Objective: To sequence V-region and P-region gene of surface protein of serotype c Streptococcus mutans clinical isolates with different adherent abilities. Methods: The clinical isolates of serotype c S.mutans included two groups with different spaP-pv AluI genotypes, which were derived from previous studies in our lab. The genome DNA was extracted. The spaP-pv (2 060-3 157 bp) was amplified by PCR, then sequenced and analyzed. Results: Seven sites of AluI 5′-AG↓CT- 3′were included in the sequences of spaP-pv of both genotypes strains. The sequences of spaP-pv of ten a-genotype strains were the same except several site mutations, and so were those of b-genotype strains. Two different DNA fragments were revealed between a and b geotype strains. And they were located in the V-region of spaP. Conclusion: The mutation of gene encoding V-region of S.mutans clinical isolates might be related to the differences of adherent abilities .

Objective:To investigate the relationship between Mutans streptococci (MS) transmission from mothers to children and its initial adherence properties.Methods:200 MS isolates were genotypied by AP-PCR to demonstrate transmission between 20 pairs of mother and child aged 3~4 years, and to detect the transmitted strains and non-transmitted strains of mothers. Then the adherence of the strains to salivary coated hydroxyapatite beads (SHA) were determined by 3H- thymidine incorperation assay.A restriction fragment length polymorphism (RFLP) study of the different regions(spap-a,spap-pv)of the spap were undertaken by endonuclease haeⅢ and AluⅠrespectively. Results:The transmitted strains showed weaker adherence properties than the non-transmitted strains (P

Objective:To investigate the gene expression variety of different genotype of F-ATPase subunit uncEBF in Streptococcus mutans (S.mutans) and to evaluate the relationship among uncEBF gene expression levels, genotypes and the acidurance ability of S.mutans. Methods:The relative expression quantity of uncEBF gene against the housekeeping gene recA was determined by the two-step method of semi-quantitative RT-PCR in 18 clinical isolates of S.mutans(7 with genotype A uncEBF and 11 with genotyp B,10 with high acidurance and 8 with low). A gel documentation system and QUANTITY ONES software were used to assay the data. Results:uncEBF mRNA expression level in the isolates with genotype A uncEBF was higher than that in those with genotype B(P

Objective:To discuss the active impact of the domestic breast X-ray machine upgrade at the diagnosis breast disease. Methods:After the transformation of domestic breast X-ray machine, adoption the IP board instead of the film cartridge, complete digital mammography system. Results:Computed X-ray imaging processing image quality is better than traditional X-ray photography piece, within two years, completed a total check of more than 400 patients, overall diagnosis rate more than 95%. Conclusion:Buy the CR system All levels of the hospital, Can take advantage of the existing the ordinary breast X-ray machine equipment, Carry out breast Digital Imaging System.

0.05);by the end of the experiment that was 24.5?1.05,28. 3?1.29,26.6?1.19,10.2?1.81, 26.3?1.54 and 27.3?1.38 respectively (D vs each of the other groups P0.05). Conclusion: Gene vaccines pcDNA3-pac and pcDNA3-gtfB have no unfavo rable influence on weight of gnotobiotic rats,while the inactive whole cell vac cine has.

OBJECTIVETo explore the relationship between salivary proteome and dental caries and to promote the biomarker studies of dental caries susceptibility by comparing the salivary proteome of caries-active children and caries-free children with electrospray ionization ion-trap tandem mass spectrometry (ESI-MS/MS).

METHODSTen caries-active children and ten caries-free children were sampled. The salivary proteome of the two groups was studied, and the differential protein between the two groups was analyzed by ESI-MS/MS after sodium dodecyl sulfate polyacrylamide gel electrophoresis, filter-aided sample preparation, and liquid chromatography.

RESULTSThe concentration of salivary protein was higher in the caries-active group than in the caries-free group. The polypeptide counts of thecaries-active and caries-free groups were 602 and 481, which belonged to 286 and 227 proteins, respectively. The differential polypeptide count of the two groups was 361, and the differential protein count was 118. The detected proteins included matrix metalloproteinase-9 (MMP9), mucin-7 (MUC7), lactotransferrin (LTF), carbonic anhydrase 6 (CA6), azurocidin (AZU), and cold agglutinin.

CONCLUSIONThe total salivary protein was higher in the caries-active group than in the caries-free group. The preliminary detection of differential proteins (MMP9, MUC7, LTF, CA6, AZU, and cold agglutinin) may lay some foundation for biomarker research of dental caries susceptibility.

Carbonic Anhydrases ; Child ; Dental Caries ; Humans ; Matrix Metalloproteinase 9 ; Proteome ; Saliva ; chemistry ; Spectrometry, Mass, Electrospray Ionization ; Tandem Mass Spectrometry

OBJECTIVETo investigate the mechanism of retinoic acid (RA) signal in dental evolution, RA is used to explore the influence of the mechanism on neural crest's migration during the early stage of zebra fish embryos.

