Publications
-
Article: Hypoplasia in crown of primary mandibular left lateral incisor identified in infant Japanese girl
[Show abstract] [Hide abstract]
ABSTRACT: A girl aged 0 years 11 months was referred to our clinic by a local pediatrician for examination of a missing tooth crown of a primary mandibular left lateral incisor. Our intraoral examination showed that seven primary incisors had emerged into the oral cavity, while no tooth crown was noted in the region of the primary mandibular left lateral incisor. A calcified structure was identified close to the gingival margin, which had a bone-like appearance and color, with no inflammation seen in the gingiva around the structure. Furthermore, the pulp space could be seen through the layer of hard tissue located close to the gingival region. A periapical radiograph taken at the first visit demonstrated a root-like structure with dentin and pulp, whereas enamel was not detected. The structure was speculated to be the root of the primary mandibular left lateral incisor, which was in the developmental stage. As there were no abnormal signs or symptoms, we decided to perform periodical examinations at 3-month intervals. Periapical radiographs taken at 1Y0M and 1Y7M showed root formation with no unusual conditions observed around the affected tooth.Pediatric Dental Journal. 01/2014; - [Show abstract] [Hide abstract]
ABSTRACT: We previously reported a quite uncommon case of delayed eruption of primary mandibular bilateral incisors with severe lingual inclination identified in a Japanese girl aged 2 years 8 months. An intraoral examination demonstrated the tooth crown morphology of the primary mandibular incisors in the lingual submucosal area, while radiographic examinations of the affected teeth revealed what appeared to be a standard root morphology and the permanent successors located close to the affected teeth. We decided to perform periodical examinations at least until the roots of the permanent successors were sufficiently formed and here report recent findings in this case. At 2Y10M, the edge of the tooth crown of the primary mandibular left central incisor had emerged into the oral cavity and one-third of the tooth crown was identified at 2Y11M. Thereafter, the tooth crown of the primary mandibular right central incisor was identified under the mucosa at 3Y1M. A periapical radiograph taken at 3Y7M demonstrated formation of the permanent successors under development. At 3Y10M, nearly the entire part of the tooth crowns of both affected teeth had emerged and then they started to move gradually in a labial direction. At 4Y2M, the crowns of the affected were nearly within the dental arch, while periapical radiograph images showed straight roots for the affected teeth and the developing permanent successors. We intend to continue to perform periodical examinations to follow the development of the permanent successors until eruption.Pediatric Dental Journal. 01/2014; - [Show abstract] [Hide abstract]
ABSTRACT: Streptococcus mutans, an aetiologic agent of dental caries, is a pathogen for infective endocarditis (IE). We investigated strains that express collagen-binding proteins (CBPs) with further classification based on expression of the 190-kDa protein antigen (PA). Zeta-potential values of strains TW871 (CBP+/PA+) and MT8148 (CBP-/PA+), and their respective PA-defective mutant strains TW871PD (CBP+/PA-) and MT8148PD (CBP-/PA-), were analysed, as were their adhesion to and invasion of human umbilical vein endothelial cells (HUVECs). The distribution of strains from the oral cavities of 200 healthy individuals was analysed for CBP and/or PA expression and the strains were characterised for their adhesion and invasion properties. TW871PD and MT8148PD showed significantly lower zeta-potential values than TW871 and MT8148, respectively. Collagen-binding rates were significantly higher for TW871PD than for TW871 but nearly negligible for MT8148 and MT8148PD. The adhesion and invasion rates of HUVECs were significantly higher for TW871PD than for TW871 and significantly higher for TW871 than for MT8148 and MT8148PD. The prevalence of CBP+ strains was ∼10% and ∼3% in the case of CBP+/PA- strains. Analyses of 200 clinical strains showed the CBP+/PA- group to have higher adhesion and invasion rates than other groups. CBP+/PA- S. mutans strains, despite their low distribution frequency, may be highly virulent for infective endocarditis.Archives of oral biology 11/2013; 58(11):1627-1634. · 1.65 Impact Factor - [Show abstract] [Hide abstract]
