Effect of Thrombolysis on Circulating Microparticles in Patients with ST-Segment Elevation Myocardial Infarction.

Objective: We demonstrated that circulating microparticles (MPs) are increased in patients with coronary heart disease (both chronic coronary syndrome (CCS) and acute coronary syndrome). Whether thrombolysis affects MPs in patients with ST-segment elevation myocardial infarction (STEMI) with or without percutaneous coronary intervention (PCI) is unknown. Methods: This study was divided into three groups: STEMI patients with thrombolysis (n = 18) were group T, patients with chronic coronary syndrome (n = 20) were group CCS, and healthy volunteers (n = 20) were the control group. Fasting venous blood was extracted from patients in the CCS and control groups, and venous blood was extracted from patients in the T group before (pre-T) and 2 hours after (post-T) thrombolysis. MPs from each group were obtained by centrifugation. After determining the concentration, the effects of MPs on endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase (iNOS) in rat myocardial tissue in vitro were detected by immunohistochemistry and western blotting. Changes in nitric oxide (NO) and oxygen free radicals (O2•-) were also detected. The effect of MPs on vasodilation in isolated rat thoracic aortae was detected. Results: Compared with that in the control group (2.60 ± 0.38 mg/ml), the concentration of MPs was increased in patients with CCS (3.49 ± 0.72 mg/ml) and in STEMI patients before thrombolysis (4.17 ± 0.58 mg/ml). However, thrombolysis did not further increase MP levels (post-T, 4.23 ± 1.01 mg/ml) compared with those in STEMI patients before thrombolysis. Compared with those in the control group, MPs in both CCS and STEMI patients before thrombolysis inhibited the expression of eNOS (both immunohistochemistry and western blot analysis of phosphorylation at Ser1177), NO production in the isolated myocardium and vasodilation in vitro and stimulated the expression of iNOS (immunohistochemistry and western blot analysis of phosphorylation at Thr495), and the generation of O2•- in the isolated myocardium. The effects of MPs were further enhanced by MPs from STEMI patients 2 hours after thrombolysis. Conclusion: Changes in MP function after thrombolysis may be one of the mechanisms leading to ischemia-reperfusion after thrombolysis.

[Study on Application of RVD Regimen Sequential Auto-HSCT in the Treatment of Multiple Myeloma Evaluated by Propensity Score Matching].

OBJECTIVE: To investigate the application effect of sequential autologous hematopoietic stem cell transplantation (Auto-HSCT) with lenalidomide, bortezomib and dexamethasone (RVD) in the treatment of multiple myeloma (MM) evaluated by propensity score matching. METHODS: The clinical data of 49 MM patients treated with RVD scheme and followed-up for 36 months in the hospital from January 2015 to January 2021 were retrospectively analyzed and included in the control group, the clinical data of 54 MM patients who received RVD scheme and sequential Auto-HSCT scheme and completed 36 months of follow-up in the hospital during the same period were collected and included in the observation group. PSM method (1∶1, caliper value=0.01) was used to match the control group with the observation group based on baseline data and laboratory indexes, covariate equilibrium samples were obtained between groups (40 cases in each group). The clinical efficacy of patients in the two groups after 18 weeks of treatment was compared; the incidence of toxic and side effects during treatment of patients in the two groups was compared; the survival of patients in the two groups was compared after 36 months of follow-up. RESULTS: The ORR and DCR in the observation group were higher than those in the control group, the difference was statistically significant (P<0.05). Compared the incidence of fatigue, rash, thrombocytopenia, anemia and nausea of patients in the two groups, there was no statistical significant difference (P>0.05). After 36 months of follow-up (no loss during follow-up), 4 cases died from illness in the observation group, with a survival rate of 90% and an average survival time of 35.61 (95% CI: 35541-35.685) months, 10 cases died from illness in the control group, with a survival rate of 75% and an average survival time of 34.70 (95% CI: 34.559-34.832) months, the survival rate of the observation group was higher than that of the control group, the difference was statistically significant (P<0.05). CONCLUSION: Sequential Auto-HSCT with RVD regimen in the treatment of MM can improve the short-term efficacy and increase the survival rate of patients, which will not increase toxic and side effects and has high safety.

Biomarkers of Planarian Dugesia japonica in Response to Herbicide Glyphosate Exposure.

