Cloning, Molecular ; methods ; Dental Caries ; immunology ; prevention & control ; Forecasting ; Humans ; Research ; trends ; Research Design ; Vaccination ; Vaccines ; genetics ; immunology

0.05) after condensation. The difference of leakage between A and B, B and D groups was significant from 20 and 15 days on. The glucose concentration in group A and B was higher than that in group C and D during the corresponding observation period and using the corresponding sealer materia.AH Plus resulted in less leakage than Pulp Canal Sealer EWT did when using lateral condensation technique and two sealer performed the same when using vertical condensation method.Conclusions:The sealing ability of vertical condensation technique is better than that of lateral.

Objective: To examine effects of Platycodon grandiflorum (JG), Glycyrrhiza uralensis Fisch (GC) or the compound of JG with GC on the growth of cariogenic and periodontopathic bacteria in vitro . Methods: JG,GC and the compound were extracted with ?=65% ethanol respectively. The minimal inhibitory concentration(MIC)and minimal bactericidal concentration (MBC) of JG, GC or compound against S.mutans MT818, S. sobrinus 6715, P.gingivalis 381 and B.forsythus 43037 were measured by drug sensetivity test.Results: JG showed no effect on the growth of oral pathogens tested;GC inhibited S.mutans MT 8418 and S.sobrinus 6715 with MIC of 3.91 mg/ml.The compound inhibited the microorganisms with the MIC of 1.96 mg/ml against S.mutans MT8148 or S.sobrinus 6715, 3.91 mg/ml against P.gingivalis 381, 7.81 mg/ml against B.forsythus 43037 respectively.Conclusion: The compound of JG and GC has stronger inhibition and bactericidal effects on oral pathogens than the single medicine.

Objective:To compare the antibiotic effects of 400 g/L chlorhexidine(CHX) varnish on different teeth surfaces. Methods: 400 g/L chlorhexidine(CHX) varnish was applied onto the left mandibula r first molar once in 5 young volunteers (group 1) or twice with a interval of I week in another 5 (group 2). The right mandibular first molar was served as th e control.Plaque samples from fissure or approximal surface were taken for Str eptococci mutans (S.mutans) detection with routine bacteriologic procedure onc e a week for 16 weeks. Results: In group 1 S.mutans in the plaque in fissue was significantly suppressed from 1 to 4 weeks after the v arnish application (P

OBJECTIVEThe soluble protein recombinant Streptococcus mutans surface protein (rPAc) was expressed in Escherichia coli (E.coli) after the optimization of inducing conditions. The antiserum against rPAc was obtained by immunizing mice with the purified rPAc.

METHODSThe soluble expression of rPAc in E. coli was further optimized by means of different culture conditions. Polyclonal antibody was made by immunizing mice with purified rPAc. Western blot and enzyme linked immunosorbent assay (ELISA) were carried out to identify the immunocompetence of the antibody.

RESULTSThe highest soluble expression level of rPAc was obtained at Luria-Bertani (LB) medium (pH=7.2) when optical density (OD600nm) was 0.6 after being induced at 30 degrees C for 4 h and the concentration of isopropyl beta-D-1-thigalactopyranoside (IPTG) was 1.0mmol x L(-1). The titer of the mice antiserum against rPAc was about 1:6000 by ELISA analysis, and rPAc could be specifically recognized by Western blot analysis.

CONCLUSIONThis study proved that rPAc can be effectively expressed as a soluble form in E. coli, and the high specific polyclonal antibody of rPAc was proved to be prepared, which shed light on further research of DNA prime-protein boost inoculation.

