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Molecules (Basel, Switzerland) Jan 2011Six pimarane-type diterpenes isolated from Viguiera arenaria Baker and two semi-synthetic derivatives were evaluated in vitro against a panel of representative...
Six pimarane-type diterpenes isolated from Viguiera arenaria Baker and two semi-synthetic derivatives were evaluated in vitro against a panel of representative microorganisms responsible for dental root canal infections. The microdilution method was used for the determination of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against Porphyromonas gingivalis, Prevotella nigrescens, Prevotella intermedia, Prevotella buccae, Fusobacterium nucleatum, Bacteroides fragilis, Actinomyces naeslundii, Actinomyces viscosus, Peptostreptococcus micros, Enterococcus faecalis and Aggregatibacter actinomycetemcomitans. The compounds ent-pimara-8(14),15-dien-19-oic acid, its sodium salt and ent-8(14),15-pimaradien-3β-ol were the most active, displaying MIC values ranging from 1 to 10 μg mL-1. The results also allow us to conclude that minor structural differences among these diterpenes significantly influence their antimicrobial activity, bringing new perspectives to the discovery of new chemicals for use as a complement to instrumental endodontic procedures.
Topics: Anti-Bacterial Agents; Bacteria; Diterpenes; Magnetic Resonance Spectroscopy; Microbial Sensitivity Tests; Mouth
PubMed: 21233793
DOI: 10.3390/molecules160100543 -
Journal of Periodontology Jan 2010Odontogenic infections are polymicrobial. This study explores the in vitro killing activity by concentrations similar to those found in crevicular fluid of tinidazole in... (Comparative Study)
Comparative Study
In vitro killing activity of crevicular concentrations of tinidazole plus common oral antibiotics against high-density mixed inocula of periodontal pathogens in strict anaerobic conditions.
BACKGROUND
Odontogenic infections are polymicrobial. This study explores the in vitro killing activity by concentrations similar to those found in crevicular fluid of tinidazole in combination with amoxicillin/clavulanic acid, clindamycin and levofloxacin against four groups of high-density mixed inocula of anaerobes (Prevotella buccae, Fusobacterium nucleatum, and Veillonella spp.) and facultative (Capnocytophaga spp. and Streptococcus spp.) isolates of periodontal pathogens.
METHODS
Killing curves were assessed under strict anaerobic conditions with antibiotics alone and in combination with tinidazole at concentrations similar to those achieved in crevicular fluid against approximately 10(7) colony forming units (CFU)/ml inoculum (1:1:1:1:1 proportion of the five bacterial isolates) of the four bacterial groups. Group 1 did not include beta-lactamase-producing strains; groups 2, 3, and 4 included one, two, and three beta-lactamase-producing strains, respectively.
RESULTS
In single-drug experiments, at 48 hours, tinidazole alone did not show significant killing of the entire bacterial population, whereas reductions in the initial inocula > or =2.09 log(10) CFU/ml with clindamycin, > or =3.26 log(10) CFU/ml with amoxicillin/clavulanic acid, and > or =3.83 log(10) CFU/ml with levofloxacin were obtained. When combined with tinidazole, reductions were significantly higher for all antibiotics: > or =5.28 log(10) CFU/ml with clindamycin, > or =4.78 log(10) CFU/ml with amoxicillin/clavulanic acid, and > or =6.17 log(10) CFU/ml with levofloxacin.
CONCLUSION
In addition to its high activity against anaerobic periodontal pathogens, tinidazole offered synergism with other antibiotics against the large strict anaerobic subpopulation and the small facultative subpopulation of a high-density mixed inocula of odontogenic pathogens under strict anaerobic conditions, similar to those of odontogenic infections.
Topics: Amoxicillin; Anti-Bacterial Agents; Bacteria, Anaerobic; Clavulanic Acid; Clindamycin; Drug Synergism; Drug Therapy, Combination; Gingival Crevicular Fluid; Humans; Levofloxacin; Microbial Sensitivity Tests; Microbial Viability; Ofloxacin; Periodontal Diseases; Tinidazole
PubMed: 20059425
DOI: 10.1902/jop.2009.090409 -
International Journal of Antimicrobial... May 2009The in vitro activity of tinidazole against anaerobic periodontal pathogens (25 Prevotella buccae, 18 Prevotella denticola, 10 Prevotella intermedia, 6 Prevotella...
