Use of ATP Bioluminescence Assay to Evaluate Oral Streptococci.

The statistical correlation between the number of oral streptococci and the results of ATP bioluminescence assay was examined and compared with the results from Streptococcus plate counts and an oral bacteria quantification system. Because a significant correlation was found between ATP (RLU) and the number of bacteria in the oral bacteria quantification system for all seven types of oral streptococci examined, ATP would reflect a conditions of oral hygiene. However, using this assay, it was observed it may be difficult to correctly evaluate bacteria that form aggregates. Furthermore, even a small number of bacteria (below 105 CFU/mL) , which cannot be measured by the oral bacteria quantification system, could be estimated by using ATP bioluminescence assay. It was suggested that this assay could be used for quantitative evaluation of the effect of oral cleaning.

Protective effects of resveratrol against 5-fluorouracil-induced oxidative stress and inflammatory responses in human keratinocytes.

Although 5-fluorouracil (5-FU) is currently used as an anti-cancer chemotherapy, adverse effects such as oral mucositis potentially limit its clinical application. Additionally, the prevention of 5-FU-induced side effects are scarce. Resveratrol is known to decrease oxidative damage and inflammation. In this study, we examined the protective effects of resveratrol on 5-FU-induced oxidative stress and inflammatory responses in normal human keratinocytes (HaCaT cell) as in vitro oral mucositis model. HaCaT cells were exposed to 5-FU and simultaneously treated with resveratrol. The effects of resveratrol on 5-FU-induced cytotoxicity were evaluated using cell viability assay. The production of reactive oxygen species (ROS) was measured using a fluorescence spectrophotometer. The effects of resveratrol on nuclear factor erythroid 2-related factor 2 (Nrf2), silent information regulator transcript-1 (SIRT-1), and nuclear factor kappa B (NF-κB) signaling and inflammatory cytokine expression were examined. Resveratrol suppressed 5-FU-induced overproduction of ROS by upregulating anti-oxidant defense genes through Nrf2 activation and SIRT-1 expression. Concerning inflammatory responses, resveratrol suppressed the 5-FU-induced expression of pro-inflammatory cytokines via NF-κB nuclear translocation. Conversely, N-acetylcysteine reduced ROS levels without affecting the expression of pro-inflammatory cytokines. Resveratrol might be useful for preventing 5-FU-induced adverse effects by activating anti-oxidant and anti-inflammatory responses.

Membrane fusion of phospholipid bilayers under high pressure: Spherical and irreversible growth of giant vesicles.

Membrane fusion of giant vesicles (GVs) for binary bilayers of unsaturated phospholipids, dioleoylphosphatidyl-ethanolamine (DOPE) having an ability to promote membrane fusion, and its homolog dioleoylphosphatidylcholine (DOPC) having an ability to form GV, was investigated under atmospheric and high pressure. While DOPC formed GVs in the presence of inorganic salts with a multivalent metal ion under atmospheric pressure, an equimolar mixture of DOPE and DOPC formed GVs both in the absence and the presence of LaCl3. We examined the change in size and shape of the GVs of this binary mixture in the absence and presence of LaCl3 as a function of time under atmospheric and high pressure. The size and shape of the GVs in the absence of LaCl3 under atmospheric and high pressure and those in the presence of LaCl3 under atmospheric pressure hardly changed with time. By contrast, the GV in the presence of LaCl3 under high pressure gradually changed in the size and shape with time on a time scale of several hours. Namely, the GV became larger than the original GV due to accelerated membrane fusion and its shape became more spherical. This pressure-induced membrane fusion was completely irreversible, and the growth rate was correlated with the applied pressure. The reason for the GV growth by applying pressure was considered on the basis of thermodynamic phase diagrams. We concluded that the growth is attributable to a closer packing of lipid molecules in the bilayer resulting from their preference of smaller volumes under high pressure. Furthermore, the molecular mechanism of the pressure-induced membrane fusion was explored by observing the fusion of two GVs with almost the same size. From their morphological changes, we revealed that the fusion is caused by the actions of Laplace and osmotic pressure.

Efficacy of xanthine oxidase inhibitor for chronic kidney disease patients with hyperuricemia.

