PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Staphylococcus aureus”

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 379 records · Page 21Linked to original sources
PubMed2004

Antimicrobial spectrum, production and mode of action of staphylococcin 188 produced by Staphylococcus aureus 188.

Staphylococcus aureus 188 has been shown to produce bacteriocin-like inhibitory substance known as staphylococcin 188. It has a broad-activity spectrum against Micrococcus luteus, Streptococcus pneumoniae, Streptococcus faecalis, Streptococcus viridans, Corynebacterium diphtheriae and several staphylococcus species. The arbitrary unit of staphylococcin 188 against Micrococcus luteus was 1280 AU/mL. Its production with simultaneous measurement of activity was monitored and was found to produce maximum amount of staphylococcin after 7 hours of incubation. Mode of action of the staphylococcin 188 on the sensitive cells was bactericidal rather than bacterioloytic.

Journal Article↗
PubMed2004

Bloodstream infections caused by Staphylococcus aureus in a university hospital in Turkey: clinical and molecular epidemiology of methicillin-resistant Staphylococcus aureus.

In total, 177 patients with bloodstream infections caused by Staphylococcus aureus (BSISA) were investigated prospectively between June 1999 and June 2001. Of these, 19.8% had community-acquired BSISA, while 80.2% had nosocomial BSISA. Surgical intervention, foreign body, mechanical ventilation, total parenteral nutrition, and previous antibiotic treatment were found to be important risk factors for the nosocomial BSISA group. Secondary BSISA formed a greater proportion (62.9%) of community-acquired infections than of nosocomial infections (26.8%; p 0.0001). Catheter-related nosocomial BSISA was observed in 72.1% of patients. The suppurative complication rate was significantly higher among community-acquired infections (22.9%) than among nosocomial infections (6.3%; p 0.008). Of the nosocomial BSISA, 65.5% were methicillin-resistant. Analysis of 80 methicillin-resistant S. aureus isolates by pulsed-field gel electrophoresis identified ten main clones (A-J), but 61 (76.3%) of the 80 isolates belonged to clone A.

Adult↗
PubMed1969

Exopenicillinase synthesis in Staphylococcus aureus.

In Staphylococcus aureus, penicillinase remaining cell-bound (60 to 75% of original total) after treatment with citrate does not become exopenicillinase. Exopenicillinase in these cells appears only under conditions permitting de novo penicillinase synthesis. By use of (14)C-labeled cells, it was shown that exopenicillinase consists of newly synthesized molecules which have not equilibrated with preformed membrane-bound enzyme.

Amino Acids↗
PubMed1970

Lysostaphin-induced, osmotically fragile Staphylococcus aureus cells.

Staphylococcus aureus FDA 209P cells when suspended in 24% (w/v) NaCl were rendered osmotically fragile by exposure to lysostaphin for time intervals ranging from 2 to 60 min. Such cells were analyzed chemically and serologically for evidence of residual cell wall material, were plated in hypertonic sucrose medium to determine revertibility to normal, and were subjected to manometric studies to determine metabolic capabilities. Most of the cells (95%) which were exposed to lysostaphin (0.5 or 1.0 unit/ml) for 2 min, although osmotically fragile, retained their cell wall hexosamine and were capable of reverting to osmotically normal cells when plated in hypertonic medium. Cells exposed to lysostaphin for 5 and 10 min also retained much of their cell wall hexosamine, but lost their ability to revert to normal staphylococci. Cells exposed to lysostaphin for 2 to 10 min continued to react with staphylococcus anti-k antiserum. Complete removal of cell wall hexosamine was attained only after exposure to lysostaphin for 20 min or more; these cells failed to react with k antiserum. Lysostaphin-induced L-type colonies were extremely rare in our experiments, even if incubation times and media were optimal for their detection. Lysostaphin-induced staphylococcal protoplasts were as active metabolically in manometric studies as were untreated staphylococci.

Agar↗
PubMed1969

Formation of vitamin K2 isoprenologues by Staphylococcus aureus.

In Staphylococcus aureus, vitamin K(2) isoprenologues can be labeled with (14)C-acetate, mevalonate, glycerol, alpha-naphthol, and menadione. All the radioactivity from alpha-naphthol is in the ring nucleus. Eighty-six per cent of the radioactivity from mevalonate is in the side chain. The labeled isoprenologues of vitamin K(2) can be separated and recovered quantitatively. The rates of incorporation and turnover after pulse-chase experiments indicate that the isoprenologues do not lose radioactivity once they are formed. The kinetics of incorporation of radioactivity into the ring nucleus of each isoprenologue are the same. The alkylation of the ring does not involve a simple sequential addition of isoprenoid units of the same specific activity. The incorporation of mevalonate shows that shorter side chain isoprenologues have a higher specific activity per five carbon unit than the longer side chain isoprenologues. Perhaps the alkyl precursors are from different pools since the kinetics of incorporation into all isoprenologues are different.

Carbon Isotopes↗
PubMedDate not supplied

Human mononuclear cell chemiluminescence and interleukin-1 release induced by Staphylococcus aureus protein A.

