No evidence of triclosan-resistant bacteria following long-term use of triclosan-containing toothpaste.

BACKGROUND AND OBJECTIVE: There is a paucity of data in relation to the possible emergence of triclosan (TCS)-resistant bacteria following long-term exposure to TCS toothpaste. Therefore, this study investigated whether long-term continuous exposure to TCS in toothpaste selects for TCS-resistant bacteria within the oral biofilm. MATERIAL AND METHODS: Dental plaque samples were collected from 40 individuals during year 5 of a randomised controlled trial. Participants had been randomly assigned to use TCS (3000 µg/mL TCS) (n = 18) or placebo toothpaste (n = 22). Diluted plaque samples were plated on to Wilkins-Chalgren agar plates containing 5% (v/v) laked sheep red blood cells and TCS (concentrations ranging from 25 to 150 µg/mL) and incubated at 37 °C under microaerophilic and anaerobic conditions for 2-10 d. Selected bacterial isolates were identified by partial 16S rDNA sequencing and TCS minimum inhibitory concentration (MIC) determined for each isolate. RESULTS: At 3000 µg/mL TCS no growth was observed under microaerophilic or anaerobic conditions in either group. The MICs of TCS for all isolates ranged from 125 to 1000 µg/mL in both groups. Species common to both groups had similar MICs. Veillonella parvula and Campylobacter gracilis were the most frequent isolates from both groups, with similar MICs in both groups. CONCLUSION: The use of TCS-containing toothpaste did not appear to lead to an increase in MIC of TCS of oral bacterial isolates.

Improved periodontal health and cardiovascular risk.

BACKGROUND: Previous studies have demonstrated variable effects on systemic inflammatory and immune responses following improved periodontal health. This study examined changes in serum levels of the inflammatory mediators IL-1ß, IL-6, TNF-α and sICAM-1, and antibodies to Porphyromonas gingivalis, human heat shock protein (hHSP) 60 and P. gingivalis GroEL following improvement in periodontal health in high cardiovascular (CV) risk and low CV-risk patients. METHODS: Patients retrospectively selected from a longitudinal study, had undergone yearly periodontal examinations and peripheral blood collections. They had demonstrated a quantifiable improvement in periodontal health (>60% reduction in number of sites with probing depth ≥ 4 mm from the baseline visit) and could be classified as either high CV-risk (≥ 6 classical risk factors, n = 13) or low CV-risk (≤ 1 classical risk factor, n = 14). Serum levels of the cytokines and antibodies were measured using ELISA. RESULTS: For sICAM-1 and anti-P. gingivalis GroEL and anti-hHSP60 antibodies, most patients recorded decreased levels. Reductions in serum sICAM-1 levels were more notable in low CV-risk patients (p = 0.006); and reductions in levels of anti-P. gingivalis GroEL and anti-hHSP60 antibodies (p = 0.001 and 0.009 respectively) were more notable in high CV-risk patients. CONCLUSIONS: This study found that subsequent to improved periodontal health, the anti-HSP (HSP60 and GroEL) antibody response was reduced, particularly for high CV-risk patients. sICAM-1 levels were also lowered, more so for low CV-risk patients.

Validation of the hospital anxiety and depression scale and the psychological disorder among premature ejaculation subjects.

Premature ejaculation (PE) is a common sexual dysfunction among the general population. PE has often been associated with a psychological state of mind. Hospital Anxiety and Depression Scale (HADS) can be used as an instrument to assess the emotional and psychological state. The present study was designed to assess the reliability and validity of the HADS in a Malaysian population. The validity and reliability were studied in subjects with and without PE. Test-retest methodology was used to assess the reliability whereas Cronbach's alpha was used to assess the internal consistency. In the control and the PE groups, the internal consistency was good and a high degree of internal consistency was observed for all 14 items. In the control group, the Cronbach's alpha values at baseline were from 0.811 to 0.834, whereas for retest, the Cronbach's alpha values were from 0.821-0.838 items. Intraclass correlation coefficient (ICC) was high for the control (0.797-0.868: baseline and 0.805-0.872: retest) and PE group (0.822-0.906: baseline and 0.785-0.887: retest). The high value of ICC and the internal consistency was due to high reliability and consistency of the items at 2-week interval. A degree of significance between the baseline and week-2 scores was observed across all items in the PE group but not in the control group. The HADS is a suitable, reliable, valid and sensitive instrument to measure the clinical change for anxiety and depression in the Malaysian population.

