, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands.
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DeLegge RL, DeLegge MH. Percutaneous endoscopic gastrostomy evaluation of device materials: are we "failsafe"? Nutr Clin Pract 2006; 20:613-7. [PMID: 16306298 DOI: 10.1177/0115426505020006613] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The development of the percutaneous endoscopic gastrostomy (PEG) tube for enteral access was a revolutionary technological advance. This device has undergone some minor modification over the past 30 years but remains very similar to the original PEG tube design. Use of the PEG tube for gastric enteral feeding access continues to increase yearly both in pediatric and adult populations. One of the difficulties noted with PEG tube use in daily clinical practice is the ultimate degradation of the PEG tube wall material, leading to tube cracking, tearing, and leaking, requiring replacement of the gastrostomy tube. Historically, the predominant polymer material used for PEG tube composition was silicone. More recently, polyurethane has been examined as a potential, more durable material for PEG tube composition. Copolymers, or combinations of silicone and polyurethane and other polymer materials, are currently under investigation as the answer for the development of a bioinert, tissue-friendly, durable, PEG tube composition material.
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Haymore BR, Akers KS, Ferguson TM. A case of persistent Bacillus pumilis bacteremia associated with cholangitis. J Infect 2006; 52:154-5. [PMID: 15992931 DOI: 10.1016/j.jinf.2005.05.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2005] [Accepted: 05/11/2005] [Indexed: 11/15/2022]
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Abstract
The polymerase chain reaction (PCR) has become one of the most important tools in molecular diagnostics, providing exquisite sensitivity and specificity for detection of nucleic acid targets. Real-time monitoring of PCR has simplified and accelerated PCR laboratory procedures and has increased information obtained from specimens including routine quantification and differentiation of amplification products. Clinical diagnostic applications and uses of real-time PCR are growing exponentially, real-time PCR is rapidly replacing traditional PCR, and new diagnostic uses likely will emerge. This review analyzes the scope of present and potential future clinical diagnostic applications of this powerful technique. Critical discussions focus on basic concepts, variations, data analysis, instrument platforms, signal detection formats, sample collection, assay design, and execution of real-time PCR.
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Affiliation(s)
- Bernhard Kaltenboeck
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, Alabama, USA
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O'May GA, Reynolds N, Macfarlane GT. Effect of pH on an in vitro model of gastric microbiota in enteral nutrition patients. Appl Environ Microbiol 2005; 71:4777-83. [PMID: 16085875 PMCID: PMC1183347 DOI: 10.1128/aem.71.8.4777-4783.2005] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Patients with dysphagia due to oropharyngeal disease or cerebrovascular accident require long-term nutritional support via enteral feeding, which often results in microbial overgrowth in the upper gastrointestinal (GI) tract. Gastric acid is the primary innate defense mechanism in the stomach and has been assumed to provide an effective barrier to microbial colonization at pH values of <4. To evaluate the efficacy of gastric acid as a barrier to overgrowth, the microbiota of gastric and duodenal aspirates was assessed by culturing methods. Additionally, a fermentor-based model incorporating enteral nutrition tubing of the gastric microbiota of enteral nutrition (EN) patients was constructed to assess the effect of pH on the microbiota. Results showed that gastric acidity had a relatively small effect on the numbers of microorganisms recovered from intestinal aspirates but did influence microbiota composition. Similarly, at pH 3 in the fermentor, a complex microbiota developed in the planktonic phase and in biofilms. The effect of pH on microbiota composition was similar in aspirates and in the fermentors. Candidas and lactobacilli were aciduric, while recoveries of Escherichia coli and Klebsiella pneumoniae decreased as pH was reduced, although both were still present in significant numbers at pH 3. Only Staphylococcus aureus and Bifidobacterium adolescentis persisted at higher pH values both in vitro and in vivo. Lactate and acetate were the main organic acids detected in both aspirates and fermentors. These data show that the simulator used in this investigation was capable of modeling the effects of environmental influences on the upper GI microbiota of EN patients and that gastric pH of <4 is not sufficient to prevent microbial overgrowth in these individuals.
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Affiliation(s)
- Graeme A O'May
- Microbiology and Gut Biology Group, University of Dundee, Ninewells Hospital Medical School, Dundee DD1 9SY, Scotland, United Kingdom.
