Search results for "Staphylococcal infections"

Phenotypic and genotypic evaluation of slime production by conventional and molecular microbiological techniques.

2009

Twenty-nine staphylococcal isolates from different clinical samples were tested for slime production: phenotypic characterization was carried out using Christensen test (tube test) and Congo red agar plate test (CRA plate test), while the presence and expression of icaA and icaD genes were evaluated by real-time PCR. In 79.3% of studied strains there was a concordance between slime production and presence of icaA and icaD genes, and between lack of slime production and absence of both or only one of the tested genes. In four of five strains where positive phenotype was not associated with the presence of ica genes, gene co-expression (evaluated by mRNA determination) was lacking, while in o…

Dispersal of methicillin resistant Staphylococcus aureus (MRSA) in a burn intensive care unit.

2003

Methicillin resistant Staphylococcus aureus (MRSA) is a pathogen of special concern in intensive care units (ICUs). The burn units are a very susceptible habitat to colonization and infection events by this organism. In this paper isolation of MRSA from a sepsis case and from samples of the care unit air is described, along with simultaneous circulation of two clones of MRSA. Some peculiar epidemiological features of MRSA in burn intensive care wards are confirmed.

Characterization of a Catalase-Negative Methicillin-Resistant Staphylococcus aureus Strain

2007

ABSTRACT We describe an unusual clinical strain of catalase-negative methicillin-resistant Staphylococcus aureus sensu stricto. Sequence analysis of its catalase gene showed 99.60% identities to the catalase genes of the reference strains. A 5-base deletion, however, led to a shift of the nucleotide reading frame and a loss of the enzymatic activity.

dltA overexpression: A strain-independent keystone of daptomycin resistance in methicillin-resistant Staphylococcus aureus

2013

The mechanisms leading to reduced susceptibility to daptomycin (DAP) are multifactorial and have not been fully elucidated. We analysed, by sequencing and expression studies, the role of the major molecular targets (cell-envelope charge genes, dltA, mprF, cls2; cell-wall turnover and autolysis genes, sceD, atl) involved in the emergence of DAP resistance in three series of isogenic clinical methicillin-resistant Staphylococcus aureus (MRSA) in which DAP resistance emerged after a heterogeneous glycopeptide-intermediate S. aureus (hGISA) step under teicoplanin and DAP therapy. All of the isolates had different genotypes and were delta-haemolysin negative, reflecting a strain proclivity to ac…

Methicillin-resistant Staphylococcus pseudintermedius as causative agent of dairy cow mastitis.

2013

Staphylococcus pseudintermedius is a coagulase-positive specie similar to Staphylococcus intermedius , frequently associated with pyoderma, otitis and urinary tract infections of dogs and cats (van Duijkeren and others 2011). No information about bovine mastitis caused by S pseudintermedius is available in the literature. Antimicrobial resistance among S pseudintermedius strains is increasing: in the past, susceptibility to most antibiotics was common (Bond and Loeffler 2012), but in the last few years methicillin-resistant S pseudintermedius (MRSP) strains have emerged as a significant animal health problem in veterinary medicine (Schwarz and others 2008, van Duijkeren and others 2008, Wee…

Staphyloccal alpha toxin

1998

Epidural spinal abscesses.

1990

Fifteen cases of peridural empyemas are reported. 12 patients reported with motor dysfunction of the lower extremities and pain radiating from the spine. In one case, localized pain of the spine was discovered and in two cases there were no signs of spinal or radiating pain. Treatment in all cases was laminectomy and systemic antibiotic administration. Microbiological analysis showed staphylococcus aureus in 11 cases. 9 patients recovered with no neurological defects, two had major improvement of the paresis, and one died. Three patients with paraplegia recovered from the primary infection.

1,2,4-Oxadiazole topsentin analogs as staphylococcal biofilm inhibitors targeting the bacterial transpeptidase sortase A

2020

The inhibition or prevention of biofilm formation represents an emerging strategy in the war against antibiotic resistance, interfering with key players in bacterial virulence. This approach includes the inhibition of the catalytic activity of transpeptidase sortase A (Srt A), a membrane enzyme responsible for covalently attaching a wide variety of adhesive matrix molecules to the peptidoglycan cell wall in Gram-positive strains. A new series of seventeen 1,2,4-oxadiazole derivatives was efficiently synthesized and screened as potential new anti-virulence agents. The ability of inhibiting biofilm formation was evaluated against both Gram-positive and Gram-negative pathogens. Remarkably, all…

Potential use of 68Ga-apo-transferrin as a PET imaging agent for detecting Staphylococcus aureus infection.

2010

Abstract Introduction 67 Ga citrate has been extensively used to detect infection and inflammation since 1971. However, its clinical utility is compromised due to several limitations. The present project explored whether 68 Ga- apo -transferrin ( 68 Ga-TF), when prepared in vitro, is a useful agent for positron emission tomography (PET) imaging of bacterial infection. Methods An infection was induced in male Wistar rats by injecting 5×10 5 CFU units of Staphyococcus aureus in the right thigh muscle. 68 Ga-TF was synthesized by mixing 68 GaCl 3 with apo -transferrin (TF, 2 mg) in sodium carbonate (0.1 M, pH 7.0) and incubating at 40°C for 1 h. Animals were injected with 10–15 MBq of 68 Ga-TF…

Neutrophil extracellular traps mediate bacterial liver damage

2015

Neutrophil extracellular traps (NETs) composed of DNA decorated with histones and proteases trap and kill bacteria but also injure host tissue. Here we show that during a bloodstream infection with methicillin-resistant Staphylococcus aureus, the majority of bacteria are sequestered immediately by hepatic Kupffer cells, resulting in transient increases in liver enzymes, focal ischaemic areas and a robust neutrophil infiltration into the liver. The neutrophils release NETs into the liver vasculature, which remain anchored to the vascular wall via von Willebrand factor and reveal significant neutrophil elastase (NE) proteolytic activity. Importantly, DNase although very effective at DNA remov…