SEARCH · PubMed Health

Results for “Staphylococcus epidermidis”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,441 records · Page 80Linked to original sources

PubMed1992

Bactericidal activities of rat defensins and synthetic rabbit defensins on Staphylococci, Klebsiella pneumoniae (Chedid, 277, and 8N3), Pseudomonas aeruginosa (mucoid and nonmucoid strains), Salmonella typhimurium (Ra, Rc, Rd, and Re of LPS mutants) and Escherichia coli.

Rat defensins were purified and tested for in vitro bactericidal assay against gram-positive and gram-negative bacteria. Staphylococcus aureus (209P, Cowan I, Smith diffuse and Smith compact) were resistant to defensins, whereas Staphylococcus epidermidis, Staphylococcus saprophyticus, Micrococcus lysodeikticus and Bacillus subtilis were less sensitive. Gram-negative bacteria, such as Pseudomonas aeruginosa (mucoid and K) and Klebsiella pneumoniae (Chedid, 277, and 8N3 which were heavily capsulated, moderately capsulated and noncapsulated, respectively) were all very sensitive to defensins and killed within 20 min. Escherichia coli was moderately sensitive and the rough mutants of lipopolysaccharide (LPS) of Salmonella typhimurium LT2, such as Ra, Rc, Rd, and Re were equally sensitive to defensins, being killed within 40 min. Lysozyme did not show any bactericidal activity except against M. lysodeikticus and B. subtilis, whereas it enhanced the bactericidal activity of defensins against P. aeruginosa, E. coli, and K. pneumoniae and suppressed the killing activity of defensins against S. typhimurium and S. aureus. With regard to the three synthetic rabbit defensins, NP1, NP4, and NP5, NP1 showed strong bactericidal activity against K. pneumoniae 277, comparable to that of rat defensins. Neither NP4 nor NP5 showed any bactericidal activity, while NP5 rather enhanced the bactericidal activity of NP1 against K. pneumoniae 277.

Animals↗

PubMed2005

Inhibitory effects of various micro-organisms on the growth of Helicobacter pylori.

AIMS: To examine the in vitro influence of various bacteria species on Helicobacter pylori (Hp) growth. METHODS AND RESULTS: The effects of 29 micro-organisms on 31 Hp strains were determined using two modified 'cross streak' methods. Staphylococcus epidermidis, Staphylococcus aureus, Pseudomonas aeruginosa, Stenotrophomonas maltophilia, Morganella morganii, Serratia marcescens, Bacteroides fragilis, Fusobacterium nucleatum and Clostridium difficile showed the strongest inhibition. The inhibitory effects varied, depending on the bacteria spp. and Hp strains, and were method dependent. The cagA status of Hp strains did not correlate with the extent of inhibition. CONCLUSIONS: Helicobacter pylori is inhibited by a significant number of commensal bacteria species as well as opportunistic human pathogens. The success and progress of Hp infection may be influenced by the bacterial flora present, while the difficulty in cultivating Hp from the oral mucosa and faeces may be the result of antagonistic bacterial interaction. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides valuable data on the sensitivity of Hp to a variety of intestinal and oral commensals as well as opportunistic human pathogens. Hp's varying pathogenicity and the specific localization of infection may be the result of these sensitivities. These results can also serve as a basis for further studies to identify the inhibitory substances and make them available for therapeutic use.

Antibiosis↗

PubMed2006

Lysis of staphylococcal mastitis pathogens by bacteriophage phi11 endolysin.

The Staphylococcus aureus bacteriophage phi11 endolysin has two peptidoglycan hydrolase domains (endopeptidase and amidase) and an SH3b cell wall-binding domain. In turbidity reduction assays, the purified protein can lyse untreated staphylococcal mastitis pathogens, Staphylococcus aureus and coagulase-negative staphylococci (Staphylococcus chronogenes, Staphylococcus epidermidis, Staphylococcus hyicus, Staphylococcus simulans, Staphylococcus warneri and Staphylococcus xylosus), making it a strong candidate protein antimicrobial. This lytic activity is maintained at the pH (6.7), and the "free" calcium concentration (3 mM) of milk. Truncated endolysin-derived proteins containing only the endopeptidase domain also lyse staphylococci in the absence of the SH3b-binding domain.