ABSTRACT: Objective Streptococcus mutans, a major dental caries pathogen, has shown to be associated with the aggravation of cerebral hemorrhage and inflammatory bowel diseases. In this study, we evaluated the effects of S. mutans on the development of non-alcoholic steatohepatitis (NASH) in a mouse model. Materials and methodsStreptococcus mutans oral strain MT8148 (serotype c) and a blood isolate TW871 (k) were used. C57BL/6J mice (6 weeks old) were fed a high-fat diet for 4 weeks; the test strains or phosphate-buffered saline was then intravenously administered. Mice were euthanized after 8 or 12 weeks. Whole body, extirpated liver, and visceral fat weights were determined, and histopathological evaluations of the liver specimens were performed. ResultsMice infected with TW871 showed significantly greater body and liver weights than those administered MT8148 or phosphate-buffered saline. Histopathological analyses revealed prominent infiltration of inflammatory cells and adipocellular deposition in livers extirpated 8 weeks after an infection with TW871; fibrosis was also observed in livers extirpated after 12 weeks. Conclusion These results suggest that a specific strain of S. mutans could induce NASH.Oral Diseases 10/2013; · 2.38 Impact Factor - [Show abstract] [Hide abstract]
ABSTRACT: Infective endocarditis (IE) is known to be a life-threatening disease and prevention of its onset is important. Oral amoxicillin (AMPC) is generally prescribed to patients at risk for IE prior to undergoing risky procedures, such as invasive dental treatments. We previously found that approximately 5% of systemically healthy Japanese subjects harbor strains highly resistant to AMPC. In the present study, the prevalence of strains in patients at risk for IE was investigated. Thirty-four Japanese children and adolescents designated at risk for IE by their cardiovascular surgeons participated. Dental plaque specimens were obtained at recall examinations for dental checkups and placed in sterile phosphate-buffered saline, then diluted and streaked onto selective media for oral streptococci and also media containing AMPC. Nine strains with a minimum inhibitory concentration of AMPC of 16μg/mL or more were isolated from 7 of the subjects (20.6%), each of which was also resistant to other antibiotics analyzed except for new quinolone drugs. The 16S rRNA sequence of each strain demonstrated that all were oral streptococcal species. In addition, dental plaque specimens collected from 5 subjects after an additional interval of 3-4 months showed that 2 harbored the same clones at different time points. These findings suggest a higher prevalence of AMPC-resistant strains in children and adolescents at risk for IE as compared to systemically healthy subjects. Thus, alternative antibiotics should be considered for such subjects when performing prophylaxis procedures.Journal of Cardiology 06/2013; · 2.30 Impact Factor - [Show abstract] [Hide abstract]
ABSTRACT: We present results for three charmonia states (psi^prime, chi_c and J/psi) in d+Au collisions at |y|<0.35 and sqrt(s_NN)=200 GeV. We find that the modification of the psi^prime yield relative to that of the J/psi scales approximately with charged-particle multiplicity at midrapidity across p+A, d+Au, and A+A results from the Super Proton Synchrotron and the Relativistic Heavy Ion Collider. In large impact-parameter collisions we observe a similar suppression for the psi^prime and J/psi, while in small impact-parameter collisions the more weakly bound psi^prime is more strongly suppressed. Owing to the short time spent traversing the Au nucleus, the larger psi^prime suppression in central events is not explained by an increase of the nuclear absorption due to meson formation time effects.05/2013; - [Show abstract] [Hide abstract]
