Changes in oral microflora following 0.3% cetylpyridinium chloride-containing mouth spray intervention in adult volunteers after professional oral care: Randomized clinical study.

OBJECTIVES: This study explored the changes in bacterial flora composition and total bacterial count in the saliva and tongue coating, along with the change in the tongue coating index (TCI) following an intervention with 0.3% cetylpyridinium chloride (CPC) mouth spray after professional oral care. MATERIALS AND METHODS: Fifty-two adult volunteers aged 30-60 years were equally divided into CPC spray (n = 26) and control (n = 26) groups. All subjects underwent scaling and polishing. The CPC spray group was administered four puffs of CPC spray to the tongue dorsum four times a day for 3 weeks. The control group performed only routine daily oral care (brushing) and did not use any other spray. Bacteriological evaluation of saliva and tongue coating was performed using 16S ribosomal RNA gene sequencing and quantitative polymerase chain reaction. The tongue coating was evaluated to calculate the TCI. A per-protocol analysis was conducted for 44 subjects (CPC spray group, n = 23; control group, n = 21). RESULTS: At 1 and 3 weeks after CPC spray use, the flora of the saliva and tongue coating changed; the genus Haemophilus was dominant in the CPC spray group, whereas the genus Saccharibacteria was dominant in the control group. The sampling time differed among individual participants, which may have affected the bacterial counts. There was no significant intragroup change in TCI in either group. CONCLUSIONS: CPC spray affected the bacterial flora in the saliva and tongue coating, particularly with respect to an increase in the abundance of Haemophilus. However, CPC spray did not change the TCI. These results suggest that it may be optimal to combine CPC spray with a physical cleaning method such as using a tongue brush or scraper. Clinical Trial Registration: University Hospital Medical Information Network UMIN000041140.

Genetic Homology between Bacteria Isolated from Pulmonary Abscesses or Pyothorax and Bacteria from the Oral Cavity.

Pulmonary abscesses and pyothorax are bacterial infections believed to be caused primarily by oral microbes. However, past reports addressing such infections have not provided genetic evidence and lack accuracy, as they used samples that had passed through the oral cavity. The aim of this study was to determine whether genetically identical bacterial strains exist in both the oral microbiota and pus specimens that were obtained percutaneously from pulmonary abscesses and pyothorax, without oral contamination. First, bacteria isolated from pus were identified by 16S rRNA gene sequencing. It was then determined by quantitative PCR using bacterial-species-specific primers that DNA extracted from paired patient oral swab sample suspensions contained the same species. This demonstrated sufficient levels of bacterial DNA of the targeted species to use for further analysis in 8 of 31 strains. Therefore, the whole-genome sequences of these eight strains were subsequently determined and compared against an open database of the same species. Five strain-specific primers were synthesized for each of the eight strains. DNA extracted from the paired oral swab sample suspensions of the corresponding patients was PCR amplified using five strain-specific primers. The results provided strong evidence that certain pus-derived bacterial strains were of oral origin. Furthermore, this two-step identification process provides a novel method that will contribute to the study of certain pathogens of the microbiota. IMPORTANCE We present direct genetic evidence that some of the bacteria in pulmonary abscesses and pyothorax are derived from the oral flora. This is the first report describing the presence of genetically homologous strains both in pus from pulmonary abscesses and pyothorax and in swab samples from the mouth. We developed a new method incorporating quantitative PCR and next-generation sequencing and successfully prevented contamination of pus specimens with oral bacteria by percutaneous sample collection. The new genetic method would be useful for enabling investigations on other miscellaneous flora; for example, detection of pathogens from the intestinal flora at the strain level.

Effects of Diluents, Saliva and Other Organics on the Microbicidal Activity of Cetylpyridinium Chloride and Povidone-iodine.

Povidone-iodine (PVP-I) is used for infection control and preoperative sterilization of the oral and pharyngeal regions. Marketed preparations containing cetylpyridinium chloride (CPC) are used to inhibit growth of oral bacteria. We conducted an in vitro study of the sterilizing effects of these microbicides on 10 oral bacterial strains and fungi related to pneumonia and periodontal disease, after dilution with phosphate-buffered saline (PBS), saliva, and components in saliva. The CPC solution was evaluated at 50 mg/100 mL, which is the concentration used in products. CPC sterilized all strains within 1 minute. Prolongation of the sterilization time associated with dilution was more gradual in comparison to PVP-I solution. CPC sterilized 7 of 10 microbial strains within 3 minutes at 3 mg/100 mL. At 500 mg/100 mL, which is near the upper limit of the concentration that is actually used, PVP-I solution sterilized 7 microbial strains within 3 minutes. However, PVP-I had no sterilization effect when diluted to 100 mg/100 mL or lower. With addition of saliva, PVP-I sterilized 2 microbial strains within 3 minutes at 500 mg/100 mL, whereas CPC solution sterilized 9 microbial strains within 1 minute at 50 mg/100 mL. Our results show that in use influenced by dilution with saliva, CPC is likely to maintain a strong sterilization effect, whereas PVP-I may have a reduced effect.

Exciton interactions in cyanine dye--hyaluronic acid (HA) complex: reversible and biphasic molecular switching of chromophores induced by random coil-to-double-helix phase transition of HA.

Reversible and biphasic switching of monomer-to-R-chiral dimer transition and R-chiral-to-S-chiral dimer transition of cyanine chromophores were demonstrated by complex formation with hyaluronic acid.