BACKGROUND: Hyperuricemia is a known risk factor for end-stage renal disease. Although xanthine oxidase (XO) inhibitors are expected to protect the kidney function, evidence to this end is insufficient at present. METHODS: This study was a multi-center, open-labeled, randomized study conducted in Mie Prefecture in Japan. Patients were included if they were between 20 and 80 years old and had a serum uric acid (sUA) level ≥ 7.0 mg/dl with or without gout, estimated glomerular filtration rate (eGFR) of 15-60 ml/min/1.73 m2, and urinary protein creatinine ratio (uPCR) of 0.15-3.5 g/gCr. Patients were randomly assigned to a Topiroxostat or Febuxostat group, and the treatment target for the sUA level was < 6.0 mg/dl. The primary outcome was the change in the uPCR after 24 weeks. RESULTS: The change in the median uPCR after 24 weeks was not statistically significant after treatment in the Topiroxostat or Febuxostat group (0.05 g/gCr and - 0.04 g/gCr, respectively). However, the sUA levels decreased significantly in both groups (Topiroxostat group: 8.6 ± 1.1 at baseline to 6.0 ± 1.1 mg/dl at 24 weeks, Febuxostat group: 8.4 ± 1.1 mg/dl at baseline to 5.9 ± 1.3 mg/dl at 24 weeks). No significant change in the eGFR after 24 weeks was noted in either the Topiroxostat or Febuxostat group (- 0.04 ± 4.59 ml/min/1.73 m2 and 0.31 ± 4.70 ml/min/1.73 m2, respectively). CONCLUSIONS: In this study, XO inhibitors did not significantly reduce the uPCR in chronic kidney disease stage 3 and 4 patients with hyperuricemia.

Applications of a novel biodetection system to saliva using protein fingerprints with data processing.

A fundamental method has been developed focusing on a facile and rapid examination of periodontal disease. Periodontal disease is an oral disease thought to affect 80% of adults, and early detection with treatment is desirable for the improvement of the quality of life. Unfortunately conventional methods are not consistent as the disease is caused by a number of undefined bacteria and detection relies on the skills of the dentist. Thus an objective detection system is required. We have performed an experiment on saliva using a novel biodetection system, designated PepTenChip®. A disease model for saliva was prepared using a specimen from a healthy subject and a mixture of hemoglobin (f-Hb) and lactate dehydrogenase (LDH), which is used as a periodontal disease marker protein with healthy saliva. PepTenChip® is a peptide microarray in which fluorescent labelled structured peptides are immobilized on a novel amorphous carbon substrate. Since the peptides used as capture molecules are fluorescently labelled, labeling of analytes is not necessary. The fluorescence intensity change before and after application of analytes are detected rather than the ON/OFF detection common to conventional microarrays using a set of antigen-antibody. The fluorescence intensity value changes according to the concentration of captured protein allowing the generation of protein fingerprint (PFP) and dendrograms. The present method does not rely on a "one to one" interaction, unlike conventional biodetection, and advantages can be envisaged in the case of an undefined or unknown cause of disease. The statistical analyses, such as multivariate analyses, allow classification of the type of proteins added in saliva as mimetics of disease. PepTenChip® system is useful and convenient for examination of periodontal disease in health care.

Hydrogen-Rich Water Intake Accelerates Oral Palatal Wound Healing via Activation of the Nrf2/Antioxidant Defense Pathways in a Rat Model.

The wound healing process attempts to restore the integrity and function of the injured tissue. Additionally, proinflammatory cytokines, growth factors, and oxidative stress play important roles in wound healing. The aim of this study was to determine whether hydrogen-rich water intake induces the activation of the Nrf2/antioxidant defense pathway in rat palatal tissue, thereby reducing systemic oxidative stress and proinflammatory cytokine levels and promoting healing-associated genes. A circular excisional wound was created in the oral palatal region, and the wound healing process was observed. The rats were divided into two experimental groups in which either hydrogen-rich water or distilled water was consumed. In the drinking hydrogen-rich water, the palatal wound healing process was accelerated compared to that in the control group. As molecular hydrogen upregulated the Nrf2 pathway, systemic oxidative stresses were decreased by the activation of antioxidant activity. Furthermore, hydrogen-rich water intake reduced proinflammatory cytokine levels and promoted the expression of healing-associated factors in rat palatal tissue. In conclusion, hydrogen-rich water intake exhibited multiple beneficial effects through activation of the Nrf2/antioxidant defense pathway. The results of this study support the hypothesis that oral administration of hydrogen-rich water benefits the wound healing process by decreasing oxidative stress and inflammatory responses.

