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- Basic, Amina, et al.
(författare)
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Antibiotic resistance among Aerobic Gram-Negative Bacilli isolated from patients with oral inflammatory dysbiotic conditions-a retrospective study
- 2024
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Ingår i: FRONTIERS IN DENTAL MEDICINE. - 2673-4915. ; 5
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Aerobic Gram-Negative Bacilli (AGNB) are not part of the resident oral microflora but are occasionally found in high abundance under inflammatory dysbiotic conditions at various oral niches. The aim of the present study was to investigate the identity and antibiotic susceptibility of AGNB isolated from patients in Sweden with mucosal lesions, periodontitis, and peri-implantitis, with special attention to antibiotic resistance and on the presence of phenotypic Extended Spectrum Beta-Lactamase (ESBL) isolates. Materials and methods: Microbiolgical samples were harvested from 211 patients in total, experiencing mucosal lesions (N = 113), periodontitis (N = 62), or peri-implantitis (N = 36). The growth of AGNB's was semiquantified by selective and non-selective culture and the strains were isolated, identified, and tested for antibiotic susceptibility. A total of 251 AGNB strains, occurring in moderate to heavy growth (>100 CFU/ml sample), indicating a dysbiotic microbiota, were identified. The disc diffusion method was used for screening of the antibiotic susceptibility of the isolates. Phenotypic identification of ESBL isolates was based on resistance to ceftazidime and/or cefotaxime. Results: The most commonly detected AGNB isolates in oral inflammatory dysbiotic conditions were fermentative species belonging to Enterobacteriaceae e.g. Citrobacter spp., Enterobacter spp., Escherichia coli, Klebsiella spp, and the non-fermentative environmental Burkholderia cepacia, Pseudomonas spp., and Stenotrophomonas maltophilia. No clear trends were seen in frequency of the various species in samples from mucosal lesions, severe periodontitis, and peri-implantitis cases. The 138 Enterobacteriaceae isolates and 113 environmental AGNB isolated showed a high antibiotic resistance in general against antibiotics commonly used in dentistry (Amoxicillin, Amoxicillin + Clavulanic acid, Ampicillin, Clindamycin, Doxycycline, Erythromycin, Oxacillin, PenicillinV, and Tetracycline). The majority of these isolates were susceptible to ciprofloxacin. Ten isolates (4.1%) were phenotypically classified as ESBL positive. The ESBL isolates were predominantly found among isolates of S. maltophilia, while only one ESBL positive isolate was found among Enterobacteriaceae. Conclusions: Phenotypically identified ESBL isolates can occasionally be present among oral AGNB strains isolated in abundance from the dysbiotic microbiota occurring in cases with oral mucosal lesions, severe periodontitis, or peri-implantitis.
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| 2. |
- Basic, Amina, et al.
(författare)
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Estimation of bacterial hydrogen sulfide production in vitro.
- 2015
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Ingår i: Journal of oral microbiology. - : Informa UK Limited. - 2000-2297. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- Oral bacterial hydrogen sulfide (H2S) production was estimated comparing two different colorimetric methods in microtiter plate format. High H2S production was seen for Fusobacterium spp., Treponema denticola, and Prevotella tannerae, associated with periodontal disease. The production differed between the methods indicating that H2S production may follow different pathways.
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| 3. |
- Blomqvist, Susanne, 1953, et al.
(författare)
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Phenotype, genotype, and antibiotic susceptibility of Swedish and Thai oral isolates of Staphylococcus aureus
- 2015
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Ingår i: Journal of Oral Microbiology. - : Informa UK Limited. - 2000-2297. ; 7:1, s. 1-7
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Tidskriftsartikel (refereegranskat)abstract
- Objective: The present study investigated phenotypes, virulence genotypes, and antibiotic susceptibility of oral Staphylococcus aureus strains in order to get more information on whether oral infections with this bacterium are associated with certain subtypes or related to an over-growth of the S. aureus variants normally found in the oral cavity of healthy carriers. Materials and methods: A total number of 157 S. aureus strains were investigated. Sixty-two strains were isolated from Swedish adults with oral infections, 25 strains were from saliva of healthy Swedish dental students, and 45 strains were from tongue scrapings of HIV-positive subjects in Thailand, and 25 Thai strains from non-HIV controls. The isolates were tested for coagulase, nitrate, arginine, and hemolysin, and for the presence of the virulence genes: hlg, clfA, can, sdrC, sdrD, sdrE, map/eap (adhesins) and sea, seb, sec, tst, eta, etb, pvl (toxins). MIC90 and MIC50 were determined by E-test against penicillin V, oxacillin, amoxicillin, clindamycin, vancomycin, fusidic acid, and cefoxitin. Results: While the hemolytic phenotype was significantly (p<0.001) more common among the Thai strains compared to Swedish strains, the virulence genes were found in a similar frequency in the S. aureus strains isolated from all four subject groups. The Panton-Valentine leukocidin (PVL) genotype was found in 73-100% of the strains. More than 10% of the strains from Swedish oral infections and from Thai HIVpositives showed low antibiotic susceptibility, most commonly for clindamycin. Only three methicillinresistant S. aureus (MRSA) strains were identified, two from oral infections and one from a Thai HIV patient. Conclusions: S. aureus is occasionally occurring in the oral cavity in both health and disease in Sweden and Thailand. It is therefore most likely that S. aureus in opportunistic oral infections originate from the oral microbiota. S. aureus should be considered in case of oral infections and complaints and the antibiotic susceptibility (including MRSA) should regularly be checked. The frequent presence of S. aureus, although in low numbers among students and staff, emphasizes the importance of standard infection control precautions and of using diagnostic test in the dental clinic. © 2015 Susanne Blomqvist et al.