Animals↗

PubMed2005

Increase of faecal bifidobacteria due to dietary oligosaccharides induces a reduction of clinically relevant pathogen germs in the faeces of formula-fed preterm infants.

UNLABELLED: In a previous study on formula-fed preterm infants, we were able to demonstrate that dietary oligosaccharides (a mixture of 90% galacto-oligosaccharides and 10% fructo-oligosaccharides in a concentration of 1 g/dl) stimulate the growth of faecal bifidobacteria. In the present explorative analysis of this study, we focus on the effect of the dominance of bifidobacteria on the presence of clinically relevant pathogens (Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus haemolyticus, Pseudomonas aeruginosa, Enterobacter, Klebsiella, Proteus, Streptococcus group B, Clostridium difficile, Bacillus subtilis and Acinetobacter). CONCLUSION: The data demonstrate that stimulation of bifidobacteria by prebiotic oligosaccharides reduces the presence of clinically relevant pathogens in the faecal flora, indicating that prebiotic substances might have the capacity to protect against enteral infections.

Bacterial Infections↗

PubMed1988

Molecular cloning and genetic analysis of a chloramphenicol acetyltransferase determinant from Clostridium difficile.

A gene bank from a clinical isolate of Clostridium difficile expressing high chloramphenicol acetyltransferase activity was constructed by cloning Sau3A-cleaved clostridial DNA fragments into the plasmid vector pUC13. Among 1,020 clones tested, 11 were resistant to chloramphenicol; 1 of these, with an insert size of 1.9 kilobases (pPPM9), was studied further. The clone pPPM9 was mapped using a variety of restriction enzymes, and a 0.27-kilobase EcoRV-TaqI restriction fragment was shown to be within the chloramphenicol resistance (Cmr) gene by using transposon (Tn1000) mutagenesis. The 0.27-kilobase fragment and the 1.9-kilobase insert were radiolabeled and used as DNA probes in hybridization studies. Southern blot analysis with the gene probes against chromosomal DNA from Cmr strains of C. difficile obtained from five distinct geographical locations revealed that at least two copies of the same chloramphenicol acetyltransferase gene were present for each strain. Hybridization of the gene probes against Cmr strains of Staphylococcus epidermidis, Staphylococcus aureus, Klebsiella edwardsii, Escherichia coli, and to four other clostridial species revealed no homology even under conditions of low stringency.

Blotting, Southern↗

PubMed1995

Antimicrobial activity of CS-940, a new trifluorinated quinolone.

The antimicrobial activity of CS-940, a new trifluorinated quinolone drug, was tested against 761 clinical isolates. CS-940 activity against members of the family Enterobacteriaceae was most similar to that of ciprofloxacin and ofloxacin, with a large range of MICs inhibiting 90% of isolates tested (MIC90S) of 0.015 to 16 micrograms/ml (median MIC90, 0.06 micrograms/ml). CS-940 had greater activity than ciprofloxacin or ofloxacin when they were tested against Acinetobacter spp. (MIC90S, 0.03 micrograms/ml) and Stenotrophomonas (Xanthomonas) maltophilia (MIC90S, 2 micrograms/ml). CS-940 demonstrated a high degree of potency against Haemophilus influenzae, Moraxella catarrhalis, and Neisseria spp. (MIC90S, < or = 0.06 micrograms/ml). CS-940 was two- to eightfold more active than ciprofloxacin or ofloxacin against oxacillin-susceptible Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus haemolyticus, and coagulase-negative Staphylococcus spp. CS-940 was also very active against Streptococcus spp. and enterococci, for which MIC90S were < or = 2 micrograms/ml; for Enterococcus faecium, however, the MIC90 was 4 micrograms/ml. CS-940 was generally less active than a comparison investigational fluoroquinolone, clinafloxacin. This compound appears promising by in vitro test analysis and warrants further in vivo trials.

Anti-Infective Agents↗

PubMed1998

Activities of LL-37, a cathelin-associated antimicrobial peptide of human neutrophils.

