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PubMed1990

Microbiologic characteristics of Lactobacillus products used for colonization of the vagina.

Lactobacilli have long been considered to be the protective flora in the vagina. Women with vaginal infections have used various non-prescription products in an attempt to restore their normal vaginal flora. Products that contain lactobacilli include dairy products (yogurt, acidophilus milk) and commercially available Lactobacillus powders and tablets. Recently, Lactobacillus species that produce hydrogen peroxide (H2O2) have been associated with normal vaginal flora. In this study, we compared 16 non-prescription products containing lactobacilli for H2O2 production, purity, and identifiable contaminants. All 16 products contained lactobacilli, of which ten (62%) produced H2O2. At least one contaminant was detected in 11 of 16 (69%) of the products: Enterococcus faecium (ten), Clostridium sporogenes (one), Streptococcus mitis (one), and Pseudomonas species (one). Although all of the products tested contained lactobacilli, only four of the products contained Lactobacillus acidophilus. Most of the lactobacilli-containing products currently available either do not contain the Lactobacillus species advertised and/or contain other bacteria of questionable benefit. We conclude that commercially available products may not be appropriate for recolonization of the vagina.

Bacteria↗
PubMed1980

[Bacterial endocardiitis complicating fibroplastic endocarditis: a case report (author's transl)].

A young Protugese man, who had never travelled outside of Europe, was found to have a bacterial complication of a fibroplastic endocarditis. The onset was by a spontaneous chest pain, associated with a posterolatero-apical subepicardial ischemia and giant T waves in V3, V4, and calcification in the apex of the heart on radiography. Diagnosis was confirmed by intracardiac explorations: ventricular telediastolic pressures were increased; the lower border of the right ventricle was smooth, the left ventricle had a globular appearance with a smooth anterior border, the apex appearing to be completely excluded; coronarography was normal. Histological examination confirmed the presence of fibrosis. Anticoagulant treatment was started. Four months after the onset of the disease, a high fever, an apical systolic murmur, and nine positive blood cultures for a streptococcus mitis, suggested the development of a bacterial endocarditis, though no direct evidence was discovered. Improvement occurred after appropriate antibiotic therapy, and the anticoagulants were continued. Cardiac ultrasonography recordings were normal following this episode. This case-report is of two-fold interest: on the one hand it represents an early form of fibroplastic endocarditis, diagnosed by intracardiac exploration, and on the other hand it emphasizes the rare nature of bacterial complications of this affection. Authors differ in their evaluation of the frequency of chest pain, but their inaugural and isolated nature are rarely described. In most cases the presence of the disease is revealed by a progressive cardiac insufficiency. A very positive factor is the presence of calcifications, and the absence of an eosinophilia does not exclude the diagnosis. Electrical anomalies of the ischemic type are possible, but are rarely isolated findings, and the giant appearance of the T waves in this case is rather atypical. Bacterial complications are rare, and are only reported in 12 of the 218 cases described in the published literature. They are rarely diagnosed during the life of the patient (1 case only). The infection affects the cords, the valves, the thrombus, or the fibrosis itself.

Adult↗
PubMed1995

Contaminated toothbrushes and their disinfection.

Twenty toothbrushes used by healthy subjects were screened for the presence of microorganisms. Microbes were dislodged from the brushes by vortexing, and an average of 4 x 10(3) CFU/mL were recovered from the suspending fluid. Bristles removed from the vortexed brushes still yielded confluent bacterial growth on brain-heart infusion agar medium. Virkon (one per cent), Listerine, Cepacol, Scope, and Plax were tested for their bactericidal effects on microorganisms sedimented from the suspending fluid, on toothbrush bristles and proxabrushes, and on various test species including Candida albicans, Mycobacterium smegmatis, M. bovis, and Streptococcus mitis. Virkon and Listerine killed all the test species and virtually all the microorganisms on the toothbrush bristles and proxabrushes. Six volunteers tested the efficacy of a Listerine soaking regime to prevent the bacterial contamination of toothbrushes. Soaking the toothbrush head (bristles) in Listerine for 20 minutes after brushing was sufficient to eliminate bacterial contamination.

Bacteria↗
PubMed1994

The role of the carbohydrate chains in complement (C3) fixation by solid-phase-bound human IgA.

