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Ming-wen Fan

Publications and source records attributed to Ming-wen Fan.

At least 19 recordsLinked to original sources
PubMed2006

[A study of the physicochemical and biological properties of mutanase from Trichoderma harzianum].

OBJECTIVE: To determine the physicochemical properties of the mutanase of Trichoderma harzianum isolated from China and to study the influence of mutanase on the adherence of oral Streptococci and the structure of oral biofilms. METHODS: Six fungal strains belonging to Trichoderma were tested for mutanase production in the same cultural condition, the strain producing the highest mutanase activity was studied further and the pH and temperature optimum of the enzyme was determined. The RT-PCR method was used to obtain the gene coding for mutanase and the product was cloned to pMD18-T simple vector for sequencing. Inhibition effects of mutanase on the adherence of Streptococcus sobrinus OMZ176, Streptococcus sobrinus 6715, Streptococcus mutans MT8148 were studied by adherence test. The optical sectioning of biofilms with or without mutanase supplementation were analyzed by confocal laser scanning microscopy (CLSM). RESULTS: The highest enzymatic activity was achieved by Trichoderma harzianum Th1, the maximum activity was at pH 5.5 and at 40 degrees C. The nucleotide sequence was 92% homology with that of a known gene coding a mutanase (GenBank accession No. AJ243799). The adherence of Streptococcus sobrinus OMZ176, Streptococcus sobrinus 6715, Streptococcus mutans MT8148 was significantly inhibited by mutanase. Compared with control, the biofilms with mutanase supplementation had lower height and sparser structure. CONCLUSIONS: The mutanase from Trichoderma harzianum Th1 can inhibit the adherence of oral Streptococci and had an influence on the structure of oral biofilms.

Bacterial Adhesion↗
PubMed2006

[Construction of human bone morphogenetic protein-7 gene fluorescent eukaryotic cell expression vector and test of bioactivity in vitro].

OBJECTIVE: To construct fluorescent eukaryotic cell expression vector with human bone morphogenetic protein-7 (hBMP-7) gene and to transfect mouse stromal cell line W-20-17 to detect the bioactivity of pEGFP-hBMP-7 in vitro. METHODS: pEGFP-hBMP-7 plasmid was constructed by subcloning technique and identified by enzyme cutting and electrophoresis. W-20-17 cells were transfected with pEGFP-hBMP-7 by means of lipofectamine-2000 media methods. Transfection efficiency and gene expression were evaluated by fluorescent microscopy. ALP, von Kossa and osteocalcin (OC) were tested to determined the phenotypes of osteoblast. RESULTS: After 48 hours, the gene transfection efficiency was 40%. Based on GFP and immunofluorescence of pEGFP-hBMP-7, there was the expression of aim gene. After gene transfection, there were not significant different of cell morphology feature and cell proliferation. ALP activity, the number of calcium nodules and the expression of OC increased. CONCLUSIONS: pEGFP-hBMP-7 with bioactivity was constructed, which could induce W-20-17 cells to differentiate to osteoblasts.

Animals↗
PubMed2006

[Expression pattern and level of cytotoxic T lymphocyte-associated antigen-4 targeted anti-caries plasmids in eukaryotic cells].

OBJECTIVE: To investigate and compare the expression pattern and level of targeted anti-caries plasmids encoding different-size antigens in eukaryotic cells. METHODS: The A-P fragment of PAc (surface protein antigen) was removed from pGJA-P encoding the signal peptide, extracellular domains of human CTLA-4, human Ig hinge, CH2 and CH3 domains, A-P fragment of PAc and GLU (glucan binding domain) region of GTF-I of Streptococcus mutans, to obtain the plasmid pGJGLU. pCI vector skeleton of pGJA-P or pGJGLU was replaced by pVAX1 to construct plasmids pGJA-P/VAX and pGJGLU/VAX. CTLA4-Ig-GLU fragment was removed from pGJGLU and inserted into the vector pEGFP-N1 to obtain the recombinant plasmid pGJGLU/GFP. The CHO cells were transfected with those plasmids by using liposome and the expression of fusion protein was observed with fluorescence microscope. ELISA was used to detect the expression level of fusion proteins in cultured supernatants. RESULTS: Specific vesicles with green fluorescence could be observed in the CHO cells transfected with pGJGLU/GFP. The recombinant fusion protein could be detected in the cultured supernatants of CHO cells transfected with pGJA-P/VAX, pGJGLU/VAX and pGJGLU/GFP, of which the concentration was different. The highest concentration of recombinant fusion protein was observed in the supernatants of CHO cells transfected with pGJGLU/VAX. CONCLUSIONS: CTLA-4 targeted fusion protein could be expressed and secreted by eukaryotic cells. The size of antigen may affect the expression level of CTLA-4 targeted anti-caries DNA vaccine.

Animals↗
PubMed2006

[The study of salivary S-IgA antibody activity to clinical Streptococcus mutans in heat treated stress].

