| 1. |
- Alexeyev, O. A., et al.
(författare)
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Sampling and detection of skin Propionibacterium acnes : Current status
- 2012
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Ingår i: Anaerobe. - : Elsevier BV. - 1075-9964 .- 1095-8274. ; 18:5, s. 479-483
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Forskningsöversikt (refereegranskat)abstract
- A connection between acne vulgaris and Propionibacterium acnes has long been suggested. Over the years, several human skin microbiota sampling methods have been evolved and applied, e.g. swab, scrape, extraction techniques including cyanoacrylate gel sampling as well as punch biopsy. Collected samples have been processed following various methodologies ranging from culture studies to probe labelling and molecular analysis. Direct visualization techniques have recently shown the existence of anatomically distinct skin P acnes populations: epidermal and follicular. P. acnes biofilms appear to be a common phenomenon. Current sampling approaches target different skin populations of P. acnes and the presence of microbial biofilms can influence the retrieval of P. acnes. The anatomical considerations must be taken into account while interpreting microbiological data. (C) 2012 Elsevier Ltd. All rights reserved.
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| 2. |
- Ambalam, Padma, et al.
(författare)
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In vitro Mutagen binding and antimutagenic activity of human Lactobacillus rhamnosus 231
- 2011
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Ingår i: Anaerobe. - : Elsevier BV. - 1095-8274 .- 1075-9964. ; 17:5, s. 217-222
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Tidskriftsartikel (refereegranskat)abstract
- In vitro mutagen binding ability of human Lactobacillus rhamnosus 231 (Lr 231) was evaluated against acridine orange (AO), N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), 2-amino-3, 8-dimethylimidazo[4,5-f]-quinoxaline (MeIQx) and 4-nitro-o-phenylenediamine (NPD). Binding of AO by Lr 231 is due to adsorption, thereby leading to removal of mutagen in solution and is instantaneous, pH- and concentration-dependent. Whereas, binding of MNNG and MeIQx by Lr 231 results into biotransformation leading to detoxification with subsequent loss of mutagenicity as determined by spectral analysis, thin layer chromatography and Ames test. Binding of mutagen by Lr 231 was dependent on culture age and optimum binding of AO, MNNG and MeIQx was observed to occur with 24 h old culture. Cells of Lr 231 were subjected to different chemical treatments prior to binding studies. Results indicated cell wall component such as cell wall polysaccharide, peptidoglycan, carbohydrates and proteins plays an important role in adsorption of AO, also involving hydrophilic and ionic interactions. Binding, biotransformation and detoxification of MNNG and MeIQx by Lr 231 was dependent on cell surface characteristics mainly involving carbohydrates, proteins, teichoic acid/lipoteichoic acid, hydrophobic interaction and presence of thiol group. L rhamnosus 231 bound MNNG instantaneously. More than 96 (p < 0.01) and 70% (p < 0.05) cells remained viable after mutagen binding and various pretreatments respectively. This study shows Lr 231 exhibits ability to bind and detoxify potent mutagens, and this property can be useful in formulating fermented foods for removal of potent mutagens. (C) 2011 Elsevier Ltd. All rights reserved.
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| 3. |
- Basic, Amina, et al.
(författare)
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Hydrogen sulfide production from subgingival plaque samples.
- 2015
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Ingår i: Anaerobe. - : Elsevier BV. - 1095-8274 .- 1075-9964. ; 35:Part A, s. 21-27
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Tidskriftsartikel (refereegranskat)abstract
- Periodontitis is a polymicrobial anaerobe infection. Little is known about the dysbiotic microbiota and the role of bacterial metabolites in the disease process. It is suggested that the production of certain waste products in the proteolytic metabolism may work as markers for disease severity. Hydrogen sulfide (H2S) is a gas produced by degradation of proteins in the subgingival pocket. It is highly toxic and believed to have pro-inflammatory properties. We aimed to study H2S production from subgingival plaque samples in relation to disease severity in subjects with natural development of the disease, using a colorimetric method based on bismuth precipitation. In remote areas of northern Thailand, adults with poor oral hygiene habits and a natural development of periodontal disease were examined for their oral health status. H2S production was measured with the bismuth method and subgingival plaque samples were analyzed for the presence of 20 bacterial species with the checkerboard DNA-DNA hybridization technique. In total, 43 subjects were examined (age 40-60 years, mean PI 95±6.6%). Fifty-six percent had moderate periodontal breakdown (CAL>3<7mm) and 35% had severe periodontal breakdown (CAL>7mm) on at least one site. Parvimonas micra, Filifactor alocis, Porphyromonas endodontalis and Fusobacterium nucleatum were frequently detected. H2S production could not be correlated to periodontal disease severity (PPD or CAL at sampled sites) or to a specific bacterial composition. Site 21 had statistically lower production of H2S (p=0.02) compared to 16 and 46. Betel nut chewers had statistically significant lower H2S production (p=0.01) than non-chewers. Rapid detection and estimation of subgingival H2S production capacity was easily and reliably tested by the colorimetric bismuth sulfide precipitation method. H2S may be a valuable clinical marker for degradation of proteins in the subgingival pocket.
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| 4. |
- Bronnec, Vicky, et al.
(författare)
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In vivo model of Propionibacterium (Cutibacterium) spp. biofilm in Drosophila melanogaster
- 2021
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Ingår i: Anaerobe. - : Academic Press. - 1075-9964 .- 1095-8274. ; 72
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: Acne vulgaris is a common inflammatory disorder of the pilosebaceous unit and Propionibacterium acnes biofilm-forming ability is believed to be a contributing factor to the disease development. In vivo models mimicking hair follicle environment are lacking. The aim of this study was to develop an in vivo Propionibacterium spp. biofilm model in Drosophila melanogaster (fruit fly).Methods: We created a sterile line of D. melanogaster able to sustain Propionibacterium spp. biofilms in the gut. In order to mimic the lipid-rich, anaerobic environment of the hair follicle, fruit flies were maintained on lipid-rich diet. Propionibacterium spp. biofilms were visualized by immunofluorescence and scanning electron microscopy. We further tested if the biofilm-dispersal activity of DNase I can be demonstrated in the developed model.Results: We have demonstrated the feasibility of our in vivo model for development and study of P. acnes, P. granulosum and P. avidum biofilms. The model is suitable to evaluate dispersal as well as other agents against P. acnes biofilm.Conclusions: We report a novel in vivo model for studying Propionibacterium spp. biofilms. The model can be suitable for both mechanistic as well as interventional studies.
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| 5. |
- Claesson, Rolf, et al.