Correlation Between Arteriosclerosis and Periodontal Condition Assessed by Lactoferrin and α1-Antitrypsin Levels in Gingival Crevicular Fluid.

Patients with periodontal disease exhibit exacerbated atherosclerosis, aortic stiffness, or vascular endothelial dysfunction. However, in a recent scientific statement, the American Heart Association noted that neither has periodontal disease been proven to cause atherosclerotic vascular disease nor has the treatment of periodontal disease been proven to prevent atherosclerotic vascular disease. Therefore, the aim of the present study was to examine the correlation between periodontal condition and arteriosclerosis in patients with coronary artery disease (CAD), which is usually accompanied by systemic arteriosclerosis.We measured levels of gingival crevicular fluid lactoferrin (GCF-Lf) and α1-antitrypsin (GCF-AT) in 72 patients (67 ± 8 years, 56 men) with CAD. Furthermore, we evaluated the maximum intima-media thickness (max IMT) and plaque score of the carotid arteries as well as brachial-ankle pulse wave velocity (baPWV) and flow-mediated dilation (FMD) of the brachial artery, each of which is a parameter for determining arteriosclerosis status. The average level of GCF-Lf was 0.29 ± 0.36 µg/mL and that of GCF-AT was 0.31 ± 0.66 µg/mL, with significant correlation between the two (r = 0.701, P < 0.001). No significant difference in GCF-Lf and GCF-AT levels was observed between patients with single-, double-, and triple-vessel CAD. There were no significant correlations between the arteriosclerosis parameters (ie, max IMT, plaque score, baPWV, and FMD) and GCF-Lf or GCF-AT.No correlation between the GCF biomarkers and the severity of arteriosclerosis was detected. This result may suggest that worsening of the periodontal condition assessed by GCF biomarkers is not a major potential risk factor for arteriosclerosis.

Relationship among salivary antioxidant activity, cytokines, and periodontitis: the Nagasaki Island study.

AIM: Antioxidant activities and cytokine levels in human body fluids are considered to be strongly associated with periodontitis. The aim of this study was to elucidate the relationship between salivary antioxidant activities against superoxide or hydroxyl radical, cytokines, and periodontal conditions through a community-based cross-sectional study conducted in Goto city, Japan. MATERIALS AND METHODS: Saliva samples were analysed for superoxide or hydroxyl radical scavenging activities and cytokine levels from 160 participants. We demonstrated that saliva contained superoxide and hydroxyl radical scavenging activities by using electron spin resonance with a spin-trapping agent. The concentrations of eight cytokines were measured using multiplex bead assays. RESULTS: There were significant differences in salivary superoxide or hydroxyl radical scavenging activity, and the levels of Interleukin-1ß, Interleukin-6, and Interleukin-8 between periodontitis classifications. Multivariate stepwise logistic regression model showed that salivary superoxide and hydroxyl radical scavenging activities were significantly associated with the classification of periodontitis. In addition, salivary superoxide scavenging activity was found to have significant association with all periodontal parameters using multiple linear regression analysis. CONCLUSIONS: These findings suggest that the evaluation of salivary antioxidant activities, as assessed by electron spin resonance, are associated with periodontitis and various clinical variables in community-dwelling participants (ClinicalTrials.gov number NCT01742728).

Biological impacts of resveratrol, quercetin, and N-acetylcysteine on oxidative stress in human gingival fibroblasts.

In periodontitis, production of reactive oxygen species (ROS) by neutrophils induces oxidative stress and deteriorates surrounding tissues. Antioxidants reduce damage caused by ROS and are used to treat diseases involving oxidative stress. This study summarizes the different effects of resveratrol, quercetin, and N-acetylcysteine (NAC) on human gingival fibroblasts (HGFs) under oxidative stress induced by hydrogen peroxide. Real-time cytotoxicity analyses reveals that resveratrol and quercetin enhanced cell proliferation even under oxidative stress. Of the antioxidants tested, resveratrol is the most effective at inhibiting ROS production. HGFs incubated with resveratrol and quercetin up-regulate the transcription of type I collagen gene after 3 h, but only resveratrol sustained this up-regulation for 24 h. A measurement of the oxygen consumption rate (OCR, mitochondrial respiration) shows that resveratrol generates the highest maximal respiratory capacity, followed by quercetin and NAC. Simultaneous measurement of OCR and the extracellular acidification rate (non-mitochondrial respiration) reveals that resveratrol and quercetin induce an increase in mitochondrial respiration when compared with untreated cells. NAC treatment consumes less oxygen and enhances more non-mitochondrial respiration. In conclusion, resveratrol is the most effective antioxidant in terms of real-time cytotoxicity analysis, reduction of ROS production, and enhancement of type I collagen synthesis and mitochondrial respiration in HGFs.

