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Epidermal growth factor receptor (EGFR) is highly expressed in several types of cancer cells including oral squamous cell carcinoma (OSCC). EGF/EGFR signaling is recognized as an important molecular target in cancer therapy. However, cancer cells often become tolerant to EGF/EGFR signaling-targeted therapies. In the tumor microenvironment, the tumor incites inflammation and the inflammation-derived cytokines make a considerable impact on cancer development. In addition, hyperosmolarity is also induced, but the role of osmotic stress in cancer development has not been fully understood. This study demonstrates molecular insights into hyperosmolarity effect on OSCC development and shows that NFAT5 transcription factor plays an important functional role in enhancing the oral cancer cell proliferation by inducing the EGFR translocation from the endoplasmic reticulum to the plasma membrane through increase the expression of DPAGT1, an essential enzyme for catalyzing the first committed step of N-linked protein glycosylation. These results suggest that hyperosmolarity-induced intra-nuclear translocation of NFAT5 essential for DPAGT1 activation and EGFR subcellular translocation responsible for OSCC tumor progression., This study demonstrates that NFAT5 promotes oral squamous cell carcinoma progression in the hyperosmotic environment through increased expression of DPAGT1, an essential enzyme for protein glycosylation, and altered EGFR subcellular localization from the cytoplasm to the plasma membrane in tumor cells.

Objective For dental students, textbooks and lectures provide basic knowledge, and simulated and actual clinical training provide learning in technical and communication skills. At our college, conservative dentistry is taught in the third and fourth years of a 6‐year undergraduate degree. Clinical training is undertaken subsequently in the fifth year and includes cavity preparation and composite resin filling tasks. However, despite the clinical importance of a full understanding surrounding these procedures, sixth‐year students occasionally provide incorrect answers regarding these procedures in assessments. Although they demonstrated a basic understanding of the procedures, they may have forgotten the acquired knowledge during their clinical training. Therefore, we developed an error‐detection examination to evaluate and improve fifth‐year students' knowledge. Methods Written detailed treatment procedures for standardized, typical, cases were presented to students. Some critical steps were intentionally written incorrectly, and students had to identify and correct these. After correcting the steps, students gave a presentation to their peers on their corrections. This was followed by a summary of the correct answers and a short lecture by the teacher. Students then completed a questionnaire investigating their experience of the examination. Results Students misunderstood some key treatment steps, such as pretreatment of composite resin filling, amalgam removal, and ceramic inlay fitting. The questionnaire revealed that this method of testing applied knowledge was new to students and helped them to identify knowledge gaps. The test also increased their motivation to study conservative dentistry. Students were open to taking similar tests in different areas. Conclusion Although conservative dentistry is a basic field of dental treatment, mistakes in treatment can lead to early treatment failure or reduce the lifetime of a restored tooth. Therefore, students need to have a deep understanding of procedures. Error‐detection examinations may help students identify knowledge gaps and provide useful feedback to teachers to identify areas that they should stress in earlier years.

Objective To investigate associated risk factors for oral candidiasis in elderly patients hospitalized in a community-based acute-care hospital with no dental units. Methods Two hundred and twenty-eight elderly patients (male: 105, female: 123), who were hospitalized with several systemic diseases in a community-based acute-care hospital from May 2014 to October 2016, were retrospectively analysed by multiple logistic regression. Results Multiple logistic regression analysis shows that bacterial pneumonia has a statistically strong relationship with oral candidiasis (p = 0.000, OR: 5.173, 95% CI: 2.368-11.298). The order followed is poor oral hygiene (p = 0.001, OR: 6.095, 95% CI: 2.003-18.545) and severe dry mouth (p = 0.043, OR: 2.507, 95% CI: 1.031-6.098). Other correlated factors including diabetes mellitus, denture wearer, dysphagia, malnutrition, requiring care and use of inhalation steroids, were not statistically significant in this study. Conclusions Bacterial pneumonia correlates with oral candidiasis.

Ameloblastic carcinoma (AC) is defined as a rare primary epithelial odontogenic malignant neoplasm and the malignant counterpart of benign epithelial odontogenic tumor of ameloblastoma (AB) by the WHO classification. AC develops pulmonary metastasis in about one third of the patients and reveals a poor prognosis. However, the mechanisms of AC oncogenesis remain unclear. In this report, we aimed to clarify the mechanisms of malignant transformation of AB or AC carcinogenesis. The relatively important genes in the malignant transformation of AB were screened by DNA microarray analysis, and the expression and localization of related proteins were examined by immunohistochemistry using samples of AB and secondary AC. Two genes of hypoxia‐inducible factor 1 alpha subunit (HIF1A) and zinc finger E‐box‐binding homeobox 1 (ZEB1) were significantly and relatively upregulated in AC than in AB. Both genes were closely related in hypoxia and epithelial‐mesenchymal transition (EMT). In addition, expressions of HIF‐1α and ZEB1 proteins were significantly stronger in AC than in AB. In the cell assays using ameloblastoma cell line, AM‐1, hypoxia condition upregulated the expression of transforming growth factor‐β (TGF‐β) and induced EMT. Furthermore, the hypoxia‐induced morphological change and cell migration ability were inhibited by an antiallergic medicine tranilast. Finally, we concluded that hypoxia‐induced HIF‐1α and ZEB1 were critical for the malignant transformation of AB via TGF‐β‐dependent EMT. Then, both HIF‐1α and ZEB1 could be potential biomarkers to predict the malignant transformation of AB., We aimed to clarify the mechanisms of malignant transformation of ameloblastoma or ameloblastic carcinoma carcinogenesis. We found that hypoxia‐induced HIF‐1a and ZEB1 are critical for the malignant transformation of ameloblastoma via TGF‐beta‐dependent EMT.

