The production of insoluble glucan was affected by the concentration of ions and buffers in a mouth. In this study,the effects of ions and buffers on the mRNA expression of gtfB and gtfC gene of Streptococcus mutans which is an importantcausative agent of dental caries were investigated by Fluorescent in situ hybridization(FISH). The mRNA of gtfBand gtfC gene was normally expressed in the BHI broth containing 1 % sucrose. The gtfB and gtfC mRNA expression wasincreased at 0.25 mM and 4 mM of CaCl2, respectively. While the mRNA expression of two genes was inhibited at eachconcentration of KCl and MgCl2 when compared to the control. As for buffers, the gtfB and gtfC mRNA expression waslower than the control by the addition of sodium bicarbonate. The addition of sodium phosphate decreased the gtfBmRNA expression except for 100 mM in which the expression was increased, and the gtfC mRNA expression was similarto or lower than the control at each concentraion of sodium phosphate. The mRNA expression of the gtfB and gtfC wasdecreased at each concentration of potassium phosphate when compared to the control.

The purpose of this study was to observe the histopathologic tissue reaction in vital bone in applying the varioustreated implants. For this purpose, twelve New Zealand Albino rats, weighing 3.3 to 4 kg were used as experimentalanimals. All the experimental groups divided into four groups; Machined surface as control, RBM(resorbable blast media),Hydroxyapatite-sand and Porous coating groups. All the experimental implants were examined under the scannningelectron microscope. All the experimental rabbits were implanted in the tibial metaphyses of rabbits under the generalanesthesia with Ketamine HCl(2.5ML /kg.body wt.) injections. For prevention of infection after implant, prophylactic erythromycineinjections, 250mg/body wt.(Aldrich Co. USA) were performed on each. On the sixth week after implant, allthe experimental rabbits were sacrificed with over dose of Sedaject(Samwoo Pharm .Co. Korea). All the tissues containingeach experimental materials were fixed in ethyle alcohol, and embedded in spurr resin(Polytechnic Co. USA) as usualmanner. sectioned in 12 um thickness, grinded , stained with the Vulenueva's osteochrome stain methed and examinedhistopatholgically. For measuring the distances between the implant and bone without any connective tissue interface,all the distances were calculated the length of the implant direct contact to bones. using the view analyzer program(Korea Optical Co.) and the statistical analysis were performed using the one-way ANOVA test. The statistical differenceswere considered significant below 5% level. Following results were obtained. On the scanning electron microscopicexamination, dull cracked continuous linear indentations were revealed on the machined surface implant, irregularsharp indentation on the resorbabale blast, irregular thin exophytic or indentated leaflets on the hydroxyapatite-sandimplant, and long ovoid globular particles were revealed on the porous coating implant surface respectively. On the histopathologicexamination, complete osseointegation was noted between the implant and cortex bone on the collar and theapex lesion and in parts, small newley formed bone spicules attached to the screws in marrow tissues with compatibilityin all experimental groups, but on the aspect of the tissue compatibility to the various implant materials, the superiorityof the materials could not identified. The ratio of drect contact between the bone and implant, the HA sand gorup wasthe most superior among the gorups and followed by the machine surface, but on RBM and porous coating groups wereinferior compared to that on the experimental groups. With these results, the superiority of tissue compatibility amongthe experimental implant group could not be identified.

Extensive oral mucosa loss from a variety of conditions is associated with significant functional morbidity andmortality. Although it is known that keratinocytes are a rich source of wound healing promoting factors such as transforminggrowth factor-β1(TGF-β1), it is not clear whether differentiated keratinocytes in a multi-layer form releasethis multi-functional growth factor. This study examined the hypothesis that keratinocytes in mono- and multi-layerforms expressed different levels of TGF-β1. When NHOK reached confluency in serum free medium(KBM), in test mediumcontaining 1.2 mM Ca++ KBM NHOK were allowed to form multi-layers and differentiate.The purpose of this study were to investigate the mRNA level of TGF-β1, FGF-2, and TIMP-1 by RT-PCR analysisand also to evaluate the expression of TGF-β1 and involucrin in keratinocytes at different times of the onset ofdifferentiation. The numbers and sizes of these nodules were increased as the process of keratinocyte differentiationproceed. Cultured NHOK in preconfluency under KBM medium expressed a significantly higher level of TGF-β1 relativeto those grown in multi-layer forms, while the level of TGF-β1 mRNA gradually reduced to its lowest level at 7 days ofgrowing cells in test medium. Cultured NHOK in preconfluency of KBM medium expressed a lower level of FGF-2 andTIMP-1 relative to those grown in multi-layer forms, while the level of FGF-2 and TIMP-1 mRNA showed the highestlevel at 3 days at gradually reduced to its lowest level at 7 days of growing cells in test medium. As a differentiationmarker for keratinocytes at different time points, the highest level of involucrin mRNA expression was found at the laterstage of cell differentiation. It suggested that the expression of TGF-β1 mRNA be consistent with the expression ofFGF-2 and TIMP-1 mRNA in NHOK grown in high calcium medium during the terminal differentiation. But differentiatedNHOK expressing higher involucrin mRNA could show constant espression of TGF-β1, FGF-2 and TIMP-1.

