1.Protein levels and its clinical significance of septin-9 and clusterin in peripheral blood of epithelial ovarian cancer patients
Nenan LYU ; Hongwen YAO ; Ting XIAO ; Yanning GAO ; Lingying WU
Chinese Journal of Obstetrics and Gynecology 2015;(9):679-684
Objective To evaluate septin-9 and clusterin protein levels in the peripheral blood samples from epithelial ovarian cancer patients, and explore its clinical significance. Methods Clinical data of 200 patients in Cancer Hospital,Chinese Academy of Medical Sciences from Jan. 29, 2008 to Feb. 1,2010 were collected. The peripheral blood samples were obtained from 137 epithelial ovarian cancer patients, 12 borderline ovarian tumor patients, 10 benign ovarian tumor patients, 41 benign pelvic lesion patients and 58 healthy women. The septin-9 and clusterin protein levels in the plasma were measured by double antibody sandwich ELISA or ELISA. The clinical significance of clusterin and septin-9 in plasma was analyzed. The diagnostic efficacy of septin-9 and clusterin protein in the detection of ovarian cancer was evaluated by the area under the curve (AUC) of the receiver operating characteristic (ROC) curve. Results Double antibody sandwich ELISA showed: the mean levels of plasma septin-9 in epithelial ovarian cancer patients or benign pelvic lesion patients were significantly higher than that in healthy women detedted by double antibody sandwich ELISA (P<0.01). The mean levels of plasma septin-9 in epithelial ovarian carcinoma patients with tumor family history or distance metastasis were significantly higher than those patients without (P<0.05). While the expression level of septin-9 protein in peripheral blood of ovarian cancer patients was not related to the patient age, pathologic stage, pathologic differentiation, smoking history, treatment history (including surgery, radiotherapy and chemotherapy) and lymph node metastasis (all P>0.05). ELISA showed: the mean level of plasma clusterin in epithelial ovarian cancer patients was significantly higher than that in healthy women deteded by ELISA (P=0.021). The expression level of clusterin protein in peripheral blood of ovarian cancer patients was not related to the above clinical pathological parameters (all P>0.05). To distinguish between ovarian cancer patients and healthy women by septin-9 protein expression level in plasma, when AUC was 0.712 and cut off was 0.28, the sensitivity of detection ovarian cancer by septin-9 protein expression was 82.5%, and the specificity was 50.0%. To distinguish between ovarian cancer patients and healthy women by clusterin protein expression level in plasma, when AUC was 0.636 and cut off was 87.96 pg/L, the sensitivity of detection ovarian cancer by clusterin protein expression was 71.5%, and the specificity was 41.4%. Conclusions The expression of septin-9 and clusterin protein in peripheral blood of ovarian cancer patients is increased, especially the expression level of septin-9 protein with related to the distant metastasis. The study results shown that the detection of septin-9 and clusterin in plasma has a certain diagnosis value in ovarian cancer, which may be a potential markers for ovarian cancer.
2.Identification and virulence analysis of a Streptococcus suis strain isolated from human blood
Yanning LYU ; Jie LI ; Yiwei DU ; Xinyu LI ; Quanyi WANG ; Lijuan CHEN
Chinese Journal of Zoonoses 2017;33(7):599-603
To identify and analyze the virulence of a bacteria strain isolated from the blood of a patient with suspected Streptococcus suis (S.suis) infection in a hospital of Beijing,we inoculated the bacteria strain isolated from the blood of the patient to the Columbia with sheep blood agar plate,after Gram staining and microscopical examination,serum agglutination test,VITEK 2 Compact microbial identification system test and matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) test,S,suis species specific gene 16SrRNA,S.suis species serotype 2 specific virulence gene capsule polysaccharide 2J (cps2J) and virulence gene muramidase-released protein (mrp),hemolysin (sly),extracellular factor protein (ef),glutamate dehydrogenase (gdh) genes,fibronectin-binding protein (fbps),glyceraldehyde-3-phosphate dehydrogenase (gapdh) genes and virulence correlated gene orf2 were further detected by PCR.Results showed that the suspicious bacteria strain of S.suis was identified as S.suis type 2 (S.suis 2) by conventional methods,MALDI-TOF-MS and PCR.PCR results showed that cps2J,sly,ef,gdh,fbps,gapdh and or f2 genes were positive,and mrp gene was negative.In conclusion,the bacteria strain isolated from the patient's blood is sly+/ef+/mrp-virulent S.suis 2.
3.Diagnosis of common blood stream infection pathogens based on central homo-sequence primer by multiplex PCR combined with MALDI-TOF MS
Yue CHANG ; Yu WANG ; Yanning MA ; Jiyong YANG ; Chengbin WANG ; Jianxin LYU
Chinese Journal of Laboratory Medicine 2021;44(5):413-420
Objective:Based on the high-throughput detection technique of multiplex PCR combined with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, constructing the characteristic SNP profiles of different strains, and establishing a rapid, accurate and highly sensitive method for the diagnosis of bloodstream infection pathogens.Methods:Seven kinds of pathogens such as common Escherichia coli were selected as target. The multiple PCR reaction conditions was optimized, and the characteristic peaks of each target bacteria were detected by MALDI-TOF MS to establish the joint detect system. Common primer pairs and central homo-sequence primer pairs were designed to analyse the formation of primer dimer. Using simulated bacterial infection blood samples with detection system to determine specificity and sensitivity. One hundred and fifty blood samples from suspected bacteremia patients were collected from June to September 2020 in a hospital in Beijing, and the identification results were compared to traditional identification method of clinical application that are using χ 2 test. Results:The cycle threshold (Ct) value of the central homo-sequence primers that were designed were more than 38, with a delay of 6-10 cycles. The joint mass spectrometry detection system could detect seven kinds of bacteria divided into two groups at the same time. The target bacteria can be detected specific product of the peak, and the clinical strains other than the target strains only had primer peaks. All maps had non-specific miscellaneous peaks. The sensitivity of Escherichia coli could reach 50 CFU/ml, and the detection limit of other bacteria was 100 CFU/ml. The detection results of 150 patients showed that 46 cases were positive by traditional method. The positive rate was 30.67% (46/150), including two cases of mixed infection. Forty-eight cases were positive by mass spectrometry, and the positive rate was 32.0% (48/150), including three cases of mixed infections. The negative coincidence rate was 100% (101/101). The comparison of the two methods showed that the P=0.625>0.01, the Kappa=0.938, the sensitivity and specificity was 97.82%(45/46) and 97.11%(101/104), respectively. There was no significant difference between the two methods, and the results of nucleic acid mass spectrometry could also be used in clinic. Conclusions:The established detection system can not only quickly and accurately detect seven common pathogens causing bloodstream infection, and effectively shorten the time needed for traditional culture and identification, but also can detect multiple bacterial mixed infections at the same time to make up for the possibility of missed detection. Besides, the method can also be used to identify other bacteria.