The Study Of Periodontal Pathogens LPS On The Gene Expression Patterns In PDLCs And The Specific Detection And Treatment Of Periodontal Mocrobiota

1. Periodontal ligament cells( PDLCs) are the predominant element of periodontium and play a central role in the normal turnover, regeneration and repair following injury to periodontiurn. Periodontal pathogen can inhibit the growth of PDLCs and affect the normal function of cells. It is very important to analyze the gene expression patterns in PDLCs stimulated by periodontal pathogen LI扴 by DNA Chip to study the pathogenesis mechanism and to find the prevention and treatment measurement. By applying DNA Chip we analyzed the gene expression patterns in PDLCs stimulated by Pi LPS. we identified 14 differentially expressed genes. including 6 upregulated and 8 downregulated genes, most of the genes upregulated were involved in protein kinase and protein phosphatase, while downregulated genes were related to signal transduction and transcription. apoptosis related gene receptor gene. We employed in situ hybridization method to observe the expression of lAP- 2 in PDLCs. The results showed that PDLCs were IAP-2 positive before stimulation by Pi LPS and IAP-2 negative after stimulation by Pi LPS. The result showed that Pi LPS could inhibit the IAP-2 expression of PDLCs and induce apoptosis in PDLCs. 2. The periodontal diseases are now accepted as being site-specific, requiring the development of more rapid, accurate diagnostic tests and site-specific therapy based on the diagnosis of periodontal disease activity. The aim of the present study was to evaluate the diagnostic value of oligonucleotide DNA probe and 5 Periocheck chair-side examination for periodontal pathogens and detect the prevalence of specific periodontal pathogens in subgingival plaque. A) Oligonucleotide DNA probes analysis showed the positive detection frequency rates of Pg. Bf and Td in patients were 86.67%, 85% and 96.67% respectively, Aa was detected in 31.67% diseased sites. Pg.. Bf and Td were found to be prominent periodontopathic bacteria and their presence in subgingival pocket can lead to development of periodontal disease. Pg.. Bf and Td were found to be related with each other, maybe existed in microbial complexes in subgingival plaque and coaggretate together. B) Peptidase activity in subgingival plaque by Periocheck test was significantly correlated with clinical parameters. peptidase activity in periodontitis sites was higher than that of healthy control sites. The result suggested peptidase activity detected by Periocheck test had a good sensitivity and specificity. could be used to differentiate active and inactive periodontal diseased sites. C) Peptidase activity in subgingival plaque by Periocheck test was significantly correlated with Pg.. Bf and Td detected by oligonucleotide DNA probes. the results implied that peptidase activity could indicate the infection of Pg.. Bf andTd. D) Peptidase activity in subgingival plaque was found to positively associated with GCF-AST, GCF-ALP level, the relationship demonstrated specific bacteria were involved in the progression of periodontitis. because the peptidase activity was derived from Pg, Bf and Td, GCF-AST level could be used as a marker of tissue destruction and GCF-ALP level might be used as a marker of gingival inflammation. E) To evaluate the diagnostic value of oligonucleotide DNA probe and...