We measured the thermal constants (including conductivity, specific heat, and thermal diffusivity) of methane hydrate (MH)–bearing sediment samples recovered in 2015 from the Krishna–Godavari Basin, in India. These samples were recovered through the National Gas Hydrate Program Expedition 02 (NGHP-02). The measurements were performed using the single-sided Transient Plane Source (TPS) method. To investigate the influence of the sediment composition on the thermal properties of MH-bearing sediments, the thermal constants of MH-bearing sediments were measured at 5 °C and 10 MPa over a porosity (ϕ) range of 41% ≤ ϕ ≤ 51% and MH saturation (Sh) range of 17% ≤ Sh ≤ 74%. In addition, density and mineral compositional measurements of the dry sediment grain samples were conducted. The measured thermal conductivity slightly decreases with increasing ϕ and is independent of Sh. The measured specific heat increased with increasing ϕ, whereas it decreased with increasing Sh. The measured thermal diffusivity decreased with increasing ϕ, whereas it increased with increasing Sh. Various models were used to estimate the thermal constants to examine the applicability of these models to natural MH-bearing sediments. The distribution model (using a geometric mean model) is valid from the low to high MH saturations; however, the thermal properties of clay-rich layers are not likely reproducible by the distribution model from the mineral compositions. This indicates that the low value of the observed thermal conductivity in the clay-rich samples is likely a product of the sediment's small grain size.

Contains fulltext : 226388.pdf (Publisher’s version ) (Open Access) We are in the midst of a global transition in which digital "screens" are no longer simply entertainment devices and distractions; rather, adolescents are currently living in a hybrid reality that links digital spaces to offline contexts. Yet, psychological scientists studying the mental health impact of digital experiences largely focus on correlations with "screen time," leading to oversimplified and atheoretical conclusions. We propose an alternative, functional approach to studying adolescent mental health in the digital age, one that examines why and how digital media affect adolescent development. Specifically, we suggest that understanding identity development - the core developmental task of adolescence - can help pinpoint the digital experiences that contribute to healthy versus problematic mental health outcomes. We have four objectives: (1) integrate principles from clinical and personality psychology with developmental theory to present a theoretical framework for investigating narrative identity; (2) show how this framework provides a useful lens for evaluating the impact of digital media on adolescents; (3) suggest a set of novel hypotheses that specify what kinds of digital contexts and experiences lead to healthy versus problematic mental health outcomes; and (4) propose a detailed research agenda that tests these hypotheses. 29 p.

Contains fulltext : 226381.pdf (Publisher’s version ) (Open Access) The current response article began by situating this journal volume in the current COVID-19 pandemic context which has driven young people into digital spaces for far longer periods of time than ever. Many scholars, policy makers, and the public at large are recognizing that these social digital spaces may be the only outlet by which youth and their families can remain safe (at least physically), while also participating in some important social outlets. We discussed the notion of hybrid reality and argued that young people themselves often do not experience their digital and physical contexts as functionally distinct, despite there being good scientific reasons for examining these contexts separately. We then considered whether or not digital activity (at least some) should be considered pathological or inherently unhealthy for young people. Like most of the commentators, we advocated for a nuanced approach and emphasized the importance of a functional, developmental lens. In the second half of our response, we turned to the narrative identity framework itself and clarified misconceptions about what we considered novel about our approach. We found it particularly useful to explain why self-determination theory can be regarded as a constituent of the identity development framework, but that it does not subsume it. We moved on to discuss how the new insights provided by the commentators could be synthesized and suggested directions for new research studies and methodologies. Finally, we ended with an examination of how a more elaborated narrative identity framework offers specific directions for designing new digital interventions for promoting young people’s mental health and wellbeing. It is our hope that the target article with its detailed articulation of the narrative identity framework, together with the thoughtful commentaries and this response, can together inform future research, practice, and policy relevant to digital activity and its impact on young people’s mental health and wellbeing. 13 p.

Professional oral health care (POHC) is known to prevent aspiration pneumonia in patients with dysphagia and/or those at the perioperative stage of surgery. However, the effect of POHC on patients suffering from aspiration pneumonia remains unknown. Here, we report a case where continual POHC intervention improved severe aspiration pneumonia. A 74-year-old male patient with a brain infarction suffered from severe aspiration pneumonia (PSI: IV, A-DROP: 3) complicated by vascular dementia and severe dysphagia. Because an antimicrobial approach following the treatment guidelines for pneumonia was not effective, we started a POHC intervention to improve his poor oral condition at the request of the attending doctor and the patient’s family. The severe pneumonia markedly improved after continual POHC by the dental team. This case suggests that continual POHC intervention by a dental hygienist may improve severe aspiration pneumonia.