Staphylococcus aureus protein A (SpA) is shown to induce a temporary chemiluminescence (CL)-response of human peripheral blood mononuclear cells. Maximal activity of SpA is observed at 3 micrograms/ml and EC50 is about 1 microgram/ml. The CL response depends on extracellular calcium, and moreover is inhibited by pretreating cells with rabbit-anti-human IgG's. From glass-adhered monocytes, SpA alone (3 micrograms/ml) did not consistently affect the generation of immunoreactive interleukin-1 (IL-1). However, SpA and endotoxin (1 micrograms/ml) showed a marked synergistic effect on IL-1 release. The results suggest that SpA interacts with membrane-bound Ig molecules endowed with receptor functions. The CL response may be envisaged as a result of early transmembrane signalling events presumably taking place in monocytes. Apparently, hereby, the cells become primed for endotoxin-triggered IL-1 release.

Endotoxins↗
PubMed1990

Repeated echocardiography: essential in the management of Staphylococcus aureus endocarditis.

Staphylococcus aureus endocarditis in a previously healthy 25 year old man is described. Repeated echocardiography recorded rapid progression of aortic root and interventricular septal involvement and, even though the patient was clinically stable, early surgery was advised with a satisfactory outcome. This case report clearly demonstrates the vital role of repeated cross-sectional echocardiography in the management of such cases.

Adult↗
PubMed1990

Normal leukocyte counts in Staphylococcus aureus septicaemia.

Staphylococcus aureus septicaemia is still a serious disease with a high mortality. The absence of leukocytosis in serious bacterial infections is generally considered as an unfavourable prognostic sign. The leukocyte pattern in 75 patients with S. aureus septicaemia was reviewed retrospectively. In the 66 patients where leukocyte determinations were done within 2 days of positive blood culture, 21 presented without leukocytosis which contrasts to only 1/35 patients with Escherichia coli septicaemia studied as controls (p less than 0.001). During follow up of S. aureus septicaemia only 5 of the patients developed leukocytosis greater than 10 x 10(9)/l and 2 leukopenia. There was no significant difference in mortality in patients without initial leukocytosis (14%) compared to patients with initial leukocytosis (24%). Except for septic arthritis, which was associated significantly more often with leukocytosis, complications were found with about the same frequency in both groups. Thus absence of leukocytosis seems not be an unfavourable prognostic sign in S. aureus septicaemia.

Adult↗
PubMed1983

Vancomycin treatment of bacteremia caused by oxacillin-resistant Staphylococcus aureus: comparison with beta-lactam antibiotic treatment of bacteremia caused by oxacillin-sensitive Staphylococcus aureus.

The epidemiology and therapy of 29 episodes of bacteremia caused by oxacillin- and aminoglycoside-resistant Staphylococcus aureus (OARSA) were compared with 29 episodes of bacteremia due to oxacillin-sensitive S. aureus (OSSA) that occurred during a 36-month period. Patients with bacteremia due to OSSA were younger (P less than 0.05) and were admitted more frequently with acute traumatic injury (P less than 0.01). The overall survival rate one month after persistent bacteremia was 74% for patients with OARSA bacteremia treated with vancomycin compared with 70% for patients with OSSA bacteremia treated with a beta-lactam antibiotic. The results indicate that vancomycin is an effective antibiotic for the treatment of bacteremia caused by OARSA and suggest that its effectiveness is comparable to that of beta-lactam antibiotic treatment of bacteremia due to OSSA.

Anti-Bacterial Agents↗
PubMed2004

Staphylococcus aureus, but not Staphylococcus epidermidis, modulates the oxidative response and induces apoptosis in human neutrophils.

S. epidermidis is the most common isolate in foreign body infections. The aim of this study was to understand why S. epidermidis causes silent biomaterial infections. In view of the divergent inflammatory responses S. epidermidis and S. aureus cause in patients, we analyzed how they differ when interacting with human neutrophils. Neutrophils interacting with S. epidermidis strains isolated either from granulation tissue covering infected hip prostheses or from normal skin flora were tested by measuring the oxidative response as chemiluminescence and apoptosis as annexin V binding. Different S. aureus strains were tested in parallel. All S. epidermidis tested were unable to modulate the oxidative reaction in response to formyl-methionyl-leucyl-phenylalanine (fMLP) and did not provoke, but rather inhibited, apoptosis. In contrast, some S. aureus strains enhanced the oxidative reaction, and this priming capacity was linked to p38-mitogen-activated-protein-kinase (p38-MAPK) activation and induction of apoptosis. Our results may explain why S. epidermidis is a weak inducer of inflammation compared to S. aureus, and therefore responsible for the indolent and chronic course of S. epidermidis biomaterial infections.

Annexin A5↗
PubMed1992

[The beta-lactamase activity in methicillin-resistant Staphylococcus aureus--a comparison of the beta-lactamase from a methicillin-resistant and from a methicillin-sensitive strain of Staphylococcus aureus].

Strains of Methicillin-resistant Staphylococcus aureus (MRSA) are more frequently beta-lactamase-negative than those of Methicillin-susceptible S. aureus (MSSA). In the strains of MRSA, the beta-lactamase activity tends to be inversely related to the MIC's of Methicillin. Such a marked tendency has been observed in recent years.

Methicillin↗