ABSTRACT: OBJECTIVES: Streptococcus mutans can aggravate colitis in mice. We evaluated the virulence of colitis using type strains as well as blood isolates of several oral streptococcal species. MATERIALS AND METHODS: We investigated the susceptibility of blood isolates of several oral streptococci to phagocytosis, adhesion to and invasion of hepatic cells and interferon-γ secretion. A mouse model of dextran sodium sulphate-induced colitis was used to evaluate bacterial aggravation of colitis. In addition, interferon-γ antibody was administered to mice with prominent aggravation of colitis. RESULTS: In vitro analyses showed that Streptococcus sanguinis ATCC 10556 was a possible virulent strain among type strains of several oral streptococci, and that analysis of blood isolates of S. sanguinis TW289 revealed a potential virulent strain. Intravenous administration of ATCC 10556 and TW289 caused prominent aggravation of dextran sodium sulphate-induced colitis, and histopathological examinations showed that interferon-γ secretion due to infection of hepatic cells caused colitis aggravation. Administration of interferon-γ antibody suppressed TW289-induced colitis. CONCLUSION: These results suggest that some virulent oral streptococcal strains are associated with the aggravation of colitis induced by enhanced secretion of interferon-γ when they invade the bloodstream.Oral Diseases 04/2013; · 2.38 Impact Factor - [Show abstract] [Hide abstract]
ABSTRACT: Impaction is defined as a condition in which a tooth fails to erupt within a normal range of functional position. The condition is generally found in permanent teeth, while impaction of primary teeth is considered to be uncommon. We previously presented a rare case of delayed development of a maxillary right second premolar with an inversely positioned corresponding primary molar identified in a girl aged 10 years and 4 months. In the present report of the same patient, we show transitional changes in location and developmental stage of the affected permanent tooth and impacted primary tooth noted during periodical examinations over a 5.5 year period. At 13 years and 2 months, the root of the permanent tooth began to develop, after which the root extended to half of the entire length at 15 years and 3 months. At the most recent examination conducted at 15 years and 9 months, the permanent successor had emerged into the oral cavity and the impacted primary molar maintained a similar position close to the inferior wall of the maxillary sinus without any symptoms. Throughout the observation period, the dental age of the maxillary right second premolar was calculated to be approximately 3 to 4 years behind those of the other second premolars. Our findings in the present case led us to consider that careful observation of the developmental stage of an unerupted permanent tooth is important, while no intervention is required before confirming tooth development as the patient grows, even if the dental age of the corresponding tooth is much later than the ages of other teeth.Pediatric Dental Journal. 04/2013; 23(1):62–65. - [Show abstract] [Hide abstract]
ABSTRACT: A girl aged 2 years and 8 months came to our clinic for consultation with regard to unerupted primary mandibular bilateral central incisors. An intraoral examination revealed that the teeth had not emerged into the oral cavity and showed a tooth crown morphology similar to that of the primary mandibular incisors, which appeared in the lingual submucosal area outside of the mandibular dental arch. Periapical radiographs demonstrated that the tooth crowns of both affected teeth were severely displaced to the lingual side. Computed tomography examinations were performed to clarify the three-dimensional positions of the affected teeth and their permanent successors, which revealed that the affected teeth were located in their estimated positions and had a standard root morphology. In addition, the permanent successors, which had not initiated root formation, were located close to the affected teeth. We decided to postpone extraction of the affected teeth and perform periodical examinations until the roots of the permanent successors are sufficiently formed. At the age of 2 years and 10 months, the edge of the tooth crown of the primary mandibular left central incisor was found emerged into the oral cavity. According to her parents, the patient did not complain of the emerging edge and no abnormal conditions were observed around the tooth.Pediatric Dental Journal. 04/2013; 23(1):66–69. - [Show abstract] [Hide abstract]