Summary The role of macrophage infiltrates in oral mucosal acute graft-versus-host disease (AGVHD) remains unclear, although clinical studies suggest that macrophage infiltration correlates directly with the severity of AGVHD. In this study, we investigated the role of M1 macrophage infiltration in the oral mucosa of rats with AGVHD. Lewis rat spleen cells were injected into (Lewis × Brown Norway) F1 rats to induce systemic GVHD. Tongue samples were evaluated using histology, immunohistochemistry, dual immunofluorescence, real-time reverse transcription–polymerase chain reaction, Transwell migration assays and Stamper–Woodruff binding assays. At the onset of oral mucosal AGVHD, dual immunofluorescence and migration assays revealed that M1 macrophages had accumulated in the basement membrane (BM) region via the laminin/CD29 β1 integrin pathway. Macrophage-secreted matrix metalloproteinase-2 was related to BM degradation. The adhesion of macrophages to the oral epithelium could be inhibited by pretreating macrophages with a CC chemokine receptor 2 (CCR2) antibody and/or pretreating lesion sections with monocyte chemoattractant protein-1 (MCP-1) antibody. Our data show that the migration and adhesion of M1 macrophages are associated with oral mucosal AGVHD, which is mediated in part by both laminin/CD29 β 1 intern and MCP-1/CCR2 pathways. Therefore, our study provides additional support for the contribution of macrophage infiltrate to the development of oral mucosal AGVHD.

Objectives Volume-regulated anion channels (VRACs), expressed in various cells, play an important role in cell volume regulation. Despite being physiologically defined almost half a century ago, only the molecular candidates of VRAC, TMEM16A, LRRC8A, and bestrophin-1 (BEST1), are known. Here, we aimed to explore the functional significance of VRAC in, HST-1, an oral squamous cell carcinoma (OSCC) cell line. Methods Cell proliferation assays, RT-PCR, Western blot, and flow cytometry were used to estimate changes in gene expression and cell proliferation. Ion channel activity was recorded using the patch-clamp technique. Specific genes were knocked-down by siRNA assays. Results VRAC, identified as a hypotonicity-induced current, was highly functional and associated with the proliferation of HST-1 cells but not of HaCaT (a normal keratinocyte) cells. The pharmacological profile of VRAC in HST-1 was similar to that reported previously. DCPIB, a specific VRAC inhibitor, completely inhibited VRAC and proliferation of HST-1 cells, eventually leading to apoptosis. VRAC in HST-1 was attenuated by the knockdown of TMEM16A and LRRC8A, while knockdown of BEST1 affected cell proliferation. In situ proximity ligation assay showed that TMEM16A and LRRC8A co-localized under isotonic conditions (300 mOsM) but were separated under hypotonic conditions (250 mOsM) on the plasma membrane. Conclusions We have found that VRAC acts to regulate the proliferation of human metastatic OSCC cells and the composition of VRAC may involve in the interactions between TMEM16A and LRRC8A in HST-1 cells.

There is an increasing population of elderly patients suffering from Alzheimer’s disease (AD), the most common form of dementia. In dentistry, a critical problem associated with these patients is the use of a new denture, as AD patients often refuse dental management and are disturbed by minor changes in their oral environment. Some AD patients have further complications associated with oral dyskinesia, a movement disorder that can make dental management difficult, including the stability of a complete denture. In this case, we successfully fitted a complete maxillary denture using modified bilateral balanced occlusion after multiple tooth extractions under intravenous sedation in a 66-year-old woman with severe AD complicated by oral dyskinesia. Following treatment, her appetite and food intake greatly improved. Providing a well-fitting complete denture applied by modified bilateral balanced occlusion, which removes lateral interference using zero-degree artificial teeth for movement disorder of the jaw in patients with severe AD complicated by oral dyskinesia, helps improve oral function.

A theoretical investigation from the view point of gas-dynamics and thermodynamics was carried out, in order to clarify the energy separation mechanism in an unconfined laminar compressible vortex, as a primary flow element of a vortex tube. The mathematical solutions of density and temperature in a viscous compressible vortical flow, with tangential velocity, were examined using an evaluation equation of total temperature. It is found from the results that a hotter gas in the peripheral region of the vortex is mainly generated by heat caused by viscous dissipation. A colder gas in the vortex center is mainly generated by viscous shear work done by the fluid element onto the surface of the surrounding gas. In addition, it is also found that the larger the representative Mach number of a vortex is, the lower the total temperature at the center of the vortex is, and at the same time, the higher the maximum total temperature in the peripheral region is. The increase in specific heat ratio of the working gas has the same effect, as increasing the representative Mach number of the vortex, on the total temperature in the vortex.

Background Interactions of resident bacteria and/or their producing lipopolysaccharide (LPS) with sulcular epithelial keratinocytes may be regulated by autophagy in the gingival sulcus. In this study, we investigated an induction of bacterial autophagy in exfoliative sulcular keratinocytes of the gingival sulcus and cultured keratinocytes treated with Porphyromonas gingivalis-originated LPS (PgLPS). Results Exfoliative sulcular keratinocytes showed an induction of autophagy, in addition to increased expression of LPS-mediated factors including lipopolysaccharide-binding protein and toll-like receptors (TLRs), leading to co-localization of bacteria with autophagosomes. In contrast, exfoliative keratinocytes from the free gingiva did not show similar autophagy. Autophagy activity in human cultured keratinocyte cells (HaCaT) was induced by PgLPS, which was dependent partially on the AMP-activated protein kinase (AMPK) pathway via increased intracellular reactive oxygen species (ROS) and was in association with an activation of TLR4 signaling. After incubation of cultured keratinocytes with E.coli BioParticles following PgLPS stimulation, co-localization of bioparticles with autophagosomes was enhanced. Conversely, blockage of autophagy with 3-methyladenin and LPS-binding with polymyxin B led to significant reduction of co-localization of particles with autophagosomes. Conclusion These findings indicate that PgLPS-induced autophagy is at least partially responsible for interaction between bacteria and sulcular keratinocytes in the gingival sulcus.