The in vitro activity of tinidazole against anaerobic periodontal pathogens (25 Prevotella buccae, 18 Prevotella denticola, 10 Prevotella intermedia, 6 Prevotella melaninogenica, 5 Prevotella oralis, 10 Fusobacterium nucleatum and 8 Veillonella spp.) was determined by agar dilution. MIC(90) values (minimum inhibitory concentration for 90% of the organisms) were 8 microg/mL for Veillonella spp., 4 microg/mL for P. intermedia, 2 microg/mL for P. buccae, 1 microg/mL for Fusobacterium spp. and 0.5 microg/mL for other Prevotella spp. Cidal activity was studied by killing curves with tinidazole and amoxicillin (alone and in combination) at concentrations similar to those achieved in crevicular fluid (41.2 microg/mL tinidazole and 14.05 microg/mL amoxicillin) against an inoculum of ca. 10(7)colony-forming units/mL of four bacterial groups, each one composed of four different strains of the following periodontal isolates: Prevotella spp., Fusobacterium spp. and Veillonella spp. (anaerobes) and one amoxicillin-susceptible Streptococcus spp. (facultative) in a proportion of 1:1:1:1. When only beta-lactamase-negative Prevotella or Fusobacterium strains were tested, significantly higher reductions were found with amoxicillin (>4 log reduction at 48 h) versus controls. The presence of beta-lactamase-positive Prevotella spp. or F. nucleatum strains rendered amoxicillin inactive (no reductions at 48 h), with no differences from controls. Amoxicillin+tinidazole produced >3 log reduction at 24h and >4 log reduction at 48 h regardless of the presence or not of beta-lactamase-positive strains. The presence in crevicular fluid of beta-lactamases produced by beta-lactamase-positive periodontal pathogens may have ecological and therapeutic consequences since it may protect beta-lactamase-negative periodontal pathogens from amoxicillin treatment. In vitro, tinidazole offered high antianaerobic activity against beta-lactamase-positive and -negative periodontal pathogens, avoiding amoxicillin inactivation.
Topics: Amoxicillin; Anti-Bacterial Agents; Bacteria, Anaerobic; Bacterial Proteins; Fusobacterium; Humans; Microbial Sensitivity Tests; Microbial Viability; Periodontal Diseases; Prevotella; Streptococcus; Tinidazole; Veillonella; beta-Lactam Resistance; beta-Lactamases
PubMed: 19097755
DOI: 10.1016/j.ijantimicag.2008.10.012 -
Revista Espanola de Quimioterapia :... Mar 2007Resistance in streptococci or Gram-negative bacteria is associated with antibiotic consumption. Scarce information exists on the antibiotic susceptibility of bacterial...
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 susceptibility of bacterial isolates in periodontitis to antibiotics prescribed in odontology in Spain as treatment for local infections or prophylaxis for distant focal infections. Periodontal samples were prospectively collected in 48 patients classified by pocket depth of <4 mm and >or=4 mm. Species were identified by culture, selecting the five most frequent morphotypes per sample, and polymerase chain reaction (PCR). Susceptibility was determined by E-test. A total of 261 isolates were identified: 72.9% patients had Streptococcus oralis; 70.8% Streptococcus mitis; 60.4% Prevotella buccae; 39.6% Prevotella denticola; 37.5% Fusobacterium nucleatum; 35.4% Prevotella intermedia; 25% Capnocytophaga spp.; 23% Veillonella spp.; 22.9% Prevotella melaninogenica and Streptococcus sanguis; and <20% other species. Streptococcus viridans resistance rates were 0% for amoxicillin, approximately 10% for clindamycin, 9-22% for tetracycline, and for azithromycin ranged from 18.2% for S. sanguis to 47.7% for S. mitis. Prevotella isolates were susceptible to amoxicillin-clavulanic acid, with amoxicillin resistance ranging from 17.1% in P. buccae to 26.3% in P. denticola. Metronidazole resistance was <6% in all Prevotella species, while clindamycin resistance ranged from 0 to 21.1%. beta-Lactamase production was positive in 54.1% Prevotella spp., 38.9% F. nucleatum, 30% Capnocytophaga spp., and 10% Veillonella spp. In this study, amoxicillin-clavulanic acid was the most active antibiotic against all species tested, followed by metronidazole in the case of anaerobes.
Topics: Adult; Aged; Anti-Bacterial Agents; Bacteria; Drug Resistance, Bacterial; Drug Utilization; Female; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Periodontal Diseases; Reverse Transcriptase Polymerase Chain Reaction; Spain; Streptococcus; beta-Lactamases
PubMed: 17530037
DOI: No ID Found -
Current Microbiology May 2006Prevotella intermedia and Prevotella nigrescens are often regarded as principal causes of acute dentoalveolar infection; however, other species within the genus are also...