ABSTRACT: OBJECTIVE: Streptococcus mutans, an oral pathogen associated with infective endocarditis (IE), possesses two genes encoding collagen-binding proteins, namely cnm and cbm. In this study, we used multilocus sequence typing (MLST) of S. mutans with the cbm gene. DESIGN: Forty-five S. mutans strains including 15 strains with the cnm gene, 15 strains with the cbm gene, and 15 strains without these two genes were analysed by MLST. In addition, the collagen-binding properties as well as the abilities to adhere to and invade human umbilical vein endothelial cells (HUVEC) were also evaluated for all strains. RESULTS: In the groups of cnm-positive and cbm-positive strains, all properties, including collagen binding, adhesion, and invasion were significantly greater than those of the cnm-cbm-negative group. Moreover, MLST revealed three clonal complexes of S. mutans possessing the cbm gene. These three clones showed no close relatedness with clones of strains containing the cnm gene. Among three clones harbouring the cbm gene, two clones belong to serotype k, and appeared to be associated with the pathogenesis of IE due to their strong collagen binding and relatively enhanced abilities to adhere to and invade endothelial cells. However, such properties were relatively weak in the other non-serotype k clone possessing the cbm gene. CONCLUSIONS: MLST indicated a difference in evolution between S. mutans strains with the cbm gene and those with the cnm gene. In addition, this technique also suggested the importance of cbm-positive S. mutans clones relative to the pathogenesis of IE.Archives of oral biology 03/2013; · 1.65 Impact Factor - [Show abstract] [Hide abstract]
ABSTRACT: We analyzed the distribution of 11 periodontitis-related bacterial species in dental plaque collected from 176 Japanese dogs divided into young (less than 2 years of age), middle-aged (2-7 years of age) and elderly (more than 8 years of age) groups using a polymerase chain reaction method. Clinical examination revealed that no dogs in the young group were affected by periodontitis, whereas the rates for gingivitis and periodontitis were high in the middle-aged and elderly groups. In addition, the total numbers of bacterial species in the middle-aged and elderly groups were significantly greater than in the young group. Our findings suggest that age is an important factor associated with the distribution of periodontitis-related bacteria and periodontal conditions in dogs.Journal of Veterinary Medical Science 03/2013; · 0.88 Impact Factor - [Show abstract] [Hide abstract]
ABSTRACT: The PHENIX collaboration at the Relativistic Heavy Ion Collider (RHIC) reports measurements of azimuthal dihadron correlations near midrapidity in d+Au collisions at sqrt(s_NN)=200 GeV. These measurements complement recent analyses by experiments at the Large Hadron Collider (LHC) involving central p+Pb collisions at sqrt(s_NN)=5.02 TeV, which have indicated strong anisotropic long-range correlations in angular distributions of hadron pairs. The origin of these anisotropies is currently unknown. Various competing explanations include parton saturation and hydrodynamic flow. We observe qualitatively similar anisotropies at RHIC to those seen at the LHC, and when both are divided by an estimate of the initial-state eccentricity, the anisotropies follow a common multiplicity scaling. This scaling is also found to extend to heavy ion data at RHIC and the LHC, where the anisotropies are widely thought to be due to hydrodynamic flow. The results presented here, at much lower collision energy and with a deuteron projectile (instead of a proton), provide important new information for understanding the origin of these new long-range correlations.Physical Review Letters 03/2013; 111(21). · 7.94 Impact Factor -
Dataset: OMI PgII
-
Dataset: Heterogenic virulence
-
Article: Porphyromonas gingivalis fimbriae.