Both aspiration pneumonia and oral candidiasis are caused by opportunistic infection of intraoral commensals and have many similar risk factors linked to oral health in older adults. Candida albicans forms biofilms with respiratory bacteria such as Klebsiella pneumoniae and Pseudomonas aeruginosa. The aim of our study was to determine the relationship between bacterial pneumonia, including aspiration pneumonia, and oral candidiasis in older patients who were hospitalized with several systemic diseases in a community-based acute care hospital without a dental unit. We retrospectively analyzed 228 older patients (male: 105, female: 123) using multiple logistic regression. The mean age of the patients was 81.3 (SD: 11.1) years. Forty-four patients were oral candidiasis positive, and 78 patients suffered from bacterial pneumonia, including aspiration pneumonia. Results showed that bacterial pneumonia had the strongest statistical relationship with oral candidiasis (p=0.000, OR: 5.173, 95 % CI: 2.368–11.298). This was followed by poor oral hygiene (p=0.001, OR: 6.095, 95 % CI: 2.003–18.545) and severe dry mouth (p=0.043, OR: 2.507, 95 % CI: 1.031–6.098). Other conventional risk factors for oral candidiasis, such as diabetes mellitus, denture wearer, dysphagia, malnutrition, requiring care, use of inhalation steroids, were not statistically significant in this study. Fifteen species of bacteria, including Klebsiella pneumoniae and Pseudomonas aeruginosa, were detected by pharyngeal sputum culture in 24 of 31 patients who were diagnosed with both oral candidiasis and bacterial pneumonia. In conclusion, bacterial pneumonia is a possible new risk factor for oral candidiasis in older adults.

Toothbrushes after use are contaminated by many microorganisms including bacteria, fungi and viruses. We are thinking of making an anti-bacterial toothbrush by including ceramics in the bristle. But if the ceramic-containing bristles are too hard for the tooth and gingiva, it cannot be used as a toothbrush. So, before examining the antibacterial properties, we evaluated the feeling by asking students of dental hygiene. In our preliminary experiment, we determined the most appropriate width and length of ceramic-containing bristles. The students used this toothbrush and answered the questions. Almost all the students were satisfied with the new toothbrush with ceramic-containing bristles. Moreover, the new toothbrush was found to be comparable with the world-wide sold toothbrush. We obtained data that the ceramic-containing bristles were acceptable. Further study to investigate the anti-bacterial properties and effective cleanliness are in progress.

Methods: Approximately 70% of the patients were female and most were in their 40s. We analyzed the possible causes of halitosis. Results: More than half of the patients exhibited a thick tongue coating. Low salivary flow was present in 23.6% of males and in 39.4% of females. Pocket depth ≥6 mm was found in 44.2% of males and in 16.7% of females. We also analyzed treatment provided after breath odor measurement. Most of the patients with physiological halitosis and pseudohalitosis did not receive further treatment, but some were treated at the COD with scaling and professional tooth cleaning. Many of the patients with genuine halitosis received dental treatment at the COD. We referred patients from other clinics and from distant locations to their local doctors for treatment. Conclusion: Halitosis had various causes, and the role of dental hygienists, including scaling, root planing, and tooth brushing instruction, are important in decreasing breath odor. Dental hygienists play an important role in communication with halitosis patients.

In order to clarify the structure of the cold flow discharged from the counter-flow vortex tube (VT), the temperature and pressure of the cold flow were measured, and the existence and behavior of the reversed flow at the cold exit was studied using a simple flow visualization technique consisting of a 0.75mm-diameter needle, and an oil paint droplet. It is observed through this experiment that the Pitot pressure at the cold exit center can either be lower or higher than atmospheric pressure, depending on the inlet pressure and the cold fraction, and that a reversed flow is observed when the Pitot pressure at the cold exit center is lower than atmospheric pressure. In addition, it is observed that when reducing the cold fraction from unity at any arbitrary inlet pressure, the region of reversed and colder flow in the central part of cold exit extends in the downstream direction.