(författare)
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Actinomyces radicidentis and Actinomyces haliotis, coccoid Actinomyces species isolated from the human oral cavity
- 2017
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Ingår i: Anaerobe. - : Elsevier. - 1075-9964 .- 1095-8274. ; 48, s. 19-26
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Tidskriftsartikel (refereegranskat)abstract
- There are few reports on the bacterial species Actinomyces radicidentis in the literature. In this study, putative A. radicidentis isolates were collected from 16 root canal samples from 601 examined patients. The isolates were examined by biochemical tests, 16S rRNA gene sequencing, Arbitrarily-primed (AP-) PCR, antibiotic susceptibility testing, and MALDI-TOF analyses. In parallel, two A. radicidentis reference strains and two putative A. radicidentis isolates from United Kingdom were tested. Sixteen of the 18 isolates were confirmed as A. radicidentis. The remaining two isolates, both of which were isolated from root canals (one from Sweden and the other from the UK), but were identified as Actinomyces haliotis by sequencing ∼ 1300 base pairs of the 16S rRNA-gene. This isolates had a divergent, but between them similar, AP-PCR pattern, and a common distribution of sequence signatures in the 16S rRNA gene, but were not identified by MALDI-TOF. A. haliotis is a close relative to A. radicidentis, hitherto only been described from a sea-snail. The identity of A. haliotis was confirmed by a phylogenetic tree based on 16S rRNA gene sequences with species specific sequences included, and by additional biochemical tests. The examined bacteria exhibited similar antibiotic susceptibility patterns when tested for 10 separate antibiotic classes with E-tests (bioMérieux). The MIC90 for β-lactams (benzylpenicillin and cefuroxime) and vancomycin was 0.5 mg/L, for colistin and ciprofloxacin 8 mg/mL and for the other antibiotic classes ≤ 25 mg/mL The isolation of A. haliotis from infected dental root canals cast doubt on the accepted opinion that all Actinomyces infections have an endogenous source.
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| 6. |
- Dahlén, Gunnar, 1944, et al.
(författare)
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Low antibiotic resistance among anaerobic Gram-negative bacteria in periodontitis 5 years following metronidazole therapy.
- 2017
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Ingår i: Anaerobe. - : Elsevier BV. - 1095-8274 .- 1075-9964. ; 43, s. 94-98
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Tidskriftsartikel (refereegranskat)abstract
- The objective of this study was to assess antibiotic susceptibility among predominant Gram-negative anaerobic bacteria isolated from periodontitis patients who 5 years prior had been subject to mechanical therapy with or without adjunctive metronidazole. One pooled sample was taken from the 5 deepest sites of each of 161 patients that completed the 5 year follow-up after therapy. The samples were analyzed by culture. A total number of 85 anaerobic strains were isolated from the predominant subgingival flora of 65/161 patient samples, identified, and tested for antibiotic susceptibility by MIC determination. E-tests against metronidazole, penicillin, amoxicillin, amoxicillin+clavulanic acid and clindamycin were employed. The 73/85 strains were Gram-negative rods (21 Porphyromonas spp., 22 Prevotella/Bacteroides spp., 23 Fusobacterium/Filifactor spp., 3 Campylobacter spp. and 4 Tannerella forsythia). These were all isolated from the treated patients irrespective of therapy procedures (+/-metronidazole) 5 years prior. Three strains (Bifidobacterium spp., Propionibacterium propionicum, Parvimonas micra) showed MIC values for metronidazole over the European Committee on Antimicrobial Susceptibility Testing break point of >4μg/mL. All Porphyromonas and Tannerella strains were highly susceptible. Metronidazole resistant Gram-negative strains were not found, while a few showed resistance against beta-lactam antibiotics. In this population of 161 patients who had been subject to mechanical periodontal therapy with or without adjunct metronidazole 5 years prior, no cultivable antibiotic resistant anaerobes were found in the predominant subgingival microbiota.
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| 7. |
- Dahlén, Gunnar, 1944, et al.
(författare)
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Oral microflora in betel-chewing adults of the Karen tribe in Thailand.
- 2010
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Ingår i: Anaerobe. - : Elsevier BV. - 1095-8274 .- 1075-9964. ; 16:4, s. 331-6
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To study a possible influence of betel chewing on the composition of the oral microflora in plaque and saliva and on oral health parameters as well as a possible betel effect on oral bacteria in vitro. MATERIAL AND METHODS: Thirty-two adults (16 betel chewers and 16 non-betel-chewing controls) of the Karen Hill tribe in Thailand were investigated. Saliva samples and 2 pooled supragingival plaque samples were taken from each individual for microbial analysis with culture and 4 subgingival samples for analysis with the DNA-DNA hybridization method against 12 periodontitis associated bacterial species. Caries (DMFS), plaque (PlI%) and bleeding on probing (% BoP) was registered as well as number of sites with >5mm probing pocket depth (PPD). Water extract of the betel (areca chatechu) nut was tested for its antimicrobial effect in vitro against 10 oral bacterial species with the agar diffusion method. RESULTS: An antimicrobial effect of betel nut water extract was found on the oral microorganisms in vitro. The levels of mutans streptococci and lactobacilli in saliva were low or absent in both chewers and controls. The prevalence of the periodontitis associated bacteria was >90%. Betel chewers had significantly lower levels of some bacteria in subgingival plaque (Prevotella intermedia p<0.001) than non-chewers. This study population was low in missing teeth (mean 0.7 and 0.3), caries decay (DS 2.1 vs 1.6), and number of deep pockets (mean 1.9 vs 1.3). Great variation in oral hygiene (PlI and BoP) between the subjects was seen. CONCLUSIONS: An antimicrobial effect of the betel nut was found in vitro and with a possible effect also in vivo; however it did not seem to influence clinical parameters such as plaque index, caries prevalence (DMFS), bleeding on probing and number of deep pockets.
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| 8. |
- D'Aimmo, Maria Rosaria, 1975, et al.