Resveratrol improves oxidative stress and prevents the progression of periodontitis via the activation of the Sirt1/AMPK and the Nrf2/antioxidant defense pathways in a rat periodontitis model.

Oxidative stress is a key factor regulating the systemic pathophysiological effects associated with periodontitis. Resveratrol is a phytochemical with antioxidant and anti-inflammatory properties that can reduce oxidative stress and inflammation. We hypothesized that resveratrol may prevent the progression of periodontitis and reduce systemic oxidative stress through the activation of the sirtuin 1 (Sirt1)/AMP-activated protein kinase (AMPK) and the nuclear factor E2-related factor 2 (Nrf2)/antioxidant defense pathways. Three groups of male Wistar rats (periodontitis treated with melinjo resveratrol, periodontitis without resveratrol, and control rats with no periodontitis or resveratrol treatment) were examined. A ligature was placed around the maxillary molars for 3 weeks to induce periodontitis, and the rats were then given drinking water with or without melinjo resveratrol. In rats with periodontitis, ligature placement induced alveolar bone resorption, quantified using three-dimensional images taken by micro-CT, and increased proinflammatory cytokine levels in gingival tissue. Melinjo resveratrol intake relieved alveolar bone resorption and activated the Sirt1/AMPK and the Nrf2/antioxidant defense pathways in inflamed gingival tissues. Further, melinjo resveratrol improved the systemic levels of 8-hydroxydeoxyguanosine, dityrosine, nitric oxide metabolism, nitrotyrosine, and proinflammatory cytokines. We conclude that oral administration of melinjo resveratrol may prevent the progression of ligature-induced periodontitis and improve systemic oxidative and nitrosative stress.

Association of gingival recession and other factors with the presence of dentin hypersensitivity.

Dentin hypersensitivity (DH) may be present in association with gingival recession. The aim of this study was to determine quantitatively the association of gingival recession and other factors with the presence of DH. One hundred and four Japanese subjects with or without gingival recession were randomly selected. Intact canines and/or first premolars in both maxillary and mandibular quadrants were analyzed. Gingival recession was measured as a vertical length at the buccal site of the teeth. DH was recorded as an ordered categorical variable registering four increasing levels of pain after cold stimulation; from no discomfort to severe pain during and after stimulation (DH1, 2, 3, and 4). Association of DH with periodontal parameters and daily lifestyle was also investigated. Tooth-based analysis of 446 teeth from 104 subjects revealed that DH level was significantly higher in recessive teeth (1, 2, 3, and 4-8 mm) than in non-recessive teeth (0 mm). DH-positive rate in non-recessive teeth was only 18 % (DH1; 14 %, DH2; 3 %, and DH3; 1 %). Highest DH level was observed in teeth with severe recession (4-8 mm), showing DH0; 21 %, DH1; 33 %, DH2; 31 %, and DH3; 15 %. Recession-dependent increase in DH was observed, showing 18, 49, 52, 60, and 79 % DH-positive in teeth with 0, 1, 2, 3, and 4-8 mm recession, respectively. Plaque-free teeth showed a higher DH level than plaque-stained teeth, suggesting that good plaque control may be associated with the presence of DH. There were no significant differences in DH of teeth on the basis of smoking, probing depth, and bleeding on probing. Multiple logistic regression analysis revealed that gingival recession [odds ratio (OR) = 10.2, 95 % confidence interval (CI) = 5.5-18.9] and plaque deposition (OR = 0.3, 95 % CI = 0.2-0.5) were significant contributors to DH. Multilevel modeling analysis revealed that not only gingival recession and plaque deposition but also V-shaped cervical notch and tooth brushing frequency were associated with DH. These results demonstrate that the progression of gingival recession, plaque-free teeth, V-shaped cervical notch, and frequent brushing may be significant predictors of DH in canines and first premolars.

