BACKGROUND: Viridans group streptococci (VGS) are being increasingly reported as pathogens causing septicemia in neutropenic and other immunocompromised patients since 1980s. In the past, VGS were nearly uniformly susceptible to beta-lactam antimicrobial agents, aminoglycosides, tetracyclines, and macrolides. Several recent published studies, however, indicate that antimicrobial resistance may be emerging as a problem with VGS. The purpose of this study was to determine the antimicrobial susceptibility of VGS strains isolated from blood cultures in recent period. METHODS: A total of 45 consecutive strains of VGS isolated from blood cultures between May 2001 and March 2002 at Wonju Christian Hospital were tested for antimicrobial susceptibility. Identification of VGS were performed by API Strep 32(bioMerieux sa, Marcy-l'Etoile, France) commercial kit. Antimicrobial susceptibility tests were done by NCCLS recommended disk diffusion method and penicillin MICs were determined by E test. RESULTS: Among the 45 VGS strains, frequently isolated organisms were Streptococcus mitis (31.1%), Streptococcus oralis (17.8%), Streptococcus constellatus (11.1%), and Streptococcus anginosus (8.9%). Overall intermediate-and resistant rates to antimicrobial agents of VGS were as follows: penicillin; 26.7% and 8.9%, erythromycin; 4.4% and 28.9%, clindamycin 2.2% and 22.2%, and ceftriaxone; 4.4% and 6.7%, respectively. Resistant rates of Streptococcus mitis and Streptococcus oralis were as follows: penicillin; 50% vs 50%, erythromycin 43% vs 37%, clindamycin 21% vs 37%, and ceftriaxone 7% vs 25%, respectively. CONCLUSIONS: These results indicate the species-related variability of susceptibility among VGS isolated from blood in recent period. In addition to S. mitis, S. oralis also displayed high rates of resistance to penicillin, macrolides, and ceftriaxone. The difference in susceptibilities between species of VGS indicates the importance of accurate identification and the need for continuing monitoring of antimicrobial resistance.
Aminoglycosides ; Anti-Infective Agents ; Ceftriaxone ; Clindamycin ; Diffusion ; Erythromycin ; Gangwon-do ; Immunocompromised Host ; Macrolides ; Penicillin Resistance ; Penicillins ; Sepsis ; Streptococcus anginosus ; Streptococcus constellatus ; Streptococcus mitis ; Streptococcus oralis ; Tetracyclines ; Viridans Streptococci*

LIVE/DEAD(R) BacLight(TM) and alamarBlue(R) are fluorescent materials used for the enumeration of live and dead bacteria. LIVE/DEAD(R) BacLight(TM) is generally used for confocal microscopy applications to differentiate live from dead bacteria in a biofilm or planktonic state. AlamarBlue(R) has also been used widely to assay live and dead bacteria in a planktonic state. Whilst these materials are successfully utilized in experiments to discriminate live from dead bacteria for several species of bacteria, the application of these techniques to oral bacteria is limited to the use of LIVE/DEAD(R) BacLight(TM) in biofilm studies. In our present study, we assessed whether these two methods could enumerate live and dead oral bacterial species in a planktonic state. We tested the reagents on Streptococcus mutans, Streptococcus sobrinus, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans and Enterococcus faecalis and found that only LIVE/DEAD(R) BacLight(TM) could differentiate live from dead cells for all five of these oral strains. AlamarBlue(R) was not effective in this regard for P. gingivalis or A. actinomycetemcomitans. In addition, the differentiation of live and dead bacterial cells by alamarBlue(R) could not be performed for concentrations lower than 2 x 10(6) cells/ml. Our data thus indicate that LIVE/DEAD(R) BacLight(TM) is a more effective reagent for this analysis.
Bacteria ; Biofilms ; Enterococcus faecalis ; Fluorescence ; Indicators and Reagents ; Microbial Viability ; Microscopy, Confocal ; Oxazines ; Plankton ; Porphyromonas gingivalis ; Streptococcus mutans ; Streptococcus sobrinus ; Viridans Streptococci ; Xanthenes

Mitis group streptococci (MGS) were classified based on the nucleotide sequences 16S rRNA gene (16S rDNA) and comprised 13 Streptococcus species. However, 16S rDNA homogeneity among MGS was too high to discriminate between clinical strains at the species level, notably between Streptococcus mitis, Streptococcus oralis, Streptococcus pneumoniae, and Streptococcus pseudopneumoniae. The purpose of this study was to discriminate between 37 strains of MGS isolated from Korean oral cavities using phylogenetic analysis of the DNA-dependant RNA polymerase beta-subunit gene (rpoB). 16S rDNA and rpoB from clinical strains of MGS were sequenced using the dideoxy chain termination method and analyzed using MEGA version 5 software. The resulting phylogenetic data showed that the rpoB sequences could delineate clinical strains of MGS at the species level. Phylogenetic analysis of rpoB is therefore a useful approach for identifying MGS at the species level.
Base Sequence ; Discrimination (Psychology) ; DNA, Ribosomal ; DNA-Directed RNA Polymerases ; Genes, rRNA ; Streptococcus ; Streptococcus mitis ; Streptococcus oralis ; Streptococcus pneumoniae