Gemcitabine (Gemzar, 2,2-difluorodeoxycytidine, or dFdC) is an analog of cytosine arabinoside with anti-tumor activityin a few human cancers (lung, ovary, pancreatic and breast cancers). However, the mechanism of apoptosis by thiscompound in carcinoma has not been fully elucidated. In the present study, we investigated that gemcitabine alone andcombination with cisplatin or 5-FU are cancer toxicity using lung cancer cell line A549 by MTT, FACS analysis, andWestern blot assay. Also, to confirm enhanced antitumor activity in vivo using an xenograft tumor model. The MTT assayshowed higher cytotoxic effect in combination with gemcitabine-cisplatin or gemcitabine-5-FU than gemcitabinealone. FACS analysis showed that gemcitabine-cisplatin combination increased hypodiploid DNA to 70.84 %. The inductionof apoptosis showed more increase in combination with gemcitabine-cisplatin or gemcitabine-5-FU than gemcitabinealone. The Western results showed higher expression of p53 and p21WAF/CIP1 protein in combination treatment withgemcitabine-cisplatin or gemcitabine-5-FU than gemcitabine treatment alone. But, Bcl-2 protein expression decreased.In vivo experiments showed that more decreased tumor size and more increased survival rate on combination with gemcitabine-cisplatin or gemcitabine-5-FU combination than gemcitabine alone. In conclusion, this study suggests thatgemcitabine combined with cisplatin or 5-FU are the synergistic effect of anticancer therapy on lung cancer.

The purpose of this study was to evaluate the role of c-fos and c-jun expression in the odontogenic cysts. For thisstudy, 20 subjects of odontoenic dysts: 8 subjects of keratocysts and 12 subjects of periodontal cysts referred to theDept. of Oral Pathology, School of Dentistry, Kyung Hee University, were used as experimental group, and 5 subjects ofnormal oral mucosa without any inflammatory changes. were used as control groups respectively. All the tissues of experimentaland control group were fixed in neutral formalin solution and embedded in paraffin, serial tissue section weremade 5㎛ in thickness and processed in the standard way for immunohistochemical method, using primary antibodies, forc-fos, c-jun was diluted at 1:100 each, followed by the super sensitive non-biotin horse radish peroxidase system withDAB as chromogen application, counter stained with Gill's hematoxylin stainmethod, mounted. And examined under thebiologic microscope with the criteria of -(no epithelial stain), +(weak or focal epithelial stain), ++(moderate or focal intensiveepithelial stain), +++(intense generalized epithelial staining) for the epithelial, and stromal tissues on each.Attained results as follows. In normal oral mucosa, it is noted that moderate positive responses in cytoplasm and nucleito c-fos and c-jun protein on each.. In the responses to c-fos, c-jun protein, moderate positive responses in nuclei andcytoplasms of the epithelial lining in keratocysts and periodontal cysts, but more intense reaction is noted on the periodontalcyst compare to that on the keratocysts. In the responses to c-fos, c-jun, it is noted that more intense responsesin odontogenic cyst compare to that in the oral mucosa. In the responses to c-fos and c-jun on submucoas oforal normal mucosa, focal epithelial stain was noted. and more intensive reaction was noted on the odontogenic cysts,most in periodontal cysts. This results suggests that c-fos and c-jun protein effected on the induction of developmentand growth of the cysts

Combined epithelial odontogenic tumors are very rare and represent hybrid lesion comprising adenomatoid odontogenictumor intermixed with calcifying epithelial odontogenic tumor. The authors present 3 cases of combined epithelial odontogenictumor which contained diagnostic areas for both adenomatoid odontogenic tumor and calcifying epithelial odontogenictumor. Their behaviour and histogenesis were discussed.