[Show abstract] [Hide abstract]
ABSTRACT: Marginal periodontitis is not a homogeneous disease but is rather influenced by an intricate set of host susceptibility differences as well as diversities in virulence among the harbored organisms. It is likely that clonal heterogeneity of subpopulations with both high and low levels of pathogenicity exists among organisms harbored by individuals with negligible, slight, or even severe periodontal destruction. Therefore, specific virulent clones of periodontal pathogens may cause advanced and/or aggressive periodontitis. Porphyromonas gingivalis is a predominant periodontal pathogen that expresses a number of potential virulence factors involved in the pathogenesis of periodontitis, and accumulated evidence shows that its expression of heterogenic virulence properties is dependent on clonal diversity. Fimbriae are considered to be critical factors that mediate bacterial interactions with and invasion of host tissues, with P. gingivalis shown to express two distinct fimbria-molecules, long and short fimbriae, on the cell surface, both of which seem to be involved in development of periodontitis. Long fimbriae are classified into six types (I to V and Ib) based on the diversity of fimA genes encoding FimA (a subunit of long fimbriae). Studies of clones with type II fimA have revealed their significantly greater adhesive and invasive capabilities as compared to other fimA type clones. Long and short fimbriae induce various cytokine expressions such as IL-1α, IL-β, IL-6, and TNF-α, which result in alveolar bone resorption. Although the clonal diversity of short fimbriae is unclear, distinct short fimbria-molecules have been found in different strains. These fimbriae variations likely influence the development of periodontal disease.Journal of Oral Microbiology 01/2013; 5. -
Article: Potential involvement of collagen‐binding proteins of Streptococcus mutans in infective endocarditis
[Show abstract] [Hide abstract]
ABSTRACT: Objective Streptococcus mutans, a major pathogen of dental caries, is considered to be one of the causative agents of infective endocarditis (IE). Two types of cell surface collagen‐binding proteins, Cnm and Cbm, have been identified in the organism. The aim of the present study was to analyze these proteins as possible etiologic factors for IE. Materials and Methods The binding activities of S. mutans strains to collagen types I, III, and IV were analyzed relative to the presence of Cnm and Cbm, as were their adhesion and invasion properties with human umbilical vein endothelial cells (HUVEC). In addition, distributions of the genes encoding Cnm and Cbm in S. mutans‐positive heart valve specimens extirpated from IE and non‐IE patients were analyzed by PCR. ResultsMost of the Cbm‐positive strains showed higher levels of binding to type I collagen as well as higher rates of adhesion and invasion with HUVEC as compared to the Cnm‐positive strains. Furthermore, the gene encoding Cbm was detected significantly more frequently in heart valve specimens from IE patients than from non‐IE patients. Conclusions These results suggest that the collagen‐binding protein Cbm of S. mutans may be one of the potential important factor associated with the pathogenesis of IE.Oral Diseases 01/2013; 19(4). · 2.38 Impact Factor -
Article: Double-spin asymmetry of electrons from heavy-flavor decays in p plus p collisions at root s=200 GeV
[Show abstract] [Hide abstract]
ABSTRACT: We report on the first measurement of the double-spin asymmetry, A(LL), of electrons from the decays of hadrons containing heavy flavor in longitudinally polarized p + p collisions at root s = 200 GeV for p(T) = 0.5 to 3.0 GeV/c. The asymmetry was measured at midrapidity (vertical bar eta vertical bar < 0.35) with the PHENIX detector at the Relativistic Heavy Ion Collider. The measured asymmetries are consistent with zero within the statistical errors. We obtained a constraint for the polarized gluon distribution in the proton of vertical bar Delta g/g(log(10)(x) = -1.6(-0.4)(+0.5), mu = m(T)(c)vertical bar(2) < 0.030 (1 sigma) based on a leading-order perturbative quantum chromodynamics model, using the measured asymmetry. DOI: 10.1103/PhysRevD.87.012011Physical Review D 01/2013; 87(1). · 4.69 Impact Factor -
Article: Cold-Nuclear-Matter Effects on Heavy-Quark Production in d+Au Collisions at sqrt[s_{NN}]=200 GeV.