In contrast to antigen-antibody complexes containing native human IgA, solid-phase-deposited IgA activates the alternative complement pathway and binds C3b. To investigate the role of carbohydrate chains in this, various human IgA preparations were treated with neuraminidase alone or together with N-glycanase or O-glycanase, or with mixed glycosidases from the oral bacterium, Streptococcus mitis. Depletion of oligosaccharides was determined by carbohydrate analysis. Removal of sialic acid and N-linked glycan chains greatly increased the C3b-fixing properties of normal serum IgA1 and IgA2. Myeloma IgA1 and IgA2 proteins and secretory IgA had higher C3b-binding activity than normal serum IgA, and this was further increased by removal of sialic acid and N-linked glycans. Fc alpha and Fc alpha-SC fragments of myeloma and secretory IgA1, respectively, but not Fab alpha fragments, obtained by cleavage with bacterial IgA1 proteases and also free secretory component, fixed C3b by the alternative pathway.

Complement C3b↗
PubMed1994

[Endocarditis caused by Cardiobacterium hominis].

The incidence of endocarditis due to Cardiobacterium hominis is probably underestimated because clinical presentations vary greatly and culture of this Gram negative germ is difficult. A 48-year-old man with a past history of post-streptococcic aortic regurgitation was hospitalized twice within 1 week for fever (38 degrees C) and junctional tachycardia which responded to amiodarone. Subsequently, infero-apical necrosis was documented. Based on the result of the laboratory tests, coronary embolism was suspected although 12 blood cultures were negative. The patient recovered well with a standard antibiotic treatment. Fifteen days later, the blood cultures revealed Cardiobacterium hominis. Antibiotic therapy was adapted and aortic valve replacement was programmed. Two months later the patient died from uncontrollable left heart failure. A 63-year-old man who had had mitral valve replacement 10 years earlier for Streptococcus mitis endocarditis was hospitalized for fever (38 degrees C) and a painful left calf. Phlebocavography eliminated deep vein thrombosis and a complete cardiac work-up was inconclusive. Endocarditis was suspected although blood cultures were negative. The patient was given oral penicillin and discharged after one week. Three months later, the patient was again febrile (38 degrees C) and suffered a cerebral vascular event. Fourteen days after blood sampling, cultures revealed Cardiobacterium hominis. The patient's haemodynamic status worsened and valve replacement with atrioplasty was performed. Outcome after 4 years follow-up has been favourable. Endocarditis due to Cardiobacterium hominis, a saprophitic germ of the upper airway and the female genital tract, has been reported in 64 cases in the literature. The clinical picture is often limited to fever and a heart murmur and laboratory tests show an accelerated erythrocyte sedimentation rate and hyperleukocytosis. Inflammatory type anaemia is often found due to the latency of the endocarditis. Complications are frequent and can be fatal due to massive pulmonary emboli, cerebral vascular events or irreversible heart failure. C. hominis is sensitive to amoxycillin and netilmicin. Surgical treatment of the valvulopathy is indicated.

Anti-Bacterial Agents↗
PubMed1997

[Replacement of the aortic valve with a pulmonary autograft: experience at the University of Verona].

BACKGROUND: Early and long term results after surgical replacement of the aortic valve depend to a large degree on the type of valve substitute used. Pulmonary autograft offers many theoretical advantages, particularly in young patients. METHODS: Between July 1994 and August 1996, 15 patients (12 male) with a mean age of 28 +/- 6 years (range 14 to 36 years) were selected for aortic valve replacement with a pulmonary autograft. The aortic valve disease was isolated insufficiency in 7 cases (47%), stenosis in 3 (20%) and mixed lesion in 5 (33%). One patient in the last group had bacterial endocarditis (Streptococcus mitis). Seven patients (47%) had a bicuspid aortic valve. In 3 cases (20%) the autograft was inserted as a scalloped subcoronary implant. Twelve patients (80%) had total aortic root replacement with re-implantation of the coronary ostia. The right ventricular outflow tract was reconstructed with a cryopreserved homograft (13 pulmonary; 2 aortic). The aortic cross-clamp time was 156 +/- 18 minutes with a total bypass time of 221 +/- 26 minutes. RESULTS: All patients survived the operation. Three postoperative bleeding (20%) necessitated re-exploration. Mean post-operative hospital stay was 10 +/- 2 days. All patients were discharged on aspirin for the period of three months. One patient (7%) with moderate neo-aortic valve insufficiency died suddenly 11 months post-operatively. All survivors are asymptomatic, in NYHA FC 1 at a mean follow-up time of 15.7 months. Freedom from reoperation, valve related complication and endocarditis is 100%. Two-dimensional (2-D) echocardiography six months postoperatively showed a mean left ventricular outflow gradient of 13 +/- 4 mmHg with no evidence of aortic regurgitation in 11 cases (78.5%) and trivial in 3 (21.5%). CONCLUSIONS: Although the Ross operation is technically more challenging and requires a longer operating time than standard procedures, this does not seem to affect early mortality and morbidity. Clinical and haemodynamic results appear to be gratifying. Continued patients evaluation particularly with regard to evidence of valve degeneration and arrhythmias in the long term is warranted.

