AIM:To explore whether miR-21 low expression enhances the effect of matrine ( MAT) on the ap-optosis of hepatocellular carcinoma cells .METHODS:Real-time fluorescence quantitative PCR ( RT-qPCR) was used to detect the expression of miR-21 in the HepG2 cells treated with different concentrations of MAT .The effect of miR-21 on MAT-induced HepG2 cell apoptosis was analyzed by flow cytometry .The mRNA and protein expression of Bcl-2 and Bax in the HepG2 cells treated with MAT was determined by RT-qPCR and Western blot .RESULTS:The expression of miR-21 increased with the increasing concentration of MAT .Low expression of miR-21 promoted MAT-induced apoptosis , and en-hanced the expression of Bax at mRNA and protein levels ( P<0.05 ) , while inhibited the expression of Bcl-2 at mRNA and protein levels (P<0.05).CONCLUSION:Low expression of miR-21 enhances MAT-induced HepG2 cell apoptosis by inhibiting the expression of Bcl-2 and promoting Bax expression .

Abstract: Objective To explore the prevalence and bacterial strains of Francisella tularensis (F. tularensis) in wild rodents in Changbai Mountain area of China, and to further understand the epidemiological characteristics of F. tularensis infections in this area. Methods Wild rodents were captured from forest and forest-edge farmland from Kuandian County and Jianshi Forest District in the Changbai Mountain area, 2012-2014. DNA was extracted from the spleen tissues of the rodents, and the fopA gene of F. tularensis in wild rodents was detected using nested PCR. The infection rates were calculated for different areas and rat species. The bacterial subspecies of positive samples were identified using type-specific primers (C1/C4), and sequencing and comparative analysis were performed. Results A total of 133 wild rodents belonging to 6 rat species were captured. Among them, eight samples from three rat species (Apodemus agrarius, Apodemus peninsulae, Tscherskia triton ) were detected positive, with the overall positive rate of 6.01%. The positive rates of F. tularensis of Ji'an and Kuandian were 7.46% and 4.54%, respectively, and there was no difference in positive rates for different regions (χ2=0.117, P=0.732) and different rat species (χ2=0.641, P=0.986). The subspecies analysis showed that the detected 8 trains of F.tularensisall belonged to F.tularensis type B (F.subspecies subsp. holarctica). Genetic evolution analysis was performed on the fopA gene sequences of three positive samples (JA56, JA33, and JA38), which clustered together with Russia strains(CP009694.1, CP044004.1) and China strains (HM371344.1, HM371343.1) F.tularensis type B, with sequence similarities ranging from 99.21% to 99.47%. Conclusions Infection of F.tularensis subsp. holarctica existed in wild rodents in Changbai Mountain area of China, which suggests the existence of F.tularensis infection risks in this area.

Objective To detect the content of plasma ctDNA and the mutation rate of BRAF V600E in plasma of patients with thyroid carcinoma ,and to explore its clinical significance. Methods Plasma ctDNA was extracted from 16 patients with thyroid carcinoma and 59 patients with benign thyroid nodules by using the blood genomic DNA Extraction Kit. The ctDNA content was detected by fluorescence quantitative PCR ,and the mutation of circulating BRAF V600E was detected by PCR and sequencing. Then the clinical significance was analyzed by combined detection analysis. Results The content of ctDNA in thyroid cancer group was significantly higher than that in benign nodule group (P < 0.01). BRAF V600E mutation detection showed that the mutation rate was 43.75%,but benign nodules had no mutation. Parallel combined detection improved the sensitivity and the specific-ity of the combined detection was higher. Conclusion Combined detection of ctDNA and BRAF V600E in plasma is helpful for differential diagnosis of benign and malignant thyroid nodules.

Objective To explore the microRNA-16 (miR-16) and nuclear-transcription factor-κB1 (NF-κB1) expressions in human brain gliomas and their correlations with cell invasion and growth of malignant gliomas SHG44,U87 and U373.Methods (1) Twenty-nine cases of human glioma tissue samples and 6 normal brain tissues,collected in our hospital from January 2000 to January 2011,were chosen in our study; quantitative real-time polymerase chain reaction (qRT-PCR) was used to determine the expressions ofmiR-16 and NF-κB1 in these tissues.(2) In vitro cultured U87,U373 and SHG44 cells were divided into blank-control group,nonsense sequence transfected group and miR-16 mimics transfected group; 48 h after the transfection,qRT-PCR was used to detect the expressions of miR-16 and NF-κB1; tmnswell assay was used to observe the cell invasion capability; 72 h after the transfection,Western blotting was employed to detect the protein expressions of NF-κB1,matrix metallopeptidase 9 (MMP-9) and MMP-2.(3) Luciferase reporter assay was used to detect the target regulating role of miR-16 in NF-κB1 gene.(4) U87 cells were used as negative control group,and U87 cells carried stably expressed miR-16 gene were implanted into intracranial and subcutaneous nude mice (U87-miR-16 group); immunofluorescence was used to detect the MMP-9 expression,and immunohistochemical staining was used to detect the protein expressions of Ki-67,NF-κ B1 and MMP-9; subcutaneous tumor volume was measured and the growth curve was drawn.Results (1) The qPCR results showed that the expression of miR-16 in human brain glioma tissues was significantly lower than that in normal brain tissues; and gradually decreased miR-16 expressions were noted in gliomas of graded Ⅰ,Ⅱ,Ⅲ and Ⅳ (P＜0.05); NF-κB1 expression in human brain glioma tissues was significantly higher than that in normal brain tissues; and gradually increased NF-κB1 expressions were noted in gliomas of graded Ⅰ,Ⅱ,Ⅲ and Ⅳ (P＜0.05).(2) As compared with those in the blank-control group and nonsense sequence transfected group,miR-16 mimics transfected group had significantly increased miR-16 expression,decreased NF-κB1 mRNA expression,decreased invasiveness,and decreased protein expressions of NF-κB1 and MMP-9 (P＜0.05).(3) Luciferase reporter assay showed that the fluorescence normalized ratio in the pMIR-NF-κB1 group was signfcaintly higher than that in the pMIR-NF-κB1+pre-miR-16 group (P＜0.05).(4) As compared with the negative control group,the U87-miR-16 group on the 24-42 d of implantation had significantly smaller volume of tumors (P＜0.05),and lower MMP9 expression,and NF-κB1,MMP-9 and Ki-67 expressions (the proliferation index of Ki-67:13.91％ and 32.98％).Conclusion MiR-16 inhibits glioma cell invasion and growth through down-mgulating NF-κB1 and MMP-9 expressions.