Animals ; Antibodies ; Blotting, Western ; Enzyme-Linked Immunosorbent Assay ; Escherichia coli ; Membrane Proteins ; Mice ; Recombinant Proteins ; Streptococcus mutans

Objective To explore the preparation and quality control of As2 O3 nanoparticle .Methods PEG‐PLA was used as the vector material to prepare As2 O3 nanoparticle with ultrasonic emulsification method ,and the VEGFR‐2 was coupled to obtain VEGFR‐2/As2 O3‐PEG‐PLA nanoparticle .The particle size distribution ,Zata potential ,loading efficiency (LE) ,encapsulation effi‐ciency(EE) ,drug release in vitro and stability was determined ,and morphological characteristics was observed by transmission elec‐tron microscope(TEM) .Tweety‐four hepatocellular carcinoma nude mices were randomly divided into VEGFR‐2/As2O3‐PEG‐PLA nanoparticles group and As2 O3‐PEG‐PLA nanoparticles group ,by tail vein injection of nanoparticles .High performance liquid chro‐matography was used to determine content of As2 O3 .After 21 d ,six nude mices in each group were killed ,and the immunohisto‐chemistry and western blot method was used to detect the expression of VEGFR‐2 .Results The particle size of VEGFR‐2/As2 O3‐PEG‐PLA was determined to be (141 .9 ± 13 .2)nm ,Zata potential was (10 .2 ± 1 .1)mV .It was found to spherical or oval shape , with uniform size and dispersibility under TEM .LE and EE was (5 .51 ± 1 .83)% and (62 .12 ± 5 .98)% ,respectively .Drug release in vitro showed that VEGFR‐2/As2 O3‐PEG‐PLA exhibited controlled release effect ,with half of the release time as 10 h .Besides , VEGFR‐2/As2 O3‐PEG‐PLA showed a good stability in 3 days .Compared with As2 O3‐PEG‐PLA nanoparticles group ,the concen‐tration of As2 O3 in tumor and liver tissue was high ,the concentration of As2 O3 in blood ,heart ,kidney tissue was low ,the expression of VEGFR‐2 in tumor tissue was low in VEGFR‐2/As2O3‐PEG‐PLA nanoparticles group(P< 0 .05) .Conclusion The prepared As2 O3 nanoparticle using PEG‐PLA as vector and VEGFR‐2 as target showed uniform size ,high EE and LE ,good stability .And it preliminarily proved that VEGFR‐2 could be targeted in nude mice .

OBJECTIVETo investigate the effect of specific anti-streptococcus mutans IgY against streptococcus mutans on dental caries development in rats.

METHODS35 wistar rats were divided into 5 groups: group A received IgY gargle; group B received IgY lyophilized powder; group C received sterilized water as control; group D and E received egg yolk food with or without specific IgY individually. They were all fed with caries-inducing diet 2000#. The number of caries scores was counted by the procedure of Keyes'.

RESULTSThere was a significant lower mean of caries scores in groups treated with IgY lyophilized powder and gargle. By treating with egg-yolk food contained specific IgY, the mean of caries scores decreased comparing with no treatment group.

CONCLUSIONLocal passive immunization with specific anti-streptococcus mutans IgY may be an effective way to prevent the development of dental caries.

Animals ; Antibodies, Bacterial ; administration & dosage ; Dental Caries ; prevention & control ; Female ; Immunization, Passive ; Immunoglobulins ; immunology ; Male ; Rats ; Rats, Wistar ; Streptococcal Vaccines ; immunology ; Streptococcus mutans ; immunology

OBJECTIVESTo assess the efficacy of plasmid DNA encoding pac gene of Streptococcus mutans (S. mutans) intranasally immunized in gnotobiotic rats and to compare the effect of two different delivery systems.

METHODSSprague Dawley rats, infected with S. mutans at 20 days of age, were intranasally immunized with plasmid pCIA-P (group A), Dosper-DNA complex (group B), Bupivacaine-DNA complex (group C). Control rats were either immunized with plasmid pCI (group D), distilled water (group E) or immunized intramuscularly (group F). All the rats were boosted 2 weeks later. ELISA determined the antibodies against the vaccines. Keyes caries score was used to evaluate the anti- caries effectiveness of the vaccines at the terminal study.