Human neutrophils contain two structurally distinct types of antimicrobial peptides, beta-sheet defensins (HNP-1 to HNP-4) and the alpha-helical peptide LL-37. We used radial diffusion assays and an improved National Committee for Clinical Laboratory Standards-type broth microdilution assay to compare the antimicrobial properties of LL-37, HNP-1, and protegrin (PG-1). Although generally less potent than PG-1, LL-37 showed considerable activity (MIC, <10 microgram/ml) against Pseudomonas aeruginosa, Salmonella typhimurium, Escherichia coli, Listeria monocytogenes, Staphylococcus epidermidis, Staphylococcus aureus, and vancomycin-resistant enterococci, even in media that contained 100 mM NaCl. Certain organisms (methicillin-resistant S. aureus, Proteus mirabilis, and Candida albicans) were resistant to LL-37 in media that contained 100 mM NaCl but were susceptible in low-salt media. Burkholderia cepacia was resistant to LL-37, PG-1, and HNP-1 in low- or high-salt media. LL-37 caused outer and inner membrane permeabilization of E. coli ML-35p. Chromogenic Limulus assays revealed that LL-37 bound to E. coli O111:B4 lipopolysaccharide (LPS) with a high affinity and that this binding showed positive cooperativity (Hill coefficient = 2.02). Circular dichroism spectrometry disclosed that LL-37 underwent conformational change in the presence of lipid A, transitioning from a random coil to an alpha-helical structure. The broad-spectrum antimicrobial properties of LL-37, its presence in neutrophils, and its inducibility in keratinocytes all suggest that this peptide and its precursor (hCAP-18) may protect skin and other tissues from bacterial intrusions and LPS-induced toxicity. The potent activity of LL-37 against P. aeruginosa, including mucoid and antibiotic-resistant strains, suggests that it or related molecules might have utility as topical bronchopulmonary microbicides in cystic fibrosis.

Amino Acid Sequence↗

PubMed2004

Peritoneal fluid titer test for peritoneal dialysis-related peritonitis.

Standard microbiological tests (i.e., MIC) do not account for the unique factors of peritoneal dialysis (PD)-related peritonitis which can significantly influence treatment response. Our goals were to develop a peritoneal fluid titer (PFT) test and to conduct a pilot study of its association with clinical outcome. The methodology was developed by using spent dialysate collected from patients with bacterial PD-related peritonitis prior to the initiation of antibiotics. Dialysate was processed and spiked with antibiotic to simulate two standard intraperitoneal regimens: cefazolin plus tobramycin and cefazolin alone. Thirty-six clinical isolates, including Staphylococcus epidermidis, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, and Pseudomonas aeruginosa, were tested. In the pilot study, dialysate was collected from 14 patients with bacterial PD-related peritonitis. Titers were determined by using each patient's dialysate and infecting pathogen. Titers were highly reproducible, with discrepancies in only 1% of cases. Overall, PFTs were notably higher against gram-positive bacteria (P < 0.0001). The addition of tobramycin increased titers significantly from zero to values of 1/16 to 1/64 against E. cloacae and P. aeruginosa (P < 0.0001). In the pilot study, peritoneal fluid inhibitory titers were significantly associated with clinical outcome, with a median value of 1/96 for patients who were cured compared to 1/32 for those who failed treatment (P = 0.036). In conclusion, this study provides preliminary support for the PFT as a pharmacodynamic index specific to the treatment of PD-related peritonitis. With further characterization and validation in patients, the PFT test may advance the study of antibiotic therapies for PD-related peritonitis.

Aged↗

PubMed1978

Interactions of Bacillus licheniformis ATCC 10716 and normal flora of human skin.