Study on the subgel-phase formation using an asymmetric phospholipid bilayer membrane by high-pressure fluorometry.

The myristoylpalmitoylphosphatidylcholine (MPPC) bilayer membrane shows a complicated temperature-pressure phase diagram. The large portion of the lamellar gel (L(ß)'), ripple gel (P(ß)'), and pressure-induced gel (L(ß)I) phases exist as metastable phases due to the extremely stable subgel (L(c)) phase. The stable L(c) phase enables us to examine the properties of the L(c) phase. The phases of the MPPC bilayers under atmospheric and high pressures were studied by small-angle neutron scattering (SANS) and fluorescence spectroscopy using a polarity-sensitive fluorescent probe Prodan. The SANS measurements clearly demonstrated the existence of the metastable L(ß)I phase with the smallest lamellar repeat distance. From a second-derivative analysis of the fluorescence data, the line shape for the L(c) phase under high pressure was characterized by a broad peak with a minimum of ca. 460 nm. The line shapes and the minimum intensity wavelength (λ″(min)) values changed with pressure, indicating that the L(c) phase has highly pressure-sensible structure. The λ″(min) values of the L(c) phase spectra were split into ca. 430 and 500 nm in the L(ß)I phase region, which corresponds to the formation of a interdigitated subgel L(c) (L(c)I) phase. Moreover, the phase transitions related to the L(c) phase were reversible transitions under high pressure. Taking into account the fluorescence behavior of Prodan for the L(c) phase, we concluded that the structure of the L(c) phase is highly probably a staggered structure, which can transform into the L(c)I phase easily.

Mucosal immune features to phosphorylcholine by nasal Flt3 ligand cDNA-based vaccination.

Phosphorylcholine (PC) is an immunodominant epitope in some pathogens including Streptococcus pneumoniae and it is well-known that PC-specific antibodies (Abs) play a key role in the induction of protective immunity against pneumococcal infection. In this study, we examined whether nasal administration of DNA plasmid encoding Flt3 ligand gene (pFL) as a mucosal adjuvant plus PC-conjugated keyhole limpet hemocyanin (PC-KLH), would elicit PC-specific immune responses, and characterized mucosal immune responses to PC induced by this nasal vaccination. Nasal immunization with pFL plus PC-KLH enhanced induction of PC-specific IgA and IgM Abs in airway secretions when compared with mice given PC-KLH with or without empty plasmid gene (pORF) as controls; in addition to the mucosal immune responses, PC-specific immune responses in serum were also induced. Furthermore, the mucosal and serum IgA and IgM Abs in mice given pFL plus PC-KLH nasally, exhibited high-specificity for the PC molecule. Of interest, the PC-specific Abs bound dose-dependently to anti-T15 idiotype (AB1-2). Thus, the inhibition of S. pneumoniae colonization on the nasal cavity and lungs after nasal challenge with the live organism was significantly elicited in mice immunized with pFL plus PC-KLH compared to that of mice immunized with antigen with pORF. Taken together, these findings show that nasal administration of pFL with PC-KLH elicited T15-like anti-PC IgA and IgM Abs in the respiratory tracts, and further attenuated S. pneumoniae colonization on the respiratory tracts. Nasal administration of Flt3 ligand cDNA with PC may contribute to the development of nasal vaccination for prevention of S. pneumoniae infection.

The nasal dendritic cell-targeting Flt3 ligand as a safe adjuvant elicits effective protection against fatal pneumococcal pneumonia.