RESULTSAs for the antibody reactions, there were significantly (P < 0.01) differences between rats immunized with DNA vaccine and non-immunized rats. And rats in group B and C had the significantly (P < 0.01) higher level of specific salivary anti-PAc IgA antibodies and rats (group B, C, F) had the significantly (P < 0.01) higher specific serum anti-PAc IgG responses to DNA vaccine. Keyes scores of rats (group B and C) were significantly (P < 0.01) lower than others.

CONCLUSIONSIntranasal immunization with plasmid pCIA-P encoding pac gene successfully reduces the caries and appears to be a promising approach against dental caries. Cationic liposome Dosper and local anesthetic bupivacaine could enhance the efficacy of DNA vaccine.

Administration, Intranasal ; Animals ; Antibodies, Bacterial ; blood ; Bacterial Proteins ; genetics ; Dental Caries ; prevention & control ; Female ; Immunization ; Immunoglobulin A ; blood ; Immunoglobulin G ; blood ; Membrane Glycoproteins ; Plasmids ; genetics ; Rats ; Rats, Sprague-Dawley ; Streptococcal Vaccines ; genetics ; immunology ; therapeutic use ; Streptococcus mutans ; genetics ; immunology ; Treatment Outcome ; Vaccines, DNA ; genetics ; immunology ; therapeutic use

OBJECTIVETo investigate the effects of transforming growth factor beta(1) (TGF-beta(1)) and bone morphogenetic protein 2 (BMP2) combined with heparin on odontoblast differentiation.

METHODSTrypsin-isolated dental papillae from day 17 mandibular first molar were cultured in semisolid-agar medium for 6d. Recombinant human TGF-beta(1) and BMP2 combined with heparin were added to the medium.

RESULTSTGF-beta(1) and BMP2 combined with heparin induced differentiation of odontoblasts and promoted matrix secretion. Odontoblast differentiation never occurred when TGF-beta(1) or BMP2 were added alone to the medium, whereas an increase in extracellular matrix production was observed.

CONCLUSIONThese results demonstrate that both TGF-beta(1) and BMP2 stimulate the cytological and functional differentiation of preodontoblasts, and that heparin might play important role as a substrate.

Animals ; Bone Morphogenetic Protein 2 ; Bone Morphogenetic Proteins ; pharmacology ; Cell Differentiation ; drug effects ; Heparin ; pharmacology ; Mice ; Odontoblasts ; cytology ; drug effects ; Transforming Growth Factor beta ; pharmacology ; Transforming Growth Factor beta1

OBJECTIVETo investigate the genotypic characterization of Porphyromonas gingivalis (Pg) and the heterogeneity of a potential virulence factor-PrtC.

METHODSArbitrarily primed polymerase chain reaction (AP-PCR) was applied to 80 Pg strains isolated from 24 unrelated Chinese periodontitis patients. PCR reaction was used to detect a fragment of the collagenase gene (PrtC gene). To evaluate the sequence heterogeneity of the Pg PrtC genes, sequence analysis of four PrtC gene of clinical isolates was performed.

RESULTSRandom primer OPA-05 and OPA-17 distinguished 7 AP-PCR profiles (I through VII). The majority of the strains belonged to type VII which accounted for 25.8%. A 548bp fragment of PrtC gene was detected from 24 clinical strains. The PCR products were verified by the restriction endonucleases PstI and PvuI. Sequence analysis showed 4 PrtC genes were heterogeneous in their nucleotide composition and differed from reference strain Pg 53977.

CONCLUSIONSThe results demonstrated genetic diversity existed among these clinical strains isolated from Chinese periodontitis patients and the PrtC genes are heterogeneous in their nucleotide sequence.

Adult ; Collagenases ; genetics ; DNA, Bacterial ; chemistry ; genetics ; Female ; Genetic Heterogeneity ; Humans ; Male ; Middle Aged ; Periodontitis ; microbiology ; Polymerase Chain Reaction ; methods ; Porphyromonas gingivalis ; genetics ; isolation & purification ; Sequence Analysis, DNA