(författare)
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Biosynthesis and cellular content of folate in bifidobacteria across host species with different diets
- 2014
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Ingår i: Anaerobe. - : Elsevier BV. - 1095-8274 .- 1075-9964. ; 30, s. 169-177
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Tidskriftsartikel (refereegranskat)abstract
- Background: Bifidobacteria, one of the most common bacteria of the intestinal tract, help establish balance in the gut microbiota and confer health benefits to the host. One beneficial property is folate biosynthesis, which is dependent on species and strains. It is unclear whether the diversity in folate biosynthesis is due to the adaptation of the bifidobacteria to the host diet or whether it is related to the phylogeny of the animal host. To date, folate production has been studied in the bifidobacteria of omnivorous, and a few herbivorous, non-primate hosts and humans, but not in carnivores, non-human primates and insects. In our study we screened folate content and composition in bifidobacteria isolated from carnivores (dog and cheetah), Hominoidea omnivorous non-human primates (chimpanzee and orangutan) and nectarivorous insects (honey bee). Results: Bifidobacterium pseudolongum subsp. globosum, a species typically found in non-primates, was isolated from dog and cheetah, and Bifidobacterium adolescentis and Bifidobacterium dentium, species typically found in humans, were respectively obtained from orangutan and chimpanzee. Evidence of folate biosynthesis was found in bifidobacteria isolated from non-human primates, but not from the bifidobacteria of carnivores and honey-bee. On comparing species from different hosts, such as poultry and herbivorous/omnivorous non-primates, it would appear that folate production is characteristic of primate (human and non-human) bifidobacteria but not of non-primate. Isolates from orangutan and chimpanzee had a high total folate content, the mean values being 7792 mu g/100 g dry matter (DM) for chimpanzee and 8368 mu g/100 g DM for orangutan. The tetrahydrofolate (H(4)folate) and 5-niethyl-tetrahydrofolate (5-CH3-H(4)folate) distribution varied in the bifidobacteria of the different animal species, but remained similar in the strains of the same species: B. dentium CHZ9 contained the least 5-CH3-H(4)folate (3749 mu/100 g DM), while B. adolescentis ORG10 contained the most (8210 mu g/100 g DM). Conclusion: Our data suggest a correlation between phylogenetic lineage and capacity of folate production by bifidobacteria, rather than with dietary type of the host.
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| 9. |
- Davidsson, Sabina, 1972-, et al.
(författare)
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Multilocus sequence typing and repetitive-sequence-based PCR (DiversiLab) for molecular epidemiological characterization of Propionibacterium acnes isolates of heterogeneous origin
- 2012
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Ingår i: Anaerobe. - : Elsevier. - 1075-9964 .- 1095-8274. ; 18:4, s. 392-399
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Tidskriftsartikel (refereegranskat)abstract
- Propionibacterium acnes is a gram-positive bacillus predominantly found on the skin. Although it is considered an opportunistic pathogen it is also been associated with severe infections. Some specific P. acnes subtypes are hypothesized to be more prone to cause infection than others. Thus, the aim of the present study was to investigate the ability to discriminate between P. acnes isolates of a refined multilocus sequence typing (MLST) method and a genotyping method, DiversiLab, based on repetitive-sequence-PCR technology.The MLST and DiversiLab analysis were performed on 29 P. acnes isolates of diverse origins; orthopedic implant infections, deep infections following cardiothoracic surgery, skin, and isolates from perioperative tissue samples from prostate cancer. Subtyping was based on recA, tly, and Tc12S sequences.The MLST analysis identified 23 sequence types and displayed a superior ability to discriminate P. acnes isolates compared to DiversiLab and the subtyping. The highest discriminatory index was found when using seven genes. DiversiLab was better able to differentiate the isolates compared to the MLST clonal complexes of sequence types.Our results suggest that DiversiLab can be useful as a rapid typing tool for initial discrimination of P. acnes isolates. When better discrimination is required, such as for investigations of the heterogeneity of P. acnes isolates and its involvement in different pathogenic processes, the present MLST protocol is valuable.
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| 10. |
- Fang, Hong, et al.
(författare)
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Effects of cefoxitin on the growth and morphology of Bacteroides thetaiotaomicron strains with different cefoxitin susceptibility
- 2002
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Ingår i: Anaerobe. - : Elsevier BV. - 1075-9964 .- 1095-8274. ; 8:2, s. 55-61
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Tidskriftsartikel (refereegranskat)abstract
- To examine the effects of cefoxitin on bacterial growth and cell morphology, two pairs of Bacteroides thetaiotaomicron strains (238, 238 m and 1186, 1186 m) with different susceptibilities to this antibiotic were investigated in the present study. B. thetaiotaomicron 238m and 1186m were resistant laboratory mutants originating from the susceptible wild-type strains B. thetaiotaomicron 238 and 1186, respectively. It has been shown, in a previous study, that the mutant strains had alterations in their penicillin-binding proteins (PBPs) as compared to the parent strains. In the present study, strains 238 and 238m presented almost identical genomic fingerprints by PCR, so did strains 1186 and 1186m, which indicates that the parent and mutant strains have similar genomic background. In comparison with the parent strains, the growth rate of mutant strains was slower in cultures without antibiotic. The growth patterns challenged with cefoxitin were also different between the parent and the mutant strains. In case of the morphological responses to cefoxitin, the mutant strains were more resistant to the effect of cefoxitin than the parent strains. In conclusion, the growth patterns and the morphological changes induced by cefoxitin, of the investigated strains, were associated with the properties of PBPs. The resistant mutants with deficiency in PBPs grew slower than the susceptible parent strains, and cefoxitin caused filamentation at sub-MIC in B. thetaiotaomicron.
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| 11. |
- Fang, Hong, et al.
(författare)
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Identification of the metallo-beta-lactamase gene from clinical isolates of Bacteroides fragilis
- 1999
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Ingår i: Anaerobe. - : Elsevier BV. - 1075-9964 .- 1095-8274. ; 5:3-4, s. 431-434
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Tidskriftsartikel (refereegranskat)abstract
- Bacteroides fragilis is one of the organisms known to produce carbapenem-hydrolysing metallo-beta-lactamase, which can confer resistance to a wide variety of beta-lactams. The purpose of this study was to identify carbapenem-hydrolysing metallo-beta-lactamase-producing B. fragilis strains by means of PCR assay, nucleotide sequencing and enzyme inhibition studies. Ten beta-lactam-resistant B. fragilis isolates were investigated. Four imipenem-resistant strains among the 10 isolates gave positive reactions in the PCR assay. The nucleotide sequences of the PCR products from two imipenem-resistant strains shared >98% similarity with the metallo-beta-lactamase gene from B. fragilis TAL 3636, which was used as a control. The amino acid sequence homology between the two imipenem-resistant strains and B. fragilis TAL 3636 was 99.2%. These strains produced high amounts of Zn2+-dependent beta-lactamases which were inactivated by EDTA.
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| 12. |
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| 13. |
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| 14. |
- Jahns, Anika C., et al.
