A custom-made microarray for Porphyromonas gingivalis was constructed to investigate the gene expression profiling during its in vitro growth. There was a strong positive correlation between the results of both microarray and quantitative real-timePCR analyses (r=0.910, p<0.01). Many transcripts changed dramatically during the late-log to theearly stationary phase. In a stationary phase, most of the transcripts decreased. However, transcripts related to the transposon function, oxidative stress, and energy metabolism were increased or sustained at high levels. More notably, the transcripts related to protein folding and protein stabilization, such as dnak, groEL, groES, and htpG, increased significantly after 10h in the stationary phase, suggesting that these chaperone proteins may play an important role in bacterial survival. All together, our custom array is useful for transcriptional research for P. gingivalis. It provides that the gene expressions are growth phase-specific and are changed dramatically in response to environmental change during bacterial culture.

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The present study performed a histological and lectin histochemical investigation in order to clarify the adult human anterior lingual gland, and to obtain the fundamental findings for comparative study with anatomy and salivary gland diseases. Lingual tissues were obtained from six autopsy cases. All the specimens were fixed in a 10% neutral formalin solution, and paraffin sections were made by the usual method. They were stained with hematoxylin and eosin, and PAS-alcian blue pH 2.5. Using seven kinds of lectins, the avidinbiotin peroxidase complex was done. The anterior lingual glands were located between muscle fibers in the inferior aspect of the lingual apex. The anterior lingual glands were made up of mucous-rich mixed glands; Alcian blue pH 2.5 and/or PAS mixed positive mucous acinar cells, PAS positive serous acinar cells, and ductal cells were observed. Aging and/or inflammatory changes such as mild adipose infiltration(three cases), mild lymphocyte infiltration(one case), mild acinar atrophy(one case), and both mild adipose and moderate lymphocyte infiltrations(one case)were recognized, respectively. Mucous and serous acinar cells and ductal cells showed various degree positivity to all lectins(Con A, DBA, PNA, RCA-I, SBA, UEA-I and WGA).The results indicated that mucous acinar cells having neutral and acid mucopolysaccharides and serous acinar cells having glycogen and ductal cells contained D-mannose, Dglucose, N-acethyl galactosamine, D-galactose, L-fucose, N-acetyl-D-glucosamine and Nacetyl neuramic acid.

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The dental follicle is an ectomesenchymal tissue that surrounds developing tooth germs, which contains osteoblastic/cementoblastic lineage committed stem/progenitor cells. The purpose ofthis study is to examine the gene expression and the protein production of leukemia inhibitory factor(LIF)in human dental follicle cells(hDFC)and to regulate these at the post-transcriptional level by miRNA targeting. We examined the kinetic gene expression ofLIF in hDFC cultured with mesenchymal stem cell osteogenic induction medium(MSCOIM)on days 0, 1, 2, 4, 7 and 11 using real-time PCR. Expression was decreased in MSCOIM culture in a time-dependent manner. LIF protein levels decreased until culture day 2, and then increased until day 4 in MSCOIM culture. These results suggest that LIF expression is regulated at the post-transcriptional level, and may be affected by microRNA(miRNA). To demonstrate the direct role of specific miRNAs in the modulation of LIF production, we transfected hDFC with miRNA mimics offour miRNAs predicted to target LIF; hsa-miR-29b, hsa-miR-125a, hsa-miR-199- 5p and hsa-miR-199-3p. After transfection, the production of LIF was significantly lower in the cells transfected with miRNA his-miR-29b, but hsa-miR-125a, hsa-miR-199-5p and hsamiR-199-3p showed no significant changes in LIF production. These results suggest that production ofLIF is partially regulated by miRNA, maintaining the undifferentiated status of hDFC and influencing differentiation toward the osteoblastic/ cementoblastic lineage.

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Mucous cysts of the maxillary sinus are a pathological entity caused by dilatation and disturbance of ducts within the sinus mucosa resulting from damage or blockage of the ducts of seromucous nasal glands. There has been little histopathological and immunohistochemical research about the characteristics and onset mechanism of these cysts, until now. The present study was to investigate the mucous cysts of the maxillary sinus in order to understand their nature and genesis. Mucous cysts of the maxillary sinus were rare, occurring in seven cases(4.1%)among the 171 cases with cysts in the maxillary sinus. Four of the cases had cysts corresponding to primary cysts, and three cases corresponding to secondary cysts due to some treatments. Histologically, the extravasation type cysts of six cases showed a lot of mucoid material in connective tissue with mucinophage, lymphocyte, plasmacyte, and eosinophilic inflammatory cell infiltration and then mucous granuloma formation, and bleeding. In the retention type cyst of one case, the inner surface of the cyst was covered with ciliated columnar, cuboidal epithelium and sometimes apocrine metaplasia including mucoid material in it. Immunohistochemically, IgG and IgA positive plasmacytes were seen most often, and these cells were thought to contribute to the humoral immunity. There were also some IgEpositive cells(3 cases)only associated with mast cells, which had the relationship of type I allergy. Anti-GCDFP-15 antibody was observed not only in apocrine metaplasia cells, but also in existing dilated and hyperplastic ductal epithelial cells in the extravasation type. Anti-GCDFP-15 was thought to have a cross relationship to dilatation and hyperplasia of the cyst.