Comparison of Campylobacter jejuni PFGE and Penner subtypes in human infections and in water samples from the Taieri River catchment of New Zealand.

AIMS: To determine the degree of overlap in strain types of Campylobacter jejuni isolated from clinical cases and water samples from the Taieri catchment in the South Island of New Zealand. METHODS AND RESULTS: Thermophilic Campylobacter were collected from human cases of infection, the main stem of the Taieri River and streams within distinct land-use types over a 1-year period. Campylobacter jejuni (187 isolates) and Campylobacter lari (four isolates) were identified using a multiplex polymerase chain reaction protocol. Isolates were typed by the Penner method and pulsed-field gel electrophoresis (PFGE) utilizing two restriction endonucleases. Several serotypes and PFGE types occurred in both water samples and clinical cases when the restriction profiles for each enzyme were considered separately. However, when PFGE profiles and serotyping were combined, there was no overlap between Camp. jejuni types from water and clinical cases. CONCLUSIONS: The results of this study indicate that recreational water in the Taieri catchment is not a major source of campylobacteriosis in the Dunedin area. SIGNIFICANCE AND IMPACT OF THE STUDY: This study suggests the risk of acquiring campylobacteriosis from surface waters in the Taieri catchment is considerably lower than previously predicted and highlights the necessity of using two endonucleases in PFGE typing.

Genotypic comparison of bacteria recovered from human bite marks and teeth using arbitrarily primed PCR.

AIMS: This study assessed, for forensic purposes, the feasibility of genotypically matching oral streptococci recovered from recent human bite marks with those from the teeth of the biter. METHODS AND RESULTS: Streptococci were isolated from the incisors of eight volunteers. Arbitrarily primed PCR (AP-PCR) distinguished 106 streptococcal genotypes among the participants, each harbouring at least eight distinct strains. In a crime simulation, a sample from an experimental bite mark was analysed by an experimenter unaware of its origin. The bacteria were unambiguously matched to the biter by comparing the amplicon profiles with those from the eight participants. In contrast, bacteria from an additional bite mark (not generated by one of the original participants) could not be matched to any of the eight participants. Between 20 and 78% of catalogued bacterial genotypes were recovered 12 months later from each participant. Throughout the study period, none of the bacterial genotypes were shared between participants. CONCLUSIONS: Streptococci isolated from recent bite marks can be catalogued by AP-PCR and matched to the teeth responsible for the bite. SIGNIFICANCE AND IMPACT OF THE STUDY: The study provides 'proof of concept' that genotypic analysis of streptococci from bite marks may provide valuable forensic evidence in situations where the perpetrator's DNA cannot be recovered.

Influence of different functional elements of plasmid pGT232 on maintenance of recombinant plasmids in Lactobacillus reuteri populations in vitro and in vivo.

Plasmid pGT232 (5.1 kb), an indigenous plasmid of Lactobacillus reuteri 100-23, was determined, on the basis of nucleotide and deduced protein sequence data, to belong to the pC194-pUB110 family of plasmids that replicate via the rolling-circle mechanism. The minimal replicon of pGT232 was located on a 1.7-kb sequence consisting of a double-strand origin of replication and a gene encoding the replication initiation protein, repA. An erythromycin-selectable recombinant plasmid containing this minimal replicon was stably maintained (>97% erythromycin-resistant cells) without antibiotic selection in an L. reuteri population under laboratory growth conditions but was poorly maintained (<33% resistant cells) in the L. reuteri population inhabiting the murine gastrointestinal tract. Stable maintenance (>90% resistant cells) of pGT232-derived plasmids in the lactobacillus population in vivo required an additional 1.0-kb sequence which contained a putative single-strand replication origin (SSO). The SSO of pGT232 is believed to be novel and functions in an orientation-specific manner.

Cloning and expression of an endo-1,3-1,4-beta-glucanase gene from Bacillus macerans in Lactobacillus reuteri.

Strains of the gastrointestinal species Lactobacillus reuteri were electrotransformed with plasmid constructs containing the endo-1,3-1,4-beta-glucanase gene (bglM) of Bacillus macerans. The enzyme was expressed and secreted by the lactobacilli. A plasmid construct containing the bglM gene lacking its promoter was derived and was demonstrated to be useful as a promoter probe vector.