The Experimental Study On The Homology Of The Helicobacter Pylori In Oral Cavity And That In Stomach

Objective: To compare the DNA sequences of the 16 S rDNA regions of the Helicobacter pylori in oral cavity and stomach by NCBI blast and DNAMAN. To clarify the homology of H. Pylori in oral cavity and that in stomach,For testing the Helicobacter pylori may be transmitted by gastro-oral rout in the population. Methods:1. Collecting the gastric mucosa specimens from the patients, Who suffered from chronic gastritis or gastric ulcer, duodenal ulcer comfored by gastroscopy, meanwhile the subgingival plaque samples were taken from the first and the second molar areas with a sterile curette and gargle 2-3ml. 2. Culture, isolate and identify the Helicobacter pylori strains from the gastric mucous tissue 、subgingival plague and gargle. Extracting the genome DNA of Helicobacter pylori and to do 16 S rDNA amplification by PCR. 3. The DNA ware recovered and sequenced then to analyse the sequences by BLAST NCBI and DNAMAN. Results:1. Gastric mucosa and subgingival plaque, gargle clinical specimens were collected from 69 patients in this experiment. The positive rate of various specimens of rapid urease test were 62%, 72%, 43% respectively.The difference was statistically significant( p<0.05). 2.In this experiment, the micro aerobic environment of the growth of Helicobacter pylori was created by using airtight glass culture jar. The rapid urease test positive specimens were cultured,Gastric mucosa, subgingival plaque, gargle samples positive rate of the Clinical strains of Helicobacter pylori through cultures were 60%, 30% and 36%, respectively.The difference was statisitically significant( p<0.05).The characterized colonies of the Helicobacter pylori were found in the solid culture medium. Methods rapid urease test、oxidase test and catalase test were applied to detect Helicobacter pylori,the 3.results of three detection methods were positive. 3 Clear target bands ware appeared in the electrophoresis map of the PCR reaction amplification products,and the PCR reaction was used to further verify the purpose of the bacterial strain was Helicobacter pylori. 4 The sequences ware compared and analyzed by NCBI BLAST and DNAMAN, Which showed 93.45%-99% homology of the 16 S rDNA regions sequences of Helicobacter pylori from the oral cavity(subgingival plaque and gargle) and gastric in the same patient, and showed differences of 3-35 bases. Conclusion: The sequences of the 16 S rDNA regions of the Helicobacter pylori in the oral and stomach have higher homology.