We have previously shown that a pneumococcal surface protein A (PspA)-based vaccine containing DNA plasmid encoding the Flt3 ligand (FL) gene (pFL) as a nasal adjuvant prevented nasal carriage of Streptococcus pneumoniae. In this study, we further investigated the safety and efficacy of this nasal vaccine for the induction of PspA-specific antibody (Ab) responses against lung infection with S. pneumoniae. C57BL/6 mice were nasally immunized with recombinant PspA/Rx1 (rPspA) plus pFL three times at weekly intervals. When dynamic translocation of pFL was initially examined, nasal pFL was taken up by nasal dendritic cells (DCs) and epithelial cells (nECs) but not in the central nervous systems, including olfactory nerve and epithelium. Of importance, nasal pFL induced FL protein synthesis with minimum levels of inflammatory cytokines in the nasal washes (NWs) and bronchoalveolar lavage fluid (BALF). NWs and BALF as well as plasma of mice given nasal rPspA plus pFL contained increased levels of rPspA-specific secretory IgA and IgG Ab responses that were correlated with elevated numbers of CD8(+) and CD11b(+) DCs and interleukin 2 (IL-2)- and IL-4-producing CD4(+) T cells in the nasal mucosa-associated lymphoid tissues (NALT) and cervical lymph nodes (CLNs). The in vivo protection by rPspA-specific Abs was evident in markedly reduced numbers of CFU in the lungs, airway secretions, and blood when mice were nasally challenged with Streptococcus pneumoniae WU2. Our findings show that nasal pFL is a safe and effective mucosal adjuvant for the enhancement of bacterial antigen (Ag) (rPspA)-specific protective immunity through DC-induced Th2-type and IL-2 cytokine responses.

Levels of salivary stress markers in patients with anxiety about halitosis.

OBJECTIVE: To investigate the relationship between salivary stress markers and mental stress states in patients complaining of oral malodour. The utility of the salivary stress markers in assessment of mental conditions of those patients was also investigated. DESIGN: The study population included 74 patients, aged 20-59 years, who complained of oral malodour and were referred to the Breath Odor Clinic at Tokushima University Hospital. Patients were classified into two groups, genuine halitosis (GH) and psychosomatic halitosis (PH), according to the results of organoleptic rating measurement. All patients were subjected to examination by the Cornell Medical Index (CMI) Health Questionnaire. Resting saliva was collected and levels of salivary IgA, cortisol and chromogranin A were determined by ELISA. Twenty-three volunteers not complaining of halitosis were included as the control group. Kruskal-Wallis test and Mann-Whitney's U-test were used for statistical analysis. RESULTS: A significant increase was observed in the concentrations of salivary cortisol in the PH group as compared with GH and control groups (p<0.05). Concentrations of IgA and chromogranin A in saliva were not significantly different among the three groups. In addition, higher salivary cortisol concentrations were found in CMI scale III and IV (tendency towards neurosis) than in scale I and II (normal) (p<0.05). Since salivary cortisol reflects a status of chronic stress condition, psychosomatic halitosis might be closely related to this state of chronic stress. CONCLUSIONS: Determination of cortisol levels in saliva may provide useful information for evaluating the mental status of patients complaining of halitosis.

Fusobacterium nucleatum envelope protein FomA is immunogenic and binds to the salivary statherin-derived peptide.

We have previously shown that one of the minimal active regions of statherin, a human salivary protein, for binding to Fusobacterium nucleatum is a YQPVPE amino acid sequence. In this study, we identified the FomA protein of F. nucleatum, which is responsible for binding to the statherin-derived YQPVPE peptide. Overlay analysis showed that a 40-kDa protein of the F. nucleatum cell envelope (40-kDa CE) specifically bound to the YQPVPE peptide. The equilibrium association constant between the affinity-purified 40-kDa CE and the YQPVPE peptide was 4.30 x 10(6). Further, the purity and amino acid sequence analyses of the purified 40-kDa CE revealed approximately 98.7% (wt/wt) purity and a high degree of homology with FomA, a major porin protein of F. nucleatum. Thus, a FomA-deficient mutant failed to bind to the YQPVPE peptide. In addition, increased levels of a FomA-specific mucosal IgA antibody (Ab) and plasma IgG and IgA Abs were seen only in mice immunized nasally with cholera toxin (CT) and the purified 40-kDa FomA protein. Interestingly, saliva from mice that received FomA plus CT as a mucosal adjuvant nasally prevented in vitro binding of F. nucleatum to statherin-coated polyvinyl chloride plates. Taken together, these results suggest that induction of specific immunity to the 40-kDa FomA protein of F. nucleatum, which specifically binds to the statherin-derived peptide, may be an effective tool for preventing the formation of F. nucleatum biofilms in the oral cavity.

Intranasal immunization with phosphorylcholine induces antigen specific mucosal and systemic immune responses in mice.