(författare)
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Microbial colonization of normal skin : Direct visualization of 194 skin biopsies
- 2016
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Ingår i: Anaerobe. - : Elsevier BV. - 1075-9964 .- 1095-8274. ; 38, s. 47-49
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Tidskriftsartikel (refereegranskat)abstract
- Recent genetic studies have suggested the presence of numerous microbial species on and in the skin. We characterised microbial colonization of a large collection of skin biopsies from 194 healthy subjects by fluorescence assay. Forty per cent of all biopsies did not show any evidence for microbial colonization. Propionibacterium acnes was the sole predominant bacterial species in both sebaceous and non-sebaceous areas. Non- P. acnes species were present in approximately 30% of all colonized samples.. Only hair follicles and stratum corneum were colonized. Understanding of cutaneous microbiota requires validation from a variety of approaches and techniques.
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| 15. |
- Jahns, Anika C, et al.
(författare)
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Simultaneous visualization of Propionibacterium acnes and Propionibacterium granulosum with immunofluorescence and fluorescence in situ hybridization
- 2013
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Ingår i: Anaerobe. - : Elsevier. - 1075-9964 .- 1095-8274. ; 23, s. 48-54
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Tidskriftsartikel (refereegranskat)abstract
- Propionibacterium acnes (P. acnes) and Propionibacterium granulosum (P. granulosum) are common skin colonizers that are implicated as possible contributing factors in acne vulgaris development. We have established direct visualization tools for the simultaneous detection of these closely related species with immunofluorescence assay and fluorescence in situ hybridization (FISH). As proof of principle, we were able to distinguish P. acnes and P. granulosum bacteria in multi-species populations in vitro as well as in a mock skin infection model upon labelling with 16S rRNA probes in combinatorial FISH as well as with antibodies. Furthermore, we report the co-localization of P. acnes and P. granulosum in the stratum corneum and hair follicles from patients with acne vulgaris as well as in healthy individuals. Further studies on the spatial distribution of these bacteria in skin structures in various skin disorders are needed.
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| 16. |
- Jahns, Anika C., et al.
(författare)
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Transcriptomic analysis of Propionibacterium acnes biofilms in vitro
- 2016
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Ingår i: Anaerobe. - : Elsevier BV. - 1075-9964 .- 1095-8274. ; 42, s. 111-118
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Tidskriftsartikel (refereegranskat)abstract
- Propionibacterium acnes is a well-known commensal of the human skin connected to acne vulgaris and joint infections. It is extensively studied in planktonic cultures in the laboratory settings but occurs naturally in biofilms. In this study we have developed an in vitro biofilm model of P. acnes and studied growth features, matrix composition, matrix penetration by fluorescent-labeled antibiotics as well as gene expression. Antibiotic susceptibility of biofilms was studied and could be enhanced by increased glucose concentrations. Biofilm cells were characterized by up-regulated stress-induced genes and up regulation of genes coding for the potential virulence-associated CAMP factors. P. acnes can generate persister cells showing a reversible tolerance to 50 fold MIC of common antibiotics.
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| 17. |
- Karlsson, Anna, 1969-, et al.
(författare)
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Degradation of phenol under meso- and thermophilic, anaerobic conditions
- 1998
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Ingår i: Anaerobe. - : Elsevier BV. - 1075-9964 .- 1095-8274. ; 5:1, s. 25-35
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Tidskriftsartikel (refereegranskat)abstract
- Based on the results of preliminary studies on phenol degradation under mesophilic conditions with a mixed methanogenic culture, we proposed a degradation pathway in which phenol is fermented to acetate: Part of the phenol is reductively transformed to benzoate while the rest is oxidised, forming acetate as end product. According to our calculations, this should result in three moles of phenol being converted to two moles of benzoate and three moles of acetate (3phenol+2CO2+3H2O→3acetate+2benzoate): To assess the validity of our hypothesis concerning the metabolic pathway, we studied the transformation of phenol under mesophilic and thermophilic conditions in relation to the availability of hydrogen. Hence, methanogenic meso- and thermophilic cultures amended with phenol were run with or without an added over-pressure of hydrogen under methanogenic and non-methanogenic conditions. Bromoethanesulfonic acid (BES) was used to inhibit methanogenic activity. In the mesophilic treatments amended with only BES, about 70% of the carbon in the products found was benzoate. During the course of phenol transformation in these BES-amended cultures, the formation pattern of the degradation products changed: Initially nearly 90% of the carbon from phenol degradation was recovered as benzoate, whereas later in the incubation, in addition to benzoate formation, the aromatic nucleus degraded completely to acetate. Thus, the initial reduction of phenol to benzoate resulted in a lowering of H2levels, giving rise to conditions allowing the degradation of phenol to acetate as the end product. Product formation in bottles amended with BES and phenol occurred in accordance with the hypothesised pathway; however, the overall results indicate that the degradation of phenol in this system is more complex. During phenol transformation under thermophilic conditions, no benzoate was observed and no phenol was transformed in the BES-amended cultures. This suggests that the sensitivity of phenol transformation to an elevated partial pressure of H2is higher under thermophilic conditions than under mesophilic ones. The lack of benzoate formation could have been due to a high turnover of benzoate or to a difference in the phenol degradation pathway between the thermophilic and mesophilic cultures.
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| 18. |
- Khassebaf, Jasmine, et al.
(författare)
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Antibiotic susceptibility of Propionibacterium acnes isolated from orthopaedic implant-associated infections
- 2015
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Ingår i: Anaerobe. - : Elsevier. - 1075-9964 .- 1095-8274. ; 32, s. 57-62
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Prosthetic joint infections (PJIs) caused by Propionibacterium acnes account for a larger proportion of the total number of PJIs than previously assumed and thus knowledge of the antimicrobial susceptibility patterns of P. acnes is of great value in everyday clinical practice.Materials and methods: Using Etest, the present study investigated the susceptibility of 55 clinical isolates of P. acnes, obtained from orthopaedic implant-associated infections of the knee joint (n = 5), hip joint (n = 17), and shoulder joint (n = 33), to eight antimicrobial agents: benzylpenicillin, clindamycin, metronidazole, fusidic acid, doxycycline, moxifloxacin, linezolid and rifampicin. Synergy testing was also conducted, in which rifampicin was combined with each of the remaining seven antibiotics.Results: All isolates (n = 55) were susceptible to most of the antibiotics tested, with the exception of 100% resistance to metronidazole, five (9.1%) isolates displaying decreased susceptibility to clindamycin, and one (1.8%) to moxifloxacin. None of the antimicrobial agents investigated were synergistic with each other when combined and nine isolates were antagonistic for various antimicrobial combinations. The majority of the antimicrobial combinations had an indifferent effect on the isolates of P. acnes. However, the combination of rifampicin and benzylpenicillin showed an additive effect on nearly half of the isolates.Conclusion: Almost all P. acnes, isolated from orthopaedic implant-associated infections, predominantly PJIs, were susceptible to the antibiotics tested, with the exception of complete resistance to metronidazole. Synergy test could not demonstrate any synergistic effect but additive effects were found when combining various antibiotics. Antagonistic effects were rare.