The purpose of this study is to investigate the relationship of periodontal disease to self-reported history of stroke in theelderly(60 years of age and older) with a special emphasis on elderly women. Data from the Third National Health andNutrition Examination Survey(NHANES III), a large population-based cross-sectional survey of the United States, were utilizedfor this study. Since we have 1,563 edentulous subjects from a total of 5,123 subjects and periodontal disease is a majorcause of tooth loss, it was necessary to account for this in our statistical analysis. Hence, we developed a new index calledthe Periodontal Health Status(PHS) index. In the logistic regression models with stratification by gender, males did not showstatistically significant relationship between Periodontal Health Status(PHS) and stroke history. In contrast, females showedsome marginal association between Periodontal Health Status(PHS) and stroke history. Further longitudinal interventionstudies need to be conducted to determine the temporal relationship between periodontal disease and stroke.

Annexin I plays an important role in the process of keratinization as a compont of the cornified envelope of skinepithelium. The effect of annexin I on the terminal ifferentiation of normal human oral keratinocyte(NHOK) have remainedto be defined. To understand the role of annexin I on the terminal differentiaiton of NHOK, NHOK and NHEK cells wereprimarily cultured in KBM bullet kit. When the cells reached confluence, terminal differentiation was induced by switchingthe medium to KGM bullet kit containing 1.2mM Ca2+. Preconfluency of NHOK under 0.05mM Ca++ conc as control groupwas used. The cells was examined with inverted microscope. Under 0.05mM Ca++ conc(Precon, Postcon), and 1.2mM Ca++conc(Postcon), RT-PCR for annexin I mRNA measurement, and immunoblotting for annexin I protein measurements in triplicate,respectively. The purpose of this study were to study differential mRNA & protein expression of annexin I betweenNHOK & NHEK by using RT-PCR & immunoslot blotting during terminal differentiation, and to apply these results to studya role of annexin I on epithelial differentiation of oral mucosal diseases in the future. Cultured NHEK showed larger area ofcellular stratification than cultured NHOK in 1.2mM Ca ++ concentration. Annexin I mRNA and protein expression of culturedNHOK showed higher than that of cultured NHEK in higher calcium concentration. Annexin I mRNA and protein expressionof cultured NHOK showed about 2-2.7 fold higher in 1.2mM Ca++ conc. than in 0.05mM Ca++ conc. Although annexinI was involved in the terminal differentiation of cultured NHOK & NHEK in higher calcium concentration, annexin Iplay an important role in the terminal differentiation of cultured NHOK in higher calcium concentration. From the abovingresults, It was suggested that annexin I would play an important role in the terminal differentiation of NHOK in higher calcium,which be helpful to study epithelial differentiation of oral mucosal diseases.

Hereditary dentin defects consist of dentin dysplasia(DD) and dentinogenesis imperfecta(DI). The DI associated with osteogenesisimperfecta has been classified as DI type I, whereas isolated inherited defects have been categorized as DI types IIand III. However, whether DI type III should be considered a distinct phenotype or a variation of DI type II is debatable.Recent genetic findings have focused attention on the role of the dentin sialophosphoprotein(DSPP) gene in the etiology ofinherited defects of tooth dentin. We have identified a novel mutation(c.727G → A, p.D243N) at the 243th codon of exon 4 ofthe DSPP gene in a Korean patient with DI type III. The radiographic and histologic features of the patient revealed theclassic phenotype of shell teeth. These findings suggest that DI type II and III are not separate diseases but rather the phenotypicvariation of a single disease.