Adolescent↗
PubMed1997

A numerical taxonomic study of Streptococcus sanguis, S. mitis and similar organisms using conventional tests and pyrolysis mass spectrometry.

Numerical taxonomic methods were applied to the results of pyrolysis mass spectrometry (Py-MS) and conventional test reaction patterns (CTRPs) obtained with 46 strains of oral streptococci identified as representative of six species. Of these: Streptococcus gordonii strains formed a single homogeneous well-differentiated cluster both in the Py-MS and CTRP analyses; S. oralis strains were more diverse, forming 2 CTRP and 3 Py-MS clusters; S. crista, S. parasanguis and S. sanguis formed clear, but diverse and poorly differentiated clusters on the basis of CTRPs, and were poorly differentiated in the Py-MS analysis; and S. mitis strains were clearly diverse in both analyses. Peritrichously fimbriate ('tufted') S. mitis strains formed a tight cluster, well differentiated from the type strain in both Py-MS and CTRP analyses, and may represent a previously unrecognised centre of variation.

Humans↗
PubMed1976

Inhibition of Streptococcus mutans strains by different mitis-salivarius agar preparations.

Several Streptococcus mutans strains were markedly inhibited by mitis-salivarius agar manufactured by Baltimore Biological Laboratories, but little, if any, inhibition was noted using Difco Laboratories' mitis-salivarius agar. Supplementation of the basic medium with sucrose and bacitracin for specific selection of S. mutans resulted in suppression of representative S. mutans type a strains regardless of manufacturer.

Agar↗
PubMed1999

Genetic approaches to the identification of the mitis group within the genus Streptococcus.

The usefulness and reliability of partial sequence analysis of the manganese-dependent superoxide dismutase gene (sodA), autolysin (lytA) gene amplification and species-specific PCR based on the D-alanine:D-alanine ligase (ddl) gene for differentiating each member of the mitis group of the genus Streptococcus was investigated. On the phylogenetic tree based on sodA partial sequences (366 bp) from 96 strains, including all species currently within the mitis group isolated in different geographic areas (mainly Japan and the UK), eight well separated clusters were generated corresponding to recognized species, and all strains fell into those clusters to which they had also been assigned by DNA-DNA hybridization. The Streptococcus pneumoniae sub-cluster was located within the Streptococcus mitis cluster, but the sodA gene of S. pneumoniae was very conserved and therefore could be separated from all other species examined. Furthermore, the lytA gene amplification approach could also be used to differentiate S. pneumoniae from other species. The species-specific amplification product of the ddl gene was successfully detected in Streptococcus sanguinis and Streptococcus gordonii, but failed to be detected in some strains of Streptococcus oralis including the type strain and S. mitis. We conclude that the partial sequence analysis of the sodA gene could be applied globally as a reliable and easy method for the accurate identification of all species currently within the mitis group.

Alanine↗
PubMed2002

Competence without a competence pheromone in a natural isolate of Streptococcus infantis.

Many streptococcal species belonging to the mitis and anginosus phylogenetic groups are known to be naturally competent for genetic transformation. Induction of the competent state in these bacteria is regulated by a quorum-sensing mechanism consisting of a secreted peptide pheromone encoded by comC and a two-component regulatory system encoded by comDE. Here we report that a natural isolate of a mitis group streptococcus (Atu-4) is competent for genetic transformation even though it has lost the gene encoding the competence pheromone. In contrast to other strains, induction of competence in Atu-4 is not regulated by cell density, since highly diluted cultures of this strain are still competent. Interestingly, competence in the Atu-4 strain is lost if the gene encoding the response regulator ComE is disrupted, demonstrating that this component of the quorum-sensing apparatus is still needed for competence development. These results indicate that mutations in ComD or ComE have resulted in a gain-of-function phenotype that allows competence without a competence pheromone. A highly similar strain lacking comC was isolated independently from another individual, suggesting that strains with this phenotype are able to survive in nature in competition with wild-type strains.

