Objective Streptococcus sanguis is a possible candidate bacterium for the caries replacement therapy, which has no advantages in the acidic environment.The aim of the study was to construct acid-resistant strains of Streptococcus sanguis, determine its acid tolerance, and explore the mechanism of its antagonism against Sterptococcus mutans.Methods By gradually reducing the pH value of the medium, we constructed acid-resistant strains of Streptococcus sanguis, observed their growth and measured their acid tolerance according to their survival rate against lethal pH.We evaluated the competitive relationship between Streptococcus sanguis and Streptococcus mutans by plate experiment and detected the changes of related acid resistance genes by real-time quantitative PCR.Results The growth of Streptococcus sanguis and its acid-resistant strains were limited by the pH value, and that of Streptococcus sanguis was better in either acidic or normal environment.The lethal pH value of Streptococcus sanguis was 3.6, that of its acid-resistant strains was 2.3, and the survival rate of the acid-resistant strains was 66.59% in the pH 3.6 environment.In comparison, the lethal pH value of Streptococcus mutans was 2.5, that of its acid-resistant strains was 2.1, and the survival rate of the acid-resistant strains was 2.55% in the pH 2.5 environment.In the presence of chloramphenicol, the acid-resistant strains could not survive in the original lethal pH.In the sub-lethal pH environment, the expressions of the acid resistance-related genes Groel and Dnak in the acid-resistant strains were significantly up-regulated as compared with those in the original Streptococcus sanguis (P<0.05).Conclusion Streptococcus sanguis has an acid adaptability and can enhance acid resistance in the sub-lethal pH environment.Acid-resistant Streptococcus sanguis in the replacement therapy may provide some new ideas for the treatment of dental caries.

Objective To explore the efficiency and safety of trans-sheath intraluminal forceps biopsy under digital subtraction angiography(DSA)guidance for assisting diagnosis of pulmonary artery obstructive diseases.Methods Data of 16 patients who underwent trans-sheath intraluminal forceps biopsy for pulmonary artery obstructive diseases were retrospectively analyzed,and the clinical manifestations were recorded.The technical success of biopsy was defined as tissue obtained met the needs of pathology diagnosis.For patients with malignant pathology results,the final diagnosis was malignant,for those with benign pathology results after biopsy and no obvious changes after 6-month or longer follow-up,or benign pathology results after surgical resection,the final diagnosis was benign,otherwise was no clear diagnosis.The operation time,technical success rate,diagnostic efficiency,complications and changes of pulmonary artery pressure before and after the biopsy were observed.Results Among 16 patients,9 complained of intermittent chest tightness,4 complained of chest pain with chest tightness,2 complained of chest pain but 1 denied any symptoms.The lesions located in the left lung in 10 cases and in the right lung in 6 cases,all with enhanced CT showed filling defects of the involved branch of pulmonary artery.Totally 16 trans-sheath intraluminal forceps biopsies were performed in 16 patients,with an average operation time of(31.02±6.02)min and technical success rate of 100%.Malignant tumors were finally diagnosed in 10 cases,including 1 case of lung cancer with false-negative biopsy result,while biopsy correctly diagnosed benign lesions in the other 6 cases.Transient worsening chest pain with chest tightness occurred in 2 cases and relieved after symptomatic treatments.No statistically significant difference of pulmonary artery pressure was found before([53.38±14.28]mmHg)and after([53.69±14.15]mmHg)biopsy(P＞0.05).Conclusion DSA-guided trans-sheath intraluminal forceps biopsy was relatively safe and valuable for assisting diagnosis of pulmonary artery obstructive diseases.

Objective To observe the feasibility and effectiveness of fluoroscopy-guided Fustar adjustable bent sheath clamp biopsy for diagnosing obstructive esophageal diseases.Methods Totally 29 patients with esophageal or esophagogastric junction obstruction who failed to complete endoscopic biopsy were retrospectively analyzed.Real-time fluoroscopy-guided clamp biopsy of lesion areas were performed through 10F Fustar adjustable bent sheath under local anesthesia.The technical success rate,operation time,radiation dose were recorded,and the complications were evaluated.Results Clamp biopsy of lesion areas were successfully performed in all 29 cases,with technical success rate of 100%(29/29),the average operation time of(29.81±10.05)min and the average radiation dose of(127.14±100.36)mGy.No serious complication such as esophageal perforation nor massive bleeding occurred.After biopsy,22 cases(22/29,75.86%)were preliminarily diagnosed as positive,among them 2 cases underwent surgical operation,and the postoperative pathological results were consistent with biopsy.Negative biopsy results were found in 7 cases(7/29,24.14%),among them 2 cases underwent clamp biopsy again 3 months later which showed positive results.Conclusion Fustar adjustable bent sheath clamp biopsy was feasible and effective for diagnosing obstructive esophageal diseases,which could be regarded as the substitution and supplementation of endoscopic clamp biopsy.

Objective: To investigate the difference in invasiveness between vulvovaginal candidiasis(VVC) and recurrent vulvovaginal candidiasis(RVVC) strains, and to explore the effect of strains with different secreted aspartate protease(Sap) on vaginal local immunity. Methods: Vaginal secretions of VVC and RVVC patients were collected for fungus identification.Candida albicans(C.albicans) were taken for drug sensitivity analysis, 25 S rDNA genotyping, and detection of secreted aspartate protease(Sap) and phospholipase(Plb) activity.C.albicanswith different Sap activity were cultured with vaginal epithelial cells, and the levels of Interleukin(IL)-4, IL-8, IL-17 in cell supernatant were measured by ELISA. Results: Sap activity of VVCC.albicanswas stronger than that of RVVC. After infection withC.albicans, the secretion of IL-4, IL-8 and IL-17 by vaginal epithelial cells was higher, and IL-8 and IL-17 appeared earlier and lasted longer.C.albicanswith strong Sap enzyme activity could stimulate vaginal epithelial cells to secrete more cytokines. Conclusion Except for the Sap activity, there was no significant difference in the invasiveness between VVC and RVVC strains.C.albicanscould activate the vaginal host immune response in a short time. The lower Sap activity ofC.albicansin RVVC patients may be related to the protective factors secreted by the vaginal epithelium.

Transient receptor potential vanilloid-1(TRPV1) channel is a non-selective ligand-gated cationic channel with multiple activation mechanisms in the transient receptor potential subfamily. In recent years, a large number of studies have found that TRPV1 plays an important role in the field of cardiovascular diseases such as hypertension and atherosclerosis. With the in-depth study of traditional Chinese medicine, it has been found that Chinese medicine monomers and their active components can activate or inhibit TRPV1 channels, which has certain potential in the study of cardiovascular diseases. In this paper, the role of TRPV1 channel in cardiovascular diseases and the research progress of traditional Chinese medicine prevention and treatment of cardiovascular diseases based on TRPV1 channel are reviewed, in order to provide new ideas for prevention and treatment of cardiovascular system diseases.