We examined the endothelin-1 (ET-1)-induced increase in the intracellular free Ca(2+) concentration ([Ca(2+)]i) in fura-2-loaded rat pulmonary small arteries. ET-1 (30 nM) elicited a long-lasting increase in [Ca(2+)]i in physiological salt solution (PSS). In subsequent experiments, arteries were pretreated with BQ-788, an ETB-specific blocker, to allow us to focus on responses mediated via the ETA receptor, the existence of which was confirmed by immunohistochemistry. In Ca(2+)-free PSS, ET-1 evoked a small transient increase in [Ca(2+)]i, indicating Ca(2+) release from the SR (sarcoplasmic reticulum). After a switch to PSS (containing 2mM CaCl2), ET-1 elicited a long-lasting increase in [Ca(2+)]i that was not inhibited by 1 μM nicardipine, an L-type Ca(2+)-channel inhibitor, suggesting involvement of a Ca(2+)-influx pathway independent of that channel. In arteries preincubated with 30 μM cyclopiazonic acid (CPA) or 2 μM thapsigargin (TG), the ET-1-induced Ca(2+)-release was greatly reduced, and the induced Ca(2+)-influx was attenuated. U-73122, a phospholipase C (PLC) inhibitor, had inhibitory effects similar to those of CPA and TG on the ET-1-induced Ca(2+)-release and Ca(2+)-influx, whereas U-73343, an inactive analogue of U-73122, had no such effects. Two putative membrane-permeable IP3-receptor blockers, 2-aminoethoxydiphenyl borate (2APB, 50 μM) and Xestospongin C (20 μM), (a) almost completely inhibited the ET-1-induced Ca(2+)-release and Ca(2+)-influx, and (b) reduced the ET-1-induced contraction. These results indicate that in rat pulmonary small arteries, ET-1 induces receptor-operated Ca(2+) influx via the ETA receptor, and that this influx interacts with InsP3-receptor activation.

Volatile sulfur compounds (VSCs) produced by oral anaerobes are the major compounds responsible for oral malodor.Enterococcus faeciumWB2000 is recognized as an antiplaque probiotic bacterium. In this study, the effect ofE. faeciumWB2000 on VSC production byPorphyromonas gingivaliswas evaluated, and the mechanism of inhibition of oral malodor was investigated.P. gingivalisATCC 33277 was cultured in the presence of four lactic acid bacteria, includingE. faeciumWB2000. Subsequently,P. gingivalisATCC 33277, W50, W83, and two clinical isolates were cultured in the presence or absence ofE. faeciumWB2000, and the emission of VSCs from spent culture medium was measured by gas chromatography. The number ofP. gingivalisATCC 33277 in mixed culture withE. faeciumWB2000 decreased at 6 h, and the rate of decrease was higher than that in mixed cultures with the other lactic acid bacteria. The numbers of fiveP. gingivalisstrains decreased at similar rates in mixed culture withE. faeciumWB2000. The concentration of methyl mercaptan was lower in spent culture medium fromP. gingivalisandE. faeciumWB2000 cultures compared with that fromP. gingivalisalone. Therefore,E. faeciumWB2000 may reduce oral malodor by inhibiting the growth ofP. gingivalisand neutralizing methyl mercaptan.

Bisphosphonates and irradiation are useful medical treatments, but can often cause oral complications such as medication-related oral necrosis of the jaw (MRONJ) and osteoradionecrosis (ORN) during oral surgery, including tooth extraction. Therefore, we should take all risks into consideration carefully before choosing dental treatment for patients with a medical history of such therapies. A 55-year-old woman who underwent cord blood transplantation to treat extranodal natural killer T (NK/T) cell lymphoma (nasal type IVB) had a medical history of bisphosphonate and irradiation treatments. We treated her residual tooth root by applying orthodontic extrusion to avoid extraction and successfully restored the tooth. Application of an orthodontic tooth extrusion technique for conservative treatment of a residual tooth is a useful means of avoiding MRONJ or ORN in patients who have a medical history of bisphosphonate and irradiation treatments.

Here, we report a case of oral malodor that was diagnosed by bacterial examination. The patient (a 32-year-old female) visited our breath clinic because a family member advised her to do so. Strong oral malodor was detected by several tests including an organoleptic test, a portable sulfide monitor, and gas chromatography. She noticed her oral malodor, but her motivation toward treatment was low. Even after explaining the cause of halitosis and the importance of oral hygiene, her motivation did not improve. So we applied a bacterial examination, and explained the results in detail. She understood how oral bacteria had caused the oral malodor, and she tried to do tooth brushing better. After a basic periodontal treatment, her oral condition improved and the number of periodontopathic bacteria reduced. She continued with careful tooth brushing even after the periodontal treatment, and her breath odor remarkably decreased. This case report indicates the usefulness of bacterial examination for motivating patients to improve their oral hygiene.

Many people worry about their breath odor, and the importance of halitosis treatment is increasing. Consequently, it is necessary for dental hygienists to obtain a basic knowledge of halitosis. To achieve this, we must improve the motivation of dental hygienist students to acquire such knowledge. To this end, we conducted a questionnaire survey to assess the awareness and knowledge of the problem among dental hygienist students and compared the results of the survey for students in the first and third grades. The percentage of students who perceived the oral malodor of patients was higher in the third grade group. The third graders also placed a greater importance on the participation of dental hygienists in halitosis treatment. Most students in both grades believed that demand for halitosis treatment would increase, although there were students in the first grade that did not hold this view. A similar percentage of students in the two grades were willing to study halitosis, although some first grade students were not at all interested. Many more students in the third grade wanted to take part in halitosis treatment. Student knowledge of halitosis was approximately the same in both grades, but, surprisingly, the third graders gave some incorrect answers in this area. From the results of this study, the third grade students appeared to have higher motivation to study halitosis treatment than the first graders. However, the upper grade students seemed to lack some knowledge, which may be due to the extended time since they had studied the topic at school. It is necessary for us to improve student motivation for studying halitosis and for maintaining their knowledge in order to better perform the treatment of halitosis after the students become dental hygienists.

