Research progress on the detection methods of Zika virus / 医学研究生学报

Zika virus (ZIKV), a kind of mosquito borne flavivirus , has spread rapidly in recent years and triggers global large scale epidemic outbreaks.ZIKV infection can lead to severe potential complications such as infant microcephaly and Guillain Barrésyndrome, which has caused social panic and global widespread attentions .The serological detection of ZIKV is easy to be con -fused by other flaviviruses, thus the establishment of specific and effective detection methods is extremely important in the prevention and control of ZIKV transmission.In this paper, the epidemic situation of ZIKV in global and Chinese and research progress of ZIKV detection methods including pathogeny detecting method , serological detecting method and nucleic acid detecting method are reviewed , and the future perspective of detection methods research is also briefly described .

Application Value of Plasma Lipoprotein-associated Phospholipase A2 Level and AT- Ⅲ Activity on Risk Stratification and Nearby Risk Assessment in Patients With Non-ST Segment Elevation Acute Coronary Syndrome / 中国循环杂志

Objective: To explore the relationship between lipoprotein-associated phospholipase A2 (Lp-PLA2) level, antithrombinⅢ (AT-Ⅲ ) activity and global registry of acute coronary events (GRACE) score in patients with non-ST segment elevation acute coronary syndrome (NSTE-ACS); to analyze the predictive value of Lp-PLA2, AT- Ⅲ on risk stratification and nearby risk assessment in NSTE-ACS patients. Methods: Our research included in 2 groups: NSTE-ACS group, n=260 patients with confirmed diagnosis and regular treatment; Control group, n=50 in-hospital patients with coronary angiography excluded coronary artery disease (CAD).plasma level of Lp-PLA2 and AT-Ⅲ activity were examined in the next morning of admission. GRACE score was calculated in NSTE-ACS patients and based on GRACE score, NSTE-ACS group was further divided into 3 subgroups as Low risk subgroup, GRACE score≤108, n=121, Middle risk subgroup, GRACE score (109-140), n=73 and High risk subgroup, GRACE score>140, n=66. The relationships between Lp-PLA2 level, AT-Ⅲ activity and GRACE score were evaluated and the occurrence of major adverse cardiovascular events (MACE) was recorded within 3 months of discharge. Results: ① Compared with Control group, NSTE-ACS group had increased Lp-PLA2 level, P<0.05 and decreased AT-Ⅲ activity, P<0.01. ② In NSTE-ACS group, Lp-PLA2 levels were elevating from Low risk subgroup to Middle risk subgroup and to High risk subgroup accordingly, all P<0.01; compared with Low risk and Middle risk subgroups, High risk subgroup showed decreased AT-Ⅲ activity, P<0.01 and P<0.05; while AT-Ⅲ activity was similar between Low risk and Middle risk subgroups, P>0.05. ③Partial correlation analysis presented that GRACE score was positively related to Lp-PLA2 (r=0.641, P=0.000) and negatively related AT-III (r=-0.179, P=0.006). ④ The area under ROC curve for MACE occurrence in GRACE score was 0.811, in Lp-PLA2 was 0.862 and in AT- Ⅲ was 0.631, all P<0.01; multivariate Logistic regression analysis indicated that Lp-PLA2, GRACE score and HDL-C were the independent predictors for nearby MACE occurrence in NSTE-ACS patients. Conclusion: Blood Lp-PLA2 level and AT-Ⅲ activity were important for risk stratification in NSTE-ACS patients;AT- Ⅲ had less value than Lp-PLA2 and GRACE score for nearby risk assessment.

Effect of DOT1L gene silence on proliferation of acute monocytic leukemia cell line THP-1 / 中国实验血液学杂志

This study was aimed to investigate the influence of short hairpin RNA (shRNA) on proliferation of human leukemia cell line THP-1. The shRNA targeting the site 732-752 of DOT1L mRNA was designed and chemically synthesized, then a single-vector lentiviral, tet-inducible shRNA-DOT1L system (Plko-Tet-On) was generated. Thereafter, the THP-1 cells with lentivirus were infected to create stable cell line with regulatable shRNA expression. The expression of DOT1L in the THP-1 cell line was assayed by RT-PCR. Effect of shRNA-DOT1L on the proliferation of THP-1 cells was detected with MTT method,and the change of colony forming potential of THP-1 cells was analyzed by colony forming unit test. Cell cycle distribution was tested by flow cytometry. The results indicated that the expression of DOT1L was statistically lower than that in the control groups. The proliferation and colony forming capacity of THP-1 cells were significantly inhibited. The percentage of cells at G0/G1 phase increased in THP-1/shRNA cells treated with Dox while the percentage of cells at S phase significantly decreased as compared with that in the control group. It is concluded that the shRNA targeting DOT1L can effectively inhibit the proliferation of acute monocytic leukemia cell line THP-1.

Early apoptosis of HL-60 cells induced by anti-CD44 McAb A3D8 inhibiting ERK1/2-upregulated Bim expression / 中国实验血液学杂志

This study was aimed to investigate the effects of anti-CD44 mAb A3D8 on proliferation and apoptosis of AML cells, to explore the mechanism of ERK1/2 and Bim in this process. Effect of the anti-CD44 mAb A3D8 on the HL-60 cell proliferation was assayed with MTT method, the change of mitochondrial transmembrane potential of HL-60 cells was analyzed by flow cytometry. The mRNA expression of Bim was determined by real-time quantitative RT-PCR. Western blot was used to detect the protein expression of p-ERK1/2. The results showed that mAb A3D8 could remarkably inhibit the proliferation capacity of the HL-60 cells in a dosage- and time-dependent ways. The mitochondrial transmembrane potential in HL-60 cells treated with A3D8 (3.0 µg/ml) was significantly decreased as compared with the control cells. Furthermore, the mRNA expression of Bim was much higher than that in controls. Expression of the p-ERK was much lower than that of the controls. It is concluded that anti-CD44 mAb A3D8 can inhibit the proliferation and induce the apoptosis of HL-60 cells, mechanism of which is enhancing the expression of Bim via inhibiting p-ERK1/2.

