Antimicrobial effect of oral care gel containing hinokitiol and 4-isopropyl-3-methylphenol against intraoral pathogenic microorganisms.

OBJECTIVE: Deterioration of oral hygiene is closely related to an increase in severity and mortality of corona virus disease-19 (COVID-19), and also contributes to the development of various diseases such as aspiration pneumonia or Alzheimer's. Oral care is attracting high interest in Japan, which has entered a super-aging society. In this study, we aimed to investigate whether commercially available Hinora® (HO), an oral care gel containing hinokitiol and 4-isopropyl-3-methylphenol (IPMP), has biofilm formation inhibitory and antimicrobial activities against various intraoral pathogen microorganisms. METHOD: Candida species, Aggregatibacter actinomycetemcomitans, Staphylococcus aureus, and Pseudomonas aeruginosa were selected during the study period, all of which were analyzed using antimicrobial disc, microorganism turbidity, and crystal violet assays. In addition, the germ tube test using Candida albicans (C. albicans) was performed with a modification of Mackenzie's method. Images for morphological observation of the germ tubes were acquired using an inverted microscope. For comparison between products, we used Refrecare® (RC), which only contains hinokitiol (not containing IPMP). RESULTS: All the intraoral pathogenic microorganisms showed drug susceptibility against undiluted forms of HO and/or RC. In particular, HO was more effective at lower concentrations than RC. In the HO-added group, inhibition circles were observed in all bacteria except P. aeruginosa when added at a concentration of 0.5 g/mL or more. The optical density values at 590 nm (crystal violet) and/or 600 nm (microorganism turbidity) of all the fungi and bacteria were significantly lower when cultured in medium with HO. Inhibition of growth or biofilm formation was observed when HO was added at a concentration of 0.05 g/mL or higher. To investigate the action mechanism of HO, germ tube tests were performed in C. albicans. The results showed that culturing C. albicans in soybean-casein digest broth with HO (0.05 g/mL) significantly suppressed germ tube formation. CONCLUSIONS: These data suggest that oral care gel-containing hinokitiol and IPMP has strong biofilm formation inhibitory activity, as well as antifungal and antimicrobial effects against Candida fungi and multiple intraoral pathogenic microorganisms. Therefore, it may be a promising treatment option for oral infections.

Communication training for pharmacy students with standard patients using artificial intelligence.

INTRODUCTION: The objective structured clinical examination (OSCE) is among validated approaches used to assess clinical competence through structured and practical evaluation. Most studies of OSCE have used standardized patients (SPs). However, to our knowledge, there is limited information regarding the specific communication skills enhanced by providing communication training (CT) with SPs. Recently, an artificial intelligence (AI) technology was developed. The aim of this study was to evaluate the experience and outcomes of CT with SPs and impact of using AI for this training. METHODS: This study targeted fourth-year students participating in a pre-learning course for pharmacy practice experience offered at a Japanese university in 2020. The ENcode, Decode, Control, and REgulate model, which evaluates 24 communication skills, was utilized as a questionnaire-based survey. The survey was conducted prior to CT, following CT, and after a second CT session six weeks later with AI. RESULTS: Seven skills, namely "desire suppression," "expectation acceptance," "facial expression," "emotional communication," "dominance," "maintaining relationships," and "dealing with disagreements," were enhanced by the CT with SPs. These skills were included in the broad categories of "management" and "expression" skills. They were not significantly enhanced by following AI training. However, differences observed between the students who underwent AI training and those who did not demonstrated a positive effect in almost all skills, suggesting that AI training can enhance certain skills. CONCLUSIONS: CT with SPs enhances students' "management" and "expression" skills. Additionally, AI shows potential for improving the effect of CT.

Study on the Optimal Conditions for Long-term Storage of Melatonin Powder as an In-hospital Preparation.

Melatonin is often prescribed to children with epilepsy. It is supplied as an in-hospital preparation in Japan, but information on the storage conditions of such formulations is lacking. In this study, we used an analytical method to perform periodic measurements in order to establish expiration periods and storage conditions for compounded melatonin powder. A dispenser was used to envelop compounded melatonin powder in wrapping paper, after which the powders were preserved in 1) an opened transparent plastic bag, 2) a closed opaque plastic bag, 3) a closed transparent plastic bag with a desiccant, and 4) a closed opaque plastic bag with a desiccant. The bags were then stored at room temperature (15°C to 25°C), in a refrigerator (4°C), and in a freezer (-20°C). Chromatographic analysis was performed using an ODS-C18 column (40°C, ? = 210 nm) with a mobile phase consisting of methanol: 0.1 M sodium phosphate buffer (55:45, v/v) at a flow rate of 1 mL/min. The measurements were made at the following time points: 0 days, 7 days, 14 days, 28 days (1 month), 56 days (2 months), 84 days (3 months), 112 days (4 months), 140 days (5 months), and 168 days (6 months). The residual rates of melatonin for all time points, at all temperatures, under all conditions exceeded 95%. These experimental data suggested that the melatonin powder is stable for at least 6 months at room temperature of 15°C to 25°C.

Identification and characterization of a brilliant yellow pigment produced by Bordetella pertussis.

Culture supernatants of Bordetella pertussis are a brilliant yellow; however, the structure and biological role of the responsible pigment have not been investigated. In this study, a brilliant yellow-colored fraction was extracted from culture supernatants of B. pertussis and analyzed by HPLC. UV-visible spectral analysis and mass spectrometry identified the brilliant yellow pigment as riboflavin. Riboflavin production was high in lag and early log phases and riboflavin was found to enhance growth of B. pertussis in low-density cultures. Riboflavin production is not regulated by the BvgAS system. In addition, it was found that other Bordetella species, such as B. parapertussis, B. holmesii and B. bronchiseptica, also release riboflavin into their culture supernatants. This is the first report that B. pertussis secrets riboflavin to the extracellular space and that riboflavin may promote its growth. The mechanism may be associated with pathogenesis of B. pertussis.

Development of vaccines against pertussis caused by Bordetella holmesii using a mouse intranasal challenge model.

Bordetella holmesii is recognized as the third causative agent of pertussis (whooping cough) in addition to Bordetella pertussis and Bordetella parapertussis. Pertussis caused by B. holmesii is not rare around the world. However, to date, there is no effective vaccine against B. holmesii. We examined the protective potency of pertussis vaccines available in Japan and vaccines prepared from B. holmesii. A murine model of respiratory infection was exploited to evaluate protective potency. No Japanese commercial pertussis vaccines were effective against B. holmesii. In contrast, a wBH vaccine and an aBH vaccine prepared from B. holmesii were both protective. Passive immunization with sera from mice immunized with aBH vaccine established protection against B. holmesii, indicating that B. holmesii-specific serum antibodies might play an important role in protection. Immuno-proteomic analysis with sera from mice immunized with aBH vaccine revealed that the sera recognized a BipA-like protein of B. holmesii. An aBH vaccine prepared from a BipA-like protein-deficient mutant strain did not have a protective effect against B. holmesii. Taken together, our results suggest that the BipA-like protein plays an important role in the protective efficacy of aBH vaccine.