PURPOSE: The purpose of this study was to compare the salivary immunoglobulin A antibody response to Streptococcus mutans in normal with in heat treated stress. METHODS: Clinical Streptococcus mutans strains were isolated from 20 volunteers, serotyped by biochemical test and PCR, and genotyped by AP-PCR. Unstimulated secretions from submandibular glands and sublingual glands were collected from volunteers by modified collectors. Each identified genotype was cultured in two groups: control group was grown in BHI broth at 37 degrees C. for 3 hours; stress group was incubated in BHI broth at 42 degrees C. for 3 hours. Analysis of SIgA activity to clinical genotype strains and reference strains in different group was detected by Western blot. RESULTS: There was no significant difference between stress group and control group,in spite that some bands had strong or weak intensity. Different genotypes of S.mutans could have different immunoblotting profile as for an individual. SIgA from different volunteers could have different immonoblotting profiles as to the same genotype strain. CONCLUSIONS: Although Streptococcus mutans can express heat shock proteins in stress, this study suggests these new proteins have no significant effect on the reaction of SIgA to Streptococcus mutans. Different genotype strains may have different proteins, and different immunoreactivity to host. Different hosts may have different immunoreactivities to one genotypes of S.mutans.

Blotting, Western↗
PubMed2006

[Analysis on results of endodontic treatment and influencing factors].

OBJECTIVE: To assess the clinical outcome of root canal therapy (RCT) and the various factors that may influence the outcome of RCT. METHODS: A total of 695 teeth from 357 patients were retrospectively studied three years after endodontic treatment. Pre- and intra-operative information was collected from the original patient records. The post-operative sign or symptom, periapical status and coronal restoration integrity were examined 3 years after obturation. Data were subjected to bivariate and multivariate analysis. RESULTS: The cure rate for 695 teeth was 75.1%, 96.0% of which was considered to be functional. The tooth group, pre-operative pulp and periapical status, quality of root filling and integrity of coronal restoration were revealed by means of bivariate analysis to exert a significant influence on treatment outcome. The logistic analysis indicated that the odds for cure in the teeth with pre-operative periapical radiolucency, underfilling and "open" coronal restoration were significantly lower by 2 folds, 3 folds and 1.6 folds than their counterparts, respectively. CONCLUSIONS: The pre-operative periapical status, quality of root filling and the integrity of coronal restoration are main predictors of outcome in RCT.

Adult↗
PubMed2005

A new quantitative method using glucose for analysis of endodontic leakage.

OBJECTIVE: The purpose of this study was to introduce a new method for quantitative testing of endodontic leakage. STUDY DESIGN: Eighty straight maxillary anterior teeth were divided randomly into 3 experimental groups of 20 samples each and 2 control groups. The experimental groups were prepared using the modified double-flared technique and obturated by lateral compaction of cold gutta-percha with Pulp Canal Sealer EWT, Sealapex, or AH Plus sealer. With the leakage test device, coronal 1 mol/L glucose solution was forced under a hydrostatic pressure of 1.5 kPa toward the apical part of the root. Leakage was measured by the concentration of leaked glucose in apical reservoir at 1, 2, 4, 7, 10, 15, 20, and 30 days with the enzymatic glucose oxidase method. RESULTS: No significant difference of sealing ability was found among 3 test groups at 1, 2, 4, and 7 days. From the tenth day, Pulp Canal Sealer EWT showed the highest leakage, and the leakage was not significantly different between Sealapex and AH Plus. CONCLUSIONS: The quantitative method is sensitive, nondestructive, and clinically relevant. Pulp Canal Sealer EWT showed more leakage than Sealapex and AH Plus in most observation time.

Calcium Hydroxide↗
PubMed2005

[Effects of glucocorticoids on T helper cells balance in oral lichen planus].

OBJECTIVE: To investigate the effects of dexamethasone on Th1/Th2 cytokines in oral lichen planus. METHODS: Peripheral blood mononuclear cells (PBMC) were isolated by density gradient centrifugation from OLP patients and healthy controls. PBMC from patients with OLP were stimulated with phytohemagglutinin (PHA) and dexamethasone respectively for 72 h. The concentrations of interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) in culture supernatants were determined by ELISA. The mRNA levels for IFN-gamma and IL-4 in culture cells were evaluated using semi-quantitative reverse transcription-polymerase chain reaction. RESULTS: Compared with healthy controls, the levels of IFN-gamma in OLP patients were significantly lower (P < 0.05). The levels of IL-4 were higher, but not statistically significant (P > 0.05). The ratios of IFN-gamma/IL-4 were lower in patients with OLP (P < 0.05). Dexamethasone significantly inhibited the levels of IFN-gamma and IL-4 (P < 0.01). Moreover, IFN-gamma was inhibited significantly more than IL-4. The levels of IFN-gamma and IL-4 mRNA expression in culture cells were consistent with protein production in supernatants. CONCLUSIONS: Th2 immune response is predominant in OLP. Dexamethasone is an immunosuppressant inhibiting Th1/Th2 cytokines.

Adult↗
PubMed2005

[The study of salivary-SIgA reaction to Streptococcus mutans in acid environment].

