Sir, Many studies have demonstrated a trend towards decreased antimicrobial susceptibility in viridans group streptococci isolated from blood cultures.1,2 This raises concerns when this group of organisms cause more serious infections, such as infective endocarditis, when penicillin resistance can create therapeutic difficulties.3 However, few routine data are available on the susceptibility of...

The aim of this study was to evaluate and compare the antimicrobial activity and cytocompatibility of six different pulp-capping materials: Dycal (Dentsply), Calcicur (Voco), Calcimol LC (Voco), TheraCal LC (Bisco), MTA Angelus (Angelus), and Biodentine (Septodont). To evaluate antimicrobial activity, materials were challenged in vitro with Streptococcus mutans, Streptococcus salivarius, and St...

The basis of the bactericidal activity of human lysozyme against Streptococcus sanguis was studied. Experiments were designed to evaluate the role of lysozyme muramidase activity in its bactericidal potency. Inactivation of the muramidase activity of lysozyme was achieved by reduction of essential disulfides with dithiothreitol (DTT) or by incubation with the chitin oligosaccharides chitotriose...

Infection with either Streptococcus sanguis or Streptococcus pneumoniae type 25 causes acute pneumonitis in rats. Pneumonia caused by S. sanguis resolves over the course of 8 d, whereas pneumonia caused by S. pneumoniae type 25 progresses to fibrosis. To examine the role of apoptosis in these models, we performed assays with the terminal deoxynucleotidyltransferase-uridine nucleotide end-labeli...

Resistance in streptococci or Gram-negative bacteria is associated with antibiotic consumption. Scarce information exists on the antibiotic susceptibility of bacterial isolates from patients with periodontitis in countries with high antibiotic consumption, as this is an area in which microbiological testing is not performed in daily practice. The present study was undertaken to explore the susc...

BACKGROUND Antimicrobial agents have been used as a chemotherapeutic agent to improve oral health. This in vitro study was carried out to determine the antimicrobial activity of ten Iranian-made toothpastes against commonly found bacteria in the oral cavity. METHODS The microorganisms used in this study were Streptococcus mutans, Streptococcus sanguis, Actinomyces viscosus and Candida albican...

The influences of IgA hinge length and composition on its susceptibility to cleavage by bacterial IgA1 proteases were examined using a panel of IgA hinge mutants. The IgA1 proteases of Streptococcus pneumoniae, Streptococcus sanguis strains SK4 and SK49, Neisseria meningitidis, Neisseria gonorrhoeae, and Haemophilus influenzae cleaved IgA2-IgA1 half hinge, an Ab featuring half of the IgA1 hinge...

OBJECTIVE The mucosal secretory proteins, such as the salivary proteins, play a key role in the acquisition and regulation of the mucosal microflora. Most notably, some microorganisms utilize the host's secretory proteins to adhere to the mucosa; a first step in colonization and infection. The secretory proteins also influence colonization by affecting the binding among microorganisms, a proces...

statement of problem: streptococcus viridans is one of the most important micro-organisms in the establishment of infections leading to dental caries and heart valve damages. therefore the diagnosis and prevention of these infections is critical in health care. purpose: the aim of this in-vivo study was to determine the prevalence of viridans streptococci in abscesses occurring in the maxillofa...