Human mouth environment is known to include a variety bacteria, including Streptococcus spp., Staphylococcus spp., Actinomyces spp., Lactobacillus spp., Candida spp., Enterobacteriaceae, et al. Human oral microorganisms can cause dental caries, gingivitis, periodontitis, respiratory tract infection, and cardiovascular disease. Thus, right denture cleaning is essential to oral and general human health. The aim of this study was to evaluate the bactericidal effect of a sodium dichloroisocyanurate-based effervescent tablet (Aos Denti Germ, Aos Company, Chungbuk, Korea) against oral microorganisms. A total of 5 species Streptococcus spp. (Streptococcus anginosus, Streptococcus mitis, Streptococcus mutans, Streptococcus oralis, and Streptococcus sobrinus), Actinomyces oris, Candida albicans, and Escherichia coli were used in this study. All strains were exposed to the distilled water prepared with effervescent tablet. After the exposure, the mixture of strains and effervescent tablet was inoculated onto blood agar or MacConkey agar plate and cultured at 36℃. All strains were killed immediately on exposure to effervescent tablet. The results suggested that effervescent tablet could be used as an effective denture cleanser for dental hygiene.
Actinomyces ; Agar ; Bacteria ; Candida ; Candida albicans ; Cardiovascular Diseases ; Chungcheongbuk-do ; Dental Caries ; Denture Cleansers ; Dentures* ; Enterobacteriaceae ; Escherichia coli ; Gingivitis ; Humans ; Lactobacillus ; Mouth ; Oral Hygiene ; Periodontitis ; Respiratory Tract Infections ; Sodium ; Staphylococcus ; Streptococcus ; Streptococcus mitis ; Streptococcus mutans ; Streptococcus oralis ; Water

OBJECTIVE: To determine the causative organisms and predisposing factors of bacteremia in patients with systemic lupus erythemaosus (SLE). METHODS: We retrospectively evaluated medical records of 358 patients with SLE who were followed in Kangnam St. Mary? Hospital from 1992 to 1997. Bacteremic SLE patients were compared to non-bacteremic SLE patients in terms of laboratory and clinical variables. RESULTS: Twenty-nine episodes of bacteremia in 27 patients with SLE (26 women, 1 man) were identified. The episode of community acquired bacteremia (n=21, 72.4%) was more frequent than that of hospital acquired bacteremia (n=8, 27.6%). Isolated bacterial organisms from blood were as follows: gram negative organisms (n=14); Salmonella species (n=8), E. coli (n=4), P. mirabilis (n=1), K. pneumonia (n=1). gram positive organisms (n=15); S. aureus (n=6), Streptococcus pneumoniae (n=2), coagulase negative Staphylococci (n=2), Bacillus species (n=1), Streptococcus viridans (n=1), Streptococcus pyogenes (n=1), Enterococcus faecalis (n=1), Listeria monocytogenes (n=1). SLE was the most common underlying condition among Salmonella bacteremic patients. One of twenty seven bacteremic SLE patients (3.8%) died in spite of antibiotic therapy. Logistic regression analysis of the laboratory and clinical variables between bacteremic SLE patients and non-bacteremic SLE patients (n=140) showed that bacteremic SLE patients were more frequently associated with thrombocytopenia (p=0.008, odds ratio (OR)=7.8, 95% confidence interval (CI), 1.7 to 35.9), lupus nephritis (p=0.023, OR=5.3, 95% CI, 1.1 to 26.8), and high dose steroid therapy (prednisolone > 0.5mg/kg/day, p=0.008, OR=12.1, 95% CI 2.5 to 58.6) than non-bacteremic SLE patients. CONCLUSION: Our data suggested that Salmonella was the single most frequent isolate from the blood of SLE patients. Lupus nephritis and high dose steroid therapy were independent predisposing factors for the development of bacteremia in SLE patients.
Bacillus ; Bacteremia* ; Causality ; Coagulase ; Enterococcus faecalis ; Female ; Humans ; Listeria monocytogenes ; Logistic Models ; Lupus Erythematosus, Systemic* ; Lupus Nephritis ; Medical Records ; Mirabilis ; Odds Ratio ; Pneumonia ; Retrospective Studies ; Salmonella ; Streptococcus pneumoniae ; Streptococcus pyogenes ; Thrombocytopenia ; Viridans Streptococci

