Measurement of bristle splaying of toothbrushes using digital imaging and evaluation of plaque removal efficacy over 3 months: A randomized controlled trial (RCT).

OBJECTIVE: The aim of this study was to develop an objective method to assess the degree of bristle splaying of used manual toothbrushes and to investigate their plaque removal efficacy. METHODS: A randomized controlled trial targeting Hiroshima University students was performed to assess the plaque removal efficacy of polybutylene terephthalate (PBT) manual toothbrushes. Participants were randomly assigned to the soft toothbrush group (n = 40) or the medium toothbrush group (n = 40). A small number of participants discontinued the intervention for personal reasons in both the medium (n = 6) and soft (n = 2) toothbrush groups. Toothbrushes were collected immediately after first use (T0: baseline), after 1 month of use (T1: month 1), after 2 months of use (T2: month 3) and after 3 months of use (T3: month 6), following the allocation of a new toothbrush. The bristle surface area was measured using digital software. RESULTS: The surface area of the bristles was significantly greater at T1, T2 and T3 than at T0 in the medium toothbrush group (n = 34) and soft toothbrush group (n = 38) (P < .001). Importantly, plaque removal efficacy, calculated from a modified plaque control record score and modified patient hygiene performance score, was significantly lower at T2 than at T0 in both groups. CONCLUSIONS: Our method for evaluation of bristle splaying is considered to be reliable and reproducible. PBT toothbrushes may become less effective after two months of use.

Impairment of tissue repair in pneumonia due to ß-cell deficiency: role of endoplasmic reticulum stress in alveolar macrophages.

OBJECTIVE: Diabetes mellitus (DM) patients are susceptible to delayed resolution of pneumonia. However, the pathogenesis of the impaired tissue repair in inflamed lungs in diabetic patients is unknown. We evaluated phagocytosis of apoptotic cells (efferocytosis), hepatocyte growth factor (HGF) production in bronchoalveolar lavage fluid (BALF), and lung histology in the resolution phase following acute lung injury in streptozotocin (STZ)-induced ß-cell-depleted hyperglycemic mice. We also investigated efferocytosis and HGF production by macrophages under ß-cell depletion condition ex vivo. RESULTS: In ß-cell-depleted mice, efferocytosis was not significantly different from that in control mice; however, the concentration of HGF in BALF was decreased. In addition, diminished HGF production by alveolar macrophages and DNA synthesis in the alveolar epithelium was observed by immunohistochemistry. Ex vivo experiments confirmed that HGF production by macrophages was impaired under ß-cell depletion probably because of endoplasmic reticulum stress.

Association of Oral Function With Long-Term Participation in Community-Based Oral Exercise Programs in Older Japanese Women: A Cross-Sectional Study.

BACKGROUND: There are several researches demonstrating that community-based educational and exercise programs can improve oral function in older people. However, the relationship between oral function and long-term participation in health programs has not been fully elucidated. The objective of this study was to clarify the oral health status and oral function of older people (≥ 65 years) who had been participating in community-based exercise programs at community salons. METHODS: We enrolled 108 women (mean age: 77.6 ± 5.7 years) who participated in oral and physical exercise programs once a week at community salons in Takehara throughout May 2017. This cross-sectional pilot study was approved by the Ethical Committee of Hiroshima University and informed consent was obtained from all participants. To assess oral function, the following tests were performed: tongue pressure test, oral diadochokinesis (ODK) measurement, repetitive saliva swallowing test (RSST) and oral wetness measurement. RESULTS: A significant negative correlation was found between age and ODK or RSST (Spearman's rank correlation; P = 0.007 and P = 0.01, respectively). The duration of participation ranged widely from 1 month to 7 years (median: 2.3 years). Although there was no significant difference between participation period and oral function, individuals who had been participating for 3 years or longer did not demonstrate a negative relationship between age and oral wetness. Furthermore, they exhibited a weaker negative relationship between age and oral function (i.e. tongue pressure, ODK and RSST) when compared with individuals who had been participating for less than 3 years. CONCLUSIONS: Our results suggest that long-term participation in community salon exercise programs may suppress the deterioration of oral function in older people. Further study will be necessary to clarify the significant correlation between oral function and community-based social activities such as oral exercise.