METHODSWe divided embryos of wild type and transgenic line zebra fish into three groups. 1 x 10(-7) to 6 x 10(-7) mol x L(-1) RA and 1 x 10(-7) mo x L(-1) 4-diethylaminobenzaldehyde (DEAB) were added into egg water at 24 hpf for 9 h. Dimethyl sulfoxid (DMSO) with the concentration was used as control group. Then, antisense probes of dlx2a, dlx2b, and barxl were formulated to perform whole-mount in situ hybridization to check the expressions of the genes in 48 hpf to 72 hpf embryos. We observed fluorescence of transgenic line in 4 dpf embryos.

RESULTSWe obtained three mRNA probes successfully. Compared with DMSO control group, a low concentration (1 x 10(-7) mol x L(-1)) of RA could up-regulate the expression of mRNA (barx1, dlx2a) in neural crest. Obvious migration trend was observed toward the pharyngeal arch in which teeth adhered. Transgenic fish had spreading fluorescence tendency in pharyngeal arch. However, a high concentration (4 x 10(-7) mol x L(-1)) of RA malformed the embryos and killed them after treatment. One third of the embryos of middle concentration (3 x 10(-7) mo x L(-1)) exhibited delayed development. DEAB resulted in neural crest dysplasia. The expression of barxl and dlx2a were suppressed, and the appearance of dlx2b in tooth was delayed.

CONCLUSIONRA signal pathway can regulate the progenitors of tooth by controlling the growth of the neural crest and manipulating tooth development

Animals ; Branchial Region ; Cell Differentiation ; drug effects ; Embryo, Nonmammalian ; drug effects ; embryology ; metabolism ; In Situ Hybridization ; Neural Crest ; drug effects ; Odontogenesis ; Signal Transduction ; Tooth ; drug effects ; embryology ; metabolism ; Tretinoin ; pharmacology ; Zebrafish ; embryology ; genetics ; metabolism

OBJECTIVEThis study aims to investigate the expression of connexin 43 (cx43) gene during early development in zebra fish and provide a foundation for further research of cx43 gene in tooth development.

METHODSTotal RNA was extracted within 72 h after fertilization of zebra fish embryos and then reversed transcribed to generate the cDNA library. The specific fragments of the cx43 gene were then cloned and connected to the PGEMT vector. After confirming the constructed plasmid, the corresponding RNA polymerase was chosen, and the digoxin-labeled anti-sense mRNA probe of cx43 was synthesized in vitro. The cx43 gene expression of zebra fish indifferent stages was carried out by in situ hybridization. The relationship of the cx43 gene expression and anatomy of the pharyngeal teeth were compared by alizarin red staining.

RESULTSThe mRNA antisense probe of cx43 was acquired. The positive signal of sepia was observed in the different stages of zebra fish pharyngeal teeth after fertilization. After fertilization for 9 days, the expression site of cx43 in situ hybridization was overlapped in accordance with the anatomical site of the pharyngeal teeth.

CONCLUSIONcx43 gene participates in tooth development and mineralization process and plays a crucial role in later mineralization.

Animals ; Connexin 43 ; Gene Expression ; Genetic Vectors ; In Situ Hybridization ; Odontogenesis ; Plasmids ; RNA, Messenger ; Tooth ; Zebrafish

In view of the weakness of the teachers' strength, students' lack of interest and the lack of unity of teaching materials in the foreign language teaching, Oral Medicine College of Chongqing Medical University carried out the reform to the professional foreign language courses in the postgraduate education period by strengthening the preparation of special teaching materials, reinforcing teaching staff construction, reforming teaching methods and creating a learning environment. The results of teaching assessment by students and peer-reviewers show that reform has achieved good results, and aiming at the problems in the teaching practice we also put forward such improvement measures as strengthening the student-centered teaching method, promoting new teaching methods and optimizing curriculum assessment programs.

Objective To explore the role of team-based learning(TBL)in the teaching of pe-riodontics for undergraduates. Methods Totally 38 2008 grade undergraduates majored in stomatology were divided into six groups according to previous test scores. Individual test,group test and group re-sponder were conducted successively . Average test scores before and intra class were calculated and questionnaires survey was conducted after the course. Results There was no significant correlation be-tween average test scores intra class and basic knowledge and preview effect(r=0.028,P>0.05). Ques-tionnaire survey demonstrated that learning motivation,learning interests,knowledge mastering and com-munication ability of students were significantly improved. Conclusion TBL teaching promotes the class-room atmosphere and improves team collaboration and learning enthusiasm. Students show high accep-tance for this new teaching modes,so it can be tried in the teaching of stomatology.