OBJECTIVE: To determine the causative organisms and predisposing factors of bacteremia in patients with systemic lupus erythemaosus (SLE). METHODS: We retrospectively evaluated medical records of 358 patients with SLE who were followed in Kangnam St. Mary? Hospital from 1992 to 1997. Bacteremic SLE patients were compared to non-bacteremic SLE patients in terms of laboratory and clinical variables. RESULTS: Twenty-nine episodes of bacteremia in 27 patients with SLE (26 women, 1 man) were identified. The episode of community acquired bacteremia (n=21, 72.4%) was more frequent than that of hospital acquired bacteremia (n=8, 27.6%). Isolated bacterial organisms from blood were as follows: gram negative organisms (n=14); Salmonella species (n=8), E. coli (n=4), P. mirabilis (n=1), K. pneumonia (n=1). gram positive organisms (n=15); S. aureus (n=6), Streptococcus pneumoniae (n=2), coagulase negative Staphylococci (n=2), Bacillus species (n=1), Streptococcus viridans (n=1), Streptococcus pyogenes (n=1), Enterococcus faecalis (n=1), Listeria monocytogenes (n=1). SLE was the most common underlying condition among Salmonella bacteremic patients. One of twenty seven bacteremic SLE patients (3.8%) died in spite of antibiotic therapy. Logistic regression analysis of the laboratory and clinical variables between bacteremic SLE patients and non-bacteremic SLE patients (n=140) showed that bacteremic SLE patients were more frequently associated with thrombocytopenia (p=0.008, odds ratio (OR)=7.8, 95% confidence interval (CI), 1.7 to 35.9), lupus nephritis (p=0.023, OR=5.3, 95% CI, 1.1 to 26.8), and high dose steroid therapy (prednisolone > 0.5mg/kg/day, p=0.008, OR=12.1, 95% CI 2.5 to 58.6) than non-bacteremic SLE patients. CONCLUSION: Our data suggested that Salmonella was the single most frequent isolate from the blood of SLE patients. Lupus nephritis and high dose steroid therapy were independent predisposing factors for the development of bacteremia in SLE patients.
Bacillus ; Bacteremia* ; Causality ; Coagulase ; Enterococcus faecalis ; Female ; Humans ; Listeria monocytogenes ; Logistic Models ; Lupus Erythematosus, Systemic* ; Lupus Nephritis ; Medical Records ; Mirabilis ; Odds Ratio ; Pneumonia ; Retrospective Studies ; Salmonella ; Streptococcus pneumoniae ; Streptococcus pyogenes ; Thrombocytopenia ; Viridans Streptococci

OBJECTIVE: To explore the effects of intervention with oral probiotic METHODS: This study were conducted among 155 women in the third trimester of pregnancy with positive results of GBS culture in the Outpatient Department of Zhujiang Hospital from March to November, 2019. After excluding 32 patients who received lactobacillus intervention for less than 2 weeks or underwent postpartum GBS retesting, the women were divided into oral probiotics intervention group (60 cases) and non-intervention group (63 cases). According to the results of GBS retesting, the 60 women in the intervention group were divided into GBS-negative group (18 cases) and persistent GBS-positive group (42 cases). At the end of the intervention, the rates of negative GBS culture result were calculated and the pregnancy outcomes were compared. From 5 women randomly selected from the intervention group, samples of vaginal secretions were collected before and after the intervention for amplicon sequencing and bioinformatics analysis. RESULTS: At the end of the intervention, the GBS-negative rate in the intervention group was 30% (18/60), as compared with 23% (3/13) in the non-intervention group. Probiotic intervention significantly reduced the incidence of premature rupture of membranes ( CONCLUSIONS Intervention with oral probiotics can reduce vaginal GBS colonization in late pregnancy and improve the pregnancy outcome.
Female ; Humans ; Lactobacillus reuteri ; Lactobacillus rhamnosus ; Microbiota ; Pregnancy ; Probiotics/therapeutic use* ; Streptococcus agalactiae ; Vagina