Self-check with plaque disclosing solution improves oral hygiene in schoolchildren living in a children's home.

BACKGROUND: The effectiveness of an oral hygiene program for children living in a children's home has been reported. However, to the best of our knowledge, no studies have evaluated the possible effects of self-checking of oral health among children residing in a children's home. The objective of this study was to examine if self-checking using plaque disclosing solution improves oral hygiene in schoolchildren living in a children's home. METHODS: We enrolled nine schoolchildren (six girls) without untreated decayed teeth living in a children's home in Japan. This preliminary study was designed as a 5-month program comprising group and individual instructions and self-checking using plaque disclosing solution. Paired t-test and Wilcoxon signed-rank test were used for statistical analysis to evaluate the change of Plaque Control Record (PCR) and Patient Hygiene Performance (PHP). RESULTS: The mean PCR significantly decreased to 38.7% after 3 months of self-checking using disclosing solution compared with that before self-checking (i.e., at 1 month) (60.7%) (P < 0.01). PHP score significantly decreased to 1.4 at 4 months compared with that at baseline (2.8) and at 1 month (2.7) (P = 0.012 and P = 0.018). Improvement of oral hygiene status was evaluated according to the ratio of PCR at 4 months to that at 1 month. The average improvement ratio was 0.4 ± 0.35 (range: 0.0-1.0). Significant correlation was not found between improvement rate and school grade (r = 0.63, P = 0.070). CONCLUSIONS: Our results suggest that self-checking with disclosing solution may be effective in improving oral hygiene among schoolchildren at a children's home.

In vivo Magnetic Resonance Microscopy and Hypothermic Anaesthesia of a Disease Model in Medaka.

In medical and pharmacological research, various human disease models in small fish, such as medaka (Oryzias latipes), have been created. To investigate these disease models noninvasively, magnetic resonance imaging (MRI) is suitable because these small fish are no longer transparent as adults. However, their small body size requires a high spatial resolution, and a water pool should be avoided to maximize the strength of MRI. We developed in vivo magnetic resonance microscopy (MR microscopy) without a water pool by combining hypothermic anaesthesia and a 14.1 T MR microscope. Using in vivo MR microscopy, we noninvasively evaluated the hepatic steatosis level of a non-alcoholic fatty liver disease model in medaka and followed the individual disease progression. The steatosis level was quantified by the MRI-estimated proton density fat-fraction (MRI-PDFF), which estimates the triglyceride fat concentration in liver tissue and is recognized as an imaging biomarker. The MRI-PDFF results agreed with a histological analysis. Moreover, we optimized the hypothermic anaesthesia procedure to obtain a recovery proportion of 1 in the experiment involving MR microscopy. Recovered medaka could not be distinguished from naïve medaka after the experiment. Therefore, the in vivo MR microscopy will expand the possibilities of a human disease model in fish.

The green tea polyphenol (-)-epigallocatechin gallate precipitates salivary proteins including alpha-amylase: biochemical implications for oral health.

Green tea is a popular drink throughout the world, and it contains various components, including the green tea polyphenol (-)-epigallocatechin gallate (EGCG). Tea interacts with saliva upon entering the mouth, so the interaction between saliva and EGCG interested us, especially with respect to EGCG-protein binding. SDS-PAGE revealed that several salivary proteins were precipitated after adding EGCG to saliva. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) peptide mass fingerprinting indicated that the major proteins precipitated by EGCG were alpha-amylase, S100, and cystatins. Surface plasmon resonance revealed that EGCG bound to alpha-amylase at dissociation constant (K(d)) = 2.74 × 10(-6) M, suggesting that EGCG interacts with salivary proteins with a relatively strong affinity. In addition, EGCG inhibited the activity of alpha-amylase by non-competitive inhibition, indicating that EGCG is effective at inhibiting the formation of fermentable carbohydrates involved in caries formation. Interestingly, alpha-amylase reduced the antimicrobial activity of EGCG against the periodontal bacterium Aggregatibacter actinomycetemcomitans. Therefore, we considered that EGCG-salivary protein interactions might have both protective and detrimental effects with respect to oral health.

[Functional model of the middle ear ossicles].