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O'May GA, Reynolds N, Smith AR, Kennedy A, Macfarlane GT. Effect of pH and antibiotics on microbial overgrowth in the stomachs and duodena of patients undergoing percutaneous endoscopic gastrostomy feeding. J Clin Microbiol 2005; 43:3059-65. [PMID: 16000416 PMCID: PMC1169167 DOI: 10.1128/jcm.43.7.3059-3065.2005] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Enteral nutrition via a percutaneous endoscopic gastrostomy (PEG) tube is often part of management in patients with dysphagia due to neurological or oropharyngeal disease. Gastrostomy placement can affect normal innate defense mechanisms in the upper gut, resulting in bacterial overgrowth. In this study microbiological investigations were done with gastric and duodenal aspirates from 20 patients undergoing PEG tube placement and PEG tubes from 10 patients undergoing tube replacement. Aspirate and PEG tube microbiotas were assessed by using viable counts and selective solid media followed by aerobic and anaerobic incubation to assess cell viabilities. The antibiotic susceptibility profiles of the isolates were determined by the disk diffusion method, and gas chromatography was used to study the bacterial metabolic products in the aspirates. The aspirates and PEG tubes contained mainly streptococci, staphylococci, lactobacilli, yeasts, and enterobacteria. Enterococci were detected only in PEG tube biofilms and not in aspirates. Gastric pH affected the composition of the aspirate microbiotas but not the total microbial counts. Staphylococci, Escherichia coli, and Candida spp. were isolated only from antibiotic-treated patients, despite the sensitivities of the bacteria to the agents used. Antibiotic treatment had no effect on the incidence of infection or the length of hospital stay in these patients.
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Affiliation(s)
- Graeme A O'May
- Microbiology and Gut Biology Group, University of Dundee, Ninewells Hospital Medical School, Dundee DD1 9SY, United Kingdom.
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Abstract
The polymerase chain reaction (PCR) has become one of the most important tools in molecular diagnostics, providing exquisite sensitivity and specificity for detection of nucleic acid targets. Real-time monitoring of PCR has simplified and accelerated PCR laboratory procedures and has increased information obtained from specimens including routine quantification and differentiation of amplification products. Clinical diagnostic applications and uses of real-time PCR are growing exponentially, real-time PCR is rapidly replacing traditional PCR, and new diagnostic uses likely will emerge. This review analyzes the scope of present and potential future clinical diagnostic applications of this powerful technique. Critical discussions focus on basic concepts, variations, data analysis, instrument platforms, signal detection formats, sample collection, assay design, and execution of real-time PCR.
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Affiliation(s)
- Bernhard Kaltenboeck
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, Alabama, USA
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Wang XM, Noble L, Kreiswirth BN, Eisner W, McClements W, Jansen KU, Anderson AS. Evaluation of a multilocus sequence typing system for Staphylococcus epidermidis. J Med Microbiol 2003; 52:989-998. [PMID: 14532344 DOI: 10.1099/jmm.0.05360-0] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Staphylococcus epidermidis is a significant cause of nosocomial disease. However, the taxonomy of this pathogen, particularly at subspecies level, is unclear. A multilocus sequence typing (MLST) scheme has therefore been investigated as a tool to elucidate taxonomic relationships within this group, based on genetic relatedness. DNA sequences for internal fragments of seven housekeeping genes were compared in 47 geographically and temporally diverse S. epidermidis isolates that were obtained from clinical infections. Twenty-three different allelic profiles were detected; 17 of these were represented by single strains and the largest profile group contained 17 isolates. Diversity of the same collection of isolates was investigated by using PFGE of SmaI-digested genomic DNA to test the discrimination and validity of the MLST approach. Isolates within the largest profile group were resolved into four distinct PFGE clusters on the basis of their SmaI digest patterns. Isolates within other profile groups that contained multiple isolates had matching PFGE SmaI patterns within each group. It appears that MLST is an effective method for grouping S. epidermidis strains at the subspecies level; however, it is not as discriminatory as it has been for other species for which MLST schemes have been established and, used alone, would not be a useful method for epidemiological studies. In addition, it was demonstrated that this method was effective for confirming the identity of S. epidermidis CoNS (coagulase-negative) isolates.
