: Case report and literature review.

Non-diphtheria species have been increasingly recognized as multidrug resistant pathogens that also infect immunocompromised patients. Automated and semi-automated phenotypic tests have been used by clinical laboratories for detection of these gram-positive rods. The present case report describes the rare pediatric case of isolated in central venous catheter blood cultures during chemotherapy treatment for Wilms tumor and adds to the knowledge on this infection with regard to pediatric cancer.

Bloodstream and catheter-related infections due to different clones of multidrug-resistant and biofilm producer Corynebacterium striatum.

Background: Corynebacterium striatum is an emerging multidrug-resistant (MDR) pathogen associated with immunocompromised and chronically ill patients, as well as nosocomial outbreaks. In this study, we characterized 23 MDR C. striatum isolated of bloodstream and catheter-related infections from a hospital of Rio de Janeiro.

Epidemiological and clinical profile of infective endocarditis at a Brazilian tertiary care center: an eight-year prospective study.

Introduction: Infective endocarditis (IE) is a systemic infectious disease requiring a multidisciplinary team for treatment. This study presents the epidemiological and clinical data of 73 cases of IE in Rio de Janeiro, Brazil.

Methods: This observational prospective cohort study of endocarditis patients during an eight-year study period described 73 episodes of IE in 70 patients (three had IE twice).

Evaluation of polymethyl methacrylate containing chlorhexidine: A randomized, controlled, split-mouth in situ study.

Purpose: To evaluate the antimicrobial action and elemental composition of chlorhexidine (CHX) diacetate in acrylic resins based on PMMA (polymethyl methacrylate) in situ. In addition, ex vivo evaluation of the CHX release mechanism was performed over a 14-day period.

Methods: Three discs of PMMA incorporating CHX and three control discs were mounted on individual oral splints and exposed to the oral cavity of 32 participants for 24 hours.

Endocarditis due to in a kidney transplanted patient: case report and review of medical literature.

Endocarditis caused by yeasts is currently an emerging cause of infective endocarditis and, when accompanied byfever of unknown origin, is more severe since interferes with proper diagnosis and endocarditis treatment. The Rio de Janeiro Infective Endocarditis Study Group reports a case of infectious endocarditis (IE) with negative blood cultures in a 45-year-old white female resident in Rio de Janeiro, Brazil, previously submitted to kidney transplantation. After diagnosis and intervention, the valve culture revealed .

Evaluation of two disinfection/sterilization methods on silicon rubber-based composite finishing instruments.

Purpose: To evaluate the effectiveness of disinfection/sterilization methods and their effects on polishing capacity, micomorphology, and composition of two different composite fiishing and polishing instruments.

Methods: Two brands of finishing and polishing instruments (Jiffy and Optimize), were analyzed. For the antimicrobial test, 60 points (30 of each brand) were used for polishing composite restorations and submitted to three different groups of disinfection/sterilization methods: none (control), autoclaving, and immersion in peracetic acid for 60 minutes.

Tellurite resistance: a putative pitfall in Corynebacterium diphtheriae diagnosis?

Corynebacterium diphtheriae strains continue to circulate worldwide causing diphtheria and invasive diseases, such as endocarditis, osteomyelitis, pneumonia and catheter-related infections. Presumptive C. diphtheriae infections diagnosis in a clinical microbiology laboratory requires a primary isolation consisting of a bacterial culture on blood agar and agar containing tellurite (TeO3(2-)).

Corynebacterium diphtheriae putative tellurite-resistance protein (CDCE8392_0813) contributes to the intracellular survival in human epithelial cells and lethality of Caenorhabditis elegans.

Corynebacterium diphtheriae, the aetiologic agent of diphtheria, also represents a global medical challenge because of the existence of invasive strains as causative agents of systemic infections. Although tellurite (TeO32-) is toxic to most microorganisms, TeO32--resistant bacteria, including C. diphtheriae, exist in nature.

Biofilm production by multiresistant Corynebacterium striatum associated with nosocomial outbreak.

Corynebacterium striatum is a potentially pathogenic microorganism that causes nosocomial outbreaks. However, little is known about its virulence factors that may contribute to healthcare-associated infections (HAIs). We investigated the biofilm production on abiotic surfaces of multidrug-resistant (MDR) and multidrug-susceptible (MDS) strains of C.

Biofilm formation and fibrinogen and fibronectin binding activities by Corynebacterium pseudodiphtheriticum invasive strains.

Biofilm-related infections are considered a major cause of morbidity and mortality in hospital environments. Biofilms allow microorganisms to exchange genetic material and to become persistent colonizers and/or multiresistant to antibiotics. Corynebacterium pseudodiphtheriticum (CPS), a commensal bacterium that colonizes skin and mucosal sites has become progressively multiresistant and responsible for severe nosocomial infections.

Efficacy of chemomechanical caries removal in reducing cariogenic microbiota: a randomized clinical trial.

The aim of this study was to compare the efficacy of chemochemical methods (Carisolv™ and Papacárie®) versus the manual method (excavators) in reducing the cariogenic microbiota in dentine caries of primary teeth. Forty-six healthy children (5 to 9 years old) having at least one primary tooth with a cavitated dentine carious lesion were included in the study. The teeth presented no clinical or radiographic signs of pulpal involvement.

Adherence to abiotic surface induces SOS response in Escherichia coli K-12 strains under aerobic and anaerobic conditions.