Inhibition of NHE1 promotes hypoxia-induced differentiation of K562 leukemic cells / 中国实验血液学杂志

This study was purposed to investigate the effect of hypoxia microenvironment on K562 leukemic cell differentiation, and characteristics of NHE1 involvement in this process. The K562 cells were treated with hypoxia-mimical agent CoCl₂ or under actual hypoxia culture, and the specific NHE1 inhibitor Cariporide was used to inhibit NHE1 activity. The fluorescent probe BCECF was used for pH(i) measurements. Gene expression was analyzed by RT-PCR. The morphological characteristics was determined by Wright's staining. Signaling pathways were detected by Western blot using phosphospecific antibodies. The results indicated that the hypoxia or mimetic hypoxia favored K562 cells differentiation with up-regulation of C/EBPα. Moreover, treatment with Cariporide under hypoxia synergistically enhanced leukemia cell differentiation. Treatment with Cariporide increased levels of phosphorylated ERK5 and P38 mitogen-activated protein kinase (MAPK). It is concluded that the hypoxia or mimetic hypoxia can induce the differentiation of K562 cells, the inhibition of NHE1 activity can promote the hypoxia-induced K562 cell differentiation. The enhancement of hypoxia-induced K562 differentiation by Cariporide via MAPK signal pathway suggests a possible therapeutic target of NHE1 under hypoxia microenvironment in the treatment of leukemias.

Reversal of multidrug resistance in HL-60, MSC and CD34(+) cells from umbilical cord blood by sustained intracellular acidification / 中国实验血液学杂志

The aim of this study was to investigate the effect of intracellular acidification on accumulation of rhodamine 123 (rh123) in non-mature cells with none or low expression of multidrug resistance MDR1. The expression of MDR1 mRNA was detected by real-time quantitative RT-PCR. Confocal laser microscopy was used to determine the calibration curve of intracellular acidification (pHi). MTT assay was used to detect the cytotoxicity of intracellular acidification on HL-60, MSC and CD34(+) cells from umbilical cord blood. Flow cytometry was applied to measure the influence of intracellular acidification. The results indicated that the intracellular acidification had no obvious cytotoxicity on HL-60, MSC and CD34(+) cells. The acidification resulted in the increased rhodamine 123 accumulation in HL-60, MSC and CD34(+) cells without P-gp activity. Moreover, the more primitive cells, the less accumulation of intracellular Rh123 were observed. It is concluded that the intracellular acidification can reverse the MDR of HL-60, MSC and CD34(+) cells.

Na(+)/H(+) exchanger 1 expression and its effect on apoptosis in K562 and HL-60 cells with DNA damage / 中国实验血液学杂志

This study was aimed to investigate the expression of Na(+)/H(+) exchanger 1 (NHE1) in K562 and HL-60 cells undergoing DNA damage induced by etoposide and to elucidate the regulating mechanism. Real-time quantitative PCR (RQ-PCR) and Western blot methods were used to determine the expression of NHE1 in K562 cells after the treating with etoposide. Meanwhile, the flow cytometry was used to detect the apoptosis of leukemic cells. The luciferase reporter vector containing NHE1 promoter was constructed to measure relative luciferase activity after treating with different etoposide concentrations. The results showed that the mRNA and protein of NHE1 increased in accordance with apoptosis ratio in HL-60 cells after treated with etoposide (p < 0.05), but no such obvious increase in K562 cells. Treatment with NHE1 specific inhibitor could block etoposide induced alkalization and reduce the apoptosis ratio of HL-60 cells. The expression pattern and apoptosis alteration was not similar in K562 cells. Relative luciferase activity of reporter vector containing NHE1 promoter however increased in K562 cells after treated with etoposide. It is concluded that the expression of NHE1 is up-regulated in the process of apoptosis of HL-60 cells induced by etoposide and depends on the pHi increasing caused by NHE1 up-regulation which is not found in K562 cells although the transcriptional activity increased.

Role of Na(+)/H(+) exchanger 1 in apoptosis of HL-60 cells induced by etoposide and its mechanism / 中国实验血液学杂志

This study was aimed to investigate the role of Na(+)/H(+) exchanger 1 (NHE1) in apoptosis of HL-60 cells induced by etoposide. Real-time quantitative PCR (RQ-PCR) and Western blot methods were used to determine the expression of NHE1 in HL-60 cells after the treatment with etoposide. Meanwhile, laser scanning confocal microscopy was used to test the intracellular pH (pHi) of HL-60 cells. Cell apoptosis was measured by DNA fragmentation and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay. The results showed that etoposide induced cell apoptosis after treatment for 24 hours. The expression level of NHE1 mRNA increased by 2.848 +/- 0.886 times after treatment with etoposide for 12 hours (p < 0.01), and the expression of NHE1 protein was also up-regulated (p < 0.01). The pHi of HL-60 cells increased from 7.11 to 7.46 after treatment with etoposide for 24 hours. Treatment with cariporide could block etoposide-induced alkalinisation and enhance the apoptosis HL-60 cells. It is concluded that the expression of NHE1 is up-regulated in process of apoptosis of HL-60 cells induced by etoposide and the apoptosis depends on the pH increase caused by NHE1 higher expression.