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| 19. |
- Kondepudi, Kanthi Kiran, et al.
(författare)
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Prebiotic-non-digestible oligosaccharides preference of probiotic bifidobacteria and antimicrobial activity against Clostridium difficile.
- 2012
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Ingår i: Anaerobe. - : Elsevier BV. - 1095-8274 .- 1075-9964. ; 18:5, s. 489-497
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Tidskriftsartikel (refereegranskat)abstract
- Bifidobacterium breve 46, Bifidobacteriumlactis 8:8 and Bifidobacteriumlongum 6:18 and three reference strains B. breve CCUG 24611, B. lactis JCM 10602, and Bifidobacteriumpseudocatenulatum JCM 1200 were examined for acid and bile tolerance, prebiotic utilization and antimicrobial activity against four Clostridium difficile (CD) strains including the hypervirulent strain, PCR ribotype NAP1/027. B. lactis 8:8 and B. lactis JCM 10602 exhibited a high tolerance in MRSC broth with pH 2.5 for 30 min. B. breve 46 and B. lactis 8:8 remained 100% viable in MRSC broth with 5% porcine bile after 4 h. All six strains showed a high prebiotic degrading ability (prebiotic score) with galactooligosaccharides (GOS), isomaltooligosaccharides (IMOS) and lactulose as carbon sources and moderate degradation of fructooligosaccharides (FOS). Xylooligosaccharides (XOS) was metabolized to a greater extent by B. lactis 8:8, B. lactis JCM 10602, B. pseudocatenulatum JCM 1200 and B. longum 6:18 (prebiotic score >50%). All strains exhibited extracellular antimicrobial activity (AMA) against four CD strains including the CD NAP1/027. AMA of B. breve 46, B. lactis 8:8 and B. lactis JCM 10602 strains was mainly ascribed to a combined action of organic acids and heat stable, protease sensitive antimicrobial peptides when cells were grown in MRSC broth with glucose and by acids when grown with five different prebiotic-non-digestible oligosaccharides (NDOs). None of C. difficile strains degraded five prebiotic-NDOs. Whole cells of B. breve 46 and B. lactis 8:8 and their supernatants inhibited the growth and toxin production of the CD NAP1/027 strain.
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| 20. |
- Lawson, Paul A, et al.
(författare)
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Dysgonomonas hofstadii sp. nov., isolated from a human clinical source.
- 2010
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Ingår i: Anaerobe. - : Elsevier BV. - 1095-8274 .- 1075-9964. ; 16:2, s. 161-4
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Tidskriftsartikel (refereegranskat)abstract
- A Gram-negative staining, facultative anaerobic, cocco-bacillus-shaped organism was isolated from a post-operative abdominal wound. Based on morphological and biochemical criteria, strain MX 1040 (=CCUG 54731(T)) was tentatively identified as Bacteroidaceae but did not correspond to any recognized species of this family. Comparative 16S rRNA gene sequencing analysis demonstrated the organism to be related to species of the genus Dysgonomonas, although sequence divergence values of >5% with the other members of this genus demonstrated the organism to represent a novel species. Phylogenetic analysis revealed the novel organism to be most closely related to Dysgonomonas gadei. The major long-chain cellular fatty acids of the novel species consisted of iso-C(14:0), anteiso-C(15:0), C(16:0), and iso-C(16:0). Based on the phenotypic criteria and phylogenetic considerations, it is proposed that strain MX 1040 from a human clinical source represents a new species of the genus Dysgonomonas, as Dysgonomonas hofstadii sp. nov. The type strain of D. hofstadii is CCUG 54731(T) (=CCM 7606(T)).
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| 21. |
- Lawson, Paul A, et al.
(författare)
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Peptostreptococcus canis sp. nov., isolated from subgingival plaque from canine oral cavity.
- 2012
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Ingår i: Anaerobe. - : Elsevier BV. - 1095-8274 .- 1075-9964. ; 18:6, s. 597-601
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Tidskriftsartikel (refereegranskat)abstract
- A polyphasic taxonomic study was performed on two strains of an unknown Gram-positive, asaccharolytic, nonspore-forming, obligately anaerobic coccus-shaped bacterium isolated from oral subgingival plaque of Labrador retriever dogs. Comparative 16S rRNA gene sequencing confirmed that these isolates were highly related to each other and formed a hitherto unknown linage within the clostridial rRNA XI cluster of organisms. Pairwise analysis demonstrated that the novel organism to be most closely related to members of the genus Peptostreptococcus with 16S rDNA gene sequence similarity values between 92.8% and 96.7%, respectively. The G+C DNA base composition was 30.8mol% and the major cellular fatty acids included iso-C(14:0,) iso-C(16:0), and iso-C(16:0 DMA). Based on biochemical, chemotaxonomic, and phylogenetic evidence it is proposed that the unknown bacterium be classified as a new species, Peptostreptococcus canis sp. nov. The type strain is CCUG 57081(T).
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| 22. |
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| 23. |
- Liew-Littorin, C., et al.
(författare)
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Clonal diversity of Cutibacterium acnes (formerly Propionibacterium acnes) in prosthetic joint infections
- 2019
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Ingår i: Anaerobe. - : Elsevier. - 1075-9964 .- 1095-8274. ; 59, s. 54-60
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Tidskriftsartikel (refereegranskat)abstract
- Prosthetic joint infections (PJIs) are rare but feared complications following joint replacement surgery. Cutibacterium acnes is a skin commensal that is best known for its role in acne vulgaris but can also cause invasive infections such as PJIs. Some phylotypes might be associated with specific diseases, and recently, a plasmid was detected that might harbour important virulence genes. In this study, we characterized C. acnes isolates from 63 patients with PJIs (n=140 isolates) and from the skin of 56 healthy individuals (n=56 isolates), using molecular methods to determine the phylotype and investigate the presence of the plasmid. Single-locus sequence typing and a polymerase chain reaction designed to detect the plasmid were performed on all 196 isolates. No statistically significant differences in sequence types were seen between the two study groups indicating that the C. acnes that causes PJIs originates from the patients own normal skin microbiota. Of the 27 patients with multiple tissue samples, 19 displayed the same sequence types among all their samples. Single-locus sequence typing identified different genotypes among consecutive C. acnes isolates from four patients with recurrent infections. The plasmid was found among 17 isolates distributed in both groups, indicating that it might not be a marker for virulence regarding PJIs. Patients presenting multiple sequence types in tissue samples may represent contamination or a true polyclonal infection due to C. acnes.