OBJECTIVE: To test the salivary immunoglobulin A antibody activity to Streptococcus mutans in normal with in acid environment. METHODS: Streptococcus mutans strains were isolated from 20 volunteers, serotyped by biochemical test and PCR, and genotyped by AP-PCR. Unstimulated secretions from submandibular glands and sublingual glands were collected from volunteers by modified collectors. Each identified Streptococcus mutans genotype was cultured in two groups: control group was cultured in BHI broth pH7.2 at 37 degrees C for 2 h; acid shock group were cultured in TYEG broth (pH5.5) at 37 degrees C for 2 h. Analysis of SIgA activity to Streptococcus mutans genotypes in different groups was detected by Western blot. RESULTS: (1) The SIgA of each individual could response to his own Streptococcus mutans strains and the reference strains; (2) The same individual had different SIgA activity to different genotype strains; (3) There were no significant difference between acid groups and control groups, in spite that some bands had strong or weak intensity. CONCLUSIONS: Although Streptococcus mutans could express acid shock proteins in stress, the present study suggests that these new proteins have no qualitative effect on the reaction of SIgA to Streptococcus mutans.

Adult↗
PubMed2005

[Identification and isolation of human dental pulp stem cells].

OBJECTIVE: To isolate and cultivate human dental pulp stem cells (DPSCs). METHODS: Pulp tissue was removed from healthy young human teeth extracted for orthodontic purposes. The pulp was digested by Type I collagenase and dispase. Then single-cell suspensions were obtained by filter and cultivated. The clones were identified by expression of STRO-1. Under the conditions of inducement, clones were identified by activity of alkaline phosphatase (ALP), formation of mineralized nodule and expression of dentin sialoprotein (DSP), and by Oil Red-O dyeing and expressing of PPARr2. RESULTS: The clones had positive expression of STRO-1. When stimulated to differentiation, these cells took on dramatically high activity of ALP, had the ability of mineralization and expressed DSP. These cells also had ability to trans-differentiate into adipocytes. CONCLUSION: There are stem cells in human dental pulp tissues, which can be isolated and cultivated.

Adult↗
PubMed2005

[A clinicopathological study of 14 cases of oral granular cell tumor].

OBJECTIVE: To describe clinical and histological features of oral granular cell tumor (OGCT)and discuss their proliferative activity. METHODS: Clinical and microscopic features were assessed in 14 cases of OGCT collected from the department of oral pathology, college of stomatology of Wuhan University between 1970 and 2003. Immunohistochemical analysis was carried out using antibodies to S-100, NSE and Ki-67 and follow-up was obtained in all cases. RESULTS: Tongue was the most commonly affected location (13/14). The average age was 32.6 years (range 11 to 50). OGCT occurred more commonly in females (2.5:1). Histologically, the lesions consisted of polygonal cells with abundant, granular cytoplasm. Eleven cases had typical histological features, while 3 specimens were atypical. Growth patterns were expansive in 3/14 and invasive in 11/14, including 3 atypical cases. Immunohistochemical analysis disclosed that 100% of granular cells demonstrated moderated/strong staining for S-100 protein, neuron specific enolase (NSE). Nuclear immunostaining for Ki-67 was observed only in isolated granular cells. Seven patients with benign and two patients with atypical granular cell tumor had no recurrence and metastases. One patient with atypical granular cell tumor had local recurrence after 9 years and died of the disease 10 months later. CONCLUSIONS: OGCT cells display low proliferation activity. Most OGCTs are benign but few have malignant potential and periodic follow-up is mandatory to detect malignant transformation.

Adolescent↗
PubMed2005

[Gene expression of transcription regulator LMO 4 in tooth morphogenesis].

OBJECTIVE: To investigate the expression of transcription regulator LMO4 mRNA in the developing mouse molar and compare the expression pattern of LMO4 with that of Shh signaling molecule. METHODS: Wild-type embryos used in this study (E11.5-P1.5) were generated by mating Kun-Ming mice. The expression pattern of LMO4 during organ development was carried on by whole-mount in situ hybridization. The expression patterns of LMO4 and Shh mRNA during molar development were analysed by section in situ hybridization. Immunohistochemical staining of PCNA was carried on by SP method. RESULTS: LMO4 mRNA was widespread at early embryonic stages (E11.5) with positive hybridization signal in the mandibular reason, limb bud, brain, epidermis and somites revealed by whole-mount in situ hybridization. Section in situ hybridization showed that LMO4 was expressed in the tooth bud, the two tips of the enamel organ and the cervical loop from E13.5 to E16.5. While Shh was localized in the enamel knot on E14.5. On E18.5-P1.5, LMO4 transcripts were distributed in the ameloblast and the stratum intermedium. On E13.5-E16.5, the tooth bud cells and the cervical loop cells were PCNA positive. These were the same regions that showed LMO4 mRNA expression. CONCLUSIONS: LMO4 was confined to the dental epithelium and had spatial temporal expression patterns during tooth morphogenesis. The expression patterns of LMO4 and Shh were similar. In early tooth development, LMO4 might regulate cell proliferation. In late tooth development, it might participate in the ameloblast differentiation.

Adaptor Proteins, Signal Transducing↗