Prevotella intermedia and Prevotella nigrescens are often regarded as principal causes of acute dentoalveolar infection; however, other species within the genus are also known to be associated with such infection. The aim of this study was to determine the in vitro proteolytic activity of these different Prevotella species that have been implicated with dentoalveolar infection. A total of 234 strains were obtained from pus specimens from dentoalveolar infection and from the plaque of healthy volunteers. Prevotella loescheii, Prevotella oralis, Prevotella melaninogenica, Prevotella buccae, and Prevotella denticola were all shown to have a proteolytic activity (8.5-10.5 x 10(-8) A-units) lower than that of P. intermedia and P. nigrescens (21.1-23.5 x 10(-8) A-units). In the case of P. loescheii, P. melaninogenica, and P. intermedia, the level of proteolytic activity for clinical strains was significantly (P < 0.05) higher than that recorded for commensal strains. Proteolytic activity for all species of Prevotella examined was inhibited by N-ethylmaleimide and phenymethylsulfonyl fluoride. This study suggests that Prevotella species associated with oral purulent infection produce cysteine and serine proteinases and that in certain species of Prevotella, the strains involved in infection exhibit higher proteolytic activity when compared with strains from healthy sites.
Topics: Bacteroidaceae Infections; Cysteine Endopeptidases; Humans; Periodontitis; Prevotella; Prevotella intermedia; Serine Endopeptidases
PubMed: 16586023
DOI: 10.1007/s00284-005-0261-1 -
International Journal of Systematic and... Mar 2006Eight strains of anaerobic Gram-negative bacilli isolated from infections of the skin and soft tissues were subjected to a comprehensive range of phenotypic and...
Eight strains of anaerobic Gram-negative bacilli isolated from infections of the skin and soft tissues were subjected to a comprehensive range of phenotypic and genotypic tests. 16S rRNA gene sequence analysis revealed the strains to constitute a homogeneous group, distinct from species with validly published names but related to a cluster including Prevotella buccae, Prevotella dentalis and Prevotella baroniae. A novel species, Prevotella bergensis sp. nov., is proposed to accommodate these strains. Prevotella bergensis is saccharolytic and produces acetic and succinic acids as end products of fermentation. The G + C content of the DNA of the type strain is 48 mol%. The type strain of Prevotella bergensis is 94067913T (= DSM 17361T = CCUG 51224T).
Topics: DNA, Ribosomal; Fatty Acids; Humans; Nucleic Acid Hybridization; Phenotype; Phylogeny; Prevotella; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Skin Diseases, Bacterial; Soft Tissue Infections
PubMed: 16514036
DOI: 10.1099/ijs.0.63888-0 -
Comparative Immunology, Microbiology... Mar 2004Skin and soft-tissue infections in intravenous users comprise a variety of microorganisms and anaerobic bacteria are frequently involved in these suppurative infections....
Skin and soft-tissue infections in intravenous users comprise a variety of microorganisms and anaerobic bacteria are frequently involved in these suppurative infections. A case of subcutaneous abscess into anterior femoral muscles involving Actinomyces odontolyticus and two Prevotella species (Prevotella buccae and Prevotella melaninogenica) in an intravenous drug abuser is presented. This combination of microorganisms has not previously been described in soft-tissue infections. The patient volunteering that he licked his hypodermic needle prior to cocaine injection supports that the implicating bacteria originated from the oral cavity. Eventually, the patient recovered and at a 6-month follow-up a gradual improvement of his subcutaneous infection was noticed.
Topics: Abscess; Actinomyces; Actinomycosis; Adult; Bacteroidaceae Infections; Humans; Male; Prevotella melaninogenica; Soft Tissue Infections; Substance-Related Disorders
PubMed: 14690717
DOI: 10.1016/S0147-9571(03)00052-3 -
Journal of Applied Microbiology 2003(i) To compare the effects of feeding protocols upon the composition and stability of dental plaque microcosms formed in constant-depth film fermenters (CDFF). (ii) To...
AIMS
(i) To compare the effects of feeding protocols upon the composition and stability of dental plaque microcosms formed in constant-depth film fermenters (CDFF). (ii) To evaluate the utility of denaturing gradient gel electrophoresis (DGGE) and culture methodologies for the investigation of such models.