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| 24. |
- Löfmark, Sonja, et al.
(författare)
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Restored fitness leads to long-term persistence of resistant Bacteroides strains in the human intestine
- 2008
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Ingår i: Anaerobe. - : Elsevier BV. - 1075-9964 .- 1095-8274. ; 14:3, s. 157-160
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Tidskriftsartikel (refereegranskat)abstract
- Acquired antibiotic resistance typically confers a cost to the bacteria, but these costs can be reduced by genetic compensation over time. The fitness of two Bacteroides thetaiotaomicron clones consecutively isolated in vivo was studied using an in vitro pair-wise competition method. The isolates derived from faecal samples of two clindamycin-exposed healthy volunteers and the two B. thetaiotaomicron clone types could be followed up to 18 months in these two subjects. The two clones were originally susceptible to clindamycin and lacked erm genes; however, after 7 days of clindamycin administration they carried the erm (erythromycin methylase)(G) or (F) gene, respectively, and expressed phenotypic clindamycin resistance. The initial cost of acquired resistance was high as seen in the in vitro pair-wise competition experiments. At 2 weeks post-administration, no growth disadvantage was detected for isolates of either of the two clones in the in vitro experiments and this regained fitness remained for isolates collected up to 18 months. Competition analysis of an in vitro isolated erm(G) positive transconjugant also demonstrated an initial reduction of fitness that was restored over time. The results indicate that the biological cost associated with a resistance gene can rapidly be compensated during in vivo growth. Thus, once the resistant clone has gained its resistance determinant it will be difficult to eliminate.
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| 25. |
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| 26. |
- Murphy, Elizabeth, et al.
(författare)
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Identification of pili on the surface of Finegoldia magna - A Gram-positive anaerobic cocci.
- 2014
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Ingår i: Anaerobe. - : Elsevier BV. - 1095-8274 .- 1075-9964. ; 27:Mar 29, s. 40-49
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Tidskriftsartikel (refereegranskat)abstract
- Pili have only been discovered in the major Gram-positive pathogens in the past decade and they have been found to play an important role in colonisation and virulence. Pili have been shown to have many important functions including attachment to host tissues, mediating bacterial aggregation, biofilm formation and binding to proteins in the extracellular matrix. In this study, sortase-dependent pili have been found to be expressed on the surface of Finegoldia magna ALB8. F. magna is a Gram-positive anaerobic coccus that, primarily, is a commensal of the skin and mucous membranes, but has also been isolated from various clinical infection sites and is associated with soft-tissue abscesses, wound infections and bone and prosthetic joint infections. In this study, F. magna ALB8 was found to harbour three sortases at the pilus locus, two of which bear high similarity to class C sortases in Streptococcus pneumoniae. Two putative sortase-dependent pili proteins were found in the locus, with one being identified as the major pilus subunit, Fmp1 (F. magna pilus subunit 1), due to its high similarity to other major pilus proteins in prominent Gram-positive pathogens. The presence of sortase-dependent pili was confirmed experimentally through recombinant production of Fmp1 and production of antiserum. The Fmp1 antiserum was used in Western blot to show the presence of a high molecular weight protein ladder, characteristic of the presence of pili, in trypsin released cell wall surface proteins from F. magna. The presence of sortase-dependent pili was visually confirmed by transmission electron microscopy, which showed the binding of gold labelled anti-Fmp1 to individual pilus proteins along the pilus. Furthermore, pili could also be found to bind and interact with keratinocytes in the epidermal layer of human skin, suggesting an adhesive role for pili on F. magna. Our work represents the first description of pilus structures in F. magna. This discovery further elucidates F. magna physiology and allows for additional analysis of host-bacterial interactions in future studies.
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| 27. |
- Neilands, Jessica, et al.
(författare)
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Bacterial profiles and proteolytic activity in peri-implantitis versus healthy sitesBacterial profiles and proteolytic activity in peri-implantitis versus healthy sites
- 2015
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Ingår i: Anaerobe. - : Academic Press. - 1075-9964 .- 1095-8274. ; 35, s. 28-34
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Tidskriftsartikel (refereegranskat)abstract
- Peri-implantitis is a biofilm-induced destructive inflammatory process that, over time, results in loss of supporting bone around an osseointegrated dental implant. Biofilms at peri-implantitis sites have been reported to be dominated by Gram-negative anaerobic rods with a proteolytic metabolism such as, Fusobacterium, Porphyromonas, Prevotella and Tannerella, as well as anaerobic Gram-positive cocci. In this study, we hypothesized that protease activity is instrumental in driving bone destruction and we therefore compared the microbial composition and level of protease activity in samples of peri-implant biofluid (PIBF) from 25 healthy subjects (H group) and 25 subjects with peri-implantitis (PI group). Microbial composition was investigated using culture techniques and protease activity was determined using a FITC-labelled casein substrate. The microbial composition was highly variable in subjects both in the H and PI groups but one prominent difference was the prevalence of Porphyromonas/Prevotella and anaerobic Gram positive cocci which was significantly higher in the PI than in the H group. A subgroup of subjects with peri-implantitis displayed a high level of protease activity in the PIBF compared to healthy subjects. However, this activity could not be related to the presence of specific bacterial species. We propose that a high level of protease activity may be a predictive factor for disease progression in peri-implantitis. Further longitudinal studies are however required to determine whether assessment of protease activity could serve as a useful method to identify patients at risk for progressive tissue destruction.
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| 28. |
- Neilands, Jessica, et al.