To determine whether antibiotic production might be ecologically advantageous in the survival of Bacillus species on human skin, we applied spores of a bacitracin-producing strain of Bacillus licheniformis (ATCC 10716) to the forearms of 11 volunteers. Three additional strains of B. licheniformis which did not synthesize antibiotics, including a mutant of ATCC 10716, were used in subsequent control trials. Samples of flora were taken from inoculated and control (opposite forearm) sites during the colonization period, generally 3 weeks. Although population densities were unaltered, changes in the carriage, composition, and bacitracin sensitivity of resident flora were related with the presence of ATCC 10716 only, which suggests that microbial interactions are important in bacillus colonization and in maintenance of normal flora. Interactions were examined in vitro by comparing growth curves of representative skin bacteria, including isolates of Staphylococcus epidermidis, Staphylococcus saprophyticus, Micrococcus luteus, and a large-colony diphtheroid, grown individually, in mixed culture with each other, and together in presence of each test strain of B. licheniformis. We observed some diminution of growth of M. luteus and the diphtheroid in the first mixed culture, and the diphtheroid was completely retarded in common culture with ATCC 10716. Lesser antibiotic effects were seen on the cocci, whose rank of sensitivity was similar to that in vivo. The growth of the diphtheroid was enhanced in mixed culture with those strains of bacilli which lack antibiotic activity.

Adult↗

PubMed1993

Quantitative and Qualitative Analysis of Bacteria in Er(III) Solution by Thin-Film Magnetopheresis.

Magnetic deposition, quantitation, and identification of bacteria reacting with the paramagnetic trivalent lanthanide ion, Er, was evaluated. The magnetic deposition method was dubbed thin-film magnetopheresis. The optimization of the magnetic deposition protocol was accomplished with Escherichia coli as a model organism in 150 mM NaCl and 5 mM ErCl(3) solution. Three gram-positive bacteria, Staphylococcus epidermidis, Staphylococcus saprophyticus, and Enterococcus faecalis, and four gram-negative bacteria, E. coli, Pseudomonas aeruginosa, Proteus mirabilis, and Klebsiella pneumoniae, were subsequently investigated. Quantitative analysis consisted of the microscopic cell count and a scattered-light scanning of the magnetically deposited material aided by the computer data acquisition system. Qualitative analysis consisted of Gram stain differentiation and fluorescein isothiocyanate staining in combination with selected antisera against specific types of bacteria on the solid substrate. The magnetic deposition protocol allowed quantitative detection of E. coli down to the concentration of 10 CFU ml, significant in clinical diagnosis applications such as urinary tract infections. Er did not interfere with the typical appearance of the Gram-stained bacteria nor with the antigen recognition by the antibody in the immunohistological evaluations. Indirect antiserum-fluorescein isothiocyanate labelling correctly revealed the presence of E. faecalis and P. aeruginosa in the magnetically deposited material obtained from the mixture of these two bacterial species. On average, the reaction of gram-positive organisms was significantly stronger to the magnetic field in the presence of Er than the reaction of gram-negative organisms. The thin-film magnetophoresis offers promise as a rapid method for quantitative and qualitative analysis of bacteria in solutions such as urine or environmental water.

Journal Article↗

PubMed2005

Surface microflora of four smear-ripened cheeses.

The microbial composition of smear-ripened cheeses is not very clear. A total of 194 bacterial isolates and 187 yeast isolates from the surfaces of four Irish farmhouse smear-ripened cheeses were identified at the midpoint of ripening using pulsed-field gel electrophoresis (PFGE), repetitive sequence-based PCR, and 16S rRNA gene sequencing for identifying and typing the bacteria and Fourier transform infrared spectroscopy and mitochondrial DNA restriction fragment length polymorphism (mtDNA RFLP) analysis for identifying and typing the yeast. The yeast microflora was very uniform, and Debaryomyces hansenii was the dominant species in the four cheeses. Yarrowia lipolytica was also isolated in low numbers from one cheese. The bacteria were highly diverse, and 14 different species, Corynebacterium casei, Corynebacterium variabile, Arthrobacter arilaitensis, Arthrobacter sp., Microbacterium gubbeenense, Agrococcus sp. nov., Brevibacterium linens, Staphylococcus epidermidis, Staphylococcus equorum, Staphylococcus saprophyticus, Micrococcus luteus, Halomonas venusta, Vibrio sp., and Bacillus sp., were identified on the four cheeses. Each cheese had a more or less unique microflora with four to nine species on its surface. However, two bacteria, C. casei and A. arilaitensis, were found on each cheese. Diversity at the strain level was also observed, based on the different PFGE patterns and mtDNA RFLP profiles of the dominant bacterial and yeast species. None of the ripening cultures deliberately inoculated onto the surface were reisolated from the cheeses. This study confirms the importance of the adventitious, resident microflora in the ripening of smear cheeses.