METHODS AND RESULTS
Microcosms were established anaerobically in the CDFFs from freshly collected saliva. These were fed either with artificial saliva alone (famine) or combined with discontinuous feeding (feast-famine). Culture and 16s rDNA sequencing indicated that supplemental feeding gave ca. 2 log increases in Lactobacillus rhamnosus and Prevotella buccae. Feast-famine microcosms were then further characterized by DGGE using primers specific for the V2-V3 region of eubacterial rDNA. These gave single major bands with pure cultures (eight species) and resolved all strains apart from Lact. rhamnosus and Actinomyces naeslundii. Whilst culture with selective media indicated a degree of stability and reproducibility between replicate microcosms, DGGE showed a considerable degree of variability that related to several putatively uncultured bacteria.
CONCLUSIONS
Feast-famine regimes altered community composition. DGGE analyses identified putatively unculturable species and demonstrated variability between replicate fermenters.
SIGNIFICANCE AND IMPACT OF THE STUDY
This study demonstrates the utility of DGGE for the analysis of dental plaque, especially with respect to unculturable bacteria. Results question the assumptions of reproducibility of plaque microcosms established in non-replicated CDFFs made on the basis of selective media. Feeding regimes, particularly those involving complex nutrients, will dramatically affect population dynamics.
Topics: Bacteria; Bacterial Typing Techniques; Base Sequence; Biofilms; Culture Media; DNA, Bacterial; DNA, Ribosomal; Dental Plaque; Ecosystem; Electrophoresis, Agar Gel; Humans; Models, Biological; Molecular Sequence Data; Polymerase Chain Reaction; RNA, Ribosomal, 16S; Saliva
PubMed: 12631201
DOI: 10.1046/j.1365-2672.2003.01876.x -
The Journal of Veterinary Medical... Oct 2000A retrobulbar abscess/cellulitis occurred in a Yorkshire Terrier dog. The clinical signs were exophthalmos, prolapsed nictitating membrane and purulent ocular discharge....
A retrobulbar abscess/cellulitis occurred in a Yorkshire Terrier dog. The clinical signs were exophthalmos, prolapsed nictitating membrane and purulent ocular discharge. Ultrasonography showed a marked soft tissue swelling of the retrobulbar tissues as well as echogenic parallel lines between the globe and the medial orbital rim. Surgical exploration of the orbit was performed and no foreign body was found. The pterygopalatine fossa was incised and therapeutic retrobulbar drainage attempted. A drain was placed to encourage ventral drainage of the abscess. Anaerobic cultures revealed heavy growth of gram negative rods (prevotella bivia and prevotella buccae were isolated). Recovery was successful but subsequent treatment for keratoconjunctivitis sicca was necessary. A full recovery of tear production occurred after several weeks.
Topics: Abscess; Anaerobiosis; Animals; Bacteroidaceae Infections; Cellulitis; Dog Diseases; Dogs; Male; Orbital Diseases; Prevotella; Ultrasonography
PubMed: 11073084
DOI: 10.1292/jvms.62.1105 -
Oral Microbiology and Immunology Dec 1999In a prospective study, 47 adults presenting a rapidly progressive periodontitis were selected in order to evaluate the prevalence of beta-lactamase-producing strains...
In a prospective study, 47 adults presenting a rapidly progressive periodontitis were selected in order to evaluate the prevalence of beta-lactamase-producing strains among oral anaerobic gram-negative rods. Predominant anaerobes were identified from two of the deepest periodontal pockets. beta-Lactamase-positive strains fulfilled to at least two of three criteria: positive nitrocefin test, penicillin Etest minimal inhibitory concentration > 1 microgram/ml, and disk diffusion synergy between amoxycillin and clavulanic acid > 10 mm. At least one beta-lactamase-producing strain was found in 53.2% of patients and 39.4% of the periodontal pockets investigated. Prominent beta-lactamase-positive species were Prevotella buccae and Prevotella intermedia (respectively 16 of 38: 42% and 18 of 52: 35% positive strains), followed by Prevotella bivia, Prevotella disiens, Prevotella denticola and Fusobacterium nucleatum (respectively 1 of 6: 17%, 1 of 10: 10%, 1 of 10: 10%, and 1 of 13: 8% positive strains). No beta-lactamase producer could be evidenced in Porphyromonas gingivalis (10 strains tested). All the beta-lactamase-positive strains with the nitrocefin test had penicillin minimal inhibitory concentrations > 1 microgram/ml with the Etest, and a strong synergy between amoxicillin and clavulanic acid was always observed.
Topics: Adult; Bacterial Proteins; Fusobacterium nucleatum; Gram-Negative Anaerobic Straight, Curved, and Helical Rods; Humans; Microbial Sensitivity Tests; Penicillin Resistance; Periodontal Pocket; Prevotella; Prospective Studies; beta-Lactamases
PubMed: 10895690
DOI: 10.1034/j.1399-302x.1999.140604.x