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S Stepanović

Publications and source records attributed to S Stepanović.

9 recordsLinked to original sources
PubMed2001

Staphylococcus sciuri as a part of skin, nasal and oral flora in healthy dogs.

The coagulase-negative species Staphylococcus sciuri is widespread in nature and is associated with a variety of domestic and wild animals. However, the occurrence of S. sciuri in dogs has received little attention so far. In the present study, we established the prevalence of S. sciuri in a large population of healthy dogs, and characterized isolated strains. Samples from two mucous membrane sites (anterior nares and mouth), and two hair-coated sites (head and withers) were taken from 122 dogs and inoculated into STS agar, a novel selective medium that was introduced and tested in the study. In total, 116 isolates of S. sciuri were obtained from 488 specimens. S. sciuri was isolated from 56 out of 122 (46%) dogs. The occurrence of S. sciuri in the anterior nares and mouth were significantly higher than those in withers and head. No significant association of S. sciuri occurrence in dogs and factors such as sex, age, and living environment (indoor/outdoor) was found. Out of 56 dogs, which tested positive for S. sciuri, 30 (54%) would have it as a resident flora. Thus, we showed that S. sciuri was frequently present as a part of skin, nasal and oral flora in healthy dogs both as a resident and transient carriage.

Animals↗
PubMed2001

Possible virulence factors of Staphylococcus sciuri.

Staphylococcus sciuri is an opportunistic pathogen of controversial clinical significance. The factors that contribute to colonization and/or infection caused by this bacterium have not been studied intensively so far. The present research was carried out in order to study the presence of potential virulence factors in 121 human and animal isolates of this bacterium. Isolates were examined for biofilm formation, hemagglutination, presence of clumping factor, production of spreading factors and exotoxins, cytotoxicity and capacity to stimulate nitric oxide production. The results showed that S. sciuri is highly capable of biofilm production, that it displays strong proteolytic and DNase activities, produces hemolysins and stimulates nitric oxide production by rat macrophages. Although the present study showed existence of a wide spectrum of possible virulence determinants of S. sciuri, their exact contribution to virulence of this bacterium in vivo remains to be determined.

Animals↗
PubMed2001

Influence of dynamic conditions on biofilm formation by staphylococci.

The modified microtiter plate test was used to investigate biofilm formation by staphylococci under both static and dynamic conditions. The quantity of biofilm produced under static conditions was used as a reference. Dynamic conditions, which were achieved by incubating microtiter plates on a horizontal shaker with and without the presence of glass beads in wells, either reduced biofilm formation or left it unchanged. Dynamic conditions particularly affected the capacity of certain species to produce biofilm: these species included the causative agents of infections associated with a foreign body (Staphylococcus epidermidis, Staphylococcus aureus). On the basis of these results, dynamic conditions should be included as a parameter for evaluating biofilm formation by staphylococci in vitro.

Biofilms↗
PubMed2000

Staphylococcus sciuri: recommendation for simple identification.

We report the isolation of Staphylococcus sciuri, primarily animal species, from samples taken from hospitalised patients. Considering that Staphylococcus sciuri often remains unrecognised in routine laboratory practice, we propose the criteria for simple identification of this bacterium.

Bacterial Typing Techniques↗
PubMed1998

Ground red hot pepper agar in the isolation of yeasts of Candida spp.

The purpose of this study was to investigate and determine the value of a novel, simple and inexpensive selective medium for isolation of yeasts of Candida spp. - ground red hot pepper agar (GRHP). The study compared GRHP and Sabouraud dextrose agar (SDA), an insufficiently selective medium routinely used for primary isolation of yeasts. The comparison was based on qualitative and quantitative characterisation of growth of 25 bacterial strains, measurement of growth of 22 yeast strains and testing on clinical specimens. Qualitative tests on bacteria showed either significantly less growth on GRHP than on SDA, or no growth on GRHP. Quantitative tests confirmed these results; the number of colonies of all tested bacterial species and strains on GRHP was significantly lower than on SDA. With regard to the isolation of Candida spp., GRHP had the same properties as SDA. Statistical analysis showed no significant differences in the growth of Candida spp. and strains on the two media. All these results were confirmed by tests on clinical material. The results clearly show that GRHP agar is an economical medium for the isolation of yeasts of Candida spp., with excellent selectivity.

Bacteria↗
PubMed1995

Myocardial catecholamines in primary heart muscle disease: fact or fancy?

The pathophysiological role of myocardial catecholamines in cardiomyopathies is still not completely understood. We there-fore assessed myocardial catecholamine concentrations (MCC) in 34 patients with hypertrophic cardiomyopathy (HCM) (76.5% males; mean age 46.7 +/- 11.6 years; left ventricular ejection fraction [LVEF] 75.3 +/- 9.8%) and in 32 patients with dilated cardiomyopathy (DCM) (87.5% males, mean age 43.1 +/- 12.5 years, LVEF 34.9 +/- 8.3%). Initial assessment included clinical work up, cardiac catheterization and endomyocardial biopsy. Myocardial norepinephrine (MNEC), epinephrine (MEC), and dopamine (MDC) concentrations in endomyocardial biopsy samples were measured using the catechol-O- methyl transferase radioenzymatic method. Significantly higher MNEC and MEC were demonstrated in HCM than in DCM patients (MNEC: 781.9 +/- 125.8 ng.g-1 fresh myocardial tissue (ft) HCM vs 262.6 +/- 68.9 ng.g-1 ft DCM, p < 0.01; and MEC: 91.6 +/- 13.9 ng.g-1 ft HCM vs 35.8 +/- 6.2 ng.g-1 ft DCM, P < 0.01). The difference in MDC did not reach statistical significance (76.1 +/- 8.3 ng.g-1 ft HCM vs 70.1 +/- 11.8 ng.g ft DCM; P > 0.05). In addition, we compared the MCC levels in 24 patients, clinically presented as dilated cardiomyopathy categorized according to the various aetiologies: 12/24 with primary DCM (75.0% males, mean age 49.6 +/- 9.5 years; LVEF 25.8 +/- 63%), 7/24 with alcohol-induced heart disease (85.7% males, mean age 46.8 +/- 7.1 years; LVEF 26.4 +/- 4.6%), and 5/24 with hypertensive heart disease (100% males, 45.1 +/- 10.6 years; LVEF 25.6 +/- 9.1%), but no significant difference was found among them (P > 0.05). There was no significant difference in tissue dopamine concentrations.

Adult↗
PubMed1992

Circulating inhibitor of interleukin 1 activity in patients with chronic renal diseases.

The effects of sera derived from patients suffering from chronic renal diseases (endemic Balkan nephropathy, glomerulonephritis and pyelonephritis) on T cell proliferative response was studied. It was found that these sera contained factors which affect interleukin 1 (IL-1) dependent events in T cell proliferative response. The factors prevent costimulatory effects of IL-1 on T cells but do not bind to IL-1, nor do they affect interleukin 2 (IL-2) dependent T cell proliferation. These findings indicate that immuno-suppression observed in some kidney disorders may be partially due to serum immunoinhibitory factors affecting IL-1 activity.

Adult↗