As the worldwide top-selling herbicide, glyphosate is ubiquitously distributed in the natural environment, and its influence on the ecological safety and human health has being increasingly concerned. In this study, mRNA expressions of GPX and three heat shock protein genes in freshwater planarian Dugesia japonica in response to glyphosate were determined, and two oxidative stress parameters were measured. The results suggested that GPX activity can be used as a more sensitive biomarker in contrast with GPX gene expression, and mRNA expressions of Hsp70, Hsp90 genes are more sensitive than Hsp40 for planarians in response to glyphosate stress. Besides, the deduced T-AOC as well as varied GPX activity and mRNA expression levels of Hsps also indicated that glyphosate exposure would inhibit antioxidation and induce oxidative stress in D. japonica, while specific antioxidant systems and stress proteins tried to protect cells by their own regulation. The results of this study will be helpful to elucidate the stress response mechanisms of freshwater planarians to herbicide glyphosate.

A novel sigma class glutathione S-transferase gene in freshwater planarian Dugesia japonica: cloning, characterization and protective effects in herbicide glyphosate stress.

As the top-selling herbicide in the world, glyphosate distributes widely in natural environment and its influence on the ecological security and human health has attracted more and more concern. Glutathione S-transferases (GSTs) are a well-characterized superfamily of isoenzymes for cellular defense against exogenous toxic substances and therefore protect organisms from injury. In this study, the complete cDNA sequence of GST gene (named as Dja-GST) in freshwater planarian Dugesia japonica was firstly cloned by means of RACE method. The full-length Dja-GST comprises of 706 nucleotides which encodes a polypeptide of 200 amino acids. Dja-GST has two representative GST domains at the N- and C-termini. The conservative GST-N domain includes G-site Y8, F9, R14, W39, K43, P52 and S64, while the variable GST-C domain contains H-site K104, V156, D159 and L161. Sequence analysis, phylogenetic tree reconstruction and multiple alignment collectively indicate that Dja-GST belongs to the Sigma class of GST superfamily. Also, GST gene expression profile, GST enzymatic activity and MDA content in response to glyphosate exposure were systematically investigated and the correlations among them were analyzed. The results suggest that glyphosate exposure modified the mRNA transcription and enzymatic activity of GST, as well as the MDA content in planarians, indicating that Dja-GST might play an important part in organisms defending against oxidative stress induced by glyphosate. This work lays a molecular foundation for further exploring the exact functions of Dja-GST and gives an important implication for evaluating the ecological environment effects of herbicide glyphosate.

[Intervention effect of lipoxygen receptor agonist BML-111 on acute liver injury in rats and its mechanism].

Objective: To investigate the effect and mechanism of lipoxygen on acute liver injury. Methods: Twenty-four SD rats were randomly divided into 4 groups (n=6): normal control group: subcutaneous injection of olive oil at a dose of 1.8 ml/kg; model group: subcutaneous injection of 40% carbon tetrachloride(CCL4)oil (olive oil as a solvent) at a dose of 3 ml/kg; BML-111 treatment group: Lipoxin receptor agonist BML-111 was injected subcutaneously at a dose of 1 mg/kg, and treated in the same model group after 30 minutes; BOC-2 blocker group: Lipoxin receptor blocker BOC-2 was injected subcutaneously at a dose of 50 µg/kg. After 30 minutes, the treatment was the same as BML-111 group. HE staining was used to observe the pathological changes of liver tissues to judge the liver injury. Serological detection was used to determine the activities of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST); The myeloperoxidase (MPO) activity in rat liver tissue was detected by kit method; the contents of of angiotensin converting enzyme (ACE) , Angiotensin converting enzyme 2 (ACE2), angiotensin II (AngII) and angiotensin 1-7 (Ang- (1-7)) were detected by ELISA. Western Blot was used to detect the protein contents of Ang II and Ang- (1-7) in liver tissue. Results: The treatment group had less liver damage than the model group and the blocker group; BML-111 decreased the levels of ACE and AngII in serum of rats with CCL4 injury (P＜0.01) and increased the levels of ACE2 and Ang- (1 in serum -7) content (P＜0.01). BML-111 increased the content of Ang- (1-7) in liver tissue and decreased the content of AngII in CCL4 injured rat tissue. Conclusion: The results showed that the intervention effect and mechanism of lipoxygen receptor agonist BML-111 on acute liver injury in rats may be related to the regulation of AngII and Ang-(1-7).

CuZnSOD and MnSOD from freshwater planarian Dugesia japonica: cDNA cloning, mRNA expression and enzyme activity in response to environmental pollutants.