(författare)
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Parvimonas micra stimulates expression of gingipains from Porphyromonas gingivalis in multi-species communities
- 2019
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Ingår i: Anaerobe. - : Elsevier. - 1075-9964 .- 1095-8274. ; 55, s. 54-60
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Tidskriftsartikel (refereegranskat)abstract
- Dental biofilms are complex ecosystems containing many bacterial species that live in mutualistic relationships. These interactions can profoundly affect the virulence properties of the community. In this study we investigated how the production of gingipains, virulence factors from Porphyromonas gingivalis important in periodontal disease, was affected by other commonly found members of the sub-gingival microbiome. To mimic the subgingival microbiome, multispecies consortia (P. gingivalis, Fusobacterium nucleatum, Actinomyces naeslundii, Streptococus oralis, Streptococcus mitis, Streptococcus gordonii and Streptococcus cristatus, with or without Parvimonas micra) as well as dual species consortia (P. gingivalis with P. micra, S. oralis or F. nucleatum) were constructed and maintained anaerobically in 10% serum for up to seven days. The number of P. gingivalis was determined by plating on Brucella agar and the gingipain specific fluorogenic substrate BikKam-10 was used to investigate gingipain activity. The effect of secreted products from P. micra on gingipain activity was investigated by adding supernatants from P. micra to P. gingivalis cultures. The most prominent secreted proteins in the supernatant were identified using mass spectrometry. P. gingivalis was unable to grow in serum, either alone or in the presence of S. oralis or F. nucleatum. In contrast, with P. micra growth was significantly enhanced and this was associated with an increase in gingipain activity. In the multi-species consortia, the presence of P. micra caused a 13-fold increase in gingipain activity. Exposure of P. gingivalis to supernatants from P. micra for 24 hours caused a 3-fold increase in gingipain activity. This effect was reduced by 43% after heat-treatment of the supernatant. Two dimensional gel electrophoresis revealed that several of the most prominent proteins in the P. micra supernatant were glycolytic enzymes. The results from this study suggests that gingipains are produced in response to a P. micra derived signaling molecule that is most likely a protein. This is the first time it has been shown that P. micra can affect P. gingivalis virulence properties. This is likely to be of significance for the development of be of periodontitis since these two microorganisms are often found together in the subgingival biofilm.
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| 29. |
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| 30. |
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| 31. |
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| 32. |
- Oh, Herin, et al.
(författare)
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Efflux-mediated fluoroquinolone resistance in the Bacteroides fragilis group
- 2002
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Ingår i: Anaerobe. - : Elsevier BV. - 1075-9964 .- 1095-8274. ; 8:5, s. 277-282
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Tidskriftsartikel (refereegranskat)abstract
- In order to investigate the role of efflux pumps in fluoroquinolone resistance, 35 Bacteroides fragilis group isolates with various resistance patterns against ciprofloxacin, levofloxacin, moxifloxacin and clinafloxacin were studied. The gyrA genotypes were known in all isolates studied. The accumulation of ciprofloxacin with and without carbonyl cyanide m-chlorophenylhydrazone (CCCP) was investigated using a silicon oil based fluorometric assay. Seventeen of 25 multiquinolone-resistant strains had significantly increased ciprofloxacin accumulation in the presence of CCCP compared to the corresponding susceptible type strains. Ten of the resistant isolates with increased efflux had no target mutations at positions 82 or 86 of their GyrA subunits. Strains with highly enhanced efflux were consequently shown to have a significant decrease of quinolone MIC values in the presence of efflux pump inhibitor. The results of the present study propose that high levels of resistance to older as well as newer fluoroquinolones, could be explained by increased activity of efflux pumps in B. fragilis group strains.
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| 33. |
- Pahumunto, Nuntiya, et al.
(författare)
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Virulence of Aggregatibacter actinomycetemcomitans serotypes and DGGE subtypes isolated from chronic adult periodontitis in Thailand.
- 2015
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Ingår i: Anaerobe. - : Elsevier BV. - 1095-8274 .- 1075-9964. ; 36, s. 60-4
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Tidskriftsartikel (refereegranskat)abstract
- A high proportion of non-serotypeable isolates of Aggregatibacter actinomycetemcomitans among Thai periodontitis cases has been previously reported. The aim of this study was to investigate the expression of leukotoxin and toxicity, cytolethal distending toxin (Cdts), and internalization and the killing effect on fibroblasts by A.actinomycetemcomitans subtypes from Thai chronic periodontitis cases. A total of 96 A.actinomycetemcomitans strains from 37 periodontitis cases, previously serotyped with PCR and subtyped with DGGE, were examined for the presence of the ltx gene and cdt genes (cdtBC), and tested for leukotoxin expression, leukotoxicity, internalization, and apoptosis of fibroblast cells. The ltx gene was present in all isolates, while 84.4% showed the cdtBC gene. Two strains with a JP2-like ltx gene with a deletion of 530bp in the promoter region, serotyped as c, showed virulence of similar magnitude to the JP2 strain. Furthermore, a higher virulence was found in the two non-serotypeable DGGE subtypes, NS1 and NS2, compared with the serotypeable strains (serotype a-f, serotype b and d were absent). Generally, the virulence of strains obtained from deep periodontal pockets was higher than those isolated from shallow non-bleeding pockets. A.actinomycetemcomitans subtypes isolated from adult Thais with chronic periodontitis showed a highly variable virulence, leukotoxin expression, leukotoxicity, internalization and apoptosis of fibroblast, and are regulated both genetically and environmentally.
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| 34. |
- Raner, Elisabeth, et al.
(författare)
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pH and bacterial profile of dental plaque in children and adults of a low caries population
- 2014
-
Ingår i: Anaerobe. - : Elsevier BV. - 1075-9964 .- 1095-8274. ; 27, s. 64-70
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Tidskriftsartikel (refereegranskat)abstract
- Objective: This study compares pH and microbiological profile of dental plaque in children and adults of a low caries population. Material and methods: Thirty-nine children, 12-14 years of age and 45 adults between 20 and 39 years of age in 5 Karen villages of the Tak province, Northern Thailand were examined for plaque, calculus, caries (DMFT) and pH measurements in resting plaque and after a sucrose rinse. Information on dietary and oral hygiene habits was obtained through interviews using a fixed questionnaire. Microbiological profile of plaque samples was analyzed with DNA-DNA checkerboard technique. Results: Mean DMFT was 0.77 +/- 1.56 and 87% of the adults and 67% of the children were caries free (p < 0.05). The mean resting pH was for both age groups in the range of 7.0-7.1 and significantly higher than a Swedish caries free reference group. Karen adult men had significantly lower pH minimum than females and children (p < 0.05). Supragingival plaque samples showed high levels of low acidogenic and anaerobic species, which dominated over strong acid producers such as streptococci. Conclusion: The study indicates that the Karen children and adults has a plaque physiology and microbiology predominating by low acidogenic anaerobes, which in addition to the low sucrose intake explains the low caries prevalence in this population. (C) 2014 Elsevier Ltd. All rights reserved.
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| 35. |
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| 36. |
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| 37. |
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| 38. |
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| 39. |
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| 40. |
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| 41. |
- Skarin, Hanna, et al.