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Orthodontically induced inflammatory root resorption (OIIRR) is a common complication associated with orthodontic tooth movement. The aim of this study was to investigate how dental pulp contributes to root resorption during orthodontic tooth movement. Fifteen male 8-week-old BALB/c mice were subjected to an excessive orthodontic force of 25g to induce a mesially tipping movement of the upper first molars for nine days. The expression levels of the TRAP, interleukin(IL)-17, IL-17 receptor(IL-17R), IL-6 and keratinocyte chemoattractant (KC; IL-8-related protein in rodents) proteins were determined in dental pulp (DP) by an immunohistochemical analysis. Furthermore, the effects of IL-17 on the production of IL-6 and IL-8 were investigated using human dental pulp (hDP) cells in vitro. Resorption lacunae with multinucleated cells were observed in the 25g group during the in vivo experimental tooth movement study. Immunoreactivity for IL-17, IL-17R, IL-6 and KC was detected in all of the DP tissues subjected to the orthodontic force on day nine. Moreover, IL-17 increased the release of IL-6 and IL-8 from hDP cells. The results of this study suggest that the IL-17 may aggravate the process of root resorption by increasing the production of IL-6 and IL-8 from hDP cells.

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Remodelling of the periodontium after application of mechanical forces constitutes the basis of clinical orthodontics, and various immunoregulatory molecules are involved in this process. The present study focused on the localizations of the tumor necrosis factor-α(TNF-α)and macrophages in periodontalligament(PDL)during experimental tooth movement in rats. A total of 15 male 6-weeks-old Wistar rats were subjected to an orthodontic force of 10g to induce a mesially tipping movement of the upper first molars. Experimental tooth movement was accomplished for seven days. We determined the localization of TNF-α and RM-4(an antibody specific for identification of macrophages)in the PDL during orthodontic tooth movement using immunohistochemistry. Immunoreactivity for TNF-α and RM-4 was detected in PDL fibroblasts in the compressive side by the orthodontic force of 10g. On the first day after tooth movement, the immunoreactivity of TNF-α and RM-4 was weak. On the third and fifth days, more TNF-α and RM-4 positive reactions in some nucleuses of fibroblasts were recognized than on the first day. Furthermore, these positive reactions were decreased after seven days. Therefore, RM-4 (+)cells involved in the expression of TNF-α may play an important role in the initial reaction of the PDL and in the induction of the osteoclastic bone resorption during orthodontic tooth movement.

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Rothia dentocariosa and Rothia mucilaginosa, which are opportunistic pathogens that are capable of causing serious infections, inhabit the oral cavity. However, there is no suitable method for assessing the prevalence of Rothia species in the oral cavity. In this study, four polymerase chain reaction(PCR)primers were designed based on partial sequences of the 16S rDNA genes of the abovementioned oral Rothia species. These primers react to the oral Rothia species and did not react to other Rothia species except Rothia aeria. Moreover, representative non-Rothia oral bacteria displayed negative reactions to these primers. These results indicate that these primers are useful for identifying R. dentocariosa and R. mucilaginosa. We also developed a simple multiplex PCR procedure involving the two primer pairs designed in the present studyas a rapid and reliable method of identifying known oral Rothia species.

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Repetitive transcranial magnetic stimulation(rTMS)of the primary motor cortex has been reported to be effective for the treatment of various types of neuropathic pain. However, the clinical effects of rTMS for the treatment of post-stroke pain are unclear. The present study investigated rTMS-induced analgesia in patients with post-stroke pain, and the clinical use of rTMS in the treatment of post-stroke pain is discussed. Changes in a visual analog scale(VAS)measuring pain following rTMS(sham and real)of the primary motor cortex(frequency 5Hz, at 100% resting motor threshold, 500 pulses per session)were examined in 20 post-stroke pain patients. No side effects related to rTMS were observed. The real rTMS significantly reduced the patientsʼ VAS scores immediately after rTMS, and the score reduction persisted for 300 min after rTMS(p<0.05, ANOVA).These results indicate the usefulness of rTMS for the treatment of post-stroke pain with a high amount of safety.