In order to perform the protein analysis using the paraffin sections previous fixed with formalin, we applied theImmunoMemBlot (IMB) method1) to detect the epitopes of target proteins with specific antibodies. In this study the proteinextracts were obtained from the paraffin sections of each representative case of ameloblastoma, adenomatoid odontogenictumor (AOT), and normal gingiva, and more a protein extract from fresh tissue of ameloblastoma was also compared toevaluate the IMB results used with 24 different antibodies. First of all, in the comparison between the paraffin section extractand fresh tissue extract of ameloblastoma, the latter consistently showed more positive IMB reaction than the former.Meanwhile, the paraffin section extract of ameloblastoma was more comparable with that of normal gingival, disclosing thatmost of proliferating genes, oncogenes, and apoptosis related genes, i.e., PCNA, CDK4, c-erbB2, CEA, p53, Bax, Bad, FLIP,FAS, Bcl-2, p21, N-ras, MMP-2, MMP-9, caspase-3, -8, -9, were highly expressed in ameloblastoma, but EGFR, HGF, andVEGF were similarly expressed both in the ameloblastoma and in normal human gingiva. On the other hand, the comparisonbetween ameloblastoma and AOT both in the immunohistochemistry and IMB using their paraffin section extracts clearlydemonstrated that the ameloblastoma showed more expression of proliferating genes and oncogenes while the AOT showedmore expression of apoptosis related genes, i.e., Bax, Bad, FLIP, and caspase-9. Taken together, these data suggest thatthe IMB can be used for the primary screening of quantitative protein analysis using the paraffin section extract, and thatthe IMB results could be evaluated in conjunction with the immunohistochemical observation.

Polo-Like Kinase(PLK) is a cell cycle-regulated, cyclin-independent serine/threonine protein kinase. Recent reports haveshown a critical role for PLK during tumorigenesis. To explore whether PLK plays a general role as a tumor marker of oralsquamous cell carcinomas, we examined the expression of PLK mRNA and protein in oral squamous cell carcinoma cells andimmortalized normal oral keratinocytes(INOK). We also investigated that PLK mRNA was expressed in specimens from4NQO-induced SD rat tongue carcinomas using in situ RT-PCR methods. Immunocytochemically, most of the PLK was highlyexpressed in the nucleus of carcinoma cells, but not INOK. RT-PCR revealed PLK1 mRNA was detected in the FaDu and Hep2cancer cells, but no detected in the INOK. In situ RT-PCR revealed PLK1 mRNA expression increased sequentially from hyperplasiato dysplasia, and squamous cell carcinoma during the malignant progression. PLK1 expression could reflect the degreeof malignancy and proliferation in oral squamous cell carcinomas. Thus, in addition to being of diagnostic value, modulationof PLK1 activity in the tumors by chemotherapeutic agents or gene therapy may prove to be of therapeutic value.

The tumor suppressor gene, phosphate and tensin homologue(PTEN) has been shown to dephosphorylate the phosphatidylinositol3-kinase(PI 3-K)-generated phosphatidylinositol(3-5)-triphosphate in vivo, thus interfering with the potentiallyoncogenic signals emanating from PI 3-K. Promoter hypermethylation of CpG islands has recently been shown to be an epigeneticchange resulting in loss of function in some genes involved in cell cycle regulation and DNA repair.Immunohistochemal staining for monoclonal antibody 6H2.1 was performed from paraffin embedded blocks of 20 benign epitheliallesions and 40 head and neck squamous cell carcinomas(HNSCCs). Immunoreactivity was graded semiquantitatively byconsidering the percentage and intensity of the staining of the tumor cells. Also, this study tried to identify PTEN methylationin benign epithelial lesions(24 cases) and HNSCCs(44 cases of paraffin embedded blocks, 4 cases of frozen tissues) usingmethylation-specific PCR(MSP). In HNSCCs, immunoreactive scores of stage 1 and 2(12 cases, average score 85.2) werehigher than those of stage 3 and 4(15 cases, 41.9) and statistically significant(P=0.017). Immunoreactive scores of moderateand poorly differentiated carcinomas(22 cases, 61.6) are more or less lower than those of well differentiated carcinoma(15cases, 87.0) but not significant(P=0.361). Among 24 cases of benign epithelial lesions, 12 cases showed unmethylated PTENbut none methylated. In HNSCCs, 22 of 44 paraffin embedded blocks showed unmethylated PTEN but none methylated, andall 4 frozen tissue revealed unmethylated PTEN, one of which(25%) methylated. We consider that the loss of PTEN proteinexpression may be associated with the progression of HNSCCs and the other alteration rather than methylation may be importantin the inactivation of PTEN in HNSCCs.