(författare)
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The same clade of Clostridium botulinum strains is causing avian botulism in southern and northern Europe
- 2014
-
Ingår i: Anaerobe. - : Elsevier BV. - 1075-9964 .- 1095-8274. ; 26, s. 20-23
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Tidskriftsartikel (refereegranskat)abstract
- Avian botulism is a paralytic disease caused by Clostridium botulinum-produced botulinum neurotoxins (BoNTs), most commonly of type C/D. It is a serious disease of waterbirds and poultry flocks in many countries in Europe. The objective of this study was to compare the genetic relatedness of avian C botulinum strains isolated in Spain with strains isolated in Sweden using pulsed-field gel electrophoresis (PFGE). Fifteen strains were isolated from Spanish waterbirds using an immunomagnetic separation technique. Isolates were characterized by PCR, and all were identified as the genospecies Clostridium novyi sensu lato and eight harboured the gene coding for the BoNT type C/D. PFGE analysis of the strains revealed four highly similar pulsotypes, out of which two contained strains from both countries. It also showed that outbreaks in wild and domestic birds can be caused by the same strains. These results support a clonal spreading of the mosaic C botulinum type C/D through Europe and give relevant information for future epidemiological studies. (C) 2014 Elsevier Ltd. All rights reserved.
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| 42. |
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| 43. |
- Unemo, Magnus, 1970-, et al.
(författare)
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Genetic homogeneity/heterogeneity of Propionibacterium acnes isolated from patients during cardiothoracic reoperation
- 2007
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Ingår i: Anaerobe. - London : Academic Press. - 1075-9964 .- 1095-8274. ; 13:3-4, s. 121-126
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Tidskriftsartikel (refereegranskat)abstract
- Following cardiothoracic surgery, deep sternal wound infection (SWI) remains one of the most severe complications. Recently, Propionibacterium acnes has been suspected as an etiological agent of deep SWI. However, this bacterium constitutes part of the resident micro-flora of the human skin. Consequently, findings of P. acnes in invasive samples are difficult to value. The aims of this study were to develop and optimize a pulsed-field gel electrophoresis (PFGE) protocol for P. acnes, in order to investigate the genetic homogeneity/heterogeneity of P. acnes isolates from multiple tissue samples (predominantly biopsies), collected at different locations, from 12 patients during cardiothoracic reoperation. There were 24 distinguishable PFGE fingerprints identified among the P. acnes isolates (n=54). Five (42%) of the patients carried only isolates that were interpreted as presumably clonally related. From the remaining seven patients, two or three different P. acnes clones were cultured, however, from six of them, the clones were identified in multiple samples. P. acnes may be a relatively frequent etiological agent of postoperative cardiothoracic infections. Existence of several clonally related P. acnes isolates derived from multiple samples from patients suffering from deep SWI after cardiothoracic surgery has not previously been shown.
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| 44. |
- Vargas, J. E., et al.
(författare)
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Effects of supplemental plant oils on rumen bacterial community profile and digesta fatty acid composition in a continuous culture system (RUSITEC)
- 2020
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Ingår i: Anaerobe. - : Elsevier BV. - 1075-9964 .- 1095-8274. ; 61
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Tidskriftsartikel (refereegranskat)abstract
- Lipid supplementation of ruminant diets may trigger changes in the ruminal microbiota and in anaerobic digestion. Changes in the bacterial community composition and in the fatty acid hydrogenation caused by the addition of different supplemental plant oils to a high concentrate diet were investigated in vitro using RUSITEC (rumen simulation technique) fermenters. The control (CTR) diet was a high-concentrate total mixed ration for dairy sheep, with no supplementary oil. The other experimental diets were supplemented with olive (OLV), sunflower (SFL) or linseed (LNS) oils at 6% (dry matter basis). Four RUSITEC fermenters were used for each experimental diet, all inoculated with rumen digesta of sheep. Extent of dry matter and fat degradation, composition of the bacterial community and long-chain fatty acids in digesta were determined. The addition of plant oils increased (P < 0.001) apparent degradation of fat in the fermenters, whereas fermentation kinetics (gas production and average fermentation rate) were lower (P < 0.05) with the LNS than with the CTR diet. Hydrogenation of C18 unsaturated fatty acids (P < 0.05), in particular that of oleic acid (P < 0.001), and stearic acid proportion (P < 0.001) were reduced, and oleic acid proportion was increased (P < 0.001) with all oil supplements. Addition of OLV decreased linoleic and LNS increased α-linolenic (P < 0.001), whereas conjugated linoleic was increased with SFL oil (P = 0.025) and vaccenic increased with both SFL and LNS oils (P = 0.008). Addition of 6% OLV and LNS reduced (P < 0.05) microbial community diversity and quantity of total bacteria relative to the control. Some specific microbial groups were affected (P < 0.001) by oil addition, with less relative abundance of Clostridiales and Actinobacteria and increased Bacteroidales, Aeromonadales and Lactobacillales species. In conclusion, the supplementation of high-concentrate ruminant diets with plant oils, in particular from sunflower or linseed, causes shifts in the rumen microbiota and fatty acid hydrogenation in the rumen increasing the formation of vaccenic and conjugated linoleic acids.
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| 45. |
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| 46. |
- Woudstra, C., et al.
(författare)
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Validation of a real-time PCR based method for detection of clostridium botulinum types C, D and their mosaic variants C-D and D-C in a multicenter collaborative trial
- 2013
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Ingår i: Anaerobe. - : Elsevier BV. - 1075-9964 .- 1095-8274. ; 22, s. 31-37
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Tidskriftsartikel (refereegranskat)abstract
- Two real-time PCR arrays based on the GeneDisc® cycler platform (Pall-GeneDisc Technologies) were evaluated in a multicenter collaborative trial for their capacity to specifically detect and discriminate Clostridium botulinum types C, D and their mosaic variants C-D and D-C that are associated with avian and mammalian botulism. The GeneDisc® arrays developed as part of the DG Home funded European project 'AnibioThreat' were highly sensitive and specific when tested on pure isolates and naturally contaminated samples (mostly clinical specimen from avian origin). Results of the multicenter collaborative trial involving eight laboratories in five European Countries (two laboratories in France, Italy and The Netherlands, one laboratory in Denmark and Sweden), using DNA extracts issued from 33 pure isolates and 48 naturally contaminated samples associated with animal botulism cases, demonstrated the robustness of these tests. Results showed a concordance among the eight laboratories of 99.4%-100% for both arrays. The reproducibility of the tests was high with a relative standard deviation ranging from 1.1% to 7.1%. Considering the high level of agreement achieved between the laboratories these PCR arrays constitute robust and suitable tools for rapid detection of C.botulinum types C, D and mosaic types C-D and D-C. These are the first tests for C.botulinum C and D that have been evaluated in a European multicenter collaborative trial. © 2013 Elsevier Ltd.
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| 48. |
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