As an important antioxidant enzyme, the superoxide dismutase (SOD) can protect aerobic organisms from oxidative damage through catalyzing the dismutation of superoxide into hydrogen peroxide and oxygen. The SODs have been cloned in some species and their dynamic expression or enzymatic activity in response to environmental stressors were investigated. In the current study, the full-length cDNA of two SODs from freshwater planarian Dugesia japonica were firstly cloned (named as DjCuZnSOD and DjMnSOD, respectively). The complete cDNA of DjCuZnSOD consists of 661 nucleotides encoding 186 amino acids while the 765 bp DjMnSOD encodes a polypeptide of 226 residues. Sequence analysis and multiple alignment showed that DjCuZnSOD possesses two CuZnSOD family signature motifs and an N-terminal signal peptide suggesting it is an extracellular secretory protein. DjMnSOD possesses the MnSOD family signature sequence and is predicted to be located in mitochondrion with a mitochondrial targeting sequence. Phylogenetic analysis based on CuZnSOD and MnSOD orthologs from representative species further verified that DjCuZnSOD is an extracellular CuZnSOD while DjMnSOD is a mitochondrial MnSOD. For the purpose of studying their potential role against environmental pollutants, D. japonica were exposed to glyphosate or 1-decyl-3-methylimidazolium bromide ([C10mim]Br), and the mRNA expression levels of DjCuZnSOD and DjMnSOD along with total SOD activity were measured. The results showed that DjCuZnSOD exhibited more sensitive expression profiles in response to environmental pollutants in contrast with DjMnSOD, and the total SOD activity in response to both pollutants was more related to the expression level of DjCuZnSOD than to DjMnSOD, indicating that the mRNA expression of CuZnSOD would be a more sensitive biomarker than MnSOD in monitoring the pollution of aquatic environment and CuZnSOD might play more important role than MnSOD in eliminating superoxide anions caused by pollutants in D. japonica.

Molecular cloning, characterization, expression and enzyme activity of catalase from planarian Dugesia japonica in response to environmental pollutants.

Catalase (CAT) is an important antioxidant enzyme that protects aerobic organisms against oxidative damage by degrading hydrogen peroxide to oxygen and water. CAT mRNAs have been cloned from many species and employed as useful biomarkers of oxidative stress. In the present study, we cloned the cDNA sequence of CAT gene from freshwater planarian Dugesia japonica (designated as DjCAT) by means of RACE method. Sequence analysis and multiple alignment jointly showed that the full-length cDNA sequence consists of 1734 nucleotides, encoding 506 amino acids. Three catalytic amino acid residues of His71, Asn144 and Tyr354, two CAT family signature sequences of a proximal active site signature (60FDRERIPERVVHAKGGGA77) and a heme-ligand signature motif (350RLFSYRDTQ358) are highly conserved, suggesting that the DjCAT belongs to the NADPH and heme-binding CAT family and has similar functions. In addition, the transcriptional level of CAT gene and activity of CAT enzyme upon acute exposure of environmental pollutants glyphosate and 1-decyl-3-methylimidazolium bromide ([C10mim]Br) were investigated systematically. The variation of CAT mRNA expression in D. japonica was quantified by real-time PCR and the results indicated that it was up-regulated after exposure to glyphosate or [C10mim]Br with a dose-dependent manner but not linearly. Even though the variation trend of CAT activity upon glyphosate stress was not monotonously increased and inconsistent with that after [C10mim]Br exposure on day 1 and 3 sampling time, with the duration prolonged to day 5 they both presented a dose-dependent increase and the differences achieved extreme significance in all treated groups compared to the control. These findings suggested that DjCAT plays an important role in antioxidant defense in D. japonica, and the mRNA expression of CAT would also be used as an effective biomarker to monitor the pollution in aquatic environment just like its corresponding enzyme.

ß1 integrin-mediated multicellular resistance in hepatocellular carcinoma through activation of the FAK/Akt pathway.

Objective To explore the role and mechanism of ß1 integrin in the regulation of multicellular drug resistance in hepatocellular carcinoma (HCC). Methods This in vitro study used a liquid overlay technique to obtain multicellular spheroids of two human HCC cell lines, HepG2 and Bel-7402. The morphology of the spheroids was observed by optical and electron microscopy. The effects of exposure to 5-fluorouracil (5-FU) and cisplatin (CDDP) on cell proliferation and the induction of apoptosis were assessed in monolayer cells and multicellular spheroids. The levels of ß1 integrin and the effects on the focal adhesion kinase (FAK)/protein kinase B (Akt) pathway were evaluated using Western blot analysis, immunofluorescence and flow cytometry. The role of ß1 integrin was confirmed by using an inhibitory antibody. Results Cell proliferation inhibition and cell apoptosis induced by 5-FUl and CDDP were abrogated in multicellular spheroids compared with monolayer cells. There were high levels of ß1 integrin in multicellular spheroids. ß1 integrin inhibitory antibody prevented the formation of multicellular spheroids, coupled with a significant increase in proliferation inhibition and apoptosis induction. ß1 integrin inhibitory antibody effectively suppressed activation of both FAK and Akt in multicellular spheroids. Conclusions ß1 integrin mediated multicellular drug resistance through the FAK/Akt pathway in HCC spheroids.