Amino Acid Sequence↗
PubMed2004

[Analysis of oral microflora early colonized in infants].

OBJECTIVE: To observe the dynamic changes of oral microflora early colonized in infants. METHODS: The oral swab samples for the study were taken in 1 day, 1, 3, 6, 9, 12 months after birth from 12 healthy neonates. By choosing suitable diluted concentration, the samples were incubated aerobically, facultative anaerobically and anaerobically. The strains were identified by observing colony characteristics, Gram staining and biochemical tests. RESULTS: S. salivarius was the most frequent microflora, followed by S. mitis, S. sanguis, S. gordonii and S. mutans occurred in oral cavity after tooth eruption. Veillonella spp. can be detected in oral cavity of 1-month-old babies, A. odontolyticus was isolated from 8.3% infants of more than 3 months old. L. acidophilus maintained the lower prevalence in oral cavity of babies. Leptotrichia buccalis and Capnocytophaga spp. occurred in oral cavity of some dentate infants. CONCLUSION: S. solivarius and S. mitis are predominant species in oral cavity of the infants, Veillonella spp. is the first and the most anaerobic species appeared in oral cavity of healthy babies. A. odontolyticus is the first actinomyces detected in oral cavity. With the increasing months, kind and amount of microflora increase dramatically.

Actinomyces↗
PubMed2006

The effect of Piper betle and Psidium guajava extracts on the cell-surface hydrophobicity of selected early settlers of dental plaque.

The adhesion of early settlers of dental plaque to the tooth surface has a role in the initiation of the development of dental plaque. The hydrophobic surface properties of the bacteria cell wall are indirectly responsible for the adhesion of the bacteria cell to the acquired pellicle on the tooth surfaces. In this study, the effect of aqueous extract of two plants (Psidium guajava and Piper betle) on the cell-surface hydro-phobicity of early settlers of dental plaque was determined in vitro. Hexadecane, a hydrocarbon was used to represent the hydrophobic surface of the teeth in the oral cavity. It was found that treatment of the early plaque settlers with 1 mg/ml extract of Psidium guajava reduced the cell-surface hydrophobicity of Strep. sanguinis, Strep. mitis and Actinomyces sp. by 54.1%, 49.9% and 40.6%, respectively. Treatment of these bacteria with the same concentration of Piper betle however, showed a comparatively lesser effect (< 10%). It was also observed that the anti-adhesive effect of the two extracts on the binding of the early plaque settlers to hexadecane is concentration dependent.

Actinomyces↗
PubMedDate not supplied

Evaluation of clinical and microbiological features of deep carious lesions in primary molars.

PURPOSE: Concern about the survival of microorganisms in deep carious lesions may often lead to unnecessary exposure of the pulp during excavation. This study evaluated the relationship between microbiological and clinical results of deep carious lesions in primary molars. METHODS: Clinical evaluation was performed on 72 deep carious lesions considered to have pulp perforation after traditional excavation. The dentin color and consistency were assessed by means of standardized scales using the technique of Bjorndal et al before restoration. For microbiological examination, dentin samples were taken by a sterile bur and transferred to transport fluid, then plated on tryptic soy agar for growth of total colony forming units. Samples werethen transferred on Rogosa SL agar for growth of oral lactobacilli and on mitis salivarius agar for growth of mutans streptococci. RESULTS: The proportion of mutans streptococci, lactobacilli, and total colony forming units increased when the dentin color and consistency increased. However, the proportion of lactobacilli was smaller than that of mutans streptococci in carious dentin samples. CONCLUSIONS: Contrary to expectations, the findings showed that the number of bacteria in carious dentin of primary molars was not significantly excessive.

Child↗
PubMed2003

The anti-adherence effect of Piper betle and Psidium guajava extracts on the adhesion of early settlers in dental plaque to saliva-coated glass surfaces.

The aqueous extracts of Piper betle and Psidium guajava were prepared and tested for their anti-adherence effect on the adhesion of early plaque settlers (Strep. mitis, Strep. sanguinis and Actinomyces sp.). The saliva-coated glass surfaces were used to simulate the pellicle-coated enamel surface in the oral cavity. Our results showed that the anti-adherence activities of Piper betle and Psidium guajava extracts towards the bacteria were different between the bacterial species. Psidium guajava was shown to have a slightly greater anti-adherence effect on Strep. sanguinis by 5.5% and Actinomyces sp. by 10% and a significantly higher effect on Strep. mitis (70%) compared to Piper betle. The three bacterial species are known to be highly hydrophobic, and that hydrophobic bonding seemed to be an important factor in their adherence activities. It is therefore suggested that the plant extracts, in expressing their anti-adherence activities, could have altered the hydrophobic nature of the bonding between the bacteria and the saliva-coated glass surfaces.