In students' dissection practice, it is very difficult to teach students the structures and functions of the middle ear ossicles. The middle ear ossicles are too small to explain their structures and functions. Models are useful in explaining these points, but there have been no models that accurately explain the movements of the middle ear ossicles and the functions of the muscles in the middle ear. This time, we have made a model of middle ear ossicles. Our ear ossicles are made of paper-mache with metal in it. The incudomalleolar and incudostapedial articulations are made of rubber. The tensor tympani and the stapedius muscles are made of wire and the two wires can be fixed by cord stoppers. Our model explains clearly the following mechanisms of the middle ear ossicles. 1. The mechanism of sound conduction system. When the sound vibrates the tympanic membrane, malleus and incus rotate together. The long process of the incus pushes the head of the stapes. The sound is amplified by leverage. 2. Attenuation of sound by contractions of tensor tympani and stapedius muscles. When a loud sound is transmitted through the ossicular system, the tensor tympani muscle pulls the malleus inward while the stapedius muscle pulls the stapes outward. These two forces oppose each other and increase rigidity of the ossicular system, thus reducing the ossicular conduction. 3. The mechanism of how paralysis of stapedius muscle, caused by an injury to the facial nerve, results in hyperacusis. 4. This model also suggests a possible reason why the pars lucida of the tympanic membrane exists.

[A case of rhabdomyolysis associated with Kaposi's varicelliform eruption].

Kaposi's varicelliform eruption is a common disease for dermatologists. In general, it is caused by Herpes simplex virus-1 (HSV-1) infection to skin which is affected by atopic dermatitis. There are some case reports which document a relationship between rhabdomyolysis and virus infection, in those cases, the major pathogenic virus of rhabdomyolysis is a influenza virus. It is exceedingly rare that rhabdomyolysis is caused by Herpes simplex virus. We introduce a case of rhabdomyolysis associated with Kaposi's varicelliform eruption induced by HSV-1. It was localized in the iliopsoas muscles. Since severe rhabdomyolysis may induce fatal acute renal failure, it is important to recognize that rhabdomyolysis can complicate Herpes simplex virus infection.

Essential contribution of monocyte chemoattractant protein-1/C-C chemokine ligand-2 to resolution and repair processes in acute bacterial pneumonia.

Neutrophil infiltration is the first step in eradication of bacterial infection, but neutrophils rapidly die after killing bacteria. Subsequent accumulation of macrophage lineage cells, such as alveolar macrophages (AMs), is essential to remove dying neutrophils, which are a source of injurious substances. Macrophage lineage cells can promote tissue repair, by producing potential growth factors including hepatocyte growth factor (HGF). However, it remains elusive which factor activates macrophage in these processes. Intratracheal instillation of Pseudomonas aeruginosa caused neutrophil infiltration in the airspace; subsequently, the numbers of total AMs and neutrophil ingested AMs were increased. Bronchoalveolar lavage (BAL) fluid levels of monocyte chemoattractant protein (MCP)-1/CC chemokine ligand-2 (CCL2), a potent macrophage-activating factor, were increased before the increases in the number of AM ingesting neutrophils and HGF levels in BAL fluid. Immunoreactive MCP-1 proteins were detected in alveolar type II epithelial cells and AMs only after P. aeruginosa infection. The administration of anti-MCP-1/CCL2 Abs reduced the increases in the number of AM-ingesting neutrophils and HGF levels in BAL fluid, and eventually aggravated lung tissue injury. In contrast, the administration of MCP-1/CCL2 enhanced the increases in the number of AM ingesting neutrophils and HGF levels in BAL fluid, and eventually attenuated lung tissue injury. Furthermore, MCP-1/CCL2 enhanced the ingestion of apoptotic neutrophils and HGF production by a mouse macrophage cell line, RAW 267.4, in a dose-dependent manner. Collectively, MCP-1/CCL2 has a crucial role in the resolution and repair processes of acute bacterial pneumonia by enhancing the removal of dying neutrophils and HGF production by AMs.

Oral findings in Noonan syndrome: report of a case.

Oral findings in a case of Noonan syndrome in an 8-year-old Japanese male are reported. Examination of the patient revealed a narrow, high-arched palate and an anterior open bite. Cephalometric measurements showed a wide gonial angle, a large mandibular plane angle, a large Y-axis and long facial height. It is suggested that the patient had a skeletal open-bite malocclusion, which included an abnormal swallowing habit.