A common genetic variation in CEBPE and acute lymphoblastic leukemia: a meta-analysis of the available evidence.

Acute lymphoblastic leukemia (ALL) has been studied intensively for decades, but the details of its etiology and underlying mechanisms have yet to be fully elucidated. It is now generally acknowledged that genetic factors contribute greatly to the development of this disease. The gene encoding CCAAT/enhancer-binding protein ε (CEBPE) is involved in the development of leukemia, and in particular the rs2239633 single nucleotide polymorphism (SNP) of CEBPE. The association between rs2239633 and risk of ALL has been well studied, but remains unclear. Therefore, a meta-analysis was performed in this study to establish a more precise estimation of that relationship. A comprehensive literature search of the PubMed electronic database was conducted, and relevant studies published up to February 20, 2015 were selected for analysis. The references of the retrieved articles were also screened. The extracted data were analyzed statistically, and pooled odds ratios with 95% confidence intervals were calculated using Review Manager (version 5.2) to estimate the association strength. Finally, eleven studies were included in the meta-analysis. The pooled analyses revealed that rs2239633 was associated with an increased risk of childhood ALL in Caucasians under any contrast models (P<0.01). However, this SNP did not affect the risk of ALL in adulthood among Caucasians, or in childhood among East Asians. In conclusion, these findings confirm that the CEBPE rs2239633 SNP could be considered a good marker of pediatric ALL risk in Caucasians, but not in East Asians; it is not a good marker of adult ALL risk in Caucasians.

[Advance of studies on microRNA and myelodysplastic syndrome].

MicroRNA (miRNA), evolutionarily conserved, endogenous, small, noncoding RNA molecule of about 22 nucleotides in length, have been recently attributed a crucial role in numerous physiological and pathological processes including the regulation of cellular development, differentiation, proliferation, apoptosis and oncogenesis. Myelodysplastic syndrome (MDS) is a heterogeneous group of clonal hematologic disorders characterized clinically and morphologically by ineffective hematopoiesis and increased risk of leukaemic transformation. The role of miRNA abnormal expression in pathogenesis and prognosis of MDS is reviewed in this article, including miRNA related with pathogenesis, miRNA related with prognosis of MDS and so on.

[In vitro killing effect of mutant thymidine kinase mediated by lentiviral vector on T lymphocytes].

OBJECTIVE: To explore the killing effect of the mutant herpes simplex virus thymidine kinase (HSV-sr39tk) and its wild-type (HSV-tk) mediated by lentiviral vector on T lymphocytes in vitro and compare T cell survival rate after GCV or ACV treatment. METHODS: The three-plasmid lentiviral vector system including packaging plasmid DeltaNRF, envelope plasmid VSV-G and vector plasmid (pTK151 + HSV-sr39tk or pTK151 + HSV-tk) were cotransfected into human embryonic kidney 293T cells using modified calcium phosphate precipitation methods. The packaged virus was harvested 72 h later. The survival of T cells expressing HSV-sr39tk or HSV-tk was measured by MTT assay after 4 day-culture against a gradient of GCV or ACV concentrations. RESULTS: The three plasmids were effectively cotransfected and a high titre of lentivirus was obtained (2 x 10(6) IU/ml). 39tk(+) T cell survival rates declined promptly when the prodrug GCV/ACV concentrations increased from 0 micromol/L to 10 micromol/L. The T cell survival rates in GCV group declined from (96.04 +/- 3.23)% to (36.76 +/- 4.38)% while in ACV group from (97.31 +/- 4.61)% to (43.75 +/- 8.99)%. However, when GCV/ACV concentrations were more than 10 micromol/L, further decline of 39tk(+) T cell survival rates became unobvious. The growth rate of 39tk(+) T cell exposed to GCV or ACV was obviously lower than that in un-transfected T cells (P < 0.05). Tk(+) T cells were sensitive to GCV (P < 0.05), but not to ACV (P > 0.05). There was a significant difference in killing effects between 39tk(+) T cell + GCV group and tk(+) T cell + GCV group (P < 0.05). CONCLUSION: The lentiviral vectors containing HSV-sr39tk gene could infect T lymphocytes effectively and stably without affecting the proliferation of the transduced cell. In contrast to HSV-tk gene, T cells infected HSV-sr39tk were more sensitive not only to GCV but also to ACV.