During the colonization of surfaces, Escherichia coli bacteria often encounter DNA-damaging agents and these agents can induce several defence mechanisms. Base excision repair (BER) is dedicated to the repair of oxidative DNA damage caused by reactive oxygen species (ROS) generated by chemical and physical agents or by metabolism. In this work, we have evaluated whether the interaction with an abiotic surface by mutants derived from E.

Molecular identification of nocardia isolates from clinical samples and an overview of human nocardiosis in Brazil.

Background: Nocardia sp. causes a variety of clinical presentations. The incidence of nocardiosis varies geographically according to several factors, such as the prevalence of HIV infections, transplants, neoplastic and rheumatic diseases, as well as climate, socio-economic conditions and laboratory procedures for Nocardia detection and identification.

Antimicrobial resistance and virulence traits of Enterococcus faecalis from primary endodontic infections.

Objectives: To determine the phenotypic and molecular characteristics of Enterococcus faecalis recovered from primary endodontic infections in Brazilian patients.

Methods: Twenty isolates of E. faecalis recovered from 43 Brazilian patients with primary endodontic infections were identified by biochemical profiling (API20Strep) and 16S rDNA sequencing.

Clonal multidrug-resistant Corynebacterium striatum within a nosocomial environment, Rio de Janeiro, Brazil.

Corynebacterium striatum is a potentially pathogenic microorganism with the ability to produce outbreaks of nosocomial infections. Here, we document a nosocomial outbreak caused by multidrug-resistant (MDR) C. striatum in Rio de Janeiro, Brazil.

Aggregative adherent strains of Corynebacterium pseudodiphtheriticum enter and survive within HEp-2 epithelial cells.

Corynebacterium pseudodiphtheriticum is a well-known human pathogen that mainly causes respiratory disease and is associated with high mortality in compromised hosts. Little is known about the virulence factors and pathogenesis of C. pseudodiphtheriticum.

Corynebacterium diphtheriae 67-72p hemagglutinin, characterized as the protein DIP0733, contributes to invasion and induction of apoptosis in HEp-2 cells.

Although Corynebacterium diphtheriae has been classically described as an exclusively extracellular pathogen, there is growing evidence that it may be internalized by epithelial cells. The aim of the present report was to investigate the nature and involvement of the surface-exposed non-fimbrial 67-72 kDa proteins (67-72p), previously characterized as adhesin/hemagglutinin, in C. diphtheriae internalization by HEp-2 cells.

Corynebacterium ulcerans diphtheria: an emerging zoonosis in Brazil and worldwide.

The article is a literature review on the emergence of human infections caused by Corynebacterium ulcerans in many countries including Brazil. Articles in Medline/PubMed and SciELO databases published between 1926 and 2011 were reviewed, as well as articles and reports of the Brazilian Ministry of Health. It is presented a fast, cost-effective and easy to perform screening test for the presumptive diagnosis of C.

The role of DNA base excision repair in filamentation in Escherichia coli K-12 adhered to epithelial HEp-2 cells.

Base excision repair (BER) is dedicated to the repair of oxidative DNA damage caused by reactive oxygen species generated by chemical and physical agents or by metabolism which can react with DNA and cause a variety of mutations. Epithelial cells are typically the first type of host cell to come into contact with potential microbial invaders. In this work, we have evaluated whether the adherence to human epithelial cells causes DNA damage and associated filamentation.

Fibrinogen binds to nontoxigenic and toxigenic Corynebacterium diphtheriae strains.

The production of fibrinous exudates may play an important role in determining the outcome of bacterial infection. Although pseudomembrane formation is a characteristic feature of diphtheria, little is known about the fibrinogen (Fbn)-binding properties of Corynebacterium diphtheriae strains and the influence of the gene that codes for diphtheria toxin (tox gene) in this process. In this study we demonstrated the ability of C.

The antimicrobial activity of gray-colored mineral trioxide aggregate (GMTA) and white-colored MTA (WMTA) under aerobic and anaerobic conditions.

Objective: The objective of this study was to test the hypothesis that the antimicrobial activity of gray-colored MTA (GMTA) and white-colored MTA (WMTA) is related to the induction of reactive oxygen species (ROS).

Study Design: In vitro antimicrobial activity of MTA was carried out using E. coli mutant (AB2463-RecA13), triple mutant (BW535), and wild type (AB1157).

Non-opsonic phagocytosis of homologous non-toxigenic and toxigenic Corynebacterium diphtheriae strains by human U-937 macrophages.

As interactions between bacteria and macrophages dictate the outcome of most infectious diseases, analyses of molecular mechanisms of non-opsonic phagocytosis should lead to new approaches for the prevention of diphtheria and systemic Corynebacterium diphtheriae infections. The present study aimed to evaluate human macrophage-bacteria interactions in the absence of opsonin antibodies and the influence of the tox gene on this process. Homologous C.

Cytotoxicity evaluation of two root canal sealers and a commercial calcium hydroxide paste on THP1 cell line by Trypan Blue assay.

Objective: The aim of this investigation was to evaluate the cytotoxicity of two brands of root canal sealers, epoxy-resin based and zinc oxide-eugenol based, and one commercial calcium hydroxide paste on a monocyte cell line THP-1.

Material And Methods: Undiluted (crude extract) and diluted extracts to 10%, 1%, 0.1%, 0.