Bacteria↗

PubMed1984

Expression of the gene encoding protein A in Staphylococcus aureus and coagulase-negative staphylococci.

Two shuttle vectors containing the gene for protein A (spa) from Staphylococcus aureus have been constructed to study expression of the gene in various strains of S. aureus and in the coagulase-negative species Staphylococcus epidermidis, Staphylococcus capitis, and Staphylococcus xylosus. One plasmid, pSPA15, contains the complete structural gene for protein A, which binds to the cell wall in various Staphylococcus species. The other plasmid, pSPA16, codes for a truncated protein A lacking the C-terminal part called region X. The latter is exclusively extracellular in all Staphylococcus species tested, which confirms the importance of region X for cell wall binding. The expression of the plasmid-coded protein A in various strains of S. aureus is strongly correlated to the expression of the chromosomal spa gene. The coagulase-negative species expressing plasmid-encoded protein A produce 12 to 30% of the amount coded by the chromosomal spa gene in S. aureus strains Cowan I and A676.

Amino Acid Sequence↗

PubMed1982

Detection of fungemia obscured by concomitant bacteremia: in vitro and in vivo studies.

Our recent clinical experience suggested that bacteremia may interfere with the detection of concomitant fungemia when standard blood culture methods are used. To determine the extent to which bacteria may interfere with fungal isolation from blood cultures, an in vitro model simulating blood cultures taken during concomitant fungemia and bacteremia was created. Each of six bacteria (Staphylococcus epidermidis, Staphylococcus aureus, Streptococcus faecalis, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa) was combined with each of three pathogenic yeasts (Candida albicans, Candida tropicalis, and Torulopsis glabrata) in vented blood culture bottles containing enriched brain heart infusion broth and fresh normal human blood. Blood culture bottles were analyzed at 1, 2, and 7 days of incubation. Gram strains and subcultures onto chocolate and MacConkey agars failed to detect fungi in 37.0, 66.7, and 100% of samples, respectively. However, subcultures onto Sabouraud dextrose agar failed in only 13% of the samples (occurring only with P. aeruginosa). In a rabbit model of concomitant fungemia with C. albicans and bacteremia with P. aeruginosa, no yeasts were recovered from blood cultures despite 100% detection of P. aeruginosa. Therefore, the usual microbiological techniques may be inadequate to detect fungemia when concomitant bacteremia is present.

Animals↗

PubMed1984

Chocolate agar, a differential medium for gram-positive cocci.

Reactions incurred on chocolate agar by gram-positive cocci were correlated with species identity. Darkening and clearing of the medium was usually associated with the species Staphylococcus epidermidis, Staphylococcus aureus, Staphylococcus simulans, and Streptococcus faecalis. Yellowing of chocolate agar was associated with alpha-hemolytic species of Streptococcus. The study demonstrated that reactions occurring on chocolate agar are useful in identifying gram-positive cocci.

Agar↗

PubMed1987

Synergistic hemolysis associated with coagulase-negative staphylococci isolated from bovine mammary glands.

A total of 353 coagulase-negative staphylococcus (CNS) isolates from infected bovine mammary glands were tested for cytolysin production by using the synergistic hemolysin assay (SHA). Overall, 34.6% of CNS isolates were SHA positive. Human-associated, coagulase-negative staphylococcal species contained the greatest number of SHA-positive strains. Milk leukocyte levels expressed as somatic cell counts (SCC) were elevated with SHA-positive Staphylococcus epidermidis, Staphylococcus hominis, and Staphylococcus warneri strains. Elevated SCC levels were associated with strains of Staphylococcus hyicus and Staphylococcus chromogenes. However, no difference in SCC levels was observed between SHA-positive and SHA-negative strains. Results indicated that the SHA was a sensitive test for the detection of cytolysin-producing CNS.

