Home About us Contact
|
Home About us Contact | ||
|
|
||
MIC Range (mic + range)
Selected AbstractsSynthesis and in vitro antibacterial evaluation of 1-substituted-4-ethoxycarbonylmethylthiosemicarbazides and products of their dehydrocyclizationHETEROATOM CHEMISTRY, Issue 3 2010Agata Siwek A series of s -triazoles and thiohydantoines were synthesized by dehydrocyclization of 1-substituted-4-ethoxycarbonylmethylthiosemicarbazides. The molecular structure proposed for s -triazoles was confirmed by the X-ray crystal structure analysis of one compound that was prone to crystallization. All compounds were tested in vitro for their antibacterial activity. Some of them showed low levels of activity against Gram-positive species, MIC range 100,400 ,g/mL or higher. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:131,138, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20597 [source] Investigation of the interactions between neutrophils and endodontic isolates of Enterococcus faecalisINTERNATIONAL ENDODONTIC JOURNAL, Issue 4 2010R. Sairafi Aim, The primary aim of this study was to investigate the effect of phagocytosis by neutrophils on the antimicrobial sensitivity of Enterococcus faecalis strains. A secondary aim was to determine whether carriage of a plasmid encoding aggregation substance (AS), which has been reported to increase the survival of some strains inside neutrophils, affected the antimicrobial susceptibility of E. faecalis after phagocytosis by neutrophils. Methodology, An assay was carried out to identify isolates of E. faecalis which demonstrated pheromone-responsive clumping caused by the production of aggregation substance (AS). Four E. faecalis strains grown to both logarithmic and stationary phases were exposed to sodium hypochlorite (NaOCl) and chlorhexidine gluconate (CHX) to determine the minimum inhibitory concentrations of these two agents. The antimicrobial susceptibility tests were repeated with E. faecalis strains which survived phagocytosis by neutrophils for 18 h. Results, As expected a laboratory strain of E. faecalis OG1RF which was AS negative became AS positive after introduction of the pheromone responsive plasmid pCF10 into the bacterium to give strain OG1RF(pCF10). These two strains and two endodontic isolates, E08-584 which demonstrated pheromone-responsive clumping and E08-398 which did not, were selected for further study All the test E. faecalis strains were inhibited by low concentrations of sodium hypochlorite (MIC range 0.02,0.3%) and chlorhexidine gluconate (MIC range 0.0004,0.004%). Bacteria recovered from inside neutrophils after 18 h following phagocytosis were susceptible to both ¼MIC and MIC of CHX and NaOCl. Conclusions, Aggregation substance did not appear to affect the antimicrobial susceptibility of any of the strains to CHX or NaOCl. All of the E. faecalis strains examined were capable of survival for 18 h inside the neutrophils following phagocytosis; regardless of their capacity to produce aggregation substance. In addition, all strains of E. faecalis had enhanced susceptibilities to the antimicrobial agents after residence inside neutrophils for 18 h. [source] A selective broth enrichment combined with real-time nuc-mecA -PCR in the exclusion of MRSAAPMIS, Issue 1 2010TANJA PASANEN Pasanen T, Korkeila M, Mero S, Tarkka E, Piiparinen H, Vuopio-Varkila J, Vaara M, Tissari P. A selective broth enrichment combined with real-time nuc-mecA -PCR in the exclusion of MRSA. APMIS 2010; 118: 74,80. We analyzed the performance of a selective enrichment broth combined with Taqman-based real-time duplex nuc-mecA -PCR to expedite the screening of methicillin-resistant Staphylococcus aureus (MRSA). We found the broth to be able to select MRSA strains (oxacillin MIC range 4,256 ,g/ml) from MSSA strains. A total of 31 MRSA strains were found from 1250 clinical samples screened. The nuc-mecA -PCR was positive from all enrichment broths containing MRSA. From the remaining 1219 samples negative for MRSA on culture/subculture, 138 samples were nuc+/mecA+ in PCR. The sensitivity of the test was 93.5%, specificity 88.6%, positive predictive value 17.3%, and negative predictive value 99.8% as compared to culture. Thus, with this method, the negative MRSA results can be reliably reported within 24,48 h from sampling. The method is a practical additional alternative to those already described for the same