Oral bacteria are considered to be associated with several systemic diseases. Recently, their association with inflammatory bowel disease (Crohn's disease and ulcerative colitis) and colorectal carcinoma has attracted much attention. In this mini-review, the association of oral bacteria with these diseases is briefly summarized. Fusobacterium nucleatum is known as a periodontopathic bacterium, and it is also associated with inflammatory bowel disease and colorectal carcinoma. Campylobacter concisus, which is found at the site of periodontitis, is associated with inflammatory bowel disease. Streptococcus mutans is a famous cariogenic bacterium, but a highlyvirulent strain of this bacterium is also associated with inflammatory bowel disease. In this way, both periodontopathic bacteria and cariogenic bacteria are associated with bowel diseases. Further epidemiological studies are necessary to reveal the cause and effect relationship between oral bacterial and bowel diseases.

An increasing number of elderly people in Japan are living in nursing homes. Some of them have strong breath odor, which makes it difficult for the facility workers to perform oral care service. A questionnaire survey was conducted to examine how often the facility workers experience the residents’ oral malodor. The knowledge and consciousness of workers about oral malodor were also examined. Some workers actually experienced oral malodor of the facility residents and hoped that their breath odor could be reduced. The workers understood the causes of oral malodor, but the importance of saliva flow was not well recognized. On the other hand, more than 80% of workers expressed concern about their own breath odor while providing oral care. Nearly 80% of them want to get more information on oral malodor. The results of this questionnaire survey showed that oral malodor is an important matter at care facilities for the elderly, and instruction on oral malodor is necessary for facility workers.

To clarify the properties of adenosine triphosphate sensitive K+ channel in human detrusor smooth muscle we examined the effect of the representative nicotinic acid derivatives β-nicotinamide adenine dinucleotide, cyclic adenosine diphosphate ribose and nicotinic acid adenine dinucleotide phosphate (Sigma-Aldrich®) on human detrusor adenosine triphosphate sensitive K+ channels.Patch clamp procedures were done in human detrusor cells. Reverse transcriptase and real-time polymerase chain reaction were performed to clarify the subunit components of adenosine triphosphate sensitive K+ channels.The K+ channel opener levcromakalim induced a long lasting outward current that was inhibited by glibenclamide (Sigma-Aldrich) under the whole cell configuration. The single channel study revealed that the unitary conductance of the adenosine triphosphate sensitive K+ channel in the human detrusor was 11 pS and nucleotide diphosphates increased its open probability. Applying β-nicotinamide adenine dinucleotide also activated the adenosine triphosphate sensitive K+ channel but applying cyclic adenosine diphosphate ribose or nicotinic acid adenine dinucleotide phosphate had little effect on channel activation. Molecular studies indicated that Kir6.1 and SUR2B were the predominant components of the adenosine triphosphate sensitive K+ channel in the human detrusor.To our knowledge we report the first single channel study of the adenosine triphosphate sensitive K+ channel in the human detrusor. The properties of this channel, ie unitary conductance, adenosine triphosphate sensitivity and diphosphate activation, were consistent with those of other smooth muscle organs. β-Nicotinamide adenine dinucleotide has the potency to activate adenosine triphosphate sensitive K+ channels in the human detrusor. This channel likely has some role during ischemic conditions as well as physiological muscle motion leading to the activation of cell metabolism.

The theoretical calculation of a two-stage high-velocity oxy-fuel thermal spray gun was conducted for the purpose of predicting the stagnant pressure in the mixing chamber (MC). The theoretical results were compared with the experimental ones obtained by the cold flow and actual spray gun tests. The effect of the diffuser shape installed between the combustion chamber (CC) and the MC was also investigated in the cold flow test. It was clarified in this study that 1) the theoretical calculation shows that in order to obtain a larger pressure in the MC the diameter rations of d3t/d1t and d1e/d1t should be chosen to satisfy Eq.(11), to keep the diffuser throat unchoked, 2) the theoretical results of p03/p01 agree with the results of cold flow test within an accuracy of 6%, 3) the theoretical results of p01 agree with the results of actual two-stage HVOF gun test within an accuracy of 4%, demonstrating the validity of the present theoretical calculation.

Stretch-activated cation channels (SACs) have been observed in many types of smooth muscle cells. However, the molecular identity and activation mechanisms of SACs remain poorly understood. We report that TRPM4-like cation channels are activated by membrane stretch in rat cerebral artery myocytes (CAMs). Negative pressure (≥20 mmHg, cell-attached mode) activated single channels (approximately 20 pS) in isolated CAMs. These channels were permeable to Na+ and Cs+ and inhibited by Gd3+ (30 µM) and DIDS (100 µM). The effect of negative pressure was abolished by membrane excision, but subsequent application of Ca2+ (>100 nM) to the intracellular side of the membrane restored single channel activity that was indistinguishable from SACs. Caffeine (5 mM), which depletes SR Ca2+-stores, first activated and then abolished SACs. Tetracaine (100 µM), a ryanodine receptor antagonist, inhibited SACs. Overexpression of hTRPM4B in HEK293 cells resulted in the appearance of cation channels that were activated by both negative pressure and Ca2+ and which had very similar biophysical and pharmacological properties as compared with SACs in CAMs. These studies indicate that TRPM4-like channels in CAMs can be activated by membrane stretch, possibly through ryanodine receptor activation, and this may contribute to the depolarization and concomitant vasoconstriction of intact cerebral arteries following mechanical stimulation. Keywords:: TRPM4, stretch, cation channel, cerebral artery, smooth muscle