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Affiliation(s)
- Xin-Min Wang
- Merck and Co. Inc., PO Box 4 WP 26-265, Sumneytown Pike, West Point, PA 19486, USA 2Merck and Co. Inc., PO Box 2000 RY80Y 230, 126 E. Lincoln Ave., Rahway, NJ 07065, USA 3PHRI TB Center, Public Health Research Institute, 225 Warren Street, Newark, NJ 07103, USA
| | - Liliane Noble
- Merck and Co. Inc., PO Box 4 WP 26-265, Sumneytown Pike, West Point, PA 19486, USA 2Merck and Co. Inc., PO Box 2000 RY80Y 230, 126 E. Lincoln Ave., Rahway, NJ 07065, USA 3PHRI TB Center, Public Health Research Institute, 225 Warren Street, Newark, NJ 07103, USA
| | - Barry N Kreiswirth
- Merck and Co. Inc., PO Box 4 WP 26-265, Sumneytown Pike, West Point, PA 19486, USA 2Merck and Co. Inc., PO Box 2000 RY80Y 230, 126 E. Lincoln Ave., Rahway, NJ 07065, USA 3PHRI TB Center, Public Health Research Institute, 225 Warren Street, Newark, NJ 07103, USA
| | - William Eisner
- Merck and Co. Inc., PO Box 4 WP 26-265, Sumneytown Pike, West Point, PA 19486, USA 2Merck and Co. Inc., PO Box 2000 RY80Y 230, 126 E. Lincoln Ave., Rahway, NJ 07065, USA 3PHRI TB Center, Public Health Research Institute, 225 Warren Street, Newark, NJ 07103, USA
| | - William McClements
- Merck and Co. Inc., PO Box 4 WP 26-265, Sumneytown Pike, West Point, PA 19486, USA 2Merck and Co. Inc., PO Box 2000 RY80Y 230, 126 E. Lincoln Ave., Rahway, NJ 07065, USA 3PHRI TB Center, Public Health Research Institute, 225 Warren Street, Newark, NJ 07103, USA
| | - Kathrin U Jansen
- Merck and Co. Inc., PO Box 4 WP 26-265, Sumneytown Pike, West Point, PA 19486, USA 2Merck and Co. Inc., PO Box 2000 RY80Y 230, 126 E. Lincoln Ave., Rahway, NJ 07065, USA 3PHRI TB Center, Public Health Research Institute, 225 Warren Street, Newark, NJ 07103, USA
| | - Annaliesa S Anderson
- Merck and Co. Inc., PO Box 4 WP 26-265, Sumneytown Pike, West Point, PA 19486, USA 2Merck and Co. Inc., PO Box 2000 RY80Y 230, 126 E. Lincoln Ave., Rahway, NJ 07065, USA 3PHRI TB Center, Public Health Research Institute, 225 Warren Street, Newark, NJ 07103, USA
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Dautle MP, Wilkinson TR, Gauderer MWL. Isolation and identification of biofilm microorganisms from silicone gastrostomy devices. J Pediatr Surg 2003; 38:216-20. [PMID: 12596106 DOI: 10.1053/jpsu.2003.50046] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
BACKGROUND/PURPOSE Silicone gastrostomy devices (tubes and "buttons") are used extensively for long-term feeding and administration of special diets and medications. However, their potential for harboring microorganisms and possibly compromising the host largely is unknown. This study was conducted to isolate and identify the microbial species in viable biofilms attached to these devices in a pediatric cohort. METHODS A total of 78 domains on 18 silicone gastrostomy devices (12 "buttons" and 6 tubes converted to skin level devices), previously used for feeding (3 to 47 months) in children ranging in age from 6 months to 17 years were analyzed for microbial content. Biofilms were removed from the silicone tube surfaces and inoculated into enriched nutrient media using standard procedures. Intact biofilms also were observed using scanning electron microscopy (SEM) and confocal scanning laser microscopy. RESULTS All devices analyzed in this investigation were found to exhibit biofilm growth. Of the 24 identified bacterial species, the predominant genera included Bacillus, Enterococcus, and Staphylococcus. Control studies of the tubes under SEM showed a multitude of crevices serving as niches for microbial colonization. Observation of the attached biofilm by SEM showed various biomasses with numerous morphologies. CONCLUSIONS Biofilm composition and attachment to silicone enteral access devices has not received appropriate attention previously. This study shows that devices are colonized with various bacteria and fungi posing a potential threat to patients, particularly those who are immunocompromised. These microorganisms also may play a significant role in the formation of granulation tissue and contribute to device failure.
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Affiliation(s)
- Melanie P Dautle
- Department of Microbiology and Molecular Medicine, Clemson University, Clemson, SC, USA
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