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| 4. |
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| 5. |
- Lexner, Michala Oron, et al.
(författare)
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Microbiological profiles in saliva and supragingival plaque from caries-active adolescents before and after a short-term daily intake of milk supplemented with probiotic bacteria - a pilot study.
- 2010
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Ingår i: Oral health & preventive dentistry. - 1602-1622. ; 8:4, s. 383-3888
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: The aim of the present pilot study was to investigate the microbial profile in saliva and supragingival plaque samples collected from caries-active adolescents before and after a daily short-term intake of milk supplemented with the probiotic bacteria. MATERIALS AND METHODS: The present study group consisted of 18 caries-active adolescents of both sexes who volunteered for participation giving an informed consent. The study has a randomised placebo-controlled double-blind pilot design with two parallel arms. After a 2-week run-in period, the subjects were instructed to drink 2.5 dl of milk supplemented with Lactobacillus rhamnosus LB21 (107 CFU/ml) (test) or standard control milk (placebo) once daily for a period of 2 weeks (intervention period). Samples of stimulated whole saliva and supragingival plaque were collected at baseline (after run-in) and immediately after the end of the intervention period (follow-up). The salivary levels of mutans streptococci and lactobacilli were estimated by conventional culturing on selective agar plates. The presence and level of 19 oral species associated with the caries process were determined using the checkerboard DNA-DNA hybridisation technique. Differences between the groups were assessed using the non-parametric Wilcoxon–Mann–Whitney and chi-square tests. RESULTS: The mean caries experience was high with an average of 7.0 ± 3.8 proximal enamel lesions. The most prevalent dominating species in the plaque samples were Streptococcus mitis, Veillonella parvula and Streptococcus gordonii. The saliva samples displayed a more mixed profile, with Streptococcus mitis, Rothia dentocariosa, Lactobacillus casei and Lactobacillus curvata being frequently identified species. All of the subjects harboured mutans streptococci in their saliva, with 61% of them colonised with salivary lactobacilli. No statistically significant differences in the microbial profiles or the estimated counts between the baseline and follow-up samples, or between the two study groups, were observed. CONCLUSIONS: The present study showed that a short-term daily intake of milk supplemented with the probiotic bacterium L. rhamnosus LB21 did not significantly affect the microbial profiles or the levels of caries-associated bacteria in saliva and supragingival plaque samples collected from caries-active adolescents.
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| 6. |
- Nelun Barfod, Mette, et al.
(författare)
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Oral microflora in infants delivered vaginally and by caesarean section.
- 2011
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Ingår i: International journal of paediatric dentistry / the British Paedodontic Society [and] the International Association of Dentistry for Children. - 1365-263X. ; 21:6, s. 401-6
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND. Early in life, vaginally delivered infants exhibit a different composition of the gut flora compared with infants delivered by caesarean section (C-section); however, it is unclear whether this also applies to the oral cavity. AIM. To investigate and compare the oral microbial profile between infants delivered vaginally and by C-section. DESIGN. This is a cross-sectional case-control study. Eighty-four infants delivered either vaginally (n = 42) or by C-section (n = 42) were randomly selected from the 2009 birth cohort at the County Hospital in Halmstad, Sweden. Medically compromised and premature children (<32 weeks) were excluded. The mean age was 8.25 months (range 6-10 months), and parents were asked to complete a questionnaire on socioeconomic factors, lifestyle, and hygiene habits. Saliva was collected and analysed using checkerboard DNA-DNA hybridization. RESULTS. A higher prevalence of salivary Streptococcus salivarius, Lactobacillus curvata, Lactobacillus salivarius, and Lactobacuillus casei was detected in infants delivered vaginally (P < 0.05). The caries-associated bacteria Streptococcus mutans and Streptococcus sobrinus were detected in 63% and 59% of all children, respectively. CONCLUSION. A significantly higher prevalence of certain strains of health-related streptococci and lactobacilli was found in vaginally delivered infants compared with infants delivered by C-section. The possible long-term effects on oral health need to be further investigated.
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