[Show abstract] [Hide abstract]
ABSTRACT: The PHENIX experiment has measured electrons and positrons at midrapidity from the decays of hadrons containing charm and bottom quarks produced in d+Au and p+p collisions at sqrt[s_{NN}]=200 GeV in the transverse-momentum range 0.85≤p_{T}^{e}≤8.5 GeV/c. In central d+Au collisions, the nuclear modification factor R_{dA} at 1.5<p_{T}<5 GeV/c displays evidence of enhancement of these electrons, relative to those produced in p+p collisions, and shows that the mass-dependent Cronin enhancement observed at the Relativistic Heavy Ion Collider extends to the heavy D meson family. A comparison with the neutral-pion data suggests that the difference in cold-nuclear-matter effects on light- and heavy-flavor mesons could contribute to the observed differences between the π^{0} and heavy-flavor-electron nuclear modification factors R_{AA}.Physical Review Letters 12/2012; 109(24):242301. · 7.94 Impact Factor - [Show abstract] [Hide abstract]
ABSTRACT: The jet fragmentation function is measured with direct photon-hadron correlations in p+p and Au+Au collisions at sqrt(s_NN)=200 GeV. The p_T of the photon is an excellent approximation to the initial p_T of the jet and the ratio z_T=p_T^h/p_T^\gamma is used as a proxy for the jet fragmentation function. A statistical subtraction is used to extract the direct photon-hadron yields in Au+Au collisions while a photon isolation cut is applied in p+p. I_ AA, the ratio of jet fragment yield in Au+Au to that in p+p, indicates modification of the jet fragmentation function. Suppression, most likely due to energy loss in the medium, is seen at high z_T. The fragment yield at low z_T is enhanced at large angles. Such a trend is expected from redistribution of the lost energy into increased production of low-momentum particles.Physical Review Letters 12/2012; 111(3). · 7.94 Impact Factor - [Show abstract] [Hide abstract]
ABSTRACT: Genetically modified (GM) pigs are useful tools for many types of biomedical research. The objective of this study was to develop a reliable protocol for the reproduction of GM pigs using frozen epididymal sperm. Epididymal sperm were collected from 3 GM boars: (1) humanized Kusabira-Orange (huKO) transgenic, (2) mutant human hepatocyte nuclear factor 1α (HNF-1α) transgenic, and (3) α1,3-galactosyltransferase gene knockout (GalT-KO). Additionally, a wild type (WT) boar was also used for sperm collection. After collection, the sperm were frozen in Niwa and Sasaki freezing medium (Niwa et al. 1989 Manual for Cryopreservation of Pig Spermatozoa 19-23; 1.0×10(9)spermmL(-1)) using 0.5-mL straws. The sperm were cooled utilising the 2-step method, from 25 to 15°C at a rate of 0.17°Cmin(-1), and then from 15 to 5°C at 0.08°Cmin(-1). After cooling to 5°C, the straws were frozen in liquid nitrogen with 3% glycerol for storage. After storage for 0.5 to 21 months, the straws were thawed by immersion into a 37°C water bath. The recovered sperm were washed by centrifugation in PBS+1mgmL(-1) BSA and were resuspended in either Beltsville thawing solution (Pursel and Johnson. 1975 J. Anim. Sci. 40, 99-102) for intra-fallopian AI or in porcine fertilization medium (PFM, Research Institute for the Functional Peptides, Yamagata, Japan) for IVF. Prepubertal gilts (6.5 months), in which oestrus was induced by 1000IU eCG and 1500IU hCG given 66 or 72h apart, were surgically inseminated with 0.9-7.9×10(6) progressive motile sperm 41 to 51h after receiving an hCG injection. Oocytes, which matured in vitro either in modified porcine oocyte medium (IFP) or modified NCSU23 medium, were inseminated in PFM for 8h with either 0.5 (huKO, GalT-KO) or 1.6 (HNF-1α)×10(6) progressive motile spermmL(-1). The in vitro fertilized oocytes were cultured in porcine zygote medium-5 (Research Institute for the Functional Peptides) for 5 to 6 days until they were transferred. Some of these oocytes were examined for their fertilization rates. Blastocysts were transferred into the uterus of the recipient 150h after hCG treatment. The fertilization rates for huKO, HNF-1α and GalT-KO sperm were 63.5% (61/96), 62.5% (70/112) and 92.4% (61/66), respectively; 50.8% (31/61), 82.9% (58/70) and 60.7% (37/61) of these were monospermic. The rate at which the IVF embryos developed into blastocysts was 47.8-52.4%. This study demonstrates that IVF using frozen epididymal sperm is more efficient method for reproducing genetically modified pigs than AI (87.5 v. 33.3%).Reproduction Fertility and Development 12/2012; 25(1):309-10. · 2.58 Impact Factor
- Questions & Answers
- Open Reviews