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Green tea is an aqueous infusion of the dried unfermented leaves of Camellia sinensis (family Theaceae), for which numerous biological activities have been reported, including antimutagenic, antibacterial, hypocholesterolemic, antioxidant, antitumor and cancer preventive activities. Aggregatibacter actinomycetemcomitans is implicated in the etiology of aggressive periodontitis and chronic periodontitis. We previously reported that LPS from Aggregatibacter actinomycetemcomitans(Aa-LPS)had strong cytotoxic effects against human leukemia cell lines(HL60 cells, THP-1 cells)and human gingival fibroblasts. The purpose of this study was to investigate the anticytotoxic effect of green tea catechin on Aa-LPS. When the cell, Aa-LPS, and the catechin components(EGCg, ECg, C and GC)were incubated, EGCg and Cg showed a strong anticytotoxic effect on Aa-LPS. Furthermore, when the catechin-pretreated cells and Aa-LPS were incubated, EGCg and Cg showed a strong anticytotoxic effect on Aa-LPS. Thus, it was suggested that the gallate moiety included in green tea catechins showed anticytotoxic effects against LPS from Aggregatibacter actinomycetemcomitans.

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Among the genus Rothia, R. dentocariosa and R. mucilaginosa have been isolated from the human oral cavity. Currently, we reported that new selective media were developed for the isolation of each species. The clinical efficacy of the genus Rothia was evaluated from samples of oral cavities, such as pit and fissure plaque, buccal surface plaque, the buccal membrane surface, the dorsum of tongue, gingival crevicular fluid (GCF), and the mucosal surface of denture base using these selective media. R. dentocariosa and R. mucilaginosa were detected in all sites from pit and fissure plaque, buccal surface plaque, the buccal membrane surface and the dorsum of tongue. Therefore, both Rothia species are common members of oral cavity. R. mucilaginosa was predominant at the dorsum of tongue with 28.15% to total streptococci. Results show that the dorsum of tongue is the main habitation area of R. mucilaginosa. R. dentocariosa and R. mucilaginosa were also detected in GCF. These bacteria were detected to a certain extent on the mucosal surface of denture base. Therefore, it seems that these bacteria are members of denture plaque.

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There have been numerous reports on the effects of the reduced masticatory function on jawbone growth, but the types of changes that occur during each period remain unclear. The objective of this study was to elucidate the effects of the reduced masticatory function on the jawbone over time. Micro-computed tomography (micro-CT) was used to scan the heads of rats that underwent extraction of all maxillary molars at the age of 5 weeks and were reared on a powdered diet, and the heads of control rats that did not undergo molar extraction and were reared on a solid diet. The changes in jawbone morphology up to 20 weeks were investigated in both groups. There were no significant differences in the maxillary or mandibular size, but the mandibular ramus length was significantly smaller in the extraction group from 9 weeks to 20 weeks, while the mandibular angle was significantly larger from 7 weeks to 20 weeks. The mandibular area was also significantly smaller from 7 weeks to 20 weeks, the area of the mandibular notch was significantly larger from 7 weeks to 20 weeks, and the mandibular thickness was significantly smaller from 9 weeks to 20 weeks. These results suggest that the reduced masticatory function affects mandibular growth and development from 2-4 weeks after molar extraction.

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Infective agents are abundant in hospitals, and so medical staff members are often exposed to them. Although previous studies have highlighted the role played by the nasal flora of medical staff in the development of nosocomial infections, few studies have specifically investigated this issue. Six volunteer medical staff members, who worked at Nihon University Hospital at Matsudo, participated in this study. Nasal samples were obtained from the medical staff, and then the samples were cultured and evaluated using routine bacteriological study methods. Staphylococci were detected in the nasal samples of all of the medical staff. Staphylococcus epidermidis was the predominant species in their nasal cavities(71.3%). None of the medical staff had been infected with methicillin-resistant Staphylococcus aureus(MRSA), but four of six staff members possessed methicillinresistant coagulase-negative staphylococci(MR-CNS).Medical staff members are both at risk of infection and also a potential source of nosocomial pathogens such as methicillin-resistant staphylococci. As a preventive measure against nosocomial infection, it might be necessary to continuously investigate the frequency of methicillin-resistant staphylococci in the nasal cavities of medical staff.

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Background: We encountered a rare case of central giant cell granuloma(CGCG)in association with neurofibromatosis type 1 in a middle-aged Asian woman. Most reported cases involve isolated central giant cell granuloma or neurofibromatosis type 1(NF1), and concurrence of these two entities is very rare.Methods: We report a case of concurrent central giant cell granuloma with neurofibromatosis type 1. Thorough clinical and radiological examinations were performed.Result: After diagnosis of possible concurrent central giant cell granuloma with neurofibromatosis, surgical excision with curettage was performed. Based on histopathological and clinico-radiological findings, the final diagnosis was central giant cell granuloma with neurofibromatosis 1. Follow-up at 1 year did not show any recurrence.Conclusion: We review the proposed mechanisms underlying the apparent association between CGCG of the jaws and neurofibromatosis 1. This case could represent either a coincidental association or a true genetic linkage; the mechanism in the present case appears most likely related to NF1-related osseous dysplasia.

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