purpose. [source] Ceragenin CSA-13 exhibits antimicrobial activity against cariogenic and periodontopathic bacteriaMOLECULAR ORAL MICROBIOLOGY, Issue 2 2009E. Isogai Introduction:, Ceragenin CSA-13 is a bile-acid-based mimic of endogenous antimicrobial peptides and shares a mechanism of action with many of these antimicrobial agents. Because CSA-13 is not peptide based, it is not a substrate for the proteases that are found in the oral cavity, which are capable of degrading antimicrobial peptides. Furthermore, the simplicity of the ceragenins makes them easier to prepare and purify than antimicrobial peptides. In this study, we examined the antimicrobial activities of CSA-13 against oral pathogens and found that this compound was bactericidal against all of the strains tested. Methods:, The strains used were isolates of Streptococcus mutans and Porphyromonas species. Minimum inhibitory concentrations (MIC) were determined using agar dilution methods. In susceptibility testing, viable counts were determined after incubation with CSA-13. Results:, CSA-13 was potent against all 23 strains tested with MICs of 1,8 ,g/ml for S. mutans and 1,16 ,g/ml for 24 strains of the genus Porphyromonas. The MIC50 was 2 and the MIC90 was 8 ,g/ml for S. mutans. MIC ranges for protease-positive P. gingivalis and P. cangingivaliswere 2,16 ,g/ml, and 1,2 ,g/ml for protease-negative P. circumdentaria. CSA-13 interacted with lipopolysaccharide-sensitized erythrocytes at a concentration of 5.0,20.0 ,g/ml. Conclusion:, CSA-13 displays broad-spectrum activity against cariogenic and periodontopathic bacteria. CSA-13 was effective against protease-positive Porphyromonas. It was shown to bind to erythrocytes coated with lipopolysaccharide and lipoteichoic acid from diverse bacterial strains. These results suggest that CSA-13 may be useful for the prevention and treatment of oral microbial diseases. [source] Antifungal activity of Heterothalamus alienus metabolitesPHYTOTHERAPY RESEARCH, Issue 4 2008Adriana del V. Pacciaroni Abstract The chemical study of Heterothalamus alienus gave rutin, spathulenol (1), (1R,7S)-germacra-4(15),5,10(14)-trien-1, -ol (2), sakuranetin (3), padmatin 3-acetate (4), (2R,3R)-dihydroquercetin-7,3,,4,-trimethyl ether (5), (2R,3R)-dihydroquercetin-7,4,-dimethyl ether (6), (2R,3R)-3-acetoxy-5,7,4,-trihydroxyflavanone (7), as the main components of an antifungal extract of the aerial parts of the plant. Compound 2 showed moderate activity, with Epidermophyton floccosum being the most susceptible species (MIC = 100 µg/mL); compound 3 showed the best antifungal behavior having a broad spectrum of action and the lowest MICs. This flavanone along with flavanolol 5 showed very good activity against standardized (MIC = 31.2 µg/mL) as well as clinical isolates of Trichophyton rubrum and T. mentagrophytes (MIC ranges 31.2,62.5 µg/mL and 31.2,125 µg/mL, respectively) and demonstrated not only fungistatic but also fungicide properties. Flavanolol 6 was active against all the dermatophytes tested with MICs of 62.5,250 µg/mL. Rutin, spathulenol (1) and the 3-acetylated flavanones 4 and 7 were inactive or marginally active against the fungal panel. Copyright © 2008 John Wiley & Sons, Ltd. [source] Antifungal activity of Mahonia aquifolium extract and its major protoberberine alkaloidsPHYTOTHERAPY RESEARCH, Issue 7 2003Anna Volleková Abstract The crude extract of Mahonia aquifolium (Berberidaceae) stem bark and its components berberine, palmatine and jatrorrhizine were screened for their inhibitory activity against a variety of dermatophytes and two Candida species of human origin using the in vitro dilution agar plate method. Jatrorrhizine was found to be the most effective against all fungal species tested (MIC ranges from 62.5 to 125 µg/mL), while the crude extract, berberine, and palmatine exhibited only marginal activity (MIC 500 to , 1000 µg/mL). Dermatophytes were more susceptible to jatrorrhizine than yeasts, and Scopulariopsis brevicaulis appeared the least sensitive species to all the compounds tested. The effects of the alkaloids were compared with those of .uconazole and bifonazole for which the MIC ranges were 12.5 to >100 µg/mL. Our results suggest that jatrorrhizine may serve as a leading compound for further studies to develop new antifungal agents with highly potent antifungal activity and low host toxicity. Copyright © 2003 John Wiley & Sons, Ltd. [source] | ||||||||||