Animals↗

PubMed1991

Identification of methicillin-resistant strains of staphylococci by polymerase chain reaction.

A simple and reliable method using a polymerase chain reaction (PCR) was devised to identify methicillin-resistant staphylococci. By using lysates of the strain to be tested as templates and 22-mer oligonucleotides as primers, a 533-bp region of mecA, the structural gene of a low-affinity penicillin-binding protein (PBP 2'), was amplified by PCR and detected by agarose gel electrophoresis. Results obtained by this method were compared with those obtained by broth microdilution MIC determination for 210 and 100 clinical isolates of Staphylococcus aureus and coagulase-negative staphylococci, respectively. Of 99 mecA-negative S. aureus isolates, 100% of the strains were methicillin susceptible and 98% of the strains were oxacillin susceptible. Three strains (3%) of 111 mecA-positive S. aureus isolates exhibited almost the same susceptibility to beta-lactams as the mecA-negative ones and did not produce detectable amounts of PBP 2' despite the presence of the mecA gene. One of them yielded typically methicillin-resistant variants at a low frequency with concomitant recovery of PBP 2' production. The mecA gene was also found in coagulase-negative Staphylococcus epidermidis, Staphylococcus haemolyticus, Staphylococcus sciuri, Staphylococcus saprophyticus, and Staphylococcus caprae and conferred resistance on most of the bacteria.

Bacterial Proteins↗

PubMed1991

Occurrence of Staphylococcus lugdunensis in consecutive clinical cultures and relationship of isolation to infection.

Consecutive record review over a 63-month period revealed 229 Staphylococcus lugdunensis isolates, or 10.1% of the staphylococcal species that were not Staphylococcus aureus or Staphylococcus epidermidis. A total of 155 S. lugdunensis specimens were isolated from sites over the entire bodies of the 143 patients studied. The most common clinical diagnoses were skin and skin structure infections (55.4%) and blood and vascular catheter infections (17.4%). For 40% of the reviewed specimens, S. lugdunensis was the sole agent isolated, and for 60% of specimens, S. lugdunensis was isolated as part of mixed flora. In only 15.4% of clinically reviewed specimens was S. lugdunensis clearly a culture contaminant or colonizing organism. The pattern of human infection identified in this study emphasizes the predominance of skin and soft tissue S. lugdunensis infections over deep serious infections such as endocarditis, peritonitis, infected hip prosthesis, and osteomyelitis and vascular-associated infections. S. lugdunensis should be included along with S. epidermidis, Staphylococcus haemolyticus, and Staphylococcus saprophyticus as a coagulase-negative species of Staphylococcus pathogenic for humans.

Adolescent↗

PubMed2000

Glyceraldehyde-3-phosphate dehydrogenase-encoding gene as a useful taxonomic tool for Staphylococcus spp.

The gap gene of Staphylococcus aureus, encoding glyceraldehyde-3-phosphate dehydrogenase, was used as a target to amplify a 933-bp DNA fragment by PCR with a pair of primers 26 and 25 nucleotides in length. PCR products, detected by agarose gel electrophoresis, were also amplified from 12 Staphylococcus spp. analyzed previously. Hybridization with an internal 279-bp DNA fragment probe was positive in all PCR-positive samples. No PCR products were amplified when other gram-positive and gram-negative bacterial genera were analyzed using the same pair of primers. AluI digestion of PCR-generated products gave 12 different restriction fragment length polymorphism (RFLP) patterns, one for each species analyzed. However, we could detect two intraspecies RFLP patterns in Staphylococcus epidermidis, Staphylococcus hominis, and Staphylococcus simulans which were different from the other species. An identical RFLP pattern was observed for 112 S. aureus isolates from humans, cows, and sheep. The sensitivity of the PCR assays was very high, with a detection limit for S. aureus cells of 20 CFU when cells were suspended in saline. PCR amplification of the gap gene has the potential for rapid identification of at least 12 species belonging to the genus Staphylococcus, as it is highly specific.

Glyceraldehyde-3-Phosphate Dehydrogenases↗