This study aimed to evaluate the antimicrobial effects of Acanthopanax sessiliflorum fruit (ASF; Ogaza) extracts on Streptococcus mutans and Streptococcus sobrinus, which are agents that cause dental caries, and on Streptococcus mitis and Streptococcus salivarius, the microbial flora of the oral cavity. The ASF extracts obtained using 70% ethanol were fractionated in the order of ethyl acetate and n-Butanol, concentrated under reduced pressure, and lyophilized to give powdery solvent extracts. The antimicrobial activity of ASF extracts from each solvent was examined using the disk diffusion method. As a result, only those extracts obtained using an ethyl acetate solvent showed antimicrobial activity. These extracts were selected, and the minimum inhibitory concentration was measured by disk diffusion method at various extract concentrations. Results showed a minimum inhibitory concentration of 32 mg/ml. The viable cell count was measured to confirm the minimum bactericidal concentration. Results showed a minimum bactericidal concentration of 64 mg/ml. In the cytotoxicity test using normal human dermal fibroblast cells, the absorbance value of the test group was similar to that of the control group at 0.64, 1.28, and 6.4 mg/ml. The bacteria and their colonies were examined using a scanning electron microscope. Boundaries between the antimicrobial activity region and non-antimicrobial activity region were observed around the paper disk, which was immersed in the extract with 32 mg/ml concentration. Bacterial colonization was not observed in the area with antimicrobial activity. This finding suggests that ASF extracts can inhibit the growth of some microorganisms in the oral cavity, in addition to the effects of these extracts known to date. In particular, ASF extracts may be used as a preparation for preventing dental caries by adding the extract to the toothpaste or oral mouthwash.
1-Butanol ; Bacteria* ; Cell Count ; Colon ; Dental Caries ; Diffusion ; Eleutherococcus* ; Ethanol ; Fibroblasts ; Fruit* ; Humans ; Methods ; Microbial Sensitivity Tests ; Mouth ; Streptococcus ; Streptococcus mitis ; Streptococcus mutans ; Streptococcus sobrinus ; Toothpastes

OBJECTIVETo evaluate the effects of Yili dark bee propolis on the main cariogenic biofilm and mechanisms.

METHODSSusceptibilities to the ethanolic extract of propolis against Streptococcus mutans (S. mutans), Streptococcus sobrinus (S. sobrinus), Streptococcus sanguis (S. sanguis), Actinomyces viscosus (A. viscosus), and Actinomyces naeslundii (A. naeslundii) were analyzed by crystal violet stain method to determine the minimum biofilm eradication concentration (MBEC). The biofilm was initially cultivated for 24 h. Subsequently, the propolis groups with different concentration MBEC and initial pH 7.0 were cultured for 24 h. Moreover, the pH value was measured to evaluate the acid-producing ability of the tested plaque biofilm. The effects of propolis on the insoluble extracellular polysaccharide synthesis of S. mutans biofilm were evaluated by anthrone method.

RESULTSThe MBEC of Yili propolis on S. mutans, S. sobrinus, S. sanguis, A. viscosus, and A. naeslundii were 6.25, 1.56, 3.13, 0.78, and 0.78 mg.mL-1, respectively. Propolis could decrease the ΔpH of the tested plaque biofilm, and the differences between the control and propolis groups were statistically significant (P<0.05). At MBEC, propolis could reduce the ability of S. mutans in synthesizing insoluble extracellular polysaccharides.

CONCLUSIONYili propolis demonstrate remarkable eradicative effects on the cariogenic plaque biofilm, showing inhibition of the synthesis of biofilm-produced acids and insoluble extracellular polysaccharides.

PURPOSE: Pneumonia is rather common and benign disease in children but its course is various. Many clinicians used the empirical antibiotics to treat pneumonia without identification of causative organism. This study was performed to find the pathogenic organism from the fluid culture by bronchoscopy with BAL (bronchoalveolar lavage) in severe pneumonia patients. METHODS: We studied 21 cases (male 15, female 6) who were admitted with severe pneumonia in the Department of Pediatrics, Sunlin Hospital from March to October in 1999. These patients had no underlying disease such as immunologic deficiency. We took laboratory tests including CBC, CRP, ESR, PB smear, mycoplasmal antibody and blood culture at admission day. We performed bronchoscopy with BAL, and wet smear and culture of that fluid. RESULTS: Organisms were cultured in nineteen cases out of 21 cases. Seven cases of Streptococcus mitis, five of Stenotrphomonas maltophilia, five cases of Streptococcus oralis, two of Moraxella species, two of Acinetobacter junii, one of Acinetobacter spesies, one Staphylococcus hominus, one alpha-h-Streptococcus, one Klebsiella pneumoniae, one Pseudomonas aeruginosa, one Enterobacter cloacae. Two organisms were cultured in nine cases. CONCLUSION: The positive rate of BALF culture was very high (90.5%). But, further studies are necessary for the patients with severe pneumonia preceded the use of antibiotics.
Acinetobacter ; Anti-Bacterial Agents ; Bronchoalveolar Lavage* ; Bronchoscopy ; Child ; Enterobacter cloacae ; Female ; Humans ; Klebsiella pneumoniae ; Moraxella ; Pediatrics ; Pneumonia* ; Pseudomonas aeruginosa ; Staphylococcus ; Streptococcus mitis ; Streptococcus oralis