Phosphorylcholine (PC) is a structural component of a wide variety of pathogens including Streptococcus pneumoniae and Haemophilus influenzae, and anti-PC immune responses are known to protect mice against invasive bacterial diseases. The present study tested the capability of PC as an intranasal plurispecific vaccine against upper airway infections. BALB/c mice immunized with intranasal PC-keyhole limpet hemocyanin (KLH) plus cholera toxin (CT) as a mucosal adjuvant showed increased PC-specific IgM in serum, IgA in nasal wash and saliva, and numbers of PC-specific nasal and splenic antibody producing cells. Enhanced production of IL-4 and IFN-gamma by CD4+ T cells indicated the participation of Th2- and Th1-type cells. Salivary IgA antibodies produced by intranasal immunization with PC-KLH plus CT reacted to most strains of S. pneumoniae and H. influenzae. Further we demonstrated that the clearance of S. pneumoniae and H. influenzae from the nasal tract was significantly enhanced by nasal immunization with PC-KLH and CT. Thus, intranasal vaccination to induce PC-specific immune responses might help to prevent upper airway infections caused by S. pneumoniae and H. influenzae.

Development of a Japanese version of the Oral Impacts on Daily Performance (OIDP) scale: a pilot study.

The Oral Impacts on Daily Performance (OIDP) is a well-known oral health-related QOL instrument used internationally. The aim of this study was to develop and test a Japanese version of the OIDP for use in interviews. Following an internationally established method, the OIDP scale was translated using standardized methodology that consisted of forward translation, pilot study and backward translation. A pilot study was carried out using the revised version with 47 local residents (range, 40-105 years). In the item analysis of this study, there were no missing values or ambiguous responses. Twenty-eight percent of the participants replied that they 'had discomfort caused by an oral health problem' in the 'eating' items. Cronbach's alpha coefficient was 0.77, indicating the internal consistency reliability of the questionnaire. Denture wearers had significantly higher OIDP scores in covariance analysis with age and sex as adjustment factors (P < 0.05). Based on the results, the questionnaire was re-evaluated. A back translation was produced and approved by the original author. Further assessment and validation of this scale is needed in a study with larger sample size.

Infective endocarditis and dental procedures: evidence, pathogenesis, and prevention.

Infective endocarditis is a serious infection occurring on the endothelial surfaces of the heart, especially at the valves. Oral commensal bacteria are the important etiologic agents in this disease. Common dental procedures, even non-surgical dental procedures, can often cause bacteremia of oral commensals. Periodontally diseased patients are at risk from bacteremia even after brushing the teeth. Bacteremia itself rarely affect healthy people but they can result in mortal infective endocarditis in those who have a predisposed risk for this disease, such as those with heart valve diseases, pacemaker implantation, etc. Infective endocarditis is thus established when all the 3 conditions are present simultaneously, i. e., 1) a predisposing impairments in the heart, 2) the introduction of bacteria into the bloodstream, and 3) the virulence of bacteria. Antibiotics have to be adequately used to prevent this infection, however, their frequent uses generates drug-resistant mutant bacteria, which is a serious social problem. The development of novel alternative drugs to be used instead of the current antibiotics is thus highly desired. We are now using several types of combinatorial peptide libraries to search for small size molecular mimetics that can interfere with the adhesion of bacteria to the target organ. The use of such peptides is expected to lead to the development of compounds for a novel preventive drug which does not kill bacteria, thus making it safer and less likely to generate drug-resistant mutants.

Experimental infective endocarditis induced by human supragingival dental plaque in rats.

Human dental plaque is thought to contribute to disease, not only in the oral cavity but also at other body sites. To investigate the pathogenicity of dental plaque in tissues remote from the mouth, we examined the ability of human supragingival dental plaque to induce infective endocarditis (IE) in rats. In total, 15 out of 27 catheterized rats survived after intravenous injections with human supragingival dental plaque suspensions containing 3 x 10(6) colony-forming units (CFU) of bacterial cells. In surviving rats, infected vegetations were formed in all except one rat. The microbial composition of the infected vegetations was different from that of the respective dental plaque inocula, with Streptococcus oralis comprising the majority of the isolates. In rats affected with endocarditis, the aortic sinus was filled with fibrinous vegetation containing bacteria. Inflammatory cells infiltrated the aortic valve, the aorta adjacent to the valve, and the cardiac muscles. The inoculation of catheterized rats with a cell suspension of S. oralis isolate (5 x 10(6) CFU) was not lethal but capable of inducing endocarditis in all animals. The results suggest that if dental plaque were introduced into the bloodstream, it could serve as a potent source of bacteria causing IE in humans.