Ameloblastoma is the most common benign odontogenic tumor in Japan. It is believed that it expands in the jaw bone through peritumoral activation of osteoclasts by receptor activator of nuclear factor kappa-B ligand (RANKL) released from the ameloblastoma, as in bone metastases of cancer cells. However, the clinical features of ameloblastoma, including its growth rate and patterns of invasion, are quite different from those of bone metastasis of cancer cells, suggesting that different underlying mechanisms are involved. Therefore, in the present study, we examined the possible mechanisms underlying the invasive expansion of ameloblastoma in the jaw bone. Expression levels of RANKL assessed by western blotting were markedly lower in ameloblastoma (AM-1) cells than in highly metastatic oral squamous cell carcinoma (HSC-3) cells. Experiments coculturing mouse macrophages (RAW264.7) with AM-1 demonstrated low osteoclastogenic activity, as assessed by tartrate-resistant acid phosphatase (TRAP)-positive multinuclear cell formation, probably because of low release of RANKL, whereas cocultures of RAW264.7 with HSC-3 cells exhibited very high osteoclastogenic activity. Thus, RANKL release from AM-1 appeared to be too low to generate osteoclasts. However, AM-1 cultured directly on calcium phosphate-coated plates formed resorption pits, and this was inhibited by application of bafilomycin A1. Furthermore, vacuolar-type H+-ATPase (V-ATPase) and H+/Cl- exchange transporter 7 (CLC-7) were detected on the surface of AM-1 cells by plasma membrane biotinylation and immunofluorescence analysis. Immunohistochemical analysis of clinical samples of ameloblastoma also showed plasma membrane-localized V-ATPase and CLC-7 in the epithelium of plexiform, follicular and basal cell types. The demineralization activity of AM-1 was only 1.7% of osteoclasts demineralization activity, and the growth rate was 20% of human normal skin keratinocytes and HSC-3 cells. These results suggest that the slow expansion of several typical types of ameloblastomas in jaw bone is attributable to its slow growth and low demineralization ability.

Local blood flow is critically determined by the arterial tone in which sustained Ca(2+) influx, activated by a variety of mechanisms, plays a central regulatory role. Recent progress in molecular biological research has disclosed unexpectedly diverse and complex facets of Ca(2+) entry channel molecules involved in this Ca(2+) influx. Candidates include several transient receptor potential (TRP) superfamily members such as TRPC1, TRPC4, TRPC6, TRPV2, TRPV4 and TRPM4, none of which exhibit simple properties attributable to a single particular role. Rather, they appear to be multimodally activated or modulated by receptor stimulation, temperature, mechanical stress or lipid second messengers generated from various sources, and may be involved in both acute vasomotor control and long-term vascular remodelling. This paper provides an overview of existing knowledge of TRP proteins, and their possible relationships with principal factors regulating the arterial tone (i.e., autonomic nerves, various autocrine and paracrine factors, and intravascular pressure).

We investigated the possible involvement of the melastatin family protein TRPM7 in Ca2+-mediated proliferative control of human retinoblastoma (RB) cells. The growth of RB cell was facilitated by elevating the extracellular Ca2+ concentration with a parallel increase in the magnitude of spontaneous Ca2+ influx. Under nystatin-perforated voltage-clamp, RB cells exhibited an outward-rectifying, spontaneous cation current (Ispont) having Ca2+/Mg2+-inhibited but -permeating properties. Various cation channel blockers inhibiting Ispont (Gd3+, La3+, LOE908, 2-APB) suppressed the spontaneous Ca2+ influx and decelerated the growth of RB cells with similar efficacies. Excision of the RB cell membrane (inside-out) into MgATP-free solution induced a 70pS single channel activity, which was effectively inhibited by millimolar concentrations of Mg2+ or MgATP. RT-PCR and immunocytochemical experiments revealed the expression of TRPM7 mRNA and protein in RB cells, and heterologous expression of TRPM7 in HEK293 cells reproduced the key features of Ispont. In contrast, elimination of this protein from RB cells by siRNA silencing markedly reduced Ispont density and the magnitude of spontaneous Ca2+ influx, which was paralleled by decreased TRPM7 immunoreactivity, decelerated cell proliferation, and retarded G1/S cell cycle progression. These results suggest a significant regulatory role of TRPM7 for RB cell proliferation as a spontaneously activated Ca2+ influx pathway. Keywords:: cell proliferation, basal Ca2+ influx, transient receptor potential protein, melastatin family