Actinomyces↗
PubMed2005

Effect of a stannous fluoride dentifrice on the sulcular microbiota: a prospective cohort study in subjects with various levels of periodontal inflammation.

OBJECTIVES: To assess the effects of an experimental 0.454% stannous fluoride (SnF2) dentifrice on the oral sulcular microbiota in patients with various stages of oral diseases using checkerboard DNA-DNA hybridization. MATERIAL AND METHODS: In the present one-month, single center, single product, prospective cohort trial, 37 adults (mean age 37.6) were assigned to one of four oral health condition cohorts with seven to 10 subjects each: 1. mild gingivitis, 2. marked generalized gingivitis to moderate periodontitis, 3. caries-prone and 4. treated moderate to advanced chronic periodontitis in supportive periodontal care. All four groups were asked to use the test dentifrice and a power toothbrush twice a day for one minute during a four-week test period. Before and after the trial period, Plaque Indices (PII, Silness and Löe, 1964) and Gingival Indices (GI, Löe and Silness, 1963) were recorded. Subgingival plaque samples were collected from all patients at Baseline, as well as after two and four weeks. These samples were analyzed for content of 40 bacterial species using checkerboard DNA-DNA hybridization. RESULTS: As a result of the only one minute brushing with the stannous fluoride dentifrice, the mean PII at Baseline was significantly lower (p < 0.05) from the mean PII at four weeks. No statistically significant differences were found between premolar and molar mean values. Moreover, no statistically significant differences were found between the mean GI at Baseline and at four weeks. The microbiological analysis showed that at baseline subjects in groups 2 and 4 had significantly higher bacterial loads of bacteria than groups 1, and 3 (i.e. A. actinomyctemcomitans P. gingivalis, T. forsythia, and T. denticola. Over the study period, the total bacterial load did not change in groups 2, 3 and 4. In groups 1 and 3, however, an increase in the loads of Streptococci spp. were noticed (p < 0.05) including S. mitis, S. intermedius, and S. sanguis (p < 0.01) suggesting an increase in the presence of early colonizing and health associated bacteria. CONCLUSION: One minute brushing with a 0.454% stannous fluoride dentifrice did--after four weeks--not affect the subgingival microbial profiles in patients with moderate periodontitis and treated moderate to advanced periodontitis. However, the sulcular microbial profiles of mild gingivitis and caries-prone patients were affected, indicating a shift towards a gingival health associated microbiota in the sulcular region of patients not affected by attachment loss. RUNNING HEAD: Effect of stannous fluoride on sulcular microbiota.

Adult↗
PubMed2003

A rapid solid-phase fluorimetric assay for measuring bacterial adherence, using DNA-binding stains.

In this report, we describe the validation of a rapid, single-step, microtiter plate method for quantifying bacterial adherence, based on fluorescent labeling of microorganisms with cell-permeable fluorescent DNA-binding probes. We have tested the binding to saliva-coated microtiter plates of bacteria, including Helicobacter pylori and viridans streptococci (S. mitis, S. gordonii, S. sanguis), known to interact with salivary components. Furthermore, we tested the short-term and longer-term temporal stability of a saliva-mediated adherence of these bacteria in a healthy population (N=30). The assay exhibited excellent reliability statistics, yielding within-assay variability coefficients ranging from 4.9% to 11%. A range of approximately 5 x 10(4)-1 x 10(7) cells could be detected. This method may be generally applicable to study surface binding of virtually any microbial species, while obviating the need of radioactive materials or specific antibodies for quantification, thus providing a procedure that is useful to both basic and clinical research.

Bacterial Adhesion↗
PubMed2004

Pneumolysin is a key factor in misidentification of macrolide-resistant Streptococcus pneumoniae and is a putative virulence factor of S. mitis and other streptococci.

We evaluated the applicability of ply PCR for confirmation of the identification of Streptococcus pneumoniae. lytA PCR, 16S rRNA sequencing, and amplified-fragment length polymorphism were used as reference methods. In contrast to the lytA gene, the ply gene proved to be not specific for S. pneumoniae. The presence of the ply gene in other streptococci, in particular Streptococcus mitis, suggests that pneumolysin plays a pathogenic role.

Bacterial Proteins↗