1. Pharmacological properties of nifedipine-insensitive, high voltage-activated Ca(2+) channels in rat mesenteric terminal arteries (NICCs) were investigated and compared with those of alpha1E and alpha1G heterologously expressed in BHK and HEK293 cells respectively, using the patch clamp technique. 2. With 10 mM Ba(2+) as the charge carrier, rat NICCs (unitary conductance: 11.5 pS with 110 mM Ba(2+)) are almost identical to those previously identified in a similar region of guinea-pig, such as in current-voltage relationship, voltage dependence of activation and inactivation, and divalent cation permeability. However, these properties are considerably different when compared with alpha1E and alpha1G. 3. SNX-482(200 nM and sFTX3.3 (1 micro M), in addition to omega-conotoxin GVIA (1 micro M) and omega-agatoxin IVA (100 nM), were totally ineffective for rat NICC currents, but significantly suppressed alpha1E (by 82% at 200 nM; IC(50)=11.1 nM) and alpha1G (by 20% at 1 micro M) channel currents, respectively. A non-specific T-type Ca(2+) channel blocker nimodipine (10 micro M) differentially suppressed these three currents (by 40, 3 and 85% for rat NICC, alpha1E and alpha1G currents, respectively). 4. Mibefradil, the widely used T-type channel blocker, almost equally inhibited rat NICC and alpha1G currents in a voltage-dependent fashion with similar IC(50) values (3.5 and 0.3 micro M and 2.4 and 0.14 micro M at -100 and -60 mV, respectively). Furthermore, other organic T-type channel blockers such as phenytoin, ethosuximide, an arylpiperidine derivative SUN N5030 (IC(50)=0.32 micro M at -60 mV for alpha1G) also exhibited comparable inhibitory efficacies for NICC currents (inhibited by 22% at 100 micro M; IC(50)=27.8 mM; IC(50)=0.53 micro M, respectively). 5. These results suggest that despite distinctive biophysical properties, the rat NICCs have indistinguishable pharmacological sensitivities to many organic blockers compared with T-type Ca(2+) channels.

We investigated the receptor-mediated regulation of nifedipine-insensitive, high voltage-activated Ca(2+) currents in guinea-pig terminal mesenteric arterioles (I(mVDCC)) using the whole-cell clamp technique. Screening of various vasoactive substances revealed that ATP, histamine and substance P exert modulatory effects on I(mVDCC). The effects of ATP on I(mVDCC) after complete P2X receptor desensitization exhibited a complex concentration dependence. With 5 mM Ba(2+), ATP potentiated I(mVDCC) at low concentrations (approximately 1-100 microM), but inhibited it at higher concentrations (100 microM). The potentiating effects of ATP were abolished by suramin (100 microM) and PPADS (10 microM) and by intracellular application of GDPbetaS (500 microM), whereas a substantial part of I(mVDCC) inhibition by milimolar concentrations of ATP remained unaffected; due probably to its divalent cation chelating actions. In divalent cation-free solution, I(mVDCC) was enlarged and underwent biphasic effects by ATPgammaS and ADP, while 2-methylthio ATP (2MeSATP) exerted only inhibition, and pyrimidines such as UTP and UDP were ineffective. ATP-induced I(mVDCC) potentiation was selectively inhibited by anti-Galpha(s) antibodies or protein kinase A (PKA) inhibitory peptides and mimicked by dibutyryl cAMP. In contrast, ATP-induced inhibition was selectively inhibited by Galpha(q/11) antibodies or protein kinase C (PKC) inhibitory peptides and mimicked by PDBu. Pretreatment with pertussis toxin was ineffective. The apparent efficacy for I(mVDCC) potentiation with PKC inhibitors was: ATPgammaSATP/=ADP and for inhibition with PKA inhibitors was: 2MeSATPATPgammaSATPADP. Neither I(mVDCC) potentiation nor inhibition showed voltage dependence. These results suggest that I(mVDCC) is multi-phasically regulated by external ATP via P2Y(11)-resembling receptor/G(s)/PKA pathway, P2Y(1)-like receptor/G(q/11)/PKC pathway, and metal chelation.

We investigated the effects of the novel gastroprokinetic agent Z-338 (N-(N-N'-diisopropylaminoethyl)-[2-(2-hydroxy-4,5-dimethoxybenzoylamino)-1,3-thiazole-4-yl] carboxyamide monohydrochloride trihydrate) on L-type voltage-dependent Ca2+ currents (ICa) in guinea pig gastric myocytes by using the whole-cell patch clamp technique. Bath-applied acetylcholine (ACh) produced biphasic effects on ICa, i.e., enhancement (1-100 nM) and inhibition (1-100 microM), both of which were abolished by pretreatment with atropine (10 microM) or intracellular perfusion of GDPbetaS (500 microM). Z-338 (> or = 1 nM, ED50: 120 nM) mimicked the enhancing effects of ACh, but did not inhibit ICa. The effects of Z-338 and ACh were non-additive and blocked by atropine and GDPbetaS, but not by pertussis toxin (PTX) pretreatment (500 ng/ml). ACh (> or = 1 microM) induced slow inward currents via activation of the muscarinic receptor/PTX-sensitive G-protein pathway, but Z-338 was devoid of these effects. Neither pirenzepine (1 microM), AF-DX116 (1 microM), nor oxybutynin (100 nM) could prevent Z-338 (1 microM) and ACh (10 nM) from enhancing ICa, whilst 4-DAMP (100 nM) blocked the effects of Z-338 and ACh. Bath-application of protein kinase C (PKC) activator PDBu (phorbol-12,13-dibutyrate) (250 nM) enhanced ICa, and conversely, pipette inclusion of PKC inhibitor peptide (150 microM) abolished the effects of ACh and Z-338 on ICa. These results collectively suggest that although contribution of the M3 receptor is not excluded, the major actions of Z-338 on